Technical Tips

Frequently Asked Questions – MyronLMeters.com

Posted by 28 Jan, 2013

TweetHow long will my Standard Solutions and Buffers last? The warranty on all standards and buffers is one year from the date it is manufactured (see the label on the bottle). If the standards and buffers become contaminated by the user pouring test samples back into the bottle or inserting the probe into the bottle […]

How long will my Standard Solutions and Buffers last?

The warranty on all standards and buffers is one year from the date it is manufactured (see the label on the bottle). If the standards and buffers become contaminated by the user pouring test samples back into the bottle or inserting the probe into the bottle the solution will not be accurate and should be discarded. The life of standards and buffers can exceed 1 year if the bottle is stored tightly capped and is not exposed to direct sunlight or freezing temperatures. If the solution becomes frozen, do not remove the cap – allow the standard or buffer solution to thaw completely and shake the bottle vigorously before opening.

How do I clean the conductivity cell cup on the handheld units?

With everyday sampling, the cell cup may build up a residue or film on the cell walls that may cause the readings to become erratic. Use a 50/50 mixture of a common household cleaner (i.e. Lime-A-Way, CLR, Tilex, etc) and DI water. Pour into conductivity cell cup and scrub with a q-tip. Be sure to get around all the electrodes and the thermistor probe. On the DS handheld unit, use an acid brush to scrub the cell cup. Let it set for about 10 minutes. Rinse the cell cup thoroughly with tap water, then a final rinse with DI water.

The display on my Ultrameter II 6P reads “Error 1″. What does that mean?

This is possibly caused by contamination to the circuit board. One or more of the traces on the PCB have been jumped/bridged and there is a contamination. Possible moisture, condensation, dirt, dried salts or other condensation inside is a potential cause for this display.

Where can I get an operations manual for my meter?

Go to MyronLMeters.com. Click on Manuals and Literature at the top of the page. Once on the Manuals and Literature page, you’ll find application bulletins, operations manuals, material safety data sheets, and product datasheets.  All are free, downloadable pdf files.

How do I pick the correct range module for my Monitor or Monitor/Controller?

Pick a range module that covers 2/3 of your operating range. If you pick a range module that is too broad, then your accuracy will suffer or it will not show a number on the display. For example, if your operating range is 100-150 microsiemens, a range module of 0-200 microsiemens (-115) would be a good choice. A range module of 0- 5,000 microsiemens (-123) would not be a good choice for this application

Got questions? Visit us at MyronLMeters.com and Ask An Expert.

 

 

 

 

Categories : Application Advice, Care and Maintenance, Product Updates, Technical Tips

Reusing Greywater – MyronLMeters.com

Posted by 15 Dec, 2012

TweetGreywater is water from your bathroom sinks, showers, tubs, and washing machines. It is not water that has come into contact with feces, either from the toilet or from washing diapers. Greywater may contain traces of dirt, food, grease, hair, and certain household cleaning products. While greywater may look “dirty,” it is a safe and […]

Greywater is water from your bathroom sinks, showers, tubs, and washing machines. It is not water that has come into contact with feces, either from the toilet or from washing diapers.

Greywater may contain traces of dirt, food, grease, hair, and certain household cleaning products. While greywater may look “dirty,” it is a safe and even beneficial source of irrigation water in a yard. If released into rivers, lakes, or estuaries, the nutrients in greywater become pollutants, but to plants, they are valuable fertilizer. Aside from the obvious benefits of saving water (and money on your water bill), reusing your greywater keeps it out of the sewer or septic system, thereby reducing the chance that it will pollute local water bodies. Reusing greywater for irrigation reconnects urban residents and our backyard gardens to the natural water cycle.

The easiest way to use greywater is to pipe it directly outside and use it to water ornamental plants or fruit trees. Greywater can be used directly on vegetables as long as it doesn’t touch edible parts of the plants. In any greywater system, it is essential to put nothing toxic down the drain–no bleach, no dye, no bath salts, no cleanser, no shampoo with unpronounceable ingredients, and no products containing boron, which is toxic to plants. It is crucial to use all-natural, biodegradable soaps whose ingredients do not harm plants. Most powdered detergent, and some liquid detergent, is sodium based, but sodium can keep seeds from sprouting and destroy the structure of clay soils. Choose salt-free liquid soaps. While you’re at it, watch out for your own health: “natural” body products often contain substances toxic to humans, including parabens, stearalkonium chloride, phenoxyethanol, polyethelene glycol (PEG), and synthetic fragrances.

For residential greywater systems simple designs are best. With simple systems you are not able to send greywater into an existing drip irrigation system, but must shape your landscape to allow water to infiltrate the soil. We recommend simple, low-tech systems that use gravity instead of pumps. We prefer irrigation systems that are designed to avoid clogging, rather than relying on filters and drip irrigation.

Greywater reuse can increase the productivity of sustainable backyard ecosystems that produce food, clean water, and shelter wildlife. Such systems recover valuable “waste” products–greywater, household compost, and humanure–and reconnect their human inhabitants to ecological cycles. Appropriate technologies for food production, water, and sanitation in the industrialized world can replace the cultural misconception of “wastewater” with the possibility of a life-generating water culture.

More complex systems are best suited for multi-family, commercial, and industrial scale systems. These systems can treat and reuse large volumes of water, and play a role in water conservation in dense urban housing developments, food processing and manufacturing facilities, schools, universities, and public buildings. Because complex systems rely on pumps and filtration systems, they are often designed by an engineer, are expensive to install and may require regular maintenance.

Basic Greywater Guidelines

Greywater is different from fresh water and requires different guidelines for it to be reused.
1. Don’t store greywater (more than 24 hours). If you store greywater the nutrients in it will start to break down, creating bad odors.
2. Minimize contact with greywater. Greywater could potentially contain a pathogen if an infected person’s feces got into the water, so your system should be designed for the water to soak into the ground and not be available for people or animals to drink.
3. Infiltrate greywater into the ground, don’t allow it to pool up or run off (knowing how well water drains into your soil (or the soil percolation rate of your soil) will help with proper design. Pooling greywater can provide mosquito breeding grounds, as well as a place for human contact with greywater.
4. Keep your system as simple as possible, avoid pumps, avoid filters that need upkeep. Simple systems last longer, require less maintenance, require less energy and cost less money.
5. Install a 3-way valve for easy switching between the greywater system and the sewer/septic.
6. Match the amount of greywater your plants will receive with their irrigation needs.

Types of simple systems

From the Washing Machine

Washing machines are typically the easiest source of greywater to reuse because greywater can be diverted without cutting into existing plumbing. Each machine has an internal pump that automatically pumps out the water- you can use that to your advantage to pump the greywater directly to your plants.

Laundry Drum

Drum should be strapped to wall for safety.

 

 

 

 

 

 

An example of a laundry drum system.

If you don’t want  to invest much money in the system (maybe you are a renter), or have a lot of hardscape (concrete/patio) between your house and the area to irrigate, try a laundry drum system.

Wash water is pumped into a “drum,” a large barrel or temporary storage called a surge tank. At the bottom of the drum the water drains out into a hose that is moved around the yard to irrigate. This is the cheapest and easiest system to install, but requires constant moving of the hose for it to be effective at irrigating.

Laundry to Landscape (aka drumless laundry)

The laundry to landscape system gives you flexibility in what plants you’re able irrigate and takes very little maintenance.

In this system, the hose leaving the washing machine is attached to a valve that allows for easy switching between the greywater system and the sewer. The greywater goes to 1″ irrigation line with outlets sending water to specific plants. This system is low cost, easy to install, and gives huge flexibility for irrigation. In most situations this is the number one place to start when choosing a greywater system.

From the Shower

Showers are a great source of greywater- they usually produce a lot of relatively clean water. To have a simple, effective shower system you will want a gravity-based system (no pump). If your yard is located uphill from the house, then you’ll need to have a pumped system.

Branched Drain:

Greywater in this system flows through standard (1 1/2″ size) drainage pipe, by gravity, always sloping downward at 2% slope, or 1/4 inch drop for every foot traveled horizontally, and the water is divided up into smaller and smaller quantities using a plumbing fitting that splits the flow. The final outlet of each branch flows into a mulched basin, usually to irrigate the root zone of trees or other large perennials. Branched drain systems are time consuming to install, but once finished require very little maintenance and work well for the long term.

