Wednesday, December 31, 2008

Aquamatic Stager Controls Information for GE/Osmonics

Res-Kem added a significant amount of information on Aquamatic Stager Controls to our website including Product Specifications, Manuals and Ordering Guides. We wanted to make the information more easily accessible for our customers and others who use Aquamatic stager controls in their water treatment equipment.

Res-Kem uses Aquamatic Stager Controls for many of the systems we manufacture. Stager controls are used to automatically control softeners, dealkalizers, sand filters, multi-media filters, cation and anion deionizers. Also, we use these same stager controls, with a valve nest, to retrofit old Permutit, and Brunermatic multiport valves. Also, given our system expertise, we service these units in the field.

Aquamatic Stager Controls:GE Aquamatic 962 Stager Control Outside View supplied by Res-Kem Corp.

Res-Kem uses Aquamatic Stager Controls for many of the systems we manufacture. As the name implies, it is comprised of an Aquamatic Stager and an Aquamatic Control. Res-Kem uses Aquamatic valves with a variety of stager control combinations to automate the operation and/or regeneration of valve nest type water softeners and filters. Aquamatic Stager Controls are used to automatically control softeners, dealkalizers, sand filters, multi-media filters, cation and anion deionizers. These same stager controls can be used with virtually any other valve manufacturer with pneumatic actuated valves ONLY if their actuators are air/spring. These manufacturers include Keystone, Bray, George Fisher +GF+, Hayward, and Asahi. Also, we use these same stager controls, with a valve nest, to retrofit old Permutit, and Brunermatic multiport valves.

Aquamatic 962 Stager Controls:
The AquaMatic 962 stager controls combine an AquaMatic stager with an Autotrol 962 series electronic control, mounted and prewired in a NEMA-rated enclosure. When combined with a flow meter, the series 962 electronic controls provide sophisticated, demand-based water conditioning by monitoring the amount of water used. Time-based and/or external signal initiation is also available as a standard feature.GE Aquamatic 962 Stager Control Inside View showing Circuit Boards and Stager supplied by Res-Kem Corp

Aquamatic A100 Stager Controls:
This series of AquaMatic controls combines an electromechanical timer with a stager. The A100 series initiates a regeneration based on a time set on the built-in time clock.

Aquamatic A200 Stager Controls:
This series of AquaMatic controls combines an electromechanical timer with a stager. The A200 series initiates a regeneration when a signal is received from a water meter, sensor, pressure differential switch, push button or other remote device.

Aquamatic 7000A Programmable Regeneration Controller (DISCONTINUED):
These units are no longer sold. Through some careful engineering, the 7000A controller can be replaced with a Aquamatic 962 Stager Control. The Aquamatic 7000A was an electronic programmable regeneration designed to control the regeneration of filters and ion exchange processes. The 7000A was used in combination with an Aquamatic 48 Series Stager, Aquamatic 51 Series Stager, or Aquamatic 58 Series Stager.

Aquamatic Stager: GE Aquamatic Series 58 Stager for a 962 Stager Control unit supplied by Res-Kem Corp.

Added are product specifications on Aquamatic Stagers. A stager is a motor-driven rotary multiport pilot valve, which is used to control a set of individual diaphragm valves in a predefined sequence.

There are five stager designs available:

  • Aquamatic Series 48 brass stager with six ports. The 48 stager can control typical softener or filter systems as well as sequential backwash filters.
  • Aquamatic Series 51 brass stagers with eight ports. Used for more complex systems such as non-standard softeners, twin alternating softeners or filters.
  • Aquamatic Series 96 brass stagers with eight ports. Used for more complex systems such as non-standard softeners, twin alternating softeners or filters.
    The 96 stager design is similar to that of the 51, but is rated for 250 psi (17 bar) and used for high pressure systems.
  • Aquamatic Series 58 PVC stager with sixteen ports. Used for more complex systems such as non-standard softeners, twin alternating softeners or filters.
  • Aquamatic Series 59 brass stager with sixteen ports. Used for more complex systems such as non-standard softeners, twin alternating softeners or filters.

    Given our expertise building systems with Aquamatic Stager Controls, we can help you select the correct parts, select/troubleshoot stager controls or service stager in the field.
  • Thursday, December 18, 2008

    Water Analysis Could Have Saved $57,000

    In the white paper, "A $150 Water Analysis Could Have Saved $57,000 in Capital and RO Cleaning Costs" by Joseph Urbans-Sales Engineer at Res-Kem Corp., he details how a water analysis is extremely important in the design phase of a water treatment plant design.

    The paper shows after spending $52,000 in capital and installation for water treatment equipment, technical and service personnel from Res-Kem Corp were called in to diagnose a major problem with a three week old reverse osmosis (RO) system specified, built, and installed by others. Upon investigation, an inlet water analysis may never have been done, or at least no one could produce the analysis used to originally size the plant. It appears the engineering firm sized and designed this project without one.

