Case Studies & Application Stories

ORP Applications – MyronLMeters.com

Posted by 26 Aug, 2013

TweetWHAT IS ORP? Oxidation Reduction Potential or Redox is the activity or strength of oxidizers and reducers in relation to their concentration. Oxidizers accept electrons, reducers lose electrons. Examples of oxidizers are: chlorine, hydrogen peroxide, bromine, ozone, and chlorine dioxide. Examples of reducers are sodium sulfite, sodium bisulfate and hydrogen sulfide. Like acidity and alkalinity, […]

WHAT IS ORP?

Oxidation Reduction Potential or Redox is the activity or strength of oxidizers and reducers in relation to their concentration. Oxidizers accept electrons, reducers lose electrons. Examples of oxidizers are: chlorine, hydrogen peroxide, bromine, ozone, and chlorine dioxide. Examples of reducers are sodium sulfite, sodium bisulfate and hydrogen sulfide. Like acidity and alkalinity, the increase of one is at the expense of the other.

A single voltage is called the Oxidation-Reduction Potential, where a positive voltage shows a solution attracting electrons (oxidizing agent). For instance, chlorinated water will show a positive ORP value whereas sodium sulfite (a reducing agent) loses electrons and will show a negative ORP value.

ORP is measured in millivolts (mV), with no correction for solution temperature. Like pH, it is not a measurement of concentration directly, but of activity level. In a solution of only one active component, ORP indicates concentration. As with pH, a very dilute solution will take time to accumulate a measurable charge.

An ORP sensor uses a small platinum surface to accumulate charge without reacting chemically. That charge is measured relative to the solution, so the solution “ground” voltage comes from the reference junction – the same type used by a pH sensor.

HISTORY OF ORP

ORP electrodes were first studied at Harvard University in 1936. These studies showed a strong correlation of ORP and bacterial activity. These tests were confirmed by studies on drinking water and swimming pools in other areas of the world. In 1971 ORP (700 mV) was adopted by the World Health Organization (WHO) as a standard for drinking water. In 1982 the German Standards Agency adopted the ORP (750 mV) for public pools and in 1988 the National Swimming Pool Institute adopted ORP (650 mV) for public spas.

WHERE IS ORP USED?
As you can tell by the previous paragraphs, ORP is used for drinking water, swimming pools and spas. However, ORP is also used for cooling tower disinfection, groundwater remediation, bleaching, cyanide destruction, chrome reductions, metal etching, fruit and vegetable disinfection and dechlorination.

In test after test on poliovirus, E. coli, and other organisms, a direct correlation between ORP and the rate of inactivation was determined. It is, therefore, possible to select an individual ORP value, expressed in millivolts, at which a predictable level of disinfection will be achieved and sustained regardless of variations in either oxidant demand or oxidant concentration. Thus, individual ORP targets, expressed in millivolts, can be determined for each application, which will result in completely reliable disinfection of pathogens, oxidation of organics, etc. Any level of oxidation for any purpose can be related to a single ORP number which, if maintained, will provide utterly consistent results at the lowest possible dosage.

WHY USE ORP?

ORP is a convenient measure of the oxidizer’s or reducer’s ability to perform a chemical task. ORP is not only valid over a wide pH range, but it is also a rugged electrochemical test, which can easily be accomplished using in-line and handheld instrumentation. It is by far a more consistent and reliable measurement than say chlorine alone.

LIMITATIONS FOR ORP
As with all testing, ORP has certain limitations. The speed of response is directly related to the exchange current density which is derived from concentration, the oxidation reduction system, and the electrode. If the ORP of a sample is similar to the ORP of the electrode, the speed will be diminished.

Carryover is also a possible problem when checking strong oxidizers or reducers, and rinsing well will help greatly.

Although a better indicator of bactericidal activity, ORP cannot be used as a direct indicator of the residual of an oxidizer due to the effect of pH and temperature on the reading. ORP can be correlated to a system by checking the oxidizer or reducer in a steady state system with a wet test, and measuring pH. If the system stays within the confines of this steady state parameter (usually maintained by in- line or continuous control), a good correlation can be made. The best recommendation for ORP is to use wet tests, and over three test periods correlate the ORP values to those test parameters.

FREE CHLORINE CONVERSION USING ORP

The most ubiquitous and cost-effective sanitizing agent used in disinfection systems is chlorine. When chlorine is used as the sanitizer, free chlorine measurements are required to ensure residual levels high enough for ongoing bactericidal activity. Myron L meters accurately convert ORP measurements to free chlorine based on the understanding of the concentrations of the forms of free chlorine at a given pH and temperature. The conversion is accurate when chlorine is the only oxidizing/reducing agent in solution and pH is stable between 5 and 9. This pH range fits most applications because pH is usually maintained such that the most effective form of free chlorine, hypochlorous acid, exists in the greatest concentration with respect to other variables such as human tolerance.

MYRON L METERS

Myron L offers a variety of handheld instruments and in-line Monitor/controllers that may be used to measure, monitor and/or control ORP. The latest is the Ultrapen PT3, ORP/Redox and Temperature Pen. The Ultrameter III™ 9PTKA, Ultrameter II™ 6PFCE, PoolPro™ PS6FCE and PS9TK, and D-6 Digital Dialysate Meter™ are multi-parameter handheld instruments with ORP and FCE free chlorine measuring capabilities. These instruments also have the capability to measure conductivity, TDS, resistivity, pH, mineral/salt concentration and temperature, making them the preferred instruments for all water treatment professionals. The 720 Series II Monitor/controllers are an excellent choice for continuous in-line measurements.

For additional information, visit us at MyronLMeters.com.

Categories : Case Studies & Application Stories, Science and Industry Updates

ORP Monitoring Reduces Textile Company’s Harsh Chemical Use

Posted by 16 Aug, 2013

Tweet ORP monitoring reduced this company’s consumption of harsh chemicals When Lafayette South America textile manufacturer in Bogota, Colombia, couldn’t find the little blue paper strips it had previously used to test for the presence of sodium hydrosulphite in its post reduction dyebath, it went looking for an alternative. Hyman Abadi, Lafayette’s cofounder, found a […]

ORP monitoring reduced this company’s consumption of harsh chemicals

When Lafayette South America textile manufacturer in Bogota, Colombia, couldn’t find the little blue paper strips it had previously used to test for the presence of sodium hydrosulphite in its post reduction dyebath, it went looking for an alternative. Hyman Abadi, Lafayette’s cofounder, found a better testing solution and new automatic methods of monitoring and controlling chemical feeds in : the Ultrameter II 6 Parameter handheld digital meter; the 720II in-line ORP monitor/controller; the 720II pH monitor/controller; and the TechPro PH1.

Hyman’s technicians use the Ultrameter II 6P to instantly test for ORP in the textile dyeing process and continuous reduction washing of printed and dyed fabrics.  Lafayette also uses the Ultrameter II to spot check ORP against the performance of automatic in-line monitor/controllers now in use.

Lafayette also uses 720II Series ORP Monitor/controllers to automatically control the amount of sodium hydrosulphite added to reduce the remaining solution in the textile bath. Before Myron L in-line Monitor/controllers were used, chemical had to constantly be added by hand to ensure product quality.  Now, if the concentration is low, the monitor/controller opens a valve that releases the reducing solution into the bath.  If it’s high, the valve remains closed. To ensure the process stays in control, spot checks on the reduction bath are conducted twice daily using the handheld Ultrameter IIs.

The Myron L 720II Series pH Monitor/controllers are used to balance the bath by controlling the amount of caustic soda added to maintain the appropriate pH level.  Accurately maintaining the pH ensures the effectiveness of the reducing agent, thereby decreasing chemical consumption. With sodium hydrosulphite, the pH must be maintained at around 10.  If the pH drops below that level, it decomposes rapidly and loses its reduction efficiency.

In dyeing, the pH is kept at 5.5 to 6. This is important because the dyes themselves are susceptible to color changes outside of this pH range, until they diffuse into the fiber and become “fixed.” Once properly applied in the fiber, they are protected from these variations in pH.  However, the unfixed dye remaining on the surface of the fiber must be removed in order to ensure subsequent proper wash fastness and color “bleeding”. This unfixed dye is removed by raising the pH along with the use of sodium hydrosulfite. Careful control of this reductive process removes the unfixed surface dye, without affecting the properly applied fixed dye. (The dyes must remain in their soluble form to enter the fibers of the fabric. They are then mechanically trapped as the pH level is raised in the reduction process and the unused dye is cleansed from solution.)

Maintaining the pH not only assists in the dyeing process, it also ensures reproducibility of color between the lab and the dyebath and from batch to batch by ensuring that the dyes are always applied in their optimum pH range of color stability. The solubility of dyes is dependent on pH and varies from dye to dye. If the pH of the dyebath is out of range for the dye type, the color will be off shade or incorrect altogether.  Lafayette uses TechPro PH1 meters to measure grab samples as a confidence check against the equipment installation and functioning.  PH1s are also in use throughout the factory for other solution quality control.

Due to Hyman’s implementation of basic water quality control in dyebath solutions, Lafayette is now generally able to use half of the chemicals it had previously used for this same process.  Lafayette has drastically reduced costs, noxious fumes in the factory and the amount of harmful chemicals that must be removed before effluent is discharged into local rivers, creating a win-win situation for the company, its employees and the environment.

Myron L Meters is the premier online internet retailer of Myron L products.  Find out more about the Ultrameter II 6P here:

https://www.myronlmeters.com/Myron-L-6P-Ultrameter-II-Multiparameter-Meter-p/dh-umii-6pii.htm

Categories : Case Studies & Application Stories

Using LSI to preserve an Arizona treatment plant’s distribution systems

Posted by 16 Aug, 2013

Tweet                    The first thing anyone who manages water and wastewater learns is that water is the universal solvent. Because of the unique properties of that dihydrogen monoxide molecule, owing to the extreme electronegativity of the oxygen atom, water is highly polarized and dissolves almost everything with […]

Myron L Ultrameter II 6P

 

 

 

 

 

 

 

 

 

 

The first thing anyone who manages water and wastewater learns is that water is the universal solvent. Because of the unique properties of that dihydrogen monoxide molecule, owing to the extreme electronegativity of the oxygen atom, water is highly polarized and dissolves almost everything with which it comes into contact. This fact is important when one has to maintain equipment and structures that process and distribute water because what the water has dissolved in it can cause it to be corrosive or scaling. What water generally has dissolved in it is at least some carbon dioxide and some calcium carbonate.