 

 

 

 

 

An example of a branched drain system .

From the Sinks

Kitchen sinks are the source of a fair amount of water, usually very high in organic matter (food, grease, etc.). Kitchen sinks are not allowed under many greywater codes, but are allowed in some states, like Montana. This water will clog many kinds of systems. To avoid clogging, we recommend branched drains to large mulch basins. Much less water passes through bathroom sinks. If combined with the shower water it will fall under the shower system, if used alone, it can be drained to a single large plant, or have the flow split to irrigate two or three plants.

Constructed Wetlands

 

 

 

 

 

 

Wetland planter ecologically disposes greywater from an office with no sewer hookup.

If you produce more greywater than you need for irrigation, a constructed wetland can be incorporated into your system to “ecologically dispose” of some of the greywater. Wetlands absorb nutrients and filter particles from greywater, enabling it to be stored or sent through a properly designed drip irrigation system (a sand filter and pump will also be needed- this costs more money). Greywater is also a good source of irrigation for beautiful, water loving wetland plants. If you live near a natural waterway, a wetland can protect the creek from nutrient pollution that untreated greywater would provide. If you live in an arid climate, or are trying to reduce your fresh water use, we don’t recommend incorporating wetlands into greywater systems as they use up a lot of the water which could otherwise be used for irrigation.

Pumped Systems

If you can’t use gravity to transport the greywater (your yard is sloped uphill, or it’s flat and the plants are far away) you will need a “drum with effluent pump” system. The water flows into a large (usually 50 gallon) plastic drum that is either buried or located at ground level. In the drum a pump pushes the water out through irrigation lines (no emitters) to the landscape. Pumps add cost, use electricity, and will break, so avoid this if you can.

Indoor Greywater use

In most residential situations it is much simpler and more economical to utilize greywater outside, and not create a system that treats the water for indoor use. The exceptions are in houses that have high water use and minimal outdoor irrigation, and for larger buildings like apartments.

There are also very simple ways to reuse greywater inside that are not a “greywater system”. Buckets can catch greywater and clear water, the water wasted while warming up a shower. These buckets can be used to “bucket flush” a toilet, or carried outside. There are also simple designs like Sink Positive, and more complicated systems like the Brac system. Earthships have an interesting system that reuse greywater inside with greenhouse wetlands.

Plants and Greywater

 

 

 

 

 

 

Kiwi fruit irrigated with greywater

Low tech, simple greywater systems are best suited to specific, large plants. Use them to water trees, bushes, berry patches, shrubs, and large annuals. It’s much more difficult to water lots of small plants that are spread out over a large area (like a lawn or flower bed).

Greywater Policy

Greywater policies differ state to state. The best policy is from the state of Arizona. They have greywater guidelines to educate residents on how to build simple, safe, efficient, greywater irrigation systems. If people follow the guidelines their systems falls under a general permit and is automatically “legal”, that is, the residents don’t have to apply or pay for any permits or inspections.

California had the first greywater code in the nation, but it had been very restrictive and usually made it unfeasible for people to afford installing a permitted system. Because of this the vast majority of systems in California are unpermitted. Using data from a study done by the soap industry, Art Ludwig estimates that for every permit given in the past 20 years, there were 8,000 unpermitted systems built. In 2009 California changed its code, making it much easier for people to build simple, low cost systems legally.

Some states have no greywater policy and don’t give permits at all, while other states give experimental permits for systems on a case-by-case basis.

Images and information by Greywater Action used above are licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License., original found here: http://greywateraction.org/content/about-greywater-reuse

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

Measuring Free Chlorine – MyronLMeters.com

Posted by 25 Nov, 2012

TweetChlorine Residuals The presence of free chlorine in drinking water indicates that: 1) a sufficient amount of chlorine was added to the water to inactivate most of the bacteria and viruses that cause diarrheal disease; and, 2) the water is protected from recontamination during transport to the home, and during storage of water in the […]

Chlorine Residuals
The presence of free chlorine in drinking water indicates that: 1) a sufficient amount of chlorine was added to the water to inactivate most of the bacteria and viruses that cause diarrheal disease; and, 2) the water is protected from recontamination during transport to the home, and during storage of water in the household. Because the presence of free residual chlorine in drinking water indicates the likely absence of disease-causing organisms, it is used as one measure of the potability of drinking water.

Adding Chlorine
When chlorine is added to water as a disinfectant, a series of reactions occurs. These reactions are graphically depicted later in this article. The first of these reactions occurs when organic materials and metals present in the water react with the chlorine and transform it into compounds that are unavailable for disinfection. The amount of chlorine used in these reactions is termed the chlorine demand of the water. Any remaining chlorine concentration after the chlorine demand is met is termed total chlorine. Total chlorine is further subdivided into: 1) the amount of chlorine that then reacts with nitrates present in the water and is transformed into compounds that are much less effective disinfectants than free chlorine (termed combined chlorine); and, 2) the free chlorine, which is the chlorine available to inactivate disease-causing organisms, and is thus a measure used to determine the potability of water.

For example, when chlorine is added to completely pure water the chlorine demand will be zero, and there will be no nitrates present, so no combined chlorine will be formed. Thus, the free chlorine concentration will be equal to the concentration of chlorine added. When chlorine is added to natural waters, especially water from surface sources such as rivers, organic material will exert a chlorine demand, and combined chlorine will be formed by reaction with nitrates. Thus, the free chlorine concentration will be less than the concentration of chlorine initially
added.

Chlorine Addition Flow Chart

Testing Free Chlorine in Drinking Water

Testing free chlorine is recommended in the following circumstances:
• To conduct dosage testing in project areas
• To monitor and evaluate projects by testing stored drinking water in households

The goal of dosage testing is to determine how much sodium hypochlorite solution to add to water that will be used for drinking to maintain free chlorine residual in the water for the average time of storage of water in the household (typically 24 hours). This goal differs from the goal of infrastructure-based (piped) water treatment systems, whose aim is effective disinfection at the endpoints (i.e., water taps) of the system. The WHO recommends “a residual concentration of free chlorine of greater than or equal to 0.5 mg/litre after at least 30 minutes contact time at pH less than 8.0.” This definition is only appropriate for users who obtain water directly from a flowing tap. A free chlorine level of 0.5 mg/L can maintain the quality of water through a distribution network, but is not optimal to maintain the quality of the water when it is stored in the home in a bucket or jerry can for 24 hours.

Recommendations:
1. At 1 hour after the addition of sodium hypochlorite solution to water there should be no more than 2.0 mg/L of free chlorine residual present (this ensures the water does not have an unpleasant taste or odor).
2. At 24 hours after the addition of sodium hypochlorite to water in containers that are used by families for water storage there should be a minimum of 0.2 mg/L of free chlorine residual present (this ensures microbiologically clean water).
This methodology is approved by the World Health Organization (WHO), and is graphically depicted below. The maximum allowable WHO value for free chlorine residual in drinking water is 5 mg/L. The minimum recommended WHO value for free chlorine residual in treated drinking water is 0.2 mg/L. CDC recommends not exceeding 2.0 mg/L due to taste concerns, and chlorine residual decays over time in stored water.

sample chlorine decay curve

1. Free Chlorine as an Indicator of Sanitizing Strength

Chlorine, which kills bacteria by way of its power as an oxidizing agent, is the most popular germicide used in water treatment. Chlorine is not only used as a primary disinfectant, but also to establish a sufficient residual level of Free Available Chlorine (FAC) for ongoing disinfection.

FAC is the chlorine that remains after a certain amount is consumed by killing bacteria or reacting with other organic (ammonia, fecal matter) or inorganic (metals, dissolved CO2, Carbonates, etc) chemicals in solution. Measuring the amount of residual free chlorine in treated water is a well accepted method for determining its effectiveness in microbial control.

The Myron L Company FCE method for measuring residual disinfecting power is based on ORP, the specific chemical attribute of chlorine (and other oxidizing germicides) that kills bacteria and microbes.

2. FCE Free Chlorine Unit

The 6PIIFCE is the first handheld device to detect free chlorine directly, by measuring ORP. The ORP value is converted to a concentration reading (ppm) using a conversion table developed by Myron L Company through a series of experiments that precisely controlled chlorine levels and excluded interferants.

