Archive for August, 2013

FDA green washing antibiotic reductions | Avinash Kar’s Blog | Switchboard, from NRDC

Posted by 30 Aug, 2013

TweetFDA green washing antibiotic reductions | Avinash Kar’s Blog | Switchboard, from NRDC

FDA green washing antibiotic reductions | Avinash Kar’s Blog | Switchboard, from NRDC

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NIST Traceability Policy: MyronLMeters.com

Posted by 26 Aug, 2013

TweetAll Myron L meters are factory calibrated with NIST traceable Standard Solutions having specific conductivity/ppm values. MyronL Standard Solutions are made under strictly controlled conditions using reagent grade salts. These salts are mixed with deionized water having a resistivity of at least 5 megohms-cm purity. Myron L Standard Solutions have an accuracy of +1% based […]

All Myron L meters are factory calibrated with NIST traceable Standard Solutions having specific conductivity/ppm values. MyronL Standard Solutions are made under strictly controlled conditions using reagent grade salts. These salts are mixed with deionized water having a resistivity of at least 5 megohms-cm purity.

Myron L Standard Solutions have an accuracy of +1% based on values published in the International Critical Tables and traceable to the National Institute of Standards and Technology. NIST certificates , while not available on Ultrapens, are available on most other Myron L meters and solutions. Check the product page for the NIST certificate option. See example below:

NIST certificate option

NIST certificate option

 

 

 

 

 

Regular use of these solutions is recommended to ensure specified instrument accuracy. Frequency of conductivity recalibration depends upon use, but once every month should be sufficient for an instrument used daily. pH models, depending upon use, should be recalibrated with pH 7 Buffer every 1-2 weeks, and checked with pH 4 and/or 10 Buffers at similar intervals. pH Sensor Storage Solution is recommended for keeping the pH sensor hydrated. Myron L solutions are available in quart/1 ltr., gallon/3,8 ltr. and 2 oz./59 ml plastic bottles, ready to use.

Below is the official NIST traceability policy from the website of the National Institute of Standards and Technology.

Introduction

The mission of NIST is to promote U.S. innovation and industrial competitiveness by advancing measurement science, standards, and technology in ways that enhance economic security and improve our quality of life. To help meet the measurement and standards needs of U.S. industry and the nation, NIST provides calibrations, standard reference materials, standard reference data, test methods, proficiency evaluation materials1, measurement quality assurance programs, and laboratory accreditation services that assist a customer in establishing traceability of measurement results.

Metrological traceability requires the establishment of an unbroken chain of calibrations to specified references. NIST assures the traceability of measurement results that NIST itself provides, either directly or through an official NIST program or collaboration. Other organizations are responsible for establishing the traceability of their own results to those of NIST or other specified references. NIST has adopted this policy statement to document the NIST role with respect to traceability.

Statement of Policy
To support the conduct of its mission and to ensure that the use of its name, products, and services is consistent with its authority and responsibility, NIST adopts for its own use and recommends for use by others the definition of metrological traceability2 provided in the most recent version of the International Vocabulary of Metrology: “property of a measurement result whereby the result can be related to a reference through a documented unbroken chain of calibrations, each contributing to the measurement uncertainty.” (International Vocabulary of Metrology – Basic and General concepts and Associated Terms (VIM), definition 2.41, see Reference [1]).
To support the conduct of its mission and to ensure that the use of its name, products, and services is consistent with its authority and responsibility, NIST:

1. Adopts for its own use and recommends for use by others the definition of traceability provided in the most recent version of the International vocabulary of metrology – Basic and general concepts and associated terms (VIM): “property of a measurement result whereby the result can be related to a reference through a documented unbroken chain of calibrations, each contributing to the measurement uncertainty..” [1].
2. Establishes metrological traceability of the results of its own measurements and of results provided to customers in NISTcalibration and measurement certificates, operating in accordance with the NIST Quality System for Measurement Services.
3. Asserts that providing support for a claim of metrological traceability of the result of a measurement is the responsibility of theprovider of that result, whether that provider is NIST or another organization; and that assessing the validity of such a claim is the responsibility of the user of that result.
4. Communicates, especially where claims expressing or implying the contrary are made, that NIST does not define, specify,assure, or certify metrological traceability of the results of measurements except those that NIST itself provides, either directly or through an official NIST program or collaboration. (See also NIST Administrative Manual, Subchapter 5.03, NIST Policy on Use of its Name in Advertising.)
5. Collaborates on development of standard definitions, interpretations, and recommended practices with organizations that have authority and responsibility for variously defining, specifying, assuring, or certifying metrological traceability.
6. Develops and disseminates technical information on traceability and conducts coordinated outreach programs on issues of traceability and related requirements.
7. Assigns responsibility for oversight of implementation of the NIST policy on metrological traceability to the NIST Measurement Services Advisory Group (MSAG).

1 Underlined terms are defined in III Glossary of Terms in the Supplementary Materials section following.
2 The full term, “metrological traceability” is preferred when there is a risk of confusion with other meanings of the abbreviated term “traceability”, which is sometimes used to refer to the “history” or “trace” of an item. The abbreviated term is also used in this document to improve readability, since it is clear that “metrological traceability” is meant in every case.
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce. Original found here: http://www.nist.gov/traceability/nist_traceability_policy_external.cfm

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

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

Posted by 21 Aug, 2013

Tweet https://www.myronlmeters.com/ Save 10% on accurate, reliable, easy-to-use Myron L water quality meters at MyronLMeters.com.


Save 10% on accurate, reliable, easy-to-use Myron L water quality meters at MyronLMeters.com.

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Posted by 21 Aug, 2013

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Ultrapen PT1 – Product Overview Video

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Posted by 21 Aug, 2013

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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