Carbon dioxide is ubiquitous and dissolves at the surface of the water, forming carbonic acid in solution. Calcium carbonate, dissolved by the carbonic acid, is globally present in rock formations (limestone), as well as in the physiological structures of organisms (particularly oceanic organisms) that excrete it. Calcium carbonate in its various forms is also used to buffer pH and stabilize solution in process control. Managing the calcium carbonate equilibrium becomes critical to managing any water and wastewater treatment process.

Too little calcium carbonate yields water that is not saturated and may cause corrosion and deteriorate equipment and structures. A supersaturated solution will likely precipitate calcium carbonate, causing scale, reducing efficiency and eventually leading to system failure.

LSI in AZ

One method for analyzing and managing corrosion and scale deposition of water is to use the Langelier Saturation Index (LSI). In Scottsdale, Ariz., Gary Lyons is managing LSI at his water treatment facility using the Myron L Ultrameter II 6P.

His drinking water treatment plant takes 70 million gal per day (mgd) of water from the Central Arizona Project canal and treats it for residential and commercial use. Within the 143-acre campus, the plant processes 20 mgd to of wastewater from the city of Scottsdale collection system using microfiltration and reverse osmosis (RO). Water coming from the RO treatment process is acidic around pH 5.5. It is then moved to decarbonation towers and lime is added to bring the LSI value close to zero. The water reclamation plant features 8 mgd of storage capacity. Recycled water treated by the plant is used for the irrigation of 20 Scottsdale golf courses.

There is great concern about how the water balance will affect this distribution system over time, especially due to higher total dissolved solids values. Plant technicians compute LSI values in the field with the 6Psi hand-held to determine what adjustments should be made and how in real time. The LSI calculator allows them to perform what-if scenarios on changes in pH, alkalinity, hardness and temperature. They are able to measure the effects of changes immediately as well in the facility and at distribution points.

Hardness and alkalinity are variables in the LSI calculation because they account for the availability of calcium in various forms in the water. Variables such as temperature and pH contribute to the likelihood of the formation of calcium carbonate.

The version of the LSI calculation used by the 6Psi LSI calculator is:

LSI = pH + TF + CF + AF – 12.1

In this calculation, pH = the measured value of pH in pH units; TF = 0.0117 x temperature – 0.4116; CF = 0.4341 x ln(Hrd) – 0.3926; and AF = 0.4341 x ln(AL) – 0.0074.

The first thing anyone who manages water and wastewater learns is that water is the universal solvent. Because of the unique properties of that dihydrogen monoxide molecule, owing to the extreme electronegativity of the oxygen atom, water is highly polarized and dissolves almost everything with which it comes into contact. This fact is important when one has to maintain equipment and structures that process and distribute water because what the water has dissolved in it can cause it to be corrosive or scaling. What water generally has dissolved in it is at least some carbon dioxide and some calcium carbonate.

Carbon dioxide is ubiquitous and dissolves at the surface of the water, forming carbonic acid in solution. Calcium carbonate, dissolved by the carbonic acid, is globally present in rock formations (limestone), as well as in the physiological structures of organisms (particularly oceanic organisms) that excrete it. Calcium carbonate in its various forms is also used to buffer pH and stabilize solution in process control. Managing the calcium carbonate equilibrium becomes critical to managing any water and wastewater treatment process.

Too little calcium carbonate yields water that is not saturated and may cause corrosion and deteriorate equipment and structures. A supersaturated solution will likely precipitate calcium carbonate, causing scale, reducing efficiency and eventually leading to system failure.

Indicator Analysis

LSI has been useful as a scaling/corrosion indicator in municipal water treatment for more than 70 years. The original Langelier Saturation (or Stability) Index calculation was developed by Dr. Wilfred Langelier in 1936 to be used as a tool to develop strategies to counteract corrosion of plumbing in municipal water distribution systems. It is a statement about the change in pH required to bring the calcium carbonate in water to equilibrium. LSI is a measure of the disparity between the pH of the system and the pH at which the system is saturated with calcium carbonate: LSI = pH – pH of saturation.

As such, the LSI indicates the change in pH required to bring water to equilibrium. If the LSI is +1, then the pH needs to be lowered by one unit to bring the water to equilibrium. If the LSI is -1, the pH needs to be raised by one unit to bring the water to equilibrium.

A positive saturation index means that the pH of the water is above equilibrium. The water is scaling because as pH increases, total alkalinity concentration increases. This is due to an increase in the carbonate ion, which bonds with calcium ions present in solution to form calcium carbonate (reference the carbonic acid equilibrium, in which hydrogen ions bond with carbonate ions to form bicarbonate and hydrogen ions bond with bicarbonate to form carbonic acid). Thus, any positive value for LSI is scaling.

If the pH is less than the pH of saturation, the index will be negative, which is corrosive. This means that the water is more acidic than it would be at equilibrium. There are less carbonate ions present, according to the carbonic acid equilibrium. The water will be aggressive because it has room for more ions in solution. Thus, any negative value for LSI indicates that the water may tend to be corrosive.

The use of LSI as an indicator is well documented and time-tested. Managing water balance through LSI analysis will prevent loss of efficiency and failure of equipment and structures, saving time and money.

Myron L Meters is the premier online internet retailer of the Myron L Ultrameter II 6P.  Find out more about the Ultrameter II 6P here:

https://www.myronlmeters.com/Myron-L-6P-Ultrameter-II-Multiparameter-Meter-p/dh-umii-6pii.htm

Categories : Application Advice, Case Studies & Application Stories, Technical Tips

Using the Ultrameter II 6P in a Power Plant

Posted by 16 Aug, 2013

TweetFind out how a plant chemistry and O&M technician with 18 years experience, uses the Ultrameter II 6P to optimize blowdowns and control corrosion, scale, contamination & chemicals Deborah Walker, an operation and maintenance technician and plant chemistry technician in manufacturing and energy production has been managing water quality in industrial processes for more than […]

The Ultrameter II 6P

The Ultrameter II 6P

Find out how a plant chemistry and O&M technician with 18 years experience, uses the Ultrameter II 6P to optimize blowdowns and control corrosion, scale, contamination & chemicals

Deborah Walker, an operation and maintenance technician and plant chemistry technician in manufacturing and energy production has been managing water quality in industrial processes for more than 18 years. Through her extensive experience, she has come to rely on the Myron L Ultrameter II as a way to monitor control parameters that ensure the functioning of automatic controllers and chemical dosers that optimize cooling tower blowdown schedules; prevent scale, corrosion and microbiological fouling; screen influent and effluent for process parameter control and environmental compliance; as well as directly measuring parameters critical to a total quality assurance plan.

Deborah’s most recent use of the Ultrameter II 6P  was in a high output power plant implementing a Heat Recovery Steam Generator (HRSG), gas and steam turbines, all required heat exchangers, cooling towers, and chemical controllers that preserved the life of the equipment and structures in the water circulation loop while minimizing water and energy consumption. Deborah used the UMII as part of quality assurance for all water and steam quality. Make up water for this application was sourced from a massive municipal pipeline with wastewater being discharged into a nearby creek.

Much of the online controllers Deborah monitored featured an online sampling panel. Deborah used the Ultrameter II to draw solution from the panel to ensure the online meters that monitored cooling water throughout the system were functioning properly. Because the Ultrameter II 6P  measured all of the parameters critical to her operation, including conductivity, pH, ORP and temperature, she was able to efficiently analyze equipment functioning and chemical dosing quickly and accurately.

The Ultrameter II 6P also features data logging with memory for up to 100 readings, eliminating the need to perform record keeping tasks in the field. This means Deborah could monitor more areas of the plant in less time. Chemicals injected into the system included a cooling water dispersant that consisted of sodium bisulfate and sodium formaldehyde bisulfite. Sodium bisulfate effectively lowered the pH of the system and sodium formaldehyde bisulfite also served as an oxygen scavenger. (Removing oxygen from the system helps to prevent the formation of the hydroxide ion and hence the formation of rust, disrupting the processes of the corrosion cell. Tetrapotassium pyrophosphate is used for water stabilization and disrupts the corrosion process at the cathodic areas by combining with calcium or iron to form a complex film.) pH monitoring with the Ultrameter II 6P was required to ensure target levels as well as optimum chemical performance.

Deborah also used the Ultrameter II 6P as a quality check to maintain the HRSG. To do this, she tested the purity of the steam by measuring conductivity of steam at the sample panel for boiler chemistry control.

The steam that issued from the HRSG to the turbine had the potential to errode or deposit, which could affect energy efficiency, as well as damage equipment. Any deposits would add mass to the turbine, making it more difficult to turn with greater friction, requiring more energy for the mass with more energy lost as heat. Any increase in conductivity in the steam indicated that either something undesirable was in the water as it was coming in or that there was something wrong with the combustion chemistry—either the dirty water was carried over to the steam or the steam was eroding the boiler and picking up minerals from the metal components. If the steam was corrosive, preventative corrections could be made to stem any equipment damage. If other chemical contamination was evident, additional pretreatment and other chemical controls could be implemented.

Using the Ultrameter II 6P for steam quality control not only increased HRSG energy efficiency and equipment lifecycle, but also decreased its environmental footprint because some of the chemical contaminants that could form deposits could only be removed by other dangerous chemicals with extensive outage during maintenance. The operational target for specific conductivity blowdown identified by Deborah with the Ultrameter II was 1200-1400µS with a goal of 10 cycles of concentration.