Other test methods typically rely on the user visually or digitally interpreting a color change resulting from an added reagent-dye. The reagent used radically alters the sample’s pH and converts the various chlorine species present into a single, easily measured species. This ignores the effect of changing pH on free chlorine effectiveness and disregards the fact that some chlorine species are better or worse sanitizers than others.

The Myron L Company 6PIIFCE avoids these pitfalls. The chemistry of the test sample is left unchanged from the source water. It accounts for the effect of pH on chlorine effectiveness by including pH in its calculation. For these reasons, the Ultrameter II’s FCE feature provides the best reading-to-reading picture of the rise and fall in sanitizing effectivity of free available chlorine.

The 6PIIFCE also avoids a common undesirable characteristic of other ORP-based methods by including a unique Predictive ORP value in its FCE calculation. This feature, based on a proprietary model for ORP sensor behavior, calculates a final stabilized ORP value in 1 to 2 minutes rather than the 10 to 15 minutes or more that is typically required for an ORP measurement.

Categories : Application Advice, Science and Industry Updates

Ultrapen PT2 Calibration – MyronLMeters.com

Posted by 28 Oct, 2012

Tweet Ultrapen PT2 Calibration We recommend calibrating twice a month, depending on usage. However, you should check the calibration whenever measurements are not as expected. 3-point Wet Calibration is most accurate and is recommended. NOTE: If the measurement is NOT within calibration limits for any reason, “Error” will display. Check to make sure you are […]


Ultrapen PT2 Calibration
We recommend calibrating twice a month, depending on usage. However, you should check the calibration whenever measurements are not as expected. 3-point Wet Calibration is most accurate and is recommended.

NOTE: If the measurement is NOT within calibration limits for any reason, “Error” will display. Check to make sure you are using a proper pH buffer solution. If the solution is correct, clean the glass bulb of the sensor with a cotton swab soaked in isopropyl alcohol. Restart calibration.

NOTE: Small bubbles trapped in the sensor may give a false calibration. After calibration is completed, measure the pH buffer solutions again to verify correct calibration.

NOTE: If at any point during calibration, you do not submerge the sensor in solution
before the flashing slows, allow the pen to power off and start over.

A. Calibration Preparation
1. For maximum accuracy, fill 2 clean containers with each pH buffer. Arrange them in such a way that you can clearly remember which is the rinse solution and which is the calibration buffer. If you don’t have enough buffer, you can use
1 container of each buffer for calibration and 1 container of clean water for all rinsing. Always rinse the pH sensor between buffer solutions.
2. Ensure the pH sensor is clean and free of debris.

B. 3-Point Calibration
Use pH 7, 4 and 10 buffers for 3-point calibration. You can find the buffer solutions here: http://www.myronlmeters.com/pH-Buffer-Calibration-Solutions-s/82.htm
1. Thoroughly rinse the pen by submerging the sensor in pH 7 buffer rinse solution and swirling it around.
2. Push and release the push button to turn the unit on.
3. Push and hold the push button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL” and “ESC”.
4. Release the button when “CAL” displays. The display will indicate “CAL” and
the LED will flash rapidly.
5. While the LED flashes rapidly, dip the pen in pH 7 buffer calibration solution
so that the sensor is completely submerged.
6. While the LED flashes slowly, the pH calibration point will display along with
“CAL”. Swirl the pen around to remove bubbles, keeping the sensor submerged.
7. If the pH 7 calibration is successful, the display will indicate “SAVEd”, then
“PUSHCONT” will be displayed.
8. Push and release the push button to continue. The LED will begin flashing rapidly.
9. Repeat steps 5 through 8 with pH 4 and 10 buffer calibration solutions.
10. After the 3rd calibration point is successfully saved, the display will indicate
“SAVEd” and power off.
11. Verify calibration by retesting the calibration solution.

C. 2-Point Calibration
Use pH 7 and 4 or 10 buffers for 2-point calibration.
1. Thoroughly rinse the pen by submerging the sensor in pH 7 buffer rinse solution and swirling it around.
2. Push and release the push button to turn the unit on.
3. Push and hold the push button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL” and “ESC”.
4. Release the button when “CAL” displays. The display will indicate “CAL” and
the LED will flash rapidly.
5. While the LED flashes rapidly, dip the pen in pH 7 buffer calibration solution
so that the sensor is completely submerged.
6. While the LED flashes slowly, the pH calibration point will display along with
“CAL”. Swirl the pen around to remove bubbles, keeping the sensor submerged.
7. If the pH 7 calibration is successful, the display will indicate “SAVEd”, then
“PUSHCONT” will be displayed.
8. Push and release the push button to continue. The LED will begin flashing rapidly.
9. Repeat steps 5 through 7 with pH 4 or 10 buffer calibration solution.
10. Leave the pen in the same buffer solution until the unit powers off. The offset will be applied to the remaining calibration point.
11. Verify calibration by retesting the calibration solution.

D. 1-Point Calibration
Use pH 7, 4 or 10 buffer for 1-point calibration.
1. Thoroughly rinse the pen by submerging the sensor in pH buffer rinse solution and swirling it around.
2. Push and release the push button to turn the unit on.
3. Push and hold the push button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL” and “ESC”.
4. Release the button when “CAL” displays. The display will indicate “CAL”
and the LED will flash rapidly.
5. While the LED flashes rapidly, dip the pen in pH buffer calibration solution
so that the sensor is completely submerged.
6. While the LED flashes slowly, the pH calibration point will display along with “CAL”;
swirl the pen around to remove bubbles, keeping the sensor submerged.
7. If the pH calibration is successful, the display will indicate “SAVEd”, then “PUSHCONT” will be displayed. “PUSHCONT” will not display if you calibrated 4 or 10.
8. Leave the pen in the same buffer solution until the unit powers off. The offset will be applied to the remaining calibration points.
9. Verify calibration by retesting the calibration solution.

E. Factory Calibration
When pH buffers are not available, the PT2 can be returned to factory default calibration using the FAC CAL function. This will erase any stored wet calibration. NOTE: default factory calibration resets the electronics only and does NOT take the condition of the sensor into consideration.
To return your unit to factory calibration:
1. Push and release the push button.
2. Push and hold the push button. The display will alternate between “CAL”, “FAC CAL”, “ºCºF TEMP”, “ModE SEL” and “ESC”.
3. Release the button when “FAC CAL” displays. The display will alternate between “PUSHnHLD” and “FAC CAL”.
4. Push and hold the push button. “SAVEd FAC” displays indicating the pen has been reset to its factory calibration.

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Categories : Product Updates, Technical Tips

A Book On Desalination Plant Concentrate Management by Nikolay Voutchkov

Posted by 18 Oct, 2012

Tweet           A Book On Desalination Plant Concentrate Management by Nikolay Voutchkov, PE, BCEE of Water Globe Consulting and one of Myron L Meters valued customers This book provides an overview of the alternatives for management of concentrate generated by brackish water and seawater desalination plants, as well as site specific […]

 

 

 

 

 

A Book On Desalination Plant Concentrate Management by Nikolay Voutchkov, PE, BCEE of Water Globe Consulting and one of Myron L Meters valued customers

This book provides an overview of the alternatives for management of concentrate generated by brackish water and seawater desalination plants, as well as site specific factors involved in the selection of the most viable alternative for a given project, and the environmental permitting requirements and studies associated with their implementation. The book focuses on widely used alternatives for disposal of concentrate, including discharge to surface water bodies; disposal to the wastewater collection system; deep well injection; land application; evaporation; and zero liquid discharge. Direct discharge through new outfall; discharge through existing wastewater treatment plant outfall; and co-disposal with the cooling water of existing coastal power plant are thoroughly described and design guidance for the use of these concentrate disposal alternatives is presented with engineers and practitioners in the field of desalination in mind. Key advantages, disadvantages, environmental impact issues and possible solutions are presented for each discharge alternative. Easy-to-use graphs depicting construction costs as a function of concentrate flowrate are provided for all key concentrate management alternatives.