    The Costs:
    If the system had been designed correctly from the start, Res-Kem conservatively estimates the savings to be $57,000:
  • Total capital and installation costs of original system $52,000
  • Membrane cleaning costs of $5,000

    In addition, if the RO membranes cannot be cleaned, the cost will be $15,000 for new membranes plus installation service.
  • Thursday, December 11, 2008

    Frozen Ion Exchange Resin

    During the winter months here in the Northeast we are often asked about how to handle frozen ion exchange resin. The best way to avoid frozen resin is to make sure the ion exchange resin is shipped in a climate controlled reefer type van. There is usually additional expense involved with use of this truck but it is an option to consider if you are located in a cold climate and need to install the resin upon arrival at your plant.

    How can I avoid freezing ion exchange resins?
    You can avoid the frozen ion exchange scenario by making sure your vendor doesn't ship on a Friday. Shipments that go out on Friday often will sit over the weekend allowing enough time for the resin to freeze. That's not to say the resin wouldn't freeze over night if the vendor shipped on a Monday and delivered on Wednesday. You just cut the odds of having frozen resin delivered.

    What do you do if the resin is frozen?
    On Page 5 of a Purolite brochure addressing transportation and packaging of ion exchange resins, Purolite states:

    "Although it has been found that Purolite Resins will withstand temperatures as low as -40 degC, (-40 degF), successive thawing and freezing may damage the product, and/or the packaging. Hence it is recommended that the resins are stored above 0 degC, (32 degF). If for any reason resin becomes frozen it should be left to thaw out gradually. No attempt should ever be made to free frozen mechanically. If it is anticipated that it will be necessary to handle resin at sub-zero temperatures, the resin may be conditioned with saturated brine prior to storage. During transportation of resins precautions should be taken to avoid the extremes of temperatures as outlined previously. If product becomes frozen during transportation, thawing should take place gradually, with out any physical interference."

    So if you have frozen resin, put it in a sunny spot and let it thaw, don't go at it with an ice pick!

    Monday, December 08, 2008

    Triple Softener System for Steam Heat Peaking Plant Sized for 750 gpm Flow

    Here is another example of number of the industrial, commercial, residential, and/or residential water treatment systems being designed, assembled, shipped and installed by Res-Kem engineers, pipefitters, and/or contractors within in the past few months.
    Res-Kem Corp. Triple Industrial Softeners with 54-inch diameter vessels being prepared for shipment from our facility in Aston, PA
    A Boston steam heating company needed to replace their aging Permutit triple softening system. These units, with Permutit multiport valves, had reached the end of their life.

    Existing Permutit Triple Softener system using Permutit multiport valves for operation and regeneration at steam heat peaking station
    Res-Kem was selected based upon the recommendation of a sister company in Cambridge, MA which had a Res-Kem triple softening plant at their facility. Since the Permutit multiport valves are no longer commercially available, the Res-Kem design used Aquamatic valves instead of the Permutit valves. Also, it appears the size of the existing Permutit units was too large for the plant flow requirements. Res-Kem used a peak design flow from the softeners of 750 gpm. Upon careful review and competitive bidding process, Res-Kem was selected to provide the replacement system.

    Several design changes from the standard Res-Kem industrial softener design were needed to meet the unique requirements of this peaking plant. In particular, the valves needed to be changed from our standard normally open (air to close) actuation to normally closed (air to open) actuation. This was done so the valves will fail closed in the event of loss of air pressure. Normally air pressure is used to stop the water flow during periods of downtime. In this case, when the plant is not being used to generate steam, virtually all power is turned off including tha air compressors to save energy.

    Res-Kem Corp. Industrial Softeners with 54-inch diameter vessel prior to shipment from our facility in Aston, PA. System uses normally closed (air to open) Aquamatic valves and incorporates a brine distributor in vessel.

    With precise drawings by Res-Kem engineers, accurate assembly by Res-Kem pipefitters, and excellent coordination with the site mechanical contractor, the water softeners are being rapidly installed. Commissioning is scheduled for the week of December 15, 2008 only 5 business days from shipment! When our start-up engineer visits for operator training, we will post a picture of the installation.

    Triple Sand Filters Shipped and Installed Treat Sized for Peak Flow of 1000 gpm

    It has been a very, very busy couple of months at Res-Kem. Systems of all sizes have been designed, built, shipped, and installed for industrial, municipal, commercial and residential customers throughout the US. As a recent example, on November 20 we shipped a triple sand filter to a customer on the California/Arizona border.

    Res-Kem Corp Triple Sand Filter leaving plant in Aston, PA on November 20, 2008
    With precise drawings by Res-Kem engineers, accurate assembly by Res-Kem pipefitters, and excellent coordination with the site water and wastewater contractor, the sand filters were rapidly installed and commissioned by December 8, 2008! Please note, there was shipping time of 3 days and a Thanksgiving holiday in between!

    Res-Kem Corp Triple Sand Filter installed at site on California/Arizona border showing 823,000 gallon reservoir tank on December 8, 2008

    The triple 84-inch diameter sand filtration system is sized to treat a peak flow of 1000 gpm. The sand filters are used to treat all of the potable water going to an 823,000 gallon reservoir tank after chlorination. Most of the storage capacity is for fire water requirements.

    Saturday, November 15, 2008

    Dealkalizer Control Upgrade

    The Problem:
    A seafood processing plant called Res-Kem Corp to service their Brunermatic Dealkalizer. Their problem was of water running to drain during backwash and rinse stages. To repair the valve, Res-Kem service personnel would need to replace or rebuild the backwash outlet port and rinse outlet port.