Deborah also used the Ultrameter II as part of a disinfection program. Chlorine was used to mitigate biological fouling and corrosion. Chlorine injection occurred at 8 a.m. and 2 p.m. with blowdowns scheduled for once at night and once during the day. Deborah’s target residual level range for system disinfection was 0.2-0.6 ppm free chlorine. The bleach injection used in disinfection, however, not only interfered directly with pH control, but also with the effectiveness of other chemicals used to prevent scaling and corrosion.

Chlorine also had to be kept at a consistent reasonable level at all times to avoid shocking the system with massive doses, which could make the system erratic and difficult to balance. During a shock, biological growth could come loose as well, potentially clogging membranes or small pipes in the sample panel. Spot checking parameters such as pH, ORP and conductivity with the Ultrameter II was critical to ensuring consistent residual chlorine levels, pH, and scale and corrosion inhibitors between blowdowns.

The Ultrameter II 6Pwas used by Deborah to verify the accuracy of monitors that controlled demineralizer water used in other processes at the power plant. Three trains were employed to remove dissolved solids. The first vessel removed cations. The second vessel removed anions. The third was a mixed bed that removed both types. The Ultrameter II 6P  could be used to determine when the trains had become saturated and needed to be regenerated by measuring any increase in conductivity downstream from the beds. Acid injection was used to flush the demineralizer out, which was then rinsed. Deborah used the Ultrameter II to ensure that the brine wastewater that resulted was neutralized and documented its pH and conductivity before it was shipped away.

Deborah also had to mitigate the environmental impact of discharged cooling waters. She used the Ultrameter II 6P  to take measurements of pH and temperature of the water from a creek upstream of the plant to establish a baseline for compliance for the wastewater, so that she could get the water as close to the natural conditions of the creek as possible before discharge.

The chlorine injected to kill microbes and prevent fouling while the cooling water was being recirculated also had to be removed from the water before it entered the creek. This is because the chlorine could also kill desirable organisms important to the ecosystem of the creek, either by direct oxidation or accumulation to toxic levels in living tissues. If chlorine residual was above 0.2 ppm, the waste stream was diverted to sodium bisulfite skids. On the discharge side of the skids, Deborah used the Ultrameter II to test that sodium bisulfite was injected and effective at binding with and deactivating the chlorine by measuring the Oxidation Reduction Potential (ORP). ORP measured the total killing power of all sanitizers in solution by measuring the chemical activity, rather than any specific constituent. Deborah also checked the free chlorine level again specifically.

The sodium bisulfite skid itself also caused the pH of the water to vary slightly. So Deborah made a final check of the pH using the Ultrameter II. The pH was controlled to between 6.6 and 8.6 to optimize the efficacy of other chemicals in solution. The cooling tower would typically blow down within this range, but could be as high as the administrative limit, which was set at 8.7—still well within permit discharge limits, but only with special permission.

The outside blowdown line from the cooling tower dumped into a settling basin before it traveled out to the creek. Deborah used the Ultrameter II  6P to test conductivity, pH, ORP and free chlorine before the cooling water was discharged into the settling basin to ensure compliance with the established guidelines.

Part of effluent compliance also included a plan to monitor and control stormwater runoff from the plant. Deborah used the Ultrameter II 6P to monitor and report pH and conductivity following a major rain event.

Ranges for other operational limits include 80-130 mg/L (ppm) Ca, which usually runs at about 60 mg/L; 0-0.5 mg/L iron, which usually runs at about 0.30 mg/L; microorganism plate count of 0-104 cfu/mL, and suspended solids between 0-25 mg/L.

Deborah has also used the Ultrameter II 6P as part of a Quality Assurance plan for a prominent electric semiconductor manufacturer in which she used conductivity measurements to ensure semiconductor chip quality through proper rinsing.

Myron L Meters is the premier online internet retailer of the Myron L Ultrameter II 6P.  Find out more about the Ultrameter II 6P here:

https://www.myronlmeters.com/Myron-L-6P-Ultrameter-II-Multiparameter-Meter-p/dh-umii-6pii.htm

Categories : Application Advice, Case Studies & Application Stories, MyronLMeters.com Valued Customers, Technical Tips

Reverse Osmosis and Removal of Minerals from Drinking Water: Myron L Meters

Posted by 17 Jun, 2013

TweetMyron L Meters provides introductory as well as professional level material on water quality and water treatment. Did you know that Myron L Meters carries a meter specifically for testing RO systems (see below)? Water purification systems have purified brackish water and sea water for the military, businesses and farms in many different locations on […]

Myron L Meters provides introductory as well as professional level material on water quality and water treatment. Did you know that Myron L Meters carries a meter specifically for testing RO systems (see below)?

Water purification systems have purified brackish water and sea water for the military, businesses and farms in many different locations on planet Earth. Reverse osmosis water purification will create clean drinkable water when used on your drinking water.

Reverse osmosis will generally remove salt, manganese, iron, fluoride, lead, and calcium (Binnie et. al., 2002). Most mineral constituents of water are physically larger than water molecules and they are trapped by the semi-permeable membrane and removed from drinking water when filtered through an RO system (AllAboutWater.org, 2004). Meanwhile, consumers are concerned about the removal of minerals from their drinking water.
Reverse Osmosis (RO) removed 90-99.99% of all the contaminants including minerals from the drinking water supply (see Figure 1). RO removes minerals because they have larger molecules than water. The subject of minerals and RO created controversy and disagreement among water and health professionals. The World Health Organization (WHO) made clarification that majority of healthy minerals are needed for human body is from food or dietary supplementary sources and not from drinking tap water. In addition, minerals found in water can be harmful to human health. The evidence is strong that calcium and magnesium are essential elements for human body (WQA, 2011). However, its a weak argument to suggest that we should make up this deficiency through water consumption (WQA, 2011). Tap water presents a variety of inorganic minerals which the human body has difficulty absorbing (Misner, 2004). Their presence is suspect in a wide array of degenerative diseases, such as hardening of the arteries, arthritis, kidney stones, gall stones, glaucoma, cataracts, hearing loss, emphysema, diabetes, and obesity. What minerals are available, especially in “hard” tap water, are poorly absorbed, or rejected by cellular tissue sites, and, if not evacuated, their presence may cause arterial obstruction, and internal damage (Dennison, 193; Muehling, 1994; Banik, 1989).

Figure 1. Reverse Osmosis Membrane (Source:DOI-BUR, 2009)

Organic Minerals vs. Inorganic Minerals
There are two types of minerals in water, organic and inorganic. Human physiology has a biological affinity for organic minerals. Most organic minerals for our body functions come from dietary plant foods (Misner, 2004). A growing plant converts the inorganic minerals from the soils to a useful organic mineral (Misner, 2004). When an organic mineral (from a plant food) enters the stomach it must attach itself to a specific protein-molecule (chelation) in order to be absorbed, then it gains access to the tissue sites where it is needed (Misner, 2004). Once a plant mineral is divested within the body, it is utilized as a coenzyme for composing body fluids, forming blood and bone cells, and the maintaining of healthy nerve transmission (Balch & Balch 1990).

Reverse Osmosis has Little Effect on Water pH
Water pH levels will automatically change when water is ingested and comes into contact with the food in your stomach (Wise, 2011). Even on an empty stomach, your stomach acid alone is already several times more acidic than RO water (pH 6-8) with a pH level of 2 (Wise, 2011). The human body regulates pH levels constantly to find balance and equilibrium (see Figure 2). Therefore under normal conditions it will always maintain a neutral 7.4 pH balance (Wise, 2011). The healthy body is very robust and it will restore homeostatic pH fairly quickly and easily (Wise 2011). Soft drinks and sports drinks typically have a pH level of 2.5, orange juice has a 3 pH and coffee has a 4 pH level and we drink these beverages all the time without problems (Wise, 2011).

Figure 2. Comparison of pH Levels (Source: Wise, 2011)

Conclusion
Water filtered or treated by reverse osmosis is generally pure, clean, and healthy. A reverse osmosis treatment system is currently the only technology that can remove most of the emerging contaminants (i.e., prescription drugs and perchlorate) including other contaminants (i.e., arsenic, cyanide, and fluoride) that are difficult to remove by other treatment methods. No more ingesting of harmful inorganic minerals means the body will no longer be stressed with trying to absorb something that wasn’t supposed to be there in the first place (Wise, 2011). Consumers should not be concerned about the removal of minerals by RO system. As the WHO (2009) and WQA (2011) pointed out, the human body obtains the vast majority of minerals from food or supplements, not from drinking water.

One of the downsides to the reverse osmosis process is that it is so effective in removing particles, it will also remove minerals from your water that may be beneficial. The body needs certain minerals, such as calcium and magnesium, to function properly. In addition, some people believe minerals such as this actually add flavor to the water, so that will be missing if you filter the water. Some find a certain acidic taste to water that has been purified by reverse osmosis. A reverse osmosis system also wastes a certain amount of water. For every gallon of purified water, three or four gallons have to be processed. If water is scarce or expensive in your area, this is a strong consideration.

The Myron L RO-1 was developed years ago specifically for Culligan, and is designed for testing RO systems.

RO-1 Meter

The choice of professionals for years, this compact instrument has been designed specifically to demonstrate and test Point of Use (POU) reverse osmosis or distillation systems. By measuring electrical conductivity, it will quickly determine the parts per million/Total Dissolved Solids (ppm/TDS) of any drinking water.

With a single ‘before and after’ test, this handy device effectively demonstrates how your RO or distillation system eliminates harmful dissolved solids. It will also service test systems, including membrane evaluation programs. Find out more about the RO-1 meter HERE.