Mr. Voutchkov is a registered professional engineer and a board certified environmental engineer (BCEE) by the American Academy of Environmental Engineers. He has over 25 years of experience in planning, environmental review, permitting and implementation of large seawater desalination, water treatment and water reclamation projects in the US and abroad. Mr. Voutchkov has extensive expertise with all phases of seawater desalination project delivery: from conceptual scoping, pilot testing and feasibility analysis; to front-end and detailed project design; environmental review and permitting; contractor procurement; project construction and operations oversight/asset management. Mr. Voutchkov is President of Water Globe Consulting a private company specialized in providing expert advisory services in the field of seawater desalination and reuse. For over 11 years prior to establishing his project advisory firm, Mr. Voutchkov was a Chief Technology Officer and Corporate Technical Director for Poseidon Resources, a private company involved in the development of the largest seawater desalination projects in the USA. In recognition of his outstanding efforts and contribution to the field of seawater desalination, Mr. Voutchkov has received a number of prestigious awards from the International Desalination Association, the International Water Association and the American Academy of Environmental Engineers. He is one of the principal authors of the American Water Works Association s Manual of Water Supply Practices on Reverse Osmosis and Nanofiltration and of the World Health Organization s Guidance for the Health and Environmental Aspects Applicable to Desalination. Mr. Voutchkov has published over 40 technical articles in the field of water and wastewater treatment and reuse, and is co-author of several books and manuals of practice on membrane treatment and desalination. He wrote a book on “Seawater Pretreatment”, which was published by Water Treatment Academy in 2010.

Desalination Plant Concentrate Management

By Nikolay Voutchkov, PE, BCEE

ISBN: 978-974-496-357-4, 181 pages, Hardcover, Published by Technobiz Communications

CONTENTS

PREFACE

Ch. 1. Introduction to Concentrate Management

Ch. 2. Desalination Plant Discharge Characterization

2.1. Desalination Plant Waste Streams

2.2. Concentrate

2.3. Spent Pretreatment Backwash Water

2.4. Chemical Cleaning Residuals

Ch. 3. Surface Water Discharge of Concentrate

3.1. New Surface Water Discharge

3.2. Potential Environmental Impacts

3.3. Concentrate Treatment Prior to Surface Water Discharge

3.4. Design Guidelines for Surface Water Discharges

3.5. Costs for New Surface Water Discharge

3.6. Case Studies of New Surface Water Discharges

3.7. Co-Disposal with Wastewater Effluent

3.8. Co-Disposal with Power Plant Cooling Water

Ch. 4. Discharge to Sanitary Sewer

4.1. Description

4.2. Potential Environmental Impacts

4.3. Effect on Sanitary Sewer Operations

4.4. Effect on Wastewater Treatment Operations

4.5. Effect on Water Reuse

4.6. Design and Configuration Guidelines

4.7. Costs for Sanitary Sewer Discharge

Ch. 5. Deep Well Injection

5.1. Description

5.2. Potential Environmental Impacts

5.3. Criteria and Methods for Feasibility Assessment

5.4. Design and Configuration Guidelines

5.5. Injection Well Costs

Ch. 6. Land Application

6.1. Description

6.2. Potential Environmental Impacts

6.3. Criteria and Methods for Feasibility Assessment

6.4. Design and Configuration Guidelines

6.5. Land Application Costs

Ch. 7. Evaporation Ponds

7.1. Description

7.2. Potential Environmental Impacts

7.3. Criteria and Methods for Feasibility Assessment

7.4. Design and Configuration Guidelines

7.5. Evaporation Pond Costs

Ch. 8. Zero Liquid Discharge Concentrate Disposal Systems

8.1. Description

8.2. Potential Environmental Impacts

8.3. Criteria and Methods for Feasibility Assessment

8.4. Design and Configuration Guidelines

8.5. Zero Liquid Discharge Costs

Ch. 9. Beneficial Use of Concentrate

9.1. Technology Overview

9.2. Feasibility of Beneficial Concentrate Use

Ch. 10. Regional Concentrate Management

10.1. Types of Regional Concentrate Management Systems

10.2. Use of Brackish Water Concentrate in SWRO Plants

Ch. 11. Non-Concentrate Residuals Management

11.1. Spent Pretreatment Backwash Water

11.2. Chemical Cleaning Residuals

Ch. 12. Comparison of Concentrate Management Alternatives

12.1. Selection of Concentrate Management Approach

12.2. Costs

12.3. Environmental Impacts

12.4. Regulatory Acceptance

12.5. Ease of Implementation

12.6. Site Footprint

12.7. Reliability and Operational Constraints

12.8. Energy Use

You can order your book here: http://talloaks.com/Zencart/index.php?main_page=product_info&cPath=1_9&products_id=85

Categories : MyronLMeters.com Valued Customers, Science and Industry Updates, Technical Tips

Buying and Using a pH Meter for Food Processing – MyronLMeters.com

Posted by 2 Oct, 2012

TweetWhat is pH and why do I need to measure it? pH measures the amount of acidity or alkalinity in a food or solution using a numerical scale between  1 and 14. A pH value of 1 is most acidic, a pH value of 7 is neutral, and values above 7 are referred to as […]

What is pH and why do I need to measure it?

pH measures the amount of acidity or alkalinity in a food or solution using a numerical scale between  1 and 14. A pH value of 1 is most acidic, a pH value of 7 is neutral, and values above 7 are referred to as basic or alkaline. Acidified foods have a pH value less than or equal to 4.6. The proper pH of a canned food product can be critical to ensuring the safety of the product. It is very important that pH testing be done correctly and accurately.

How is pH measured?

If you process acidified foods, you will be required to monitor the pH of the product that you produce. Depending on the pH of the product, you may be able to use paper pH strips (often referred to as litmus paper), or required to use a pH meter. Paper strips that measure pH rely on a color change in the paper to indicate product pH. Paper strips can be used to measure pH if the product pH is less than 4.0. Paper strips are an inexpensive way to test pH, but can be inaccurate or difficult to read. A pH meter measures the amount of hydrogen-ion (acid) in solution using a glass electrode immersed in the solution. A pH meter must be used when product pH is greater than, or equal to, 4.0. If you are canning acidified foods, accurately monitoring and recording the product pH is key to knowing that you are selling a safe product.

What is equilibrium pH?

Equilibrium pH is the pH of a food product after the added acid has reached throughout the food; the pH of the acid brine and the food that have equilibrated.  When you monitor pH as part of process monitoring, it is the equilibrium pH that you are measuring. For a proper pH reading, you should test the pH of the product roughly 24 hours after processing, once the jars have cooled to room temperature and stabilized. Do not take the pH of a product just before or right after canning because it will not be an accurate measure of the equilibrium pH.

What should I look for if I need to purchase a pH meter?

If you are required to check your product pH with a meter, there are several things to consider.

Accuracy. Accuracy is listed as a range of +0.XX pH units. This means that the meter may read so many pH units above or below the actual pH of the product. Purchase a pH meter with an accuracy of +0.02 units or better. For instance, a pH meter with an accuracy of

+0.01 is a good choice. A pH meter with an accuracy of +0.10 is not a good choice, it is not accurate enough for all products.

Calibration.

All pH meters must be calibrated (checked against a known standard) to assure accuracy. Standards are colored liquids of known pH. Buy a meter that uses at least a 2-point calibration; for acidified foods you will calibrate your meter with pH 4.0 and 7.0 buffers.

Electrode. The electrode is the part of the instrument that is immersed in solution. When considering which pH meter to purchase, consider the cost of replacement electrodes. Some  electrodes  have  special  non-clog  tips  and  these  may  be  useful  is  you  will  be measuring the pH of foods that are not easily blended.

Temperature. pH readings are affected by temperature. In order to get an accurate reading, the pH meter must be calibrated at the same temperature as the samples being tested. More expensive meters will compensate for variations in sample temperature (too warm or too cold). Myron L meters have automatic temperature compensation. If you can afford a meter with this feature, it’s nice to have.

What should I buy?

The cost of a pH meter ranges from under $100 to well over $500.  As a starting point, there are several styles that small food and beverage processors currently use.

Testing the Equilibrium pH of an Acidified Food Product

1.   Open one jar and take a representative sample of your food product once it has cooled, usually 12 to 24 hours after processing. You should sample each batch. Heating will drive the acid into your food product; sampling after processing (and cooling) will give you an accurate reading of the equilibrium pH.