    The Analysis:
    The Res-Kem service manager noted during the site visit that the control on the dealkalizer is no longer manufactured and the caustic pump was not functioning. With a dealkalizer, caustic can be fed during the regeneration cycle to enhance dealkalizer performance. The addition of caustic to the brine gives greater capacity to the Type II strong base anion ion exchange resin used in the dealkalization process. The following shows the increase in dealkalizer capacity with the addition of caustic to the brine regeneration step.
    Dealkalizer capacity differences of brine vs brine caustic regeneration. Charts are from Purolite A300 brochure. See

    The Solutions:
    Having seen this problem before, the Res-Kem service manager suggested the customer consider an upgrade to a current design that incorporates the Signet Flow Sensor and caustic pump. Res-Kem uses the Aquamatic 962 Controller and Stager. The Aquamatic 962 controller is a programmable electronic control with a relay that can be used to signal the chemical feed pump. The cost to repair the existing caustic pump exceeded the cost of a new one and the customer was happy to learn the pump manufacturer they use elsewhere in the boiler house could be used in conjunction with the new Aquamatic 962 controller.

    The Benefits:
    This simple upgrade to the existing dealkalizer benefits the customer by:
  • Allowing use of their standard pump manufacturer and enabling them to keep "standard" repair parts on hand
  • Allowing continued successful operation of the existing dealkalizer
  • Gets them back to the original design - automatic operation of the dealkalizer.
  • Monday, October 27, 2008

    Condensate Polisher Savings of 23% Realized Through Value Engineering

    The white paper, "Condensate Polisher Savings of 23% Realized Through Value Engineering", shows how a value engineering team comprised of personnel from a well-known university, Res-Kem Corp, and a mechanical contractor yielded the best system for the money.

    These savings substantially improved the return on investment. This was accomplished without making any compromises on the installation costs, reliability of operation, or desired operating efficiency of the powerhouse.

    The Problems:
    All the qualified bids exceeded the set aside level of funding. During the time lag between project approval and initiation of the bidding process, a number of variables arose which collectively now jeopardized the project in its entirety.
  • The cost of stainless steel, while recognized to be escalating, continued
    to climb beyond all reasonable expectations.
  • The university’s internal cost of capital was adversely affected by a tightening of available funds within the credit market. Almost immediately, the university comptroller put the project on hold and demanded an even higher return on investment in order for the project to proceed.

    The Solution:
    In an attempt to move the project forward, it was decided the university utility manager would work directly with the condensate polisher manufacturer and the winning bid mechanical contractor to see how best to value engineer the product offering. The targeted goal of the value engineering team was to reduce the purchase price of the condensate polisher by a minimum of twenty percent. This together with some labor saving initiatives taken on by the mechanical contractor installing the system would hopefully rescue the project.

    Value Engineering Study Items and Savings

    Downsize Vessel Size -- 4% Savings

    Retain stainless steel vessel -- 0%

    Retain C-150 resin -- 0%

    Modify external piping -- 13% Savings

    Modify control valves -- 6% Savings

    Total Value Engineering Savings -- 23%

    As shown in the above summary, the benefits of joining together a team of
    knowledgeable and experienced individuals can be readily apparent. This is particularly true when the individuals come to the task with complementary but differing skill sets combined with a shared sense of purpose.
  • Wednesday, October 01, 2008

    Stainless Steel vs Lined Carbon Steel Vessels for Industrial Water Softeners

    Recently we received the following question from a prospective customer:
    We are trying to decide whether to purchase stainless steels or lined carbon steel vessels for our industrial water softeners. We currently have old stainless steel units we inherited from a sister plant. These tanks are corroded. What is Res-Kem's position on buying stainless steel versus lined carbon steel tanks for our water softeners?

    Our Answer:
    Res-Kem is of the opinion that a stainless steel vessel is "usually" the more cost effective alternative when compared to a lined carbon steel vessel for water treatment applications. This assumes that the end user has the financial capacity to handle the higher upfront cost and that the vessel internals are properly designed. We added the word "usually" as the possibility of stainless steel chloride corrosion can be problematic in high temperature applications or those with improperly designed vessel internals.

    Used with properly functioning internals, stainless steel vessels will last for a very long time on a simple water softening application. A carbon steel vessel on the other hand is very much dependent on the condition of the vessel lining. Eventually every lining will develop a pin hole failure leading to corrosion, a subsequent leak, and full vessel failure. Obviously this is not a concern with unlined vessels constructed of stainless steel.

    In the case of the corrosion of the existing stainless steel vessels at this customer, there are two explanations for the corrosion they are experiencing. For starters they are not diluting the regenerant brine. This only increases the chloride levels during the regeneration cycle. It's worth mentioning that ordinarily any water softener is only subjected to high chloride levels during the 30 minutes or so as brine is introduced to the vessel. At this customer, not only is the brine saturated, but there is little assurance that the design of the internals gets all the brine out during the following rinse steps. Should this be the case, the bottom dome of the vessel would have a stagnant brine solution remaining in it well after the regeneration cycle is finished. This would particularly enhance the corrosion process especially if the water contains an appreciable amount of dissolved oxygen. One can only assume this condition applies at this customer and things are exacerbated with the higher concentration of brine being used.