Categories : Case Studies & Application Stories, Product Updates, Science and Industry Updates

Basics of Wastewater and Sewage Treatment – MyronLMeters.com

Posted by 10 Jun, 2013

TweetWastewater is treated in 3 phases: primary (solid removal), secondary (bacterial decomposition), and tertiary (extra filtration). fig. 1 Origins of Sewage Sewage is generated by residential and industrial establishments. It includes household waste liquid from toilets, baths, showers, kitchens, sinks, and so forth that is disposed of via sewers. In many areas, sewage also includes […]

Wastewater is treated in 3 phases: primary (solid removal), secondary (bacterial decomposition), and tertiary (extra filtration).

fig. 1

Origins of Sewage

Sewage is generated by residential and industrial establishments. It includes household waste liquid from toilets, baths, showers, kitchens, sinks, and so forth that is disposed of via sewers. In many areas, sewage also includes liquid waste from industry and commerce. The separation and draining of household waste into greywater and blackwater is becoming more common in the developed world. Greywater is water generated from domestic activities such as laundry, dishwashing, and bathing, and can be reused more readily. Blackwater comes from toilets and contains human waste.

Sewage may include stormwater runoff. Sewerage systems capable of handling storm water are known as combined sewer systems. This design was common when urban sewerage systems were first developed, in the late 19th and early 20th centuries.  Combined sewers require much larger and more expensive treatment facilities than sanitary sewers. Heavy volumes of storm runoff may overwhelm the sewage treatment system, causing a spill or overflow. Sanitary sewers are typically much smaller than combined sewers, and they are not designed to transport stormwater. Backups of raw sewage can occur if excessive infiltration/inflow (dilution by stormwater and/or groundwater) is allowed into a sanitary sewer system. Communities that have urbanized in the mid-20th century or later generally have built separate systems for sewage (sanitary sewers) and stormwater, because precipitation causes widely varying flows, reducing sewage treatment plant efficiency.

As rainfall travels over roofs and the ground, it may pick up various contaminants including soil particles and other sediment, heavy metals, organic compounds, animal waste, and oil and grease. (See urban runoff.)[5] Some jurisdictions require stormwater to receive some level of treatment before being discharged directly into waterways. Examples of treatment processes used for stormwater include retention basins, wetlands, buried vaults with various kinds of media filters, and vortex separators (to remove coarse solids).

Sewage treatment is done in three stages: primary, secondary and tertiary treatment (Figure 1).

Primary Treatment
In primary treatment, sewage is stored in a basin where solids (sludge) can settle to the bottom and oil and lighter substances can rise to the top. These layers are then removed and then the remaining liquid can be sent to secondary treatment. Sewage sludge is treated in a separate process called sludge digestion.

Secondary Treatment
Secondary treatment removes dissolved and suspended biological matter, often using microorganisms in a controlled environment. Most secondary treatment systems use aerobic bacteria, which consume the organic components of the sewage (sugar, fat, and so on). Some systems use fixed film systems, where the bacteria grow on filters, and the water passes through them. Suspended growth systems use “activated” sludge, where decomposing bacteria are mixed directly into the sewage. Because oxygen is critical to bacterial growth, the sewage is often mixed with air to facilitate decomposition.

Tertiary Treatment
Tertiary treatment (sometimes called “effluent polishing”) is used to further clean water when it is being discharged into a sensitive ecosystem. Several methods can be used to further disinfect sewage beyond primary and secondary treatment. Sand filtration, where water is passed through a sand filter, can be used to remove particulate matter. Wastewater may still have high levels of nutrients such as nitrogen and phosphorus. These can disrupt the nutrient balance of aquatic ecosystems and cause algae blooms and excessive weed growth. Phosphorus can be removed biologically in a process called enhanced biological phosphorus removal. In this process, specific bacteria, called polyphosphate accumulate organisms that store phosphate in their tissue. When the biomass accumulated in these bacteria is separated from the treated water, these biosolids have a high fertilizer value. Nitrogen can also be removed using nitrifying bacteria. Lagooning is another method for removing nutrients and waste from sewage. Water is stored in a lagoon and native plants, bacteria, algae, and small zooplankton filter nutrients and small particles from the water.

Sludge Digestion & Disposal
Sewage sludge scraped off the bottom of the settling tank during primary treatment is treated separately from wastewater. Sludge can be disposed of in several ways. First, it can be digested using bacteria; bacterial digestion can sometimes produce methane biogas, which can be used to generate electricity. Sludge can also be incinerated, or condensed, heated to disinfect it, and reused as fertilizer.

When a liquid sludge is produced, further treatment may be required to make it suitable for final disposal. Sewage sludge scraped off the bottom of the settling tank during primary treatment is treated separately from wastewater. Sludge can be disposed of in several ways. First, it can be digested using bacteria; bacterial digestion can sometimes produce methane biogas, which can be used to generate electricity. Sludge can also be incinerated, or condensed, heated to disinfect it, and reused as fertilizer.

Typically, sludges are thickened (dewatered) to reduce the volumes transported off-site for disposal. There is no process which completely eliminates the need to dispose of biosolids. There is, however, an additional step some cities are taking to superheat sludge and convert it into small pelletized granules that are high in nitrogen and other organic materials. In New York City, for example, several sewage treatment plants have dewatering facilities that use large centrifuges along with the addition of chemicals such as polymer to further remove liquid from the sludge. The removed fluid, called “centrate,” is typically reintroduced into the wastewater process. The product which is left is called “cake,” and that is picked up by companies which turn it into fertilizer pellets. This product is then sold to local farmers and turf farms as a soil amendment or fertilizer, reducing the amount of space required to dispose of sludge in landfills. Much sludge originating from commercial or industrial areas is contaminated with toxic materials that are released into the sewers from the industrial processes. Elevated concentrations of such materials may make the sludge unsuitable for agricultural use and it may then have to be incinerated or disposed of to landfill.

Notably, throughout the development of excreta, wastewater, wastewater sludge and biosolids management – from the least developed to the most developed countries – there are in­evitable public concerns about how best to manage this “waste” that is also a resource. Putting biosolids to their best uses in each local situation is the goal of most of the programs discussed in the following reports. That is the goal of many sanitation and water quality experts. But the general public has other goals: avoiding the waste and the odors it can produce.There is a natural aversion to fecal matter and anything associated with it. Conflicts arise when experts propose recycling this “waste,” usually in a treated and tested form commonly called “biosolids,” back to soils in communities.

Managing excreta and wastewater sludge to produce recyclable biosolids involves many technical challenges. But equally significant are these social, cultural, and political challenges. Funding is required to build infrastructure – and, around the world, the public is the source of funding, either through taxes or sewer usage fees. In order for proper sanitation to be built and operated, complex community sanitation agencies with support from state, provincial, and national governments are needed.

Wastewater quality indicators are laboratory tests to assess suitability of wastewater for disposal or re-use. Tests selected and desired test results vary with the intended use or discharge location. Tests measure physical, chemical, and biological characteristics of the wastewater.

Physical characteristics

Temperature
Aquatic organisms cannot survive outside of specific temperature ranges. Irrigation runoff and water cooling of power stations may elevate temperatures above the acceptable range for some species. Temperature may be measured with a calibrated thermometer.

Solids
Solid material in wastewater may be dissolved, suspended, or settleable. Total dissolved solids or TDS (sometimes called filtrable residue) is measured as the mass of residue remaining when a measured volume of filtered water is evaporated. The mass of dried solids remaining on the filter is called total suspended solids (TSS) or nonfiltrable residue. Settleable solids are measured as the visible volume accumulated at the bottom of an Imhoff cone after water has settled for one hour. Turbidity is a measure of the light scattering ability of suspended matter in the water. Salinity measures water density or conductivity changes caused by dissolved materials.

Chemical characteristics
Virtually any chemical may be found in water, but routine testing is commonly limited to a few chemical elements of unique significance.

Hydrogen
Water ionizes into hydronium (H3O) cations and hydroxyl (OH) anions. The concentration of ionized hydrogen (as protonated water) is expressed as pH.

Oxygen
Most aquatic habitats are occupied by fish or other animals requiring certain minimum dissolved oxygen concentrations to survive. Dissolved oxygen concentrations may be measured directly in wastewater, but the amount of oxygen potentially required by other chemicals in the wastewater is termed an oxygen demand. Dissolved or suspended oxidizable organic material in wastewater will be used as a food source. Finely divided material is readily available to microorganisms whose populations will increase to digest the amount of food available. Digestion of this food requires oxygen, so the oxygen content of the water will ultimately be decreased by the amount required to digest the dissolved or suspended food. Oxygen concentrations may fall below the minimum required by aquatic animals if the rate of oxygen utilization exceeds replacement by atmospheric oxygen.

The reaction for biochemical oxidation may be written as:
Oxidizable material + bacteria + nutrient + O2 → CO2 + H2O + oxidized inorganics such as NO3 or SO4
Oxygen consumption by reducing chemicals such as sulfides and nitrites is typified as follows:

S– + 2 O2 → SO4–
NO2- + ½ O2 → NO3-

Since all natural waterways contain bacteria and nutrient, almost any waste compounds introduced into such waterways will initiate biochemical reactions (such as shown above). Those biochemical reactions create what is measured in the laboratory as the biochemical oxygen demand (BOD).

Oxidizable chemicals (such as reducing chemicals) introduced into a natural water will similarly initiate chemical reactions (such as shown above). Those chemical reactions create what is measured in the laboratory as the chemical oxygen demand (COD).

Both the BOD and COD tests are a measure of the relative oxygen-depletion effect of a waste contaminant. Both have been widely adopted as a measure of pollution effect. The BOD test measures the oxygen demand of biodegradable pollutants whereas the COD test measures the oxygen demand of biogradable pollutants plus the oxygen demand of non-biodegradable oxidizable pollutants.

The so-called 5-day BOD measures the amount of oxygen consumed by biochemical oxidation of waste contaminants in a 5-day period. The total amount of oxygen consumed when the biochemical reaction is allowed to proceed to completion is called the Ultimate BOD. The Ultimate BOD is too time consuming, so the 5-day BOD has almost universally been adopted as a measure of relative pollution effect.
There are also many different COD tests. Perhaps, the most common is the 4-hour COD.

There is no generalized correlation between the 5-day BOD and the Ultimate BOD. Likewise, there is no generalized correlation between BOD and COD. It is possible to develop such correlations for a specific waste contaminant in a specific wastewater stream, but such correlations cannot be generalized for use with any other waste contaminants or wastewater streams.