2.   Strain the solids, draining out the liquid (brine) from the jar. Place the strained solids into a blender.

3.   Blend the product, adding distilled water if necessary, to produce a slurry. Added distilled water will not change the pH of the product and will allow for effective blending. You can purchase distilled water at many grocery stores or drug stores.

4.   Use a calibrated pH meter to measure pH.

The pH meter must be calibrated using at least 2-point calibration with pH 4.0 and 7.0 buffers. Myron L Meters recommends a three point calibration.

The pH meter must be calibrated each day that you use it. A pH meter must be used to monitor the pH of foods with an equilibrium pH greater than 4.0.

5.   Record the results in your batch log.

*Myron L meters are used by Tyson, Sara Lee, Gordon Food Service, Better Baked Foods, Schreiber Foods, Homestead Slow Foods, and others in the food

processing industry.

These are our two most popular handheld pH meters:

Ultrapen PT2

 

 

 

 

 

 

https://www.myronlmeters.com/Ultrapen-PT2-Multiparameter-Meter-p/dh-up-pt2-ss.htm

ULTRAPEN PT2 pH and Temperature Pen

Accuracy of +/- 0.01 pH

Reliable Repeatable Results

Easy Calibration

Automatic Temperature Compensation

Measures Temperature

Durable, Fully Potted Circuitry

Waterproof

Comes with 2oz bottle of pH Storage Solution

 

 

 

 

 

 

 

Ultrameter II – 6PII

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

Multi-Parameter: Conductivity, TDS, Resistivity, pH, ORP, Temperature, Free Chlorine (FCE)

+/-1% Accuracy of Reading

Memory Storage: Save up to 100 samples w/ Date & Time stamp

Wireless Download Module Optional

Waterproof

 

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

Reverse Osmosis and RO Meters – MyronLMeters.com

Posted by 1 Oct, 2012

TweetReverse Osmosis and RO Meters – MyronLMeters.com               Schematics of a reverse osmosis system (desalination) using a pressure exchanger. 1: Sea water inflow, 2: Fresh water flow (40%), 3: Concentrate flow (60%), 4: Sea water flow (60%), 5: Concentrate (drain), A: Pump flow (40%), B: Circulation pump, C: Osmosis unit […]

Reverse Osmosis and RO Meters – MyronLMeters.com

 

 

 

 

 

 

 

Schematics of a reverse osmosis system (desalination) using a pressure exchanger.
1: Sea water inflow,
2: Fresh water flow (40%),
3: Concentrate flow (60%),
4: Sea water flow (60%),
5: Concentrate (drain),
A: Pump flow (40%),
B: Circulation pump,
C: Osmosis unit with membrane,
D: Pressure exchanger

Reverse osmosis (RO) is a membrane-technology filtration method that removes many types of large molecules and ions from solutions by applying pressure to the solution when it is on one side of a selective membrane. The result is that the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side. To be “selective,” this membrane should not allow large molecules or ions through the pores (holes), but should allow smaller components of the solution (such as the solvent) to pass freely.

In normal osmosis, the solvent naturally moves from an area of low solute concentration (High Water Potential), through a membrane to an area of high solute concentration (Low Water Potential). The movement of a pure solvent to equalize solute concentrations on each side of a membrane generates osmotic pressure. Applying an external pressure to reverse the natural flow of pure solvent, thus, is reverse osmosis. The process is similar to other membrane technology applications. However, there are key differences between reverse osmosis and filtration. The predominant removal mechanism in membrane filtration is straining, or size exclusion, so the process can theoretically achieve perfect exclusion of particles regardless of operational parameters such as influent pressure and concentration. Reverse osmosis, however, involves a diffusive mechanism so that separation efficiency is dependent on solute concentration, pressure, and water flux rate. Reverse osmosis is most commonly known for its use in drinking water purification from seawater, removing the salt and other substances from the water molecules.

Reverse osmosis is the process of forcing a solvent from a region of high solute concentration through a semipermeable membrane to a region of low solute concentration by applying a pressure in excess of the osmotic pressure. The largest and most important application of reverse osmosis is to the separation of pure water from seawater and brackish waters; seawater or brackish water is pressurized against one surface of the membrane, causing transport of salt-depleted water across the membrane and emergence of potable drinking water from the low-pressure side.

The membranes used for reverse osmosis have a dense layer in the polymer matrix — either the skin of an asymmetric membrane or an interfacially polymerized layer within a thin-film-composite membrane — where the separation occurs. In most cases, the membrane is designed to allow only water to pass through this dense layer, while preventing the passage of solutes (such as salt ions). This process requires that a high pressure be exerted on the high concentration side of the membrane, usually 2–17 bar (30–250 psi) for fresh and brackish water, and 40–82 bar (600–1200 psi) for seawater, which has around 27 bar (390 psi)[3] natural osmotic pressure that must be overcome. This process is best known for its use in desalination (removing the salt and other minerals from sea water to get fresh water), but since the early 1970s it has also been used to purify fresh water for medical, industrial, and domestic applications.

Osmosis describes how solvent moves between two solutions separated by a permeable membrane to reduce concentration differences between the solutions. When two solutions with different concentrations of a solute are mixed, the total amount of solutes in the two solutions will be equally distributed in the total amount of solvent from the two solutions. Instead of mixing the two solutions together, they can be put in two compartments where they are separated from each other by a semipermeable membrane. The semipermeable membrane does not allow the solutes to move from one compartment to the other, but allows the solvent to move. Since equilibrium cannot be achieved by the movement of solutes from the compartment with high solute concentration to the one with low solute concentration, it is instead achieved by the movement of the solvent from areas of low solute concentration to areas of high solute concentration. When the solvent moves away from low concentration areas, it causes these areas to become more concentrated. On the other side, when the solvent moves into areas of high concentration, solute concentration will decrease. This process is termed osmosis. The tendency for solvent to flow through the membrane can be expressed as “osmotic pressure”, since it is analogous to flow caused by a pressure differential. Osmosis is an example of diffusion.

In reverse osmosis, in a similar setup as that in osmosis, pressure is applied to the compartment with high concentration. In this case, there are two forces influencing the movement of water: the pressure caused by the difference in solute concentration between the two compartments (the osmotic pressure) and the externally applied pressure.

Around the world, household drinking water purification systems, including a reverse osmosis step, are commonly used for improving water for drinking and cooking.

Such systems typically include a number of steps:

a sediment filter to trap particles, including rust and calcium carbonate

optionally, a second sediment filter with smaller pores

an activated carbon filter to trap organic chemicals and chlorine, which will attack and degrade TFC reverse osmosis membranes

a reverse osmosis (RO) filter, which is a thin film composite membrane (TFM or TFC)

optionally, a second carbon filter to capture those chemicals not removed by the RO membrane

optionally an ultra-violet lamp for sterilizing any microbes that may escape filtering by the reverse osmosis membrane

In some systems, the carbon prefilter is omitted, and cellulose triacetate membrane (CTA) is used. The CTA membrane is prone to rotting unless protected by chlorinated water, while the TFC membrane is prone to breaking down under the influence of chlorine. In CTA systems, a carbon postfilter is needed to remove chlorine from the final product, water.

Portable reverse osmosis (RO) water processors are sold for personal water purification. To work effectively, the water feeding to these units should be under some pressure (40 psi or greater is the norm). Portable RO water processors can be used by people who live in rural areas without clean water, far away from the city’s water pipes. Rural people filter river or ocean water themselves, as the device is easy to use (saline water may need special membranes). Some travelers on long boating, fishing, or island camping trips, or in countries where the local water supply is polluted or substandard, use RO water processors coupled with one or more UV sterilizers. RO systems are also now extensively used by marine aquarium enthusiasts. In the production of bottled mineral water, the water passes through an RO water processor to remove pollutants and microorganisms. In European countries, though, such processing of Natural Mineral Water (as defined by a European Directive) is not allowed under European law. In practice, a fraction of the living bacteria can and do pass through RO membranes through minor imperfections, or bypass the membrane entirely through tiny leaks in surrounding seals. Thus, complete RO systems may include additional water treatment stages that use ultraviolet light or ozone to prevent microbiological contamination.