    It's worth pointing out that General Water, the service DI arm of Res-Kem has a rental fleet of well over 200 skid mounted DI exchange vessels. All are 36" diameter and all are constructed of stainless steel. The decision to purchase stainless vessels over lined carbon steel was not done because we like to spend money. It was done as it's a good investment over the long haul.General Water Stainless Steel 30 cubic foot Service DI Vessel

    Tuesday, September 30, 2008

    How to Measure pH Accurately in Steam Condensate

    Keeping within ASME guidelines for total iron in boiler feedwater below 0.1 ppm and total copper below 0.05 ppm copper requires attention to the maintenance of steam traps, knowledge of the metallurgy of the steam/condensing equipment in the steam distribution system and in particular the pH of return condensate.
    Steam Condensate Sample Cooler by Res-Kem Corp

    When measuring pH in condensate, it is important to cool the sample with an in-line water sample cooler to minimize the CO2 flashing off from the sample. When the CO2 flashes off it is not present in the condensate sample so it will not form carbonic acid. Without carbonic acid present, the pH will be measured with a false high pH. The difference between in-line cooled condensate samples and ambient cooled condensate temperatures can be 2.0 or more pH units. This difference in pH will dramatically increase the corrosion rate.

    The following chart shows how equipment with large steam demands and therefore condensate flow with elevated CO2 levels will likely have elevated corrosion rates.
    The Impact of CO2 and Flow Rate on Corrosion

    In addition to ensuring proper measurement of pH, an in-line water sample cooler enables safe handling of the high temperature condensate. Water sample coolers are available in carbon steel or stainless steel. Certain sample cooler models have easily accessible coils that can be cleaned or replaced as needed.

    Monday, September 15, 2008

    Uniform Particle Size Ion Exchange Resins

    We received notice today that Purolite Ion Exchange Company will no longer be selling the anion resins, A-300 and A-400. These resins will be replaced by Purofine PFA-300 and PFA-400. The Purofine line of resins is uniform particle size (UPS). Dow did this a number of years ago when they introduced the Marathon grade of Dowex Ion Exchange Resins. The Marathon line of Ion Exchange resins pretty much replaced the entire line of standard Gaussian resins.

    In general there are many advantages to using UPS resins.

    Higher Regeneration Efficiency:
    According to Dow regeneration is the least efficient step in the ion exchange process. Large beads regenerate more slowly than small beads. The typical Gaussian mesh range is 16-50 whereas UPS resins are 30-40 mesh, a much tighter specification. The UPS resins have a smaller average particle diameter and will regenerate more quickly resulting in more efficient use of regenerant chemicals. So you use less and get a higher operating capacity.

    Greater Operating Capacity
    The kinetics of the UPS resins is more favorable than that of Gaussian. "This leads to an increase in usage of the entire resin capacity from the top to the bottom of the bed...the net effect of the more efficient higher throughput."

    Better Rinse Efficiency:
    Excess regenerant chemicals diffuse more quickly from within the beads, thus decreasing the time required to reach the specified endpoint. Faster rinse times trim water and wastewater disposal costs.

    Reduced Leakage:
    The result of these increased efficiencies is an increase in production of pure water for a longer time since the leakage endpoint is extended

    Better Separations for Mixed Beds:
    For many years now Res-Kem has been advising customers to use UPS resins in their mixed bed units. In fact, our sister company, General Water Services, uses UPS resins to service their high-purity customers. One reason for doing so is better separation prior to regeneration. With Gaussian resins, the smaller cation beads are easily trapped with the larger anion beads. With better separation you get lower leakages, a better regeneration and greater throughput.

    Operating Considerations:
    Backwash Rates are lower when using UPS resins. Consult the engineering graphs, Dow Marathon, Purolite Anion or Purolite Cation, prior to installation or contact a qualified equipment manufacturer to determine the changes required when upgrading to Uniform Particle Size resins.

    Helpful Links:
    I've included a couple helpful links from Dow and Purolite with more detailed information if you'd like to read more about the advantages of using UPS resins in your water treatment system.

    Here is information from Dow:
    UPS (Uniform Particle Size): The Key to Greater Productivity in Ion Exchange

    Here is information from Purolite:
    Notice of Product Replacement for Purolite® A300 and A400

    Thursday, September 11, 2008

    Setting Brine Tank Refill Time on Fleck Softener Valve

    The Pentair® Fleck® multi-port softener valve controllers, electronic versions SE, XT, XTR and SXT and non-electronic versions, are very flexible allowing for customization of the regeneration cycle of the water softener. This flexibility requires that you know a little bit about the system and a simple calculation -"Brine Refill Time". Although a simple calculation, "Brine Refill Time" is often misunderstood.

    The "Brine Refill Time" is easy to calculate and is the same regardless of valve and controller type.

    The following values are based on the design of the softener and valve.