The laboratory test procedures for the determining the above oxygen demands are detailed in the following sections of the “Standard Methods For the Examination Of Water and Wastewater” available at www.standardmethods.org:

5-day BOD and Ultimate BOD: Sections 5210B and 5210C
COD: Section 5220

Nitrogen
Nitrogen is an important nutrient for plant and animal growth. Atmospheric nitrogen is less biologically available than dissolved nitrogen in the form of ammonia and nitrates. Availability of dissolved nitrogen may contribute to algal blooms. Ammonia and organic forms of nitrogen are often measured as Total Kjeldahl Nitrogen, and analysis for inorganic forms of nitrogen may be performed for more accurate estimates of total nitrogen content.

Chlorine
Chlorine has been widely used for bleaching, as a disinfectant, and for biofouling prevention in water cooling systems. Remaining concentrations of oxidizing hypochlorous acid and hypochlorite ions may be measured as chlorine residual to estimate effectiveness of disinfection or to demonstrate safety for discharge to aquatic ecosystems.

Biological characteristics
Water may be tested by a bioassay comparing survival of an aquatic test species in the wastewater in comparison to water from some other source. Water may also be evaluated to determine the approximate biological population of the wastewater. Pathogenic micro-organisms using water as a means of moving from one host to another may be present in sewage. Coliform index measures the population of an organism commonly found in the intestines of warm-blooded animals as an indicator of the possible presence of other intestinal pathogens.

Myron L Meters is the premier online retailer of the Myron L meters preferred by water professionals, like the Ultrameter III 9PTKA.

Information shared via Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0), original material found here:

https://www.boundless.com/microbiology/industrial-microbiology/wastewater-treatment-and-water-purification/wastewater-and-sewage-treatment/

https://en.wikipedia.org/wiki/Sewage_treatment

http://www.iwawaterwiki.org/xwiki/bin/view/Articles/GLOBALATLASOFEXCRETAWASTEWATERSLUDGEANDBIOSOLIDSMANAGEMENTMOVINGFORWARDTHESUSTAINABLEANDWELCOMEUSESOFAGLOBALRESOURCE

 

Categories : Case Studies & Application Stories, Science and Industry Updates

Electrical Conductivity Testing Applied to the Assessment of Freshly Collected Kielmeyera coriacea Mart. Seeds: MyronLMeters.com

Posted by 4 Jun, 2013

Tweet  MyronLMeters.com brings you the latest in conductivity measurement research like the article below.  Please click here for accurate, reliable, conductivity meters. Abstract Assessment of seed vigor has long been an important tool of seed quality control programs. The conductivity test is a promising method for assessment of seed vigor, but proper protocols for its […]

 

MyronLMeters.com brings you the latest in conductivity measurement research like the article below.  Please click here for accurate, reliable, conductivity meters.

Abstract

Assessment of seed vigor has long been an important tool of seed quality control programs. The conductivity test is a promising method for assessment of seed vigor, but proper protocols for its execution have yet to be established. The objective of this study was to assess the efficiency of electrical conductivity (EC) testing as a means of assessing the viability of freshly collected Kielmeyera Coriacea Mart. seeds. The test was performed on individual seeds rather than in a bulk configuration. Seeds were soaked for different periods (30 min, 90 min, 120 min., 180 min, and 240 min) at a constant temperature of 25°C. Conductivity was then measured with a benchtop EC meter.

1. Introduction

Seeds are the primary factor of the seedling production process, despite their minor contribution to the end cost of each seedling. In order to estimate the success rate of seedling production, it is essential that seed characteristics such as vigor and germinability be known [1].

The importance of knowing the characteristics of Brazilian forest species to safer and more objective management of seedling production cannot be overstated. However, such studies are scarce, particularly in light of the vast number of species with this potential [2]. Given the intensity of anthropogenic pressure and the importance of rehabilitating disrupted or degraded environments, in-depth research of forest species is warranted.

Routine methods used for determination of seed quality and viability include germination testing and the tetrazolium test. Methods such as measurement of soak solution pH, electrical conductivity, and potassium content of leachate, all based on the permeability of the cell membrane system, are increasingly being employed in the assessment of seed vigor, as they are reliable and fast and can thus speed the decision making process.

Electrical conductivity testing, as applied to forest seeds, has yet to be standardized. Studies conducted thus far have focused on assessment of seed soaking times, which may range from 4 to 48 hours. Even at 48 hours, the conductivity test is considered a rapid technique as compared to the germination test, which, despite its status as a widespread and firmly established method, can take anywhere from 30 to 360 days to yield results (depending on species), and is limited by factors such as dormant seeds.

The total concentration of electrolytes leached by seeds during soaking has long been assessed indirectly, mostly through the conductivity test, which takes advantage of the fact that inorganic ions make up a substantial portion of these electrolytes [3–5].

Rapid assessment of seed quality allows for preemptive decision-making during harvest, processing, sale and storage operations, thus optimizing use of financial resources throughout these processes.

K. coriacea Mart. is a species of the Clusiaceae (Guttiferae) family popularly known in Brazil as pau-santo (Portuguese for “holy wood”), due to its properties as a medicinal and melliferous plant and as a source of cork. In traditional Brazilian medicine, the leaves are used as an emollient and antitumor agent, and the resin as a tonic and in the treatment of toothache and various infections. The fruits are used in regional crafts and flower arrangements. Even if the dye is of the leaves and bark. The trunk provides cork [6].

K. coriaceae specimens grow to approximately 4 meters in height. The flowering period extends from January to April and the fruiting period from May to September, and seed collection can take place from September onwards. Leaves are alternate, simple, oval to elliptical, coriaceous, and clustered at the end of the branches, and feature highly visible, pink midribs. A white to off-white latex is secreted in small amounts upon removal of leaves. Flowers are white to pale pink in color, large, fragrant, with many yellow stamens and are borne in short clusters near the apex of the branches. Seedling production requires that seeds be sown shortly after collection.

In the fruit are found 60 to 80 seeds with anemochoric. The seed varies from round to oblong, winged at the ends, light brown color, has integument thin and fragile, with smooth texture, the sizes range from 4.3 to 5.6 cm long, 1.3 to 1.9 cm wide, and 0.2 to 0.5 centimeter thick. The individual weight of the seeds ranges from. 112 to.128 grams. Nursery radicle emission occurred at 7 days and the germination rate was 90%. Germination occurs within 7 to 10 days. The species is slow growing, both in the field and in a nursery setting [7].

The present study sought to assess the applicability of the conductivity test to freshly collected K. coriacea Mart. seeds by determining the optimal soak time for performance of the test and comparing results obtained with this method against those obtained by tetrazolium and germination testing of seeds from the same batch.

2. Materials and Methods

2.1. Seed Collection

Seeds were collected in the cerrado sensu stricto, in SCA (Clean Water Farm), area of study at the University of Brasília (UNB) in August 2010, matrixes marked with the aid of GPS, after the period of physiological maturation of the seeds. The collection of fruits was directly from the tree, with the help of trimmer, then the seeds were processed and stored in paper bags at room temperature in the laboratory.

2.2. Conductivity Test

The development of tests to evaluate the physiological quality of seeds, as well as the standardization of these is essential for the establishment of an efficient quality control [8]. One of the main requirements for the seed vigor refers to obtain reliable results in a relatively short period of time, allowing the speed of decision making especially as regards the operations of collection, processing, and marketing [9]. The literature indicates that rapid tests are most studied early events related to the deterioration of the sequence proposed by Delouche and Baskin [10] as the degradation of cell membranes and reduced activity, and biosynthetic respiratory [9]. The measurement of electrical conductivity through the electrolyte amount released by soaking seeds in water has been applied by the individual method where each seed is a sample or more often, a sample of seed representative of a population (mass method). For this case, the results represent the average conductivity of a group of seeds, may a small amount of dead seeds affect the conductivity of a batch with many high-quality seed generating a read underestimated. To minimize this problem, we recommend choosing the seeds, excluding the damaged seeds.

The electrical conductivity is based on the principle that the deterioration process is the leaching of the cells of seeds soaked in water due to loss of integrity of cellular systems. Thus, low conductivity means a high-quality seed and high conductivity, that is, greater output seed leachate, suggests that less force [11].

The electrical conductivity is not yet widely used in Brazil, its use is restricted to activities related to research (Krzyzanowski et al., 1991). There are common jobs using this test to determine the physiological quality of tree seeds. However, it is a promising vigor test for possible standardization of the methodology, at least within a species. However, it is a promising vigor test for possible standardization of the methodology, at least within a species. However, there are factors which influence the conductivity values as the size, the initial water content, temperature and time of soaking, the number of seeds per sample, and genotype [12].

Five treatments were carried out to test the efficiency of the conductivity test as a means of evaluating the viability of freshly collected K. coriacea Mart. seeds.

Five runs of 20 seeds were tested for each treatment. Seeds were individually placed into containers holding 50 mL of distilled water and left to soak for 30, 90, 120, 180, and 240 minutes in a germination chamber set to a constant temperature of 25°C. The minimum time taken for the soaking of 30 minutes was adopted by the same authors and Amaral and peske [13], Fernandes et al. [14], and Matos [1] who concluded that the period of 30 minutes of soaking is more effective to estimate the germination of the seeds. After each period, the conductivity of the soak solution was immediately tested with a benchtop EC meter precise to +/−1% (Quimis). Readings were expressed as μS·cm−1/g−1 seed [15].

Data thus obtained were subjected to analysis of variance with partitioning into orthogonal polynomials for analysis of the effect of soaking times on electrical conductivity.