Membrane pore sizes can vary from 0.1 nanometres (3.9×10−9 in) to 5,000 nanometres (0.00020 in) depending on filter type. “Particle filtration” removes particles of 1 micrometre (3.9×10−5 in) or larger. Microfiltration removes particles of 50 nm or larger. “Ultrafiltration” removes particles of roughly 3 nm or larger. “Nanofiltration” removes particles of 1 nm or larger. Reverse osmosis is in the final category of membrane filtration, “hyperfiltration”, and removes particles larger than 0.1 nm.

Water and waste water purification

Rain water collected from storm drains is purified with reverse osmosis water processors and used for landscape irrigation and industrial cooling in Los Angeles and other cities, as a solution to the problem of water shortages.

In industry, reverse osmosis removes minerals from boiler water at power plants. The water is boiled and condensed repeatedly. It must be as pure as possible so that it does not leave deposits on the machinery or cause corrosion. The deposits inside or outside the boiler tubes may result in under-performance of the boiler, bringing down its efficiency and resulting in poor steam production, hence poor power production at turbine.

It is also used to clean effluent and brackish groundwater. The effluent in larger volumes (more than 500 cu. meter per day) should be treated in an effluent treatment plant first, and then the clear effluent is subjected to reverse osmosis system. Treatment cost is reduced significantly and membrane life of the RO system is increased.

The process of reverse osmosis can be used for the production of deionized water.

RO process for water purification does not require thermal energy. Flow through RO system can be regulated by high pressure pump. The recovery of purified water depends upon various factors including membrane sizes, membrane pore size, temperature, operating pressure and membrane surface area.

In 2002, Singapore announced that a process named NEWater would be a significant part of its future water plans. It involves using reverse osmosis to treat domestic wastewater before discharging the NEWater back into the reservoirs.

Food industry

In addition to desalination, reverse osmosis is a more economical operation for concentrating food liquids (such as fruit juices) than conventional heat-treatment processes. Research has been done on concentration of orange juice and tomato juice. Its advantages include a lower operating cost and the ability to avoid heat-treatment processes, which makes it suitable for heat-sensitive substances like the protein and enzymes found in most food products.

Reverse osmosis is extensively used in the dairy industry for the production of whey protein powders and for the concentration of milk to reduce shipping costs. In whey applications, the whey (liquid remaining after cheese manufacture) is concentrated with RO from 6% total solids to 10–20% total solids before UF (ultrafiltration) processing. The UF retentate can then be used to make various whey powders, including whey protein isolate used in bodybuilding formulations. Additionally, the UF permeate, which contains lactose, is concentrated by RO from 5% total solids to 18–22% total solids to reduce crystallization and drying costs of the lactose powder.

Although use of the process was once avoided in the wine industry, it is now widely understood and used. An estimated 60 reverse osmosis machines were in use in Bordeaux, France in 2002. Known users include many of the elite classed growths.

Car washing

Because of its lower mineral content, reverse osmosis water is often used in car washes during the final vehicle rinse to prevent water spotting on the vehicle. Reverse osmosis is often used to conserve and recycle water within the wash/pre-rinse cycles, especially in drought stricken areas where water conservation is important. Reverse osmosis water also enables the car wash operator to reduce the demands on the vehicle drying equipment, such as air blowers.

Maple syrup production

In 1946, some maple syrup producers started using reverse osmosis to remove water from sap before the sap is boiled down to syrup. The use of reverse osmosis allows approximately 75-90% of the water to be removed from the sap, reducing energy consumption and exposure of the syrup to high temperatures. Microbial contamination and degradation of the membranes has to be monitored.

Hydrogen production

For small-scale production of hydrogen, reverse osmosis is sometimes used to prevent formation of minerals on the surface of electrodes.

Reef aquariums

Many reef aquarium keepers use reverse osmosis systems for their artificial mixture of seawater. Ordinary tap water can often contain excessive chlorine, chloramines, copper, nitrogen, phosphates, silicates, or many other chemicals detrimental to the sensitive organisms in a reef environment. Contaminants such as nitrogen compounds and phosphates can lead to excessive, and unwanted, algae growth. An effective combination of both reverse osmosis and deionization (RO/DI) is the most popular among reef aquarium keepers, and is preferred above other water purification processes due to the low cost of ownership and minimal operating costs. Where chlorine and chloramines are found in the water, carbon filtration is needed before the membrane, as the common residential membrane used by reef keepers does not cope with these compounds.

Desalination

Areas that have either no or limited surface water or groundwater may choose to desalinate seawater or brackish water to obtain drinking water. Reverse osmosis is a common method of desalination, although 85 percent of desalinated water is produced in multistage flash plants.[5]

Large reverse osmosis and multistage flash desalination plants are used in the Middle East, especially Saudi Arabia. The energy requirements of the plants are large, but electricity can be produced relatively cheaply with the abundant oil reserves in the region. The desalination plants are often located adjacent to the power plants, which reduces energy losses in transmission and allows waste heat to be used in the desalination process of multistage flash plants, reducing the amount of energy needed to desalinate the water and providing cooling for the power plant.

Sea water reverse osmosis (SWRO) is a reverse osmosis desalination membrane process that has been commercially used since the early 1970s. Its first practical use was demonstrated by Sidney Loeb and Srinivasa Sourirajan from UCLA in Coalinga, California. Because no heating or phase changes are needed, energy requirements are low in comparison to other processes of desalination, but are still much higher than those required for other forms of water supply (including reverse osmosis treatment of wastewater).

The Ashkelon seawater reverse osmosis (SWRO) desalination plant in Israel is the largest in the world. The project was developed as a BOT (Build-Operate-Transfer) by a consortium of three international companies: Veolia water, IDE Technologies and Elran.

The typical single-pass SWRO system consists of the following components:

Intake

Pretreatment

High pressure pump

Membrane assembly

Remineralization and pH adjustment

Disinfection

Alarm/control panel

Pretreatment

Pretreatment is important when working with RO and nanofiltration (NF) membranes due to the nature of their spiral wound design. The material is engineered in such a fashion as to allow only one-way flow through the system. As such, the spiral wound design does not allow for backpulsing with water or air agitation to scour its surface and remove solids. Since accumulated material cannot be removed from the membrane surface systems, they are highly susceptible to fouling (loss of production capacity). Therefore, pretreatment is a necessity for any RO or NF system. Pretreatment in SWRO systems has four major components:

Screening of solids: Solids within the water must be removed and the water treated to prevent fouling of the membranes by fine particle or biological growth, and reduce the risk of damage to high-pressure pump components.

Cartridge filtration: Generally, string-wound polypropylene filters are used to remove particles of 1–5 µm diameter.

Dosing: Oxidizing biocides, such as chlorine, are added to kill bacteria, followed by bisulfite dosing to deactivate the chlorine, which can destroy a thin-film composite membrane. There are also biofouling inhibitors, which do not kill bacteria, but simply prevent them from growing slime on the membrane surface and plant walls.

Prefiltration pH adjustment: If the pH, hardness and the alkalinity in the feedwater result in a scaling tendency when they are concentrated in the reject stream, acid is dosed to maintain carbonates in their soluble carbonic acid form.

CO32– + H3O+ = HCO3– + H2O

HCO3– + H3O+ = H2CO3 + H2O

Carbonic acid cannot combine with calcium to form calcium carbonate scale. Calcium carbonate scaling tendency is estimated using the Langelier saturation index (LSI). Adding too much sulfuric acid to control carbonate scales may result in calcium sulfate, barium sulfate or strontium sulfate scale formation on the RO membrane.

Antiscalants: Scale inhibitors (also known as antiscalants) prevent formation of all scales compared to acid, which can only prevent formation of calcium carbonate and calcium phosphate scales. In addition to inhibiting carbonate and phosphate scales, antiscalants inhibit sulfate and fluoride scales, disperse colloids and metal oxides. Despite claims that antiscalants can inhibit silica formation, there is no concrete evidence to prove that silica polymerization can be inhibited by antiscalants. Antiscalants can control acid soluble scales at a fraction of the dosage required to control the same scale using sulfuric acid.

Some small scale desalination units use Beach wells, they are usually drilled on the seashore in close vicinity to the ocean. These intake facilities are relatively simple to build and the seawater they collect is pretreated via slow filtration through the subsurface sand/seabed formations in the area of source water extraction. Raw seawater collected using beach wells is often of better quality in terms of solids, silt, oil and grease, natural organic contamination and aquatic microorganisms, compared to open seawater intakes. Sometimes, beach intakes may also yield source water of lower salinity.