    T = Brine Tank Refill Time (minutes)
    X = Brine Line Flow Control Rating (gpm)
    Y = Salt Dosage sometimes called Regeneration Level (lbs/cuft)
    Z = Amount of Resin in Softener (cuft)

    In order to set the time you need to know the concentration of saturated brine

    C = 2.6 lbs/gallon = Concentration of Saturated Brine

    So the equation is:

    T = (Y * Z)/(X * C)


    X = 0.5 gpm
    Y = 12 lbs/cuft
    Z = 2.5 cuft

    T = (12 * 2.5)/(0.5 * 2.6) = 23 minutes for brine refill step

    Friday, August 29, 2008

    Parts for Solo, Solomatic, Bruner, Brunermatic, Permutit, Aquamatic, Culligan HiFlow Multiport Valves & Others

    Routinely, Res-Kem receives requests for quotes for water treatment systems and their replacement parts. One area that frequently needs explanation is replacement parts for multi-port valves including Solo®, Solomatic®, Bruner®, Brunermatic®, Permutit®, and Aquamatic®.

    We get questions like:

    Please quote the following.:

    AQUAMATIC valves with 6 ports total. 5 ports are 3". One in the rear and 4 in cross form. The 6th port is 2", which is the regenerant inlet port.

    The fluid flowing through the valves is composed as follows:

    1) Hydrochloric acid (HCL) 32% at ambient temp.
    2) Sodium Hydroxide NaOH (caustic soda) 50% at ambient temp.
    3) Water at ambient temp.

    4) Picture of valve attached.

    Aquamatic Multi-port Valve

    Another Question:
    I have a Kisco water softener system with Aquamatic Solomatic Valves. The model number of the system is TWSKOM-300. I need replacement valves. What can I do?

    Res-Kem Solution:
    As a service company, Res-Kem frequently comes across many different water treatment systems, which have Solo, Solomatic, Bruner, Brunermatic, Permutit and Aquamatic Multiport Valves as well as other manufacturers. Unfortunately, many of these valves and controls for the valves have been discontinued or parts are extremely difficult to find, (which may be due to industry consolidation), and those parts which are available are very expensive. The Res-Kem solution is to replace the multi-port valves with a "valve nest" and an appropriate control system.

    A valve nest performs all the functions of a multiport valve using Aquamatic diaphragm, Keystone butterfly, or other valves as specified by the customer. Using a standard layout with flexibility to account for various tank sizes, a valve nest is a very cost-effective alternative to a multi-port valve.

    Valve nests can be supplied in a wide variety of materials: Cast iron valves with steel piping, Bronze valves with copper piping, plastic valves with PVC piping, stainless steel valves with stainless steel piping. They can be adapted to filters, softeners, dealkalizers, demineralizers and deionizers.

    Thursday, August 07, 2008

    Type II Anion vs Type I Anion: Ion Exchange Resin Analysis Yields Regeneration Savings

    Res-Kem is a supplier of ion exchange resins from several vendors including Purolite. Res-Kem is often asked to diagnose a potential ion exchange resin problem. Depending upon the resin type, cation, anion, or mixed bed, cost and length in service, it may make sense to sample the resin and test for parameters that can identify what has caused the resin not to perform and a potential remedy.

    One recent example of the value of an ion exchange resin analysis are the results of two anion samples sent to Res-Kem. The customer was noticing:

  • More frequent regenerations
  • Increased chemical usage
  • Longer rinse times This resulted in a much higher cost to produce water for use.

    They needed a solution.

    Ion Exchange Resin Analysis Reports:

  • Ion Exchange Resin Analysis Report for Train A
    Ion Exchange Resin Analysis Report for Train B

    Discussion of Resin Analysis (Written by Ted Begg of Purolite):

    Train A & B strong base anion resin analysis concluded the samples are Type II Strong Base Anions, equivalent to Purolite A300. Both samples exhibited dramatic loss in strong base capacity and severe organic fouling. Typical Type II anions will have 90% strong base capacity when new, however, it is not uncommon to see severe reduction to the levels observed, ~ 60%, when the resin is continually subjected to temperatures well in excess of 95 degrees F. Strong base capacity is responsible for silica removal. As this capacity is lost, throughput to silica break gets lower and lower with cost of caustic for regeneration steadily increasing. Given caustic is approaching $1000/ dry ton, lost throughput due to resin degradation comes at a very high cost.

    The organic fouling noted is severe and is likely contributing to lost throughput and increased rinse volume (fast rinse). The organics on the resin pick up sodium during caustic regeneration, which slowly elutes off during the fast rinse. Therefore the increased rinse volume.

    The Demineralization System:

    This plant was designed to mix returned hot condensate to the finished water make up storage tank. This water is used for boiler feedwater and as well as for regeneration. While the heated water is beneficial for boiler feedwater, it is not good for regeneration of the anion resins. This water can approach and possibly exceed 130 degrees F. The Type II strong base anion resin temperature limit is stated by manufacturers at 105 degrees F, however, it is more prudent to maintain the limit to a maximum of 95 degrees F. Given the plant operating conditions and the condition of the anion resin, we recommended that the anion be replaced with a more temperature stable product. A Type I porous anion resin with uniform particle size distribution is recommended as a replacement. The product, PFA400, is stable up to 140 degrees F and is more resistant to organic fouling than the incumbent resin. In this case longevity of the resin will improve. The throughput capacity of PFA400 will approach the incumbent resin as well. Thanks Ted for the detailed discussion above of the analyses.