2.3. Tetrazolium Test

The tetrazolium test, also known as biochemical test for vitality, is a technique used to estimate the viability and seed germination. A fundamental condition for ensuring the efficiency of the test is the direct contact of the tetrazolium solution with the tissues of the seed to be tested. Due to the impermeability of the coats of most forest tree seeds, it is necessary to adopt a previous preparation of the seeds that were tested. This preparation is based on facilitating entry of the solution in the seed. Among the preparations that precede the test we have cutting the seed coat, seed coat removal, scarification by sandpaper scarification by soaking in hot water and water [16]. In the previous preparation of the seeds, factors such as concentration of the solution or even the time of the staining solution can affect the efficiency of the test in the evaluation of seed quality. The time required for the development of appropriate color according to the Rules for Seed Analysis [16] varies depending on each species, can be between 30 and 240 minutes.

The tetrazolium test has been widely used in seeds of various species due to the speed and efficiency in the characterization of the viability and vigor, and the possibility of damage to the same distinction, assisting in the process of quality control from the steps of harvest storage (GRIS et al, 2007).

The tetrazolium test was also applied to freshly collected K. coriacea Mart. seeds, for a total of three runs and 20 seeds. Seeds were soaked in a 0.5% solution of 2,3,5-triphenyl-2H-tetrazolium for 24 hours in a germination chamber set to a constant temperature of 25°C. After each run, seeds were washed, bisected, and the half-containing the embryonic axis placed under a stereo viewer for examination of staining patterns [17].

2.4. Germination Test

The standard germination test is the official procedure to evaluate the ability of seeds to produce normal seedlings under favorable conditions in the field, but does not always reveal differences in quality and performance among seed lots, which can manifest in storage or in the field [18].

During the germination test optimum conditions are provided and controlled for seeds to encourage the resumption of metabolic activity which will result in the seedlings. The main objective of the germination test is the information about the quality of seeds, which is used in the identification of lots for storage and sowing [19].

Freshly collected K. coriacea Mart. seeds were placed in a germination chamber at a constant temperature of 25°C (Treatment 1) or an alternating temperature of 20–30°C (Treatment 2), on a standard cycle of 8 hours of light and 16 hours of dark. Each test consisted of five runs and was performed on 20 seeds.

Germination was defined as emergence of at least 2.0 mm of the primary root [20]. Assessment was conducted daily, and emergence was observed between day 6 and day 7. At the end of the 14-day test period, the germination percentage was calculated on the basis of radicle emergence [21].

Capture

3. Results

3.1. Conductivity Test

Different soaking times were not associated with any significant differences in conductivity results in K. coriacea Mart. seeds (Table 1).

Table 1: Conductivity ranges of freshly collected Kielmeyera coriacea Mart. seeds after soaking for different periods.
Seeds with a leachate conductivity range of 7–17.99 μS·cm·g were considered nonviable, confirming the hypothesis behind conductivity testing, which is the nonviable seeds that have higher soaking solution conductivity values (Table 2).

Table 2: Percentage of viable Kielmeyera coriacea Mart. seeds according to EC range.
Analysis of variance revealed a low coefficient of variation (20.26%), which suggests good experimental control (Table 3).

Table 3: Analysis of variance of various soaking times for electrical conductivity testing of Kielmeyera coriacea Mart. seeds.
After analysis of variance, the correlation between the soaking time and electrical conductivity variables was assessed. The cubic model yielded

Capture

which is indicative of a positive correlation between the study variables.

The following equation was obtained on the basis of the cubic model:

Capture

 

Analysis of a plot of the above function in the GeoGebra 2007 software package shows that variation in electrical conductivity as a function of soaking time is minor and approaches a constant, which is consistent with the study results, in which changes in soaking time had no influence on conductivity (Figure 1).

378139.fig.001
Figure 1: Leachate conductivity as a function of soaking time in Kielmeyera coriaceaMart. seeds.

Matos [1] reported that a 30-minute soak was enough for assessment of Anadenanthera falcata, Copaifera langsdorffii, and Enterolobium contortisiliquum seeds by the soaking solution pH method—that is, the amount of matter leached after this period sufficed for measurement.

Although the principle of conductivity is the same used for the test pH of exudate, the soaking time needed to analyze the differential seeds through the conductivity may be explained by the fact that this technique is quantitative, while pH in the art exudate analyzes are qualitative. In other words to the technique of pH values of the exudate it is important to detect the acidity of imbibition while on the electrical conductivity we draw a comparison between the analyzed values to separate viable from nonviable samples. To determine a value of electrical conductivity as a reference to determine viable seeds are to be considered the values obtained for fresh seeds and seeds stored.

The thickness of the K. coriacea Mart. seed coat may also have affected the soaking procedure; this species has very thin seed coats, which makes soaking a very fast process.

These results are consistent with those reported by Rodrigues [22], who subjected stored K. coriaceaMart. seeds to the conductivity test and found that 90 minutes is an appropriate soaking time for analysis.

Therefore, it can be inferred that for seed Kielmeyera coriacea Mart. the soaking time of 90 minutes can be applied to obtain satisfactory results.

3.2. Tetrazolium Test

Table 4 shows the results of tetrazolium testing of K. coriacea Mart. seeds in our sample. The mean viability rate was 96.6%. The testing procedure was based on Brazilian Ministry of Agriculture recommendations [17].

tab4
Table 4: Tetrazolium testing of Kielmeyera coriacea Mart. seeds.

The results of the tetrazolium test were quite similar to those obtained with the conductivity method, thus confirming the efficiency of the latter method as a means for assessing the viability of K. coriaceaMart. seeds.

3.3. Germination Test

The germination test results of freshly collected K. coriacea Mart. seeds are shown in Table 5. Regardless of temperature, both test batches exhibited good viability, and no seed dormancy was detected.

tab5
Table 5: Germination test results of Kielmeyera coriacea Mart. seeds.

Radicle emergence was observed between day 7 and day 9 of the test, according to the analysis criteria proposed by Labouriau [21].

These findings are consistent with those of Melo et al., [23] who reported high and relatively rapid germination rates for K. coriacea seeds kept at 25°C on paper towels, with emergence of a perfect radicle on the 7th day of assessment.

4. Conclusions

The electrical conductivity can be used as an indicator of seed viability and presents two advantages: to provide rapid and reliable results and the technique is not destructive and can use the seeds after the conductivity test, so they can be used to produce seedlings.

The present study showed that different soaking times had no effect on the results of conductivity testing of freshly collected K. coriacea Mart. seeds, suggesting that the amount of leached matter was never below the threshold required for adequate testing.

Electrical conductivity testing proved to be a feasible option for viability testing of K. coriacea Mart. seeds, as the results obtained with conductivity testing were confirmed by germination testing and by the tetrazolium test.

References

  1. J. M. M. Matos, Evaluation of pH test on exudate check feasibility of forest seeds, dissertation, University of Brasília, Brasília, Brazil, 2009.
  2. F. Poggiani, S. Bruni, and E. S. Q. Barbos, “Effect of shading on seedling growth of three species forest,” in National conference on native plants, vol. 2, pp. 564–569, Institute of Forestry, 1992.
  3. M. B. Mcdonald Jr. and D. O. Wilson, “ASA-610 ability to detect changes in soybean seed quality,” Journal of Seed Technology, vol. 5, no. 1, pp. 56–66, 1980.
  4. S. Matthews and A. Powell, “A eletrical conductivity test,” in Handbook of Vigor Test Methods, D. A. Perry, Ed., pp. 37–42, International Seed Testing Associaty, Zurich, Switzerland, 1981.
  5. J. Son Mark, W. R. Singh, A. D. C. Novembre, and H. M. C. P. Chamma, “Comparative studies to evaluate dem’etodos physiological quality of soybean seeds, with emphasis the electrical conductivity test,” Brazilian Journal of Agricultural Research, vol. 25, no. 12, pp. 1805–1815, 1990.
  6. S. R. Singh, A. P. Silva, C. B. Munhoz, et al., Guide of Cerrado Plants Used in the Chapada Veadeiros, WWF-Brazil, Brasilia, Brazil, 2001.
  7. J. M. Felfili, C. W. Fagg, J. C. S. Silva, et al., Plants of the APA Gama Cabeça de Veado: Species, ecosystems and recovery, University of Brasilia, Brasília, Department of Engineering Forest, Brasília, Brazil, 2002.
  8. M. F. B. Muniz, et al., “Comparison of methods for evaluating the physiological and health quality of melon seeds,” Journal of Seeds, Pellets, vol. 26, no. 2, pp. 144–149, 2004.
  9. D. C. F. S. Dias and J. Marcos Filho, “Electrical conductivity to assess seed vigor of soybean (Glycine max (L.) Merrill),” Scientia Agricola, vol. 53, no. 1, Article ID article id, pp. 31–42, 1996.View at Publisher · View at Google Scholar
  10. J. C. Delouche and C. C. Baskin, “Acelerated aging techniques for predicting the relative storability of seed lots,” Seed Science and Technology, vol. 1, no. 2, pp. 427–452, 1973.
  11. R. D. Vieira and F. C. Krzyzanowski, “Electrical conductivity test,” in Seed Vigor: Concepts and Tests, F. C. Krzyzanowski, R. D. Vieira, and J. B. França Neto, Eds., pp. 4.1–4.26, Abrates, London, UK, 1999.
  12. R. D. Vieira, “Electrical conductivity test,” in Seed Vigor Tests, R. D. Vieira and N. M. Carvalho, Eds., p. 103, FUNEP, Jaboticabal, Brazil, 1994.
  13. A. S. Amaral and S. T. Peske, “Exudate pH to estimate, in 30 minutes seed viability of soybeans,”Journal of seeds, vol. 6, no. 3, pp. 85–92, 1984.
  14. E. J. Fernandes, R. Sader, and N. M. Carvalho, “seed viability beans (Phaseolus vulgaris L.) estimated by the pH of the exudate,” in Congress Brazil’s Seeds, Gramado, Brazil, 1987.
  15. F. C. Krzyzanowski and R. D. Vieira, “Electrical conductivity test,” in Seed Vigor: Concepts and Tests, F. C. Krzyzanowski, R. D. Vieira, and J. B. France Neto, Eds., pp. 4.1–4.26, Abrates, London, UK, 1999.
  16. Ministry of Agriculture, Livestock and Supply, Rule for seed testing, SNPA/DNPV/CLAV, Brasilia, Brazil, 1992.
  17. Ministry of Agriculture, Livestock and Supply, Rule for seed testing, SNPA/DNPV/CLAV, Brasilia, Brazil, 2009.
  18. N. M. Carvalho and J. Nakagawa, Seeds: Science, Technology and Production, FUNEP, Jaboticabal, Brazil, 2000.
  19. Pina-Rodrigues, et al., “Quality test,” in Germination from Basic to Applied, A. Ferreira and G. F. Borghetti, Eds., pp. 283–297, 2004.
  20. A. G. Ferreira and F. Borghetti, from basic to Germination applied, Artmed, Porto Alegre, Brazil, 2004.
  21. L. G. Labouriau, seed germination, OAS, Washington, DC, USA, 1983.
  22. L. L. Rodrigues, Study of imbibition time for application the method of electrical conductivity in the verification of the feasibility forest seeds stored, monograph, University of Brasília, Brasília, Brazil, 2010.
  23. J. T. Melo, J. F. Ribeiro, and V. L. G. F. Lima, “Germination of Seeds of some tree species native to the Cerrado,” Journal of Seeds, vol. 1, no. 2, pp. 8–12, 1979.