High pressure pump

The pump supplies the pressure needed to push water through the membrane, even as the membrane rejects the passage of salt through it. Typical pressures for brackish water range from 225 to 375 psi (15.5 to 26 bar, or 1.6 to 2.6 MPa). In the case of seawater, they range from 800 to 1,180 psi (55 to 81.5 bar or 6 to 8 MPa). This requires a large amount of energy.

Membrane assembly

The layers of a membrane

The membrane assembly consists of a pressure vessel with a membrane that allows feed water to be pressed against it. The membrane must be strong enough to withstand whatever pressure is applied against it. RO membranes are made in a variety of configurations, with the two most common configurations being spiral-wound and hollow-fiber.

Remineralization and pH adjustment

The desalinated water is very corrosive and is “stabilized” to protect downstream pipelines and storages, usually by adding lime or caustic to prevent corrosion of concrete lined surfaces. Liming material is used to adjust pH between 6.8 and 8.1 to meet the potable water specifications, primarily for effective disinfection and for corrosion control.

Disinfection

Post-treatment consists of preparing the water for distribution after filtration. Reverse osmosis is an effective barrier to pathogens, however post-treatment provides secondary protection against compromised membranes and downstream problems. Disinfection by means of UV lamps (sometimes called germicidal or bactericidal) may be used to sterilize pathogens which bypassed the reverse osmosis process. Chlorination or chloramination (chlorine and ammonia) protects against pathogens which may have lodged in the distribution system downstream, such as from new construction, backwash, compromised pipes, etc.[citation needed]

Disadvantages

Household reverse osmosis units use a lot of water because they have low back pressure. As a result, they recover only 5 to 15 percent of the water entering the system. The remainder is discharged as waste water. Because waste water carries with it the rejected contaminants, methods to recover this water are not practical for household systems. Waste water is typically connected to the house drains and will add to the load on household septic systems. An RO unit delivering 5 gallons of treated water a day may discharge anywhere between 20 and 90 gallons of waste water a day. For household use, however, and based on consumption of half a gallon per day, this may amount to less than a toilet-flush per day.

Large-scale industrial/municipal systems have a production efficiency of 75% – 80%, or as high as 90%, because they can generate the high pressure needed for more efficient RO filtration. On the other hand, as efficiency of waste water rates increases in commercial operations effective removal rates tend to become reduced, as evidenced by TDS counts.

Reverse Osmosis Removes Minerals

Reverse Osmosis (RO) removesd more than 90-99.99% of all the contaminants including minerals from the drinking water supply. 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) stated that most of healthy minerals needed by the human body come from food or dietary supplementary sources and not from drinking tap water. In addition, some minerals found in water can be harmful to human health.  The evidence is strong that calcium and magnesium are essential elements for human body.  However, this is not to suggest that we should make up this deficiency through water consumption. Tap water presents a variety of inorganic minerals which human body has difficulty absorbing. 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).

A number of studies have looked at the long term health effects of drinking demineralized water. However, demineralized water can be remineralized, and this process has been done in instances when processing demineralized water for consumption. Dasani water uses this process.

Water filtered or treated by RO is generally pure, clean, and healthy.  RO treatment is currently the only technology that can remove emerging contaminants (prescription drugs and perchlorate) and some others (i.e., arsenic, cyanide, and fluoride) that are difficult to remove by other methods. Consumers should not be concerned about the removal of minerals by RO system.  WHO (2009) and WQA (2011) pointed out, that the human body obtains most minerals from food or supplements, not from drinking water.

Popular RO Meters

RO Meter – RO-1: 0-1250 ppm with color band

 

 

 

 

 

 

 

 

 

Instant and accurate TDS tests
Electronic Internal Standard for easy field calibration
Fast Auto Temperature Compensation
Rugged design for years of trouble-free testing
Simple to use

 

758II: Conductivity Digital Monitor/Controller

Conductivity monitor/controller

 

 

 

 

 

 

 

 

 

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.

The unique circuitry of the 750 Series II Conductivity Monitor/controllers guarantees accurate and reliable measurements. Drift-free performance is assured by “field proven” electronics, including automatic DC offset compensation and highly accurate drive voltage.

Since temperature compensation is at the heart of accurate water measurement, all Myron L Monitor/controllers feature a highly refined and precise TC circuit. This feature perfectly matches the water temperature coefficient as it changes. All models corrected to 25′C. The TC may be disabled to conform with USP requirements.

Built-in electronic calibration allows for fast quality checks without standard solutions. (Note: for maximum system accuracy standard solutions are recommended).

Aquaswitch I 

Aquaswitch

 

 

 

 

 

 

 

 

 

For use with any two-bank supply systems (DI banks, RO systems, etc)

Must use with Inline Monitor/Controller

The AQUASWITCH I is a special purpose dedicated instrument which automatically “switches” from an exhausted DI or RO bank to a fresh stand-by bank. LEDs continually give the condition of both banks. An alarm output is activated as each bank is depleted.

Ultrameter III – 9PTK

Measures 9 Parameters: Conductivity, Resistivity, 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 : Product Updates, Science and Industry Updates, Technical Tips

Conductivity and Conductivity Meters – MyronLMeters.com

Posted by 23 Sep, 2012

TweetThe conductivity (or specific conductance) of a solution is a measure of its ability to conduct electricity. The standard unit of conductivity is siemens per meter (S/m). Conductivity measurements are used routinely in many industrial and environmental applications as a fast, inexpensive and reliable way of measuring ionic content in a solution. For example, the […]

The conductivity (or specific conductance) of a solution is a measure of its ability to conduct electricity. The standard unit of conductivity is siemens per meter (S/m).

Conductivity measurements are used routinely in many industrial and environmental applications as a fast, inexpensive and reliable way of measuring ionic content in a solution. For example, the measurement of product conductivity is a typical way to monitor and continuously trend the performance of water purification systems.

In many cases, conductivity is linked directly to the total dissolved solids (TDS). High quality deionized water has a conductivity of about 5.5 μS/m, typical drinking water in the range of 5-50 mS/m, while sea water about 5 S/m (i.e., sea water’s conductivity is one million times higher than deionized water).

Conductivity is traditionally determined by measuring the AC resistance of the solution between two electrodes.

Resistivity of pure water (in MΩ-cm) as a function of temperature

The standard unit of conductivity is S/m and usually refers to 25 °C (standard temperature). Often encountered in industry is the traditional unit of μS/cm. 106 μS/cm = 103 mS/cm = 1 S/cm. The numbers in μS/cm are higher than those in μS/m by a factor of 100 (i.e., 1 μS/cm = 100 μS/m). Occasionally a unit of “EC” (electrical conductivity) is found on scales of instruments: 1 EC = 1 μS/cm. Sometimes encountered is a so-called mho (reciprocal of ohm): 1 mho/m = 1 S/m. Historically, mhos antedate Siemens by many decades; good vacuum-tube testers, for instance, gave transconductance readings in micromhos.

The commonly used standard cell has a width of 1 cm, and thus for very pure water in equilibrium with air would have a resistance of about 106 ohm, known as a megohm. Ultra-pure water could achieve 18 megohms or more. Thus in the past megohm-cm was used, sometimes abbreviated to “megohm”. Sometimes conductivity is given just in “microSiemens” (omitting the distance term in the unit). While this is an error, it’s usually assumed to be equal to the traditional μS/cm. The typical conversion of conductivity to the total dissolved solids is done assuming that the solid is sodium chloride: 1 μS/cm is then an equivalent of about 0.6 mg of NaCl per kg of water.

A conductivity meter and probe

The electrical conductivity of a solution is measured by determining the resistance of the solution between two flat or cylindrical electrodes separated by a fixed distance. An alternating voltage is used in order to avoid electrolysis. The resistance is measured by a conductivity meter. Typical frequencies used are in the range 1–3 kHz. The dependence on the frequency is usually small, but may become appreciable at very high frequencies, an effect known as the Debye–Falkenhagen effect.

A wide variety of instrumentation is commercially available. There are two types of cell, the classical type with flat or cylindrical electrodes and a second type based on induction. Many commercial systems, Myron L meters, e.g.,  offer automatic temperature correction.