    Our Conclusions and Observations:

    The conclusion is using a Type II anion in place of a Type I, where low silica water is required and the system can run above 95 degrees F, is a misapplication for the reasons stated above which are:

  • Less stable at higher temperatures
  • Strong base sites break down more easily breakdown to weak base sites
  • Lower capacity for silica

    So how does this misapplication happen? The selection of the ion exchange resins for a demineralization system generally occurs many years before a system is started up. Depending upon the perceived complexity of the water treatment system which includes the demineralization system, an engineering company may be specifying the demineralization system components including the resins as well as a whole host of other pieces of equipment. Then these specifications will be bid on by a short or long list of OEM's each of whom wants to get the job. Most will bid to the specs, but others may suggest a cheaper alternative.

    One common area to shave money from the whole job is to skimp on the demineralization system in particlar the anion system. When lowest installed cost is the driver, sometimes Res-Kem sees equipment companies selling deionization systems using a Type II anion resin. The reason they promote the use of a Type II anion is the anion portion of the system is smaller. Because the Type II anion resin has about a 10% higher initial capacity than a Type I, the equipment needs 10% less of the expensive anion resin and the size of the anion tank is smaller. The end result is several months after commissioning and transfer of the equipment from the OEM to the user, the problems begin. By then, the low budget OEM will be on to their next project and will often walk away from your problem.

    Res-Kem believes the moral of the story is work work with a knowledgeable OEM with experienced personnel who will recommend the best equipment for your application and will stand behind their equipment when installed.
  • Thursday, June 26, 2008

    Water Neutralization Saves $23,000 Annually

    Res-Kem has published another white paper on water treatment. This next one is entitled "Bucking the Industry Trend… Simple Change to Water System Saves New Jersey Manufacturer $23,000 Annually"by Kevin Preising.

    This paper details how the addition of an acid water neutralizer (5.5-6 pH) as a pre-treatment step to the Reverse Osmosis system saved over $23,000/year in downstream operation expenses at a New Jersey manufacturing plant. The acid water neutralizer, with an investment of less than $7,000 and operational and labor costs of only $700/year, has a Return on Investment of less than three months. While not a solution for all systems with reverse osmosis and high acidity, discussing neutralization with a qualified vendor can save Electrodeionization and/or Service DI operational expenses.

    What is really interesting about this paper is it shows how a simple acid water neutralizer, properly applied, can save a considerable amount of money on operating expenses.

    Having been in the water treatment industry for two decades, I have seen the trend in the water treatment industry towards more and more complex water treatment technologies and discounting past knowledge as old-fashioned. Often lost is a true understanding of water chemistry by some current "industry experts" and the simple, economic solutions to water treatment problems.

    Please take a look and tell us what you think!

    Tuesday, June 03, 2008

    Activated Carbon: Mesh Size

    We are often questioned about the differences between 1240 (12 by 40) mesh activated carbon and 830 (8 by 30) mesh activated carbon. The 1240 mesh activated carbon is smaller than the 830 activated carbon.

    The screens or the mesh sizes are different. The 12 mesh screen has 12 openings per square inch 12 across and 12 down. The 40 mesh screen has 40 openings per square inch, 40 across and 40 down. Obviously the "holes" of the 12 mesh screen are larger than the "holes" of the 40 mesh screen. It follows that the holes on an 8 mesh screen are larger than 12 and 30 mesh holes are larger than 40 mesh holes.

    Activated Carbon Particle Size Table Courtesy of Calgon Carbon Corporation

    If you would like a laminated card with this guide, contact Res-Kem.

    As part of the manufacturing process the activated carbon companies pass the carbon through various screens to meet the specification.
    Particle Screening System Courtesy of Calgon Carbon Corporation

    So if you look at 1240 mesh activated carbon, it shouldn't have particles larger than 12 mesh or smaller than 40 mesh. The 830 mesh activated carbon shouldn't have particles larger than 8 mesh or smaller than 30 mesh.

    What difference does this make to the user of the activated carbon? The most commonly used activated carbons for residential POE (point of entry) systems, commercial and industrial systems are 830 and 1240 mesh. We use 1240 mesh activated carbon because it has greater surface area and provides excellent chlorine and organics removal. Because the activated carbon filter acts as a mechanical filter in addition to removing chlorine and adsorbing organics, it will accumulate particles of dirt or crud at the top of the bed. An activated carbon filter is backwashed on a regular basis to remove this and prevent pressure loss across the bed.

    In instances where the water contains more turbidity or crud, an 830 mesh activated carbon may be used. Having larger particle size than the 1240 activated carbon, the filter containing 830 mesh activated carbon won't need to be backwashed as often. However, as the particle size increases from a 1240 mesh activated carbon to an 830 mesh carbon, thereby decreasing the backwash flow rate, adsorption capacity will generally decrease.

    When we specify an activated carbon it's important to know the water source. If it's city water or well water from a potable source, we can assume there is little if any turbidity and use of a 1240 mesh activated carbon will work well. If an industrial plant is taking water directly from a river or lake there may be disruptions to the clarification system that may cause excess crud or turbidity. In these cases we see the use of 830 mesh activated carbon.

    Here is a full glossary of activated carbon definitions.