Research article by: Kennya Mara Oliveira Ramos,1 Juliana M. M. Matos,1 Rosana C. C. Martins,1 and Ildeu S. Martins2

1Seed Technology Laboratory of Forestry, Department of Forestry, University of Brasilia, CP 04357, 70919970 Campus Asa Norte, DF, Brazil
2Department of Forestry, University of Brasilia, CP 04357, 70919970 Campus Asa Norte, DF, Brazil

Received 17 December 2011; Accepted 14 February 2012

Academic Editors: A. Berville, C. Gisbert, J. Hatfield, and Y. Ito

Copyright © 2012 Kennya Mara Oliveira Ramos et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

 

Categories : Case Studies & Application Stories, Science and Industry Updates

Conductivity as a Function of Location – MyronLMeters.com

Posted by 26 May, 2013

TweetHypothesis: Does the time of year affect the conductivity of stagnant water in a given location? Abstract: We decided to test the conductivity levels of the water at Flat Rock Brook. If the conductivity levels are higher, it might imply higher total dissolved solid levels. We would like to see if the conductivity level changes during seasons […]

Hypothesis: Does the time of year affect the conductivity of stagnant water in a given location? Abstract: We decided to test the conductivity levels of the water at Flat Rock Brook. If the conductivity levels are higher, it might imply higher total dissolved solid levels. We would like to see if the conductivity level changes during seasons with snowfall versus seasons without snowfall. Background:

  • Independent Variable: Time of Year (Season)
  • Independent Variable: Location
  • Dependent Variable: Conductivity Level (mg/L TDS)

The purpose of the experiment is to test the change in conductivity level throughout the year (on a seasonal basis) in various locations. While doing this experiment, it is important to keep in mind these three things:

  1. How does conductivity vary at any of the given sites during a given season.(1)
  2. What human influence might have an impact on the conductivity of the water at any given part of the year.(1)
  3. Why might this change affect the ability of organisms to live in the given test sites.(1)

This is important to Flat Rock Brook because the data could be used to do several things. For example, the change in conductivity may change the organic life in the water, thus changing the ability to safely drink it. The change may impact the ability of organisms to grow in the water, and it may change the reactive nature of the water. Conductivity can be measured by the total dissolved solids in the water. Total Dissolves Solids include the number of mineral and salt impurities in the water. (1) Ultimately, the number of minerals and salts determines how many ions in mg/L. The impurities in the water can include runoff from roads, wastewater from industrial plants, and soils and rocks. (1) The amount of total dissolved solids in the water can have a physiological effect on plants and animals living in the ponds. (2) Conductivity can be used as a way of noting changes in water conditions over short periods of time. (2) Also, the level of total dissolved solvents in water can have an effect of the ability of habitat-forming plants to grow, thus disrupting the presence of certain species. (2) Materials:

  • GPS Navigator by Magellan: We used the GPS as a way to mark off specific testing sites at McFadden’s Pond and Quarry Pond, in order to test in a precise and consistent location
  • pH/Conductivity Probe: We used the pH/Conductivity Probe to test the level of conductivity in the various locations. The conductivity was measured in mg/L (TDS), and microsiemens (µS), but due to the difficult nature of working with microsiemens, we chose to work primarily with mg/L(TDS).
  • Distilled Water: We used the distilled water to wash off the probe in between tests in order to maintain accurate readings without tainted results.
  • Map of Flat Rock Brook: We used the map of Flat Rock Brook in order to find locations from which we could test conductivity levels of water.
  • Vernier conductivity probe used with a Lab Pro interface: We used this for our May data in order to get a more accurate reading. By taking samples from Flat Rock Brook, we connected this probe to Logger Pro and recorded the conductivity which was also measured in TDS. NOTE: We used the conductivity data from these readings in our graphs and overall analysis because it provided a more accurate measurement

 

 

 

 

 

 

 

 

 

 

 

 

Methods: *Adapted from Electrical Conductivity Protocol Used by University Corporation for Atmospheric Research, Colorado State University, and NASA. (Water Temperature was not recorded.)

  • Record water temperature
  • Pour water sample into two containers (or measure in water body)
  • Rinse electrodes with distilled water, blot dry
  • Place meter in first container, 2-3 seconds
  • Remove meter, shake gently, and place in second

container, 1 minute (Do not rinse with distilled water)

  • Record value when stabilized
  • Repeat measurement with new sample water, twice
  • Average three measurements and check for accuracy

Original Protocol can be found at this link*: http://72.14.205.104/search?q=cache:tpTXJUjpiHgJ:globe.ucar.edu/trr-

 

Cleaning off the conductivity probe before testing the water. (Figure 2)

 

Testing the conductivity of the pond (Figure 3)

 

Results: Fall (November) : -Quarry Pond:

  • .9 mg/L

-McFadden’s Pond (site A)*:

  • 3.1 mg/L

-McFadden’s Pond (site B)*:

  • 3.05 mg/L

Spring (May): (with ph/conductivity probe) -Quarry Pond:

  • .83 mg/L

-McFadden’s Pond (Site A):

  • 2.95 mg/L

-McFadden’s Pond (Site B):

  • 2.02 mg/L

Spring (May): (LoggerPro Data) -Quarry Pond:

  • .8 mg/L

-McFadden’s Pond (Site A):

  • 3.1 mg/L

-McFadden’s Pond (Site B):

  • 2.1 mg/L

Data Graph for Quarry Pond (Figure 4)

Data Graph for McFadden’s Pond Site A (Figure 5)

Data Graph for McFadden’s Pond Site B (Figure 6)

Data Graph for all three locations (Figure 7)

 

Discussion: Throughout our research, there was a general shift in the conductivity level in each site we tested. At Quarry Pond, the total dissolved solids reduced from .9 mg/L to .8 mg/L from November to May. This shift can be seen in the graph shown in Figure 4. McFadden’s Pond Site B also showed a substantial shift between the November and May readings, from 3.05 mg/L to 2.1 mg/L, as seen in Figure 6. Despite these significant changes, Site A at McFadden’s Pond did not change. This could potentially be due to its close proximity to moving water. A subtle, unnoticed under-current may have existed which may have caused the water to be mixed, and therefore diluted. The figures for this measurement can be seen in Figure 5.

The changes in conductivity at Quarry Pond may be the result of runoff from the parking lot and the roads in close proximity to it. Quarry Pond, unlike the other locations was close enough to a road that run-off affects the level of total dissolved solids. Although there was a significant change in conductivity between readings, the total dissolved solids were much lower than that of McFadden’s Pond. This may explain why the presence of algae was much higher in Quarry Pond than in McFadden’s Pond. McFadden’s Pond’s conductivity may have been higher due to a larger level of mineral deposits from soil runoff. One possible explanation for this shift in conductivity is the dilution of total dissolved solids in pond water due to rainfall and melting water from snow.

Conclusion: When comparing conductivity of water at a given point of time during the year, it is clear that there are noticeable differences. During the Fall and Winter, when there is more soil and road runoff, the conductivity level is higher. Conversely, during the spring, when there is more rainwater and melted snow and ice to dilute the ponds, the conductivity level drops. This would suggest that during fall and winter, the conditions of the pond are noticeably different. This suggests the possibility that there may be a shift in population from one group of organisms to another on a seasonal basis. Knowledge of these changes may help to explain why animals would migrate to a different habitat during different seasons. Because of the nature of soil runoff and road runoff, the level of Total Dissolved Solids in the water changes on a seasonal basis, and with that, the conductivity changes as well. In conclusion, conductivity does change over time of year in stagnant water, primarily because of external conditions such as runoff and wastewater.

References:

(1)The GLOBE Program, “Electrical Conductivity Protocol.” Hydro-Electrical Conductivity. Ed. UCAR, Colorado State University, NASA.

<[[http://72.14.205.104/search?q=cache:tpTXJUjpiHgJ:globe.ucar.edu/trr-ppt/HydroElecCond.ppt+Testing+Level+of+Conductivity+of+water+site:.edu&hl=en&ct=clnk&cd=9&gl=us&client=firefox-a%3Cspan%3C/span%3E%3Cspan|http://72.14.205.104/search?q=cache:tpTXJUjpiHgJ:globe.ucar.edu/trr-ppt/HydroElecCond.ppt+Testing+Level+of+Conductivity+of+water+site:.edu&hl=en&ct=clnk&cd=9&gl=us&client=firefox-a<span<span]]

We used the Power Point file linked to this page as our primary source of background information as well as a standard protocol for our field tests.

(2)Conductivity And Water Quality.