MyronLMeters.com offers many reliable conductivity meters – some analog, some digital, some pen-style, some multiparameter – but all accurate, reliable, and easy-to-use.

Myron L analog handheld conductivity meter 512M5

 

 

 

 

 

 

 

 

 

Analog Handheld conductivity meter

512M5: 0-5000 micromhos/microsiemens

Instant and accurate Conductivity tests

Electronic Internal Standard for easy field calibration

Fast Auto Temperature Compensation

Rugged design for years of trouble-free testing

Simple to use

 

Myron L Digital Handheld Conductivity, TDS, Salinity Pen

 

 

 

 

 

 

 

 

 

Digital Handheld Conductivity, TDS, Salinity Pen

ULTRAPEN PT1 Conductivity – TDS – Salinity Pen

Accuracy of +/-1% of READING (+/-.2% at Calibration Point)

Reliable Repeatable Results

Solution modes: KCl, NaCl and 442

Automatic Temperature Compensation

Autoranging

Durable, Fully Potted Circuitry

Waterproof

 

Myron L Digital Handheld Multiparameter Meter: Ultrameter 6P II FCe

 

 

 

 

 

 

 

 

 

Digital Handheld Multi-Parameter meter: Conductivity, TDS, Resistivity, pH, ORP, Temperature, Free Chlorine (FCE)
+/-1% Accuracy of Reading
Memory Storage: Save up to 100 samples w/ Date & Time stamp
Wireless Download Module Optional
Waterproof

 

Myron L digital inline conductivity monitor/controller 758II

 

 

 

 

 

 

 

 

 

Digital In-Line Conductivity Monitor/Controller

The unique circuitry of our 750 Series II Conductivity Inline Meters guarantees accurate and reliable measurements. Drift-free performance is assured by “field proven” electronics, including automatic DC offset compensation and highly accurate drive voltage.

Since Temperature Compensation is at the heart of accurate water measurement, all Myron L Monitor/controllers feature a highly refined and precise TC circuit. This feature perfectly matches the water temperature coefficient as it changes. All models are corrected to 25′C. The TC may be disabled to conform to USP requirements.

 

 

Categories : Product Updates, Technical Tips

Circuit Board Cleanliness Testing – MyronLMeters.com

Posted by 19 Sep, 2012

TweetContamination of circuit boards can bring about severe degradation of insulation resistance and dielectric strength. Cleanliness of completed circuit boards is, therefore, of vital interest. For those companies who have established circuit board cleaning procedures, the MIL Spec P-28809 has been used as a guideline for control. Now a simple “on line” test for the […]

Contamination of circuit boards can bring about severe degradation of insulation resistance and dielectric strength. Cleanliness of completed circuit boards is, therefore, of vital interest.

For those companies who have established circuit board cleaning procedures, the MIL Spec P-28809 has been used as a guideline for control. Now a simple “on line” test for the relative measurement of ionic contamination has been developed.

This fast and economical method for testing circuit board cleanliness uses an Ultrameter II™ 4P or 6P, a suitable container, and a mixture of Dl (deionized) water and alcohol. The procedure is as follows:

1. Mix a stock quantity of solution using 25 parts by volume of Dl water and 75 parts by volume of 99% isopropyl alcohol. The conductivity, measured with the Ultrameter II 4P or 6P should be a maximum of 0.166 micromhos/microseimens/cm.

2. Measure out an amount of the water/alcohol mixture equal to 100 ml per 10 square inches of circuit board surface to be tested (considering both sides of the board but not components), and add 60 ml additional. In other words: 2(L X W) (10 ml) + 60 ml = total solution needed.

3. Fill a poly “zip-lock” bag or other suitable plastic or glass container with the measured water/alcohol solution.

4. Using the measured water/alcohol solution in the poly bag, rinse out the Ultrameter II’s cell cup three (3) times, discarding the rinse solution each time. Fill the instrument cell cup a fourth time and take a meter reading. This value should be 0.166 micromhos/microseimens/cm or less and is the very clean control (or “comparison”) reading for the test.

5. Being very careful not to contaminate the PCB, totally immerse the circuit board in the solution. Seal bag. Allow it to soak for three (3) minutes with mild agitation.

6. At the conclusion of the soaking, pour the solution directly into the instruments cell cup four (4) times; take the fourth reading.

7. Compare the control reading in Step 4 with the reading taken in Step 6 (The higher the difference between the two readings, the greater the ionic contamination). Record this final extract reading for comparison with other boards tested in the same manner.

The level of cleanliness needed can be determined by each individual company.

Mil Spec P-28809 can be used as a guideline, or standards can be established based upon available data. In either event, the comparative method using the Myron L Ultrameter II will assist in the determination of that level of cleanliness.

 

 

Categories : Application Advice, Technical Tips

Saving With Automatic Rinse Tank Controls – MyronLMeters.com

Posted by 18 Sep, 2012

TweetProper rinsing is one of the most important steps in quality manufacturing or metal finishing. Plenty of low cost, good quality water for rinsing has been available in the past, so rinse water conservation has been largely ignored. Today, this is no longer true. Tap water costs have increased dramatically. Various new regulations are now […]

Proper rinsing is one of the most important steps in quality manufacturing or metal finishing. Plenty of low cost, good quality water for rinsing has been available in the past, so rinse water conservation has been largely ignored.

Today, this is no longer true. Tap water costs have increased dramatically. Various new regulations are now in effect which limit the allowable volume of wastewater. Others require wastewater treatment. Still other laws tax the amount of water going down the sewer.

These factors have all encouraged many manufacturers and platers to invest in automatic rinse tank control systems. Many platers using automatic control systems for the first time are pleased to discover a reduction in water usage of up to 80%.

This water use reduction provides two major benefits:

1. LOWER WATER BILLS

The savings possible with Myron L automatic Rinse Tank CONTROLSTIK II™ Systems are illustrated in the following table. Figures are based on a 50% water reduction rate; the minimum that can usually be expected. Exact savings depend on several variables, including the type and frequency of workloads, rinse tank size, and type of contaminant.

NOTE: 100 cubic feet of water is equivalent to 2831.5 liters/748 gallons.

 

 

 

 

 

 

2. WASTE TREATMENT SYSTEM INVESTMENT IS REDUCED.

The second major cost advantage of the CONTROLSTIK II™ System: Reducing the investment required for waste treatment equipment. Because less water is handled, smaller capacity treatment/recovery systems can be used to meet government water pollution regulations.

Generally, chemicals being “dragged in” and salts that are dissolved from work being rinsed cause rinse water contamination. These solutions ionize and can be measured and controlled by Electrical Conductivity (EC). EC measures both the total dissolved solids and the non-solid (eg: acid) contaminants, thereby giving the most correct method of control. As water contamination increases, so does the conductivity; the automatic rinse tank controls operate on this principle. When conductivity reaches the value selected as a control point, the water valve turns on to dilute the contamination. When the contaminants are reduced by the dilution, the conductivity falls and the water valve turns off.

The unit of measurement for conductivity is the micromhos (microseimens); Myron L systems are calibrated to this unit. All Myron L Rinse Tank CONTROLSTIK II Systems can be used in either normal tap water or in Deionized (DI) water tanks. The dual range sensor can be set on either the 5-500 or the 500-5000 micromhos range. The AUTOMATIC RINSE TANK CONTROL is briefly described below. All Myron L CONTROLSTIK II Systems consist of three components: Transformer Box, CONTROLSTIK Sensor, and Solenoid Valve.

AUTOMATIC RINSE TANK MODEL

Model: 597

Features

Reliable solid-state electronics in a heavy-duty, IP65/NEMA 4X Corrosion and water resistant transformer box enclosure, suitable for any plating environment.

OTHER PRODUCTS USEFUL FOR FINISHING APPLICATIONS

Also available are hand-held Conductivity & pH Instruments for “on-the-spot” water quality testing. The Conductivity and pH sensors are built in for maximum protection. The pH sensor is user replaceable. 750 Series II Monitor/controllers for continuous in-line water quality monitoring. For additional information, please refer to Myron L data sheets, or Ask An Expert at MyronLMeters.com.

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Categories : Application Advice, Technical Tips