    Wednesday, May 21, 2008

    FILMTECTM BW30LE-440 and BW30LE-4040 RO Elements to be Discontinued

    The Dow Chemical Company recently sent a discontinuation notice for the FILMTEC BW30LE-440 and BW30LE-4040 which have been an industry standard for many years. Dow will not take orders for the current LE elements after May 30, but will honor any orders on the books even if shipment is not until the end of the year.

    The good news is FilmTec Corporation has developed a new Low Energy, LE, membrane. FILMTEC elements rolled from this LE membrane have the highest active membrane areas, and operate at lower pressure reducing operating costs.

    FILMTEC LE-440i:
    This RO membrane element replaces the FILMTEC BW30LE-4040 RO Element. The FILMTEC LE-440i has 440 square feet of RO membrane which is the highest active membrane area in the industry.

    The FILMTEC LE-440i element:
  • Has 10% higher productivity than the FILMTEC BW30LE-4040
  • Operates at lower pressure
  • Maintains High Rejection
  • Minimizes operating expense
  • Reduces total cost to produce industrial, commercial, or municipal water
  • Incorporates iLECTM interlocking endcaps minimizes O-ring leaks which improves permeate quality

    FILMTEC< LE-400 element:
    This RO membrane element replaces the FILMTEC BW30LE-440 RO Element. The FILMTEC LE-400 has 400 square feet of RO membrane.

    The FILMTEC LE-400i element:
  • Has higher salt rejection for better permeate quality
  • Operates at lower pressure
  • Minimizes operating expense
  • Reduces energy cost to produce industrial, commercial, or municipal water
  • Wednesday, April 23, 2008

    Water Softener Is Not Producing Soft Water

    Your customer's water softener is not producing soft water. The brine tank may be filling with water.

    A water softener is used to protect clothes from iron and manganese staining, plumbing fixtures and appliances from mineral deposit damage, and reduce household chemical usage. Your customer has spotting on their glassware, cloudiness on shower stalls, and dingy clothes. Also, they may be getting iron and manganese staining on their clothes, appliances, and bathroom fixtures.

    Possible Solution:
    The most common problem is the brine used to regenerate the softener is not getting into the unit. The first place to look for a problem is in the "brine injector". Just like the water aspirator you used in elementary chemistry class to make a vacuum, the water softener valve uses water flow through venturi across an orifice to pull brine from the brine tank into the water softener. If anything plugs the orifice, the brine will not get into the water softener. In the following video, Michael Urbans, Technical Manager for Res-Kem's Residential Segment, shows how to clean or repair the brine injector on a Pentair® Fleck® 7000 multiport softener valve.

    Thursday, April 10, 2008

    Harmsco Cartridge Filter and Filter Housings

    The Harmsco® industrial cartridge filter and filter housing product line is now available from Res-Kem Corp. Res-Kem is proud to be a master distributor of the entire Harmsco® industrial cartridge filter and filter housing product line including:
  • Harmsco® HIF Series Up-Flow Cartridge Filter and Filter Housings
    Harmsco HIF Series Up-Flow Cartridge Filter and Filter Housings
  • Harmsco® Hurricane® Combination Cyclone Separator and Cartridge Filter
  • ASME Code Harmsco® HUR-Series Hurricane® Filter Housings with Swing Bolt Closures
    ASME Code Harmsco HUR-Series Hurricane Filter Housings with Swing Bolt Closures
  • Harmsco® WB-Series WaterBetter® Single Cartridge Filter Housings
    Harmsco WB-Series WaterBetter Single Cartridge Filter Housings

    Standard features of the Harmsco product lines are:
  • NSF Certifications
  • FDA Grade Materials of Construction
  • Electropolished 304 Stainless Steel
  • Failsafe Top Lid Closure Utilizing Multiple Fasteners
  • Top Lid Design / Safest Closure On The Market
  • Patented Up-Flow Filter Housing Design
  • Vent free
  • No cross-contamination of "contaminated" and "clean" fluids

    Here is the link to the complete Harmsco industrial product line.
  • Tuesday, March 04, 2008

    Save $91,000 Annually In Low Pressure Boiler Water Treatment Chemical And Fuel Costs Using a Dealkalizer

    A white paper entitled "Save $91,000 Annually In Low Pressure Boiler Water Treatment Chemical And Fuel Costs Using a Dealkalizer" was written by Kevin Preising a Sales Engineer at Res-Kem Corp.

    This white paper explains how dealkalization of boiler feedwater improves boiler steam/condensate systems reliability, fuel savings, and chemical savings. The Return on Investment, ROI, is substantially less than one year when a dealkalizer is added to an existing boiler feedwater plant with a conventional sodium cycle water softener - deaerator pretreatment.

    Annual chemical savings are over $76,000 and "cycle-up" energy savings are over $15,000 savings using a dealkalizer with chloride form anion ion exchange resin. Reductions in condensate piping replacements can add further cost savings and will make the ROI even more attractive. In applications where neutralizing amine concentrations are limited by FDA regulations, the dealkalizer can be used in conjunction with reduced feed of neutralizing amines, achieving an optimized solution of reduced chemical feed with improved return condensate pH numbers.