<[[http://kywater.org/ww/ramp/rmcond.htm%3C/span%3E%3Cspan|http://kywater.org/ww/ramp/rmcond.htm<span]] We used this website as our second source of data for finding out environmental impacts of change in conductivity and overall water quality. (Note: No Author, Publisher or Editor could be found for this web page.) __ *Site A is to the right of Mystery Bridge *Site B is to the left of Mystery Bridge *Note, this protocol was implemented both in the field and in a lab dependent on the time the data was collected *If the web page is difficult to view, a link to a .ppt file is available at the top of the page. The protocol can be found on slide #12.

Study authors: Margot Bennett and Rob Schwartz

Contributions to http://d-e-science11.wikispaces.com/ are licensed under a Creative Commons Attribution Share-Alike 3.0 License

 

Categories : Case Studies & Application Stories, Science and Industry Updates

Water Quality Testing in RO Systems – MyronLMeters.com

Posted by 10 May, 2013

Tweet Water quality testing is vital to the design of an efficient, cost-effective RO system, and is one of the best ways to preserve system life and performance. Using an accurate Total Dissolved Solids (TDS) measurement to assess the system load prevents costly mistakes up front. The TDS measurement gives users the information they need […]

DH-UMIII-9PTK-2T

Water quality testing is vital to the design of an efficient, cost-effective RO system, and is one of the best ways to preserve system life and performance.

Using an accurate Total Dissolved Solids (TDS) measurement to assess the system load prevents costly mistakes up front. The TDS measurement gives users the information they need to determine whether or not pretreatment is required and the type of membrane/s to select. Ultrameter™ and ULTRAPEN PT1™ Series TDS instruments feature the unique ability to select from 3 industry standard solution models: 442 Natural Water™ NaCl; and KCl. Choosing the model that most closely matches the characteristics of source water yields measurements accurate enough to check and calibrate TDS monitor/controllers that can help alert to system failures, reducing downtime and increasing productivity. The same instruments provide a fast and accurate test for permeate TDS quality control. Measuring concentrate values and analyzing quality trends lets users accurately determine membrane usage according to the manufacturer’s specifications so they can budget consumption correctly. These daily measurements are invaluable in detecting problems with system performance where changes in the ionic concentration of post-filtration streams can indicate scaling or fouling. System maintenance is generally indicated if there is either a 10-15% drop in performance or permeate quality as measured by TDS.

Thin-film composite membranes degrade when exposed to chlorine. In systems where chlorine is used for microbiological control, the chlorine is usually removed by carbon adsorption or sodium bisulfite addition before membrane filtration. The presence of any chlorine in such systems will at best reduce the life of the membrane, thus, a target of 0 ppm free chlorine in the feedwater is desirable.

ORP gives the operator the total picture of all chemicals in solution that have oxidizing or reducing potential including chlorine, bromine, chloramines, chlorine dioxide, peracetic acid, iodine, ozone, etc. However, ORP can be used to monitor and control free chlorine in systems where chlorine is the only sanitizer used. ORP over +300 mV is generally considered undesirable for membranes. Check manufacturer’s specifications for tolerable ORP levels.

An inline ORP monitor/controller placed ahead of the RO unit to automatically monitor for trends and breakthroughs coupled with spot checks by a portable instrument will prevent equipment damage and failure. Myron L 720 Series II™ ORP monitor/controllers can be configured with bleed and feed switches as well as visible and audible alarms.

Ultrameter and ULTRAPEN portable handhelds are designed for fast field testing and are accurate enough to calibrate monitor/controllers. Our measurement methods are objective and have superior accuracy and convenience when compared to colorimetric methods where determination of equivalence points is subjective and can be skewed by colored or turbid solutions.

Monitoring pH of the source water will allow users to make adjustments that optimize the performance of antiscalants, corrosion inhibitors and anti-foulants. Using a 720 II Series Monitor/controller to maintain pH along with an Ultrameter Series or ULTRAPEN PT2™ handheld to spot check pH values will reduce consumption of costly chemicals and ensure their efficacy.

Most antiscalants used in chemical system maintenance specify a Langelier Saturation Index maximum value. Some chemical manufacturers and control systems develop their own proprietary methods for determining a saturation index based on solubility constants in a defined system. However, LSI is still used as the predominant scaling indicator because calcium carbonate is present in most water. Using a portable Ultrameter III 9PTKA™ provides a simple method for determining LSI to ensure the chemical matches the application.

The Ultrameter III 9PTKA computes LSI from independent titrations of alkalinity and hardness along with electrometric measurements of pH and temperature. Using the 9PTKA LSI calculator, alterations to the water chemistry can be determined to achieve the desired LSI. Usually, pH is the most practical adjustment. If above 7, acid additions are made to achieve the pH value in the target LSI. Injections are made well ahead of the RO unit to ensure proper mixing and avoid pH hotspots. A Myron L 720 Series II pH Monitor/controller will automatically detect and divert solution with pH outside the range of tolerance for the RO unit. ULTRAPEN PT2, TechPro II and Ultrameter Series instruments can be used to spot check and calibrate the monitor/controller as part of routine maintenance and to ensure uniform mixing.

Water hardness values indicate whether or not ion exchange beds are required in pretreatment. Checking hardness values directly after the softening process with the Ultrameter III 9PTKA ensures proper functioning and anticipates the regeneration schedule.

Alkalinity is not only important in its effect on the scaling tendency of solution, but on pH maintenance. Additions of lime are used to buffer pH during acid injection. Use a 9PTKA to measure alkalinity values for fast field analysis where other instrumentation is too cumbersome to be practical.

Though testing and monitoring pressure is a good way to evaluate system requirements and performance over time, measuring other water quality parameters can help pinpoint problems when troubleshooting. For example, if the pressure differential increases over the second stage, the most likely cause is scaling by insoluble salts. This means that any degradation in performance is likely due to the dissolved solids in the feed. Using a 9PTKA to evaluate LSI and calculate parameter adjustments is a simple way to troubleshoot a costly problem.

Myron L Meters saves you 10% on all Ultrameters and Ultrapens when you order online at MyronLMeters.com, where you can find the complete selection of Myron L meters, including the Ultrameter III 9PTKA.

Original story from International Filtration News V 32, no. 2

 

Categories : Application Advice, Case Studies & Application Stories, Technical Tips

Pool Draining Tips to Protect Water Quality – MyronLMeters.com

Posted by 1 May, 2013

TweetMyronLMeters.com has the most advanced lineup of pool analysis meters for the professional pool maintenance technician from the Ultrapen to the PoolPro PS9. Pool Draining Tips to Protect Water Quality With summer right around the corner, many swimming pool owners will be readying their swimming pools in anticipation of the season’s heat. As part of […]

MyronLMeters.com has the most advanced lineup of pool analysis meters for the professional pool maintenance technician from the Ultrapen to the PoolPro PS9.

Pool Draining Tips to Protect Water Quality

With summer right around the corner, many swimming pool owners will be readying their swimming pools in anticipation of the season’s heat. As part of this process, some pool owners like to drain old swimming pool water which has been sitting all winter. Though not a necessary task, the following tips are provided for you to properly drain pool water in order to protect the water resources in your community.

Whenever possible, it is best to drain your pool onto your landscape. This recycles your pool water, conserves irrigation water, and avoids the environmental risks associated with draining your pool to the street. Before draining your pool water to the street or to your landscape, be sure to follow the guidelines outlined below.

While draining pool water to the street is a common practice, it can prove harmful to the environment if the pool owner does not properly plan and prepare prior to draining. When pool water is drained to the street, it can carry other pollutants such as oil, grease, sediment, bacteria and trash down the storm drain and into the nearest creek, river, or the ocean. Swimming pool water also often contains harmful additives and chemicals. If the water is not properly treated to remove these pollutants prior to draining, they can cause further damage to the health of our waterways and to the plants and animals that live there.

Also, prior to draining to the street, residents are asked to sweep the curb and gutter between the discharge point from their yard to the storm drain down hill from their home. This will remove any pollutants from the gutter that may be carried up by the drained pool water to the storm drain.

For chlorine pools, chlorine levels must be lowered to less than 1 part per million prior to draining. This can be done naturally, by simply allowing the pool water to sit in the sun for a minimum of three days. Alternatively, de-chlorination kits can be purchased at home supply stores at a very reasonable cost. These kits have the tools you need to reach the appropriate chlorine levels before draining your pool to the curb and gutter.

Some people have salt water pool systems which may be preferred due to the lower amount of chemicals required for their operation. However, these pools must not be drained to the storm drain system due to their high salt content relative to the fresh water systems they drain into. Total dissolved solids (TDS) must be below 500 parts per million in order to drain into the street.

Green pools,” which are pools in which algae is growing, also must not be drained to the street. In these instances, algae must first be killed and removed. This is usually done by chlorinating the swimming pool until the algae is gone, then lowering chlorine to the allowable discharge level. Cartridge filters or diatomaceous earth (DE) filters should be rinsed onto a pervious surface such as landscaped areas or grass. While DE is actually beneficial in your garden, it can build up in storm drains and clog them. DE residues can be scooped up and simply thrown in the trash or put to use fending off worms in your garden.

For more information on how to reach acceptable chemical and TDS levels, call your pool maintenance specialist.

If you are a pool maintenance specialist, consider the PoolPro PS9TKA from MyronLMeters.com – the most advanced and comprehensive pool water analysis meter on the market.

PS9TK from MyronLMeters.com

 

 

 

 

 

 

 

 

 

Pool Pro PS9TK

Measures 9 Parameters: Conductivity, Mineral/Salts, TDS, Alkalinity, Hardness, LSI, pH, ORP/Free Chlorine, Temperature
LSI Calculator for hypothetical water balance calculations
Wireless data transfer capability with bluDock option
Auto-ranging delivers increased resolution across diverse applications
Adjustable Temperature Compensation and Cond/TDS conversion ratios for user-defined solutions
Nonvolatile memory of up to 100 readings for stored data protection
Date & time stamp makes record-keeping easy
pH calibration prompts alert you when maintenance is required
Auto-off minimizes energy consumption
Low battery indicator
(Includes instrument with case and solutions)

Categories : Case Studies & Application Stories