    The goal of this discussion is confined to the addition of a dealkalizer post water softener.
    The results of adding a dealkalizer are:
    - Minimized waterside scale formation
    - Minimized boiler-carryover
    - Minimized boiler blow down through increased boiler cycles
    - Increased return condensate pH values - thereby reducing the need for neutralizing amine chemical feed to control corrosion in the condensate.

    Monday, February 25, 2008

    Ion Exchange Resin Disposal

    Recently a customer asked us what to do about getting rid of the old resin after replacing it with new. This is a common question we get all the time.

    In general we can assume the following:

    Municipal or City Treated water contains little or no contaminants that are harmful to drink; therefore, it is unlikely the used resin has any contaminants on it to prevent it from being land filled as ordinary trash.

    Well water and untreated surface water supplies may contain contaminants that can remain on the resin after regeneration. These contaminants are usually metals and are found on the cation resin. They may include but are not limited to lead, copper, and arsenic. For more specific information about contaminants we recommend this site.

    How to dispose of used ion exchange resin is determined first and foremost by state and local government agencies. Regulations do vary from state to state. To satisfy local regulations it is recommended that you or your environmental manager call your regular waste removal company and ask them what to do. Most likely you will be asked to provide a TCLP test (Toxicity Leachate Characteristic Procedure) for your particular ion exchange resin, see attached pdf file for more specific information about this test.

    Most likely the waste removal company will ask for an MSDS on the ion exchange resin you want to throw away. MSDS for most ion exchange resins can be found on the Res-Kem website using these links:

    As part of our rebed service (service to change out spent ion exchange resin or activated carbon) Res-Kem will arrange for proper disposal of spent ion exchange resin or activated carbon on your behalf. This assumes we are providing turnkey removal and installation and the ion exchange resin or activated carbon is purchased from Res-Kem Corp. Sorry, we don't handle hazardous rebed applications.

    TCLP Fact Sheet from EHSO

    Friday, January 25, 2008

    How to Correctly Size a Sodium Cycle IX Condensate Polisher

    Problem: Customer Can't Get Enough Flow through Condensate Polisher => How to Correctly Size a Condensate Polisher

    Customer called to state they couldn't get enough flow through their new condensate polisher. During the service visit, it was determined that the Deaerator and Condensate system was not being operated in accordance with Best Practices Procedures presented by the US Department of Energy's Office of Industrial Technologies, Energy Efficiency and Renewable Energy.

    In this case the customer was feeding softened make up water into the Condensate tank along with the returned condensate, directing this water through the condensate polisher, then sending to the Deaerator. A Sodium Cycle Ion Exchange Condensate Polisher is typically sized and designed to treat only returned condensate, not to heat up make up water. In this case the polisher needed to handle both the make up and returns. It was never sized for this.

    Sodium cycle ion exchange condensate polisher sized to treat boiler make-up and steam condensate return

    Normally, the softened make up water goes to the inlet of the deaerator, is heated by steam to remove the dissolved gasses, stored in the deaerator storage tank and sent to the boiler. The low-pressure condensate goes to a condensate receiver, through a condensate polisher and sent to the deaerator storage tank.

    Most likely, the customer was thinking the condensate return, which is hot, would heat up the make up water before going to the deaerator, thus saving energy and steam. Conventionally, deaerators are designed to take cold softened make up water and heat it up in the steam chamber to remove oxygen and CO2 before sending it to the boiler.

    The best way to save energy would be to install a Boiler Blowdown Heat Recovery System. This consists of a Blowdown Flash Tank and Heat Exchanger. Simply put, with this system the boiler blowdown water goes to a Flash Tank, where the pressure is reduced from the boiler operating pressure to the Deaerator operating pressure; typically 5 psig (228 deg F). When this blowdown water pressure is reduced, most of the water flashes to steam. The steam is directed to the deaerator steam inlet. The remaining blowdown water goes to a shell and tube or coil type heat exchanger, which is used to heat the softened make up water prior to going to the deaerator. The heat exchanger also reduces the blowdown water to safe and acceptable temperature levels for drains.

    Separate from this, the condensate return water, having traveled through the myriad of piping, contains iron (crud) and some hardness and needs to be "polished" before being recycled back to the boiler. The condensate polishers are designed to handle only the returned condensate, which is a percentage of original make up water. When sizing up a condensate polisher we need to know the percentage of make up water that is "returned". It is only that percentage we are concerned about when we size up the condensate polisher.

    Thus, a basic system would look like this:
    Sodium cycle ion exchange condensate polisher sized to treat just the steam condensate return

    The better energy saving system (as described above) would look like this:
    Sodium cycle ion exchange condensate polisher sized to treat steam condensate return with additional energy savings using a flash tank and preheating the softened makeup water

    A condensate polisher is used in addition to this Boiler Blowdown configuration.

    Use of a condensate polisher and a good chemical treatment program enables the customer to use less make up water and energy. When considering use of a condensate polisher it's important to size it for treatment of the condensate only.

    For more information about energy savings and Boiler Blowdown Systems see attached pdf files that the government has made available via the Internet.

    US Department of Energy Steam Tip Sheet - Minimize Boiler Blowdown

    US Department of Energy "Boiler Blowdown Heat Recovery Project Reduces Steam System Energy Losses at Augusta Newsprint" - Best Practices Technical Case Study