Friday, December 29, 2006

Boiler Feed Water Flow Rate Requirements Chart

We received a request for proposal today for "a water treatment system to treat the water going into my dual 194 HP steam boilers".

Start of an Answer:
The first thing we need to do is estimate the amount of water that will be used. The question is how?

After you work in any industry for many years, everyone collects their favorite charts, rules of thumb, "crib sheets", etc. They come out of drawers, filing cabinets, binders, etc. as a result of the question and follows the statement "Don't you have this chart??"

This morning, I was given one of these charts from one our "learned gentlemen" (as he wants to be referred to as) and felt it would be great to share this boiler feed water flow rate requirements chart. I wish we knew the source of this data, but as is often the case, it was copied too many years ago for anyone to remember. This chart relates boiler horse power to the flow rate in gallons per minute and pounds per hour. In this case, we need a demineralizer or softener rated for a maximum flow rate of 28 gpm. It will be less depending upon how much condensate is returned.

The next part of this question is what water quality is needed for the application. The steam pressure and steam boiler manufacturer will help determine what the water quality needs to be. Stay tuned.

Thursday, December 28, 2006

Res-Kem and GE Water & Process Technologies Co-Sponsor Seminar

Please join us for a FREE 1-day event we're sponsoring with GE Water & Process Technologies. You'll get all the details about how GE is helping water conditioning dealers TURN WATER INTO GOLD!


Demonstration and training with GE Professional Series components including Autotrol, Magnum, and the NEW Stainless Steel 150 Valves.

GE Pros will address technical topics and field all your questions.

Learn about the benefits of being a GE Platinum Dealer Network Member!

Learn how Res-Kem can help you be an even bigger success!


All attendees earn two hours WQA (CPD) Credit.

DATE: Thursday, January 25, 2007
TIME: 7:20 am - 4:30 pm

Ramada Inn Philadelphia International Airport
76 Industrial Hwy.
Essington, PA 19029
(610) 521-9600

RSVP: Linda Shipley - 800-323-1983 or

Wednesday, December 27, 2006

Whole House RO System for Brackish/Salt Water

Here are some pictures of an interesting project our team out of our Jacksonville, Florida warehouse and assembly facility recently configured for a well driller customer. The system was designed to treat brackish/salt water from an ocean front property. As you can see, given the complexity of the water problem and limited space, the equipment was squeezed into a small space.

Whole House RO Control Panel

System Description:
This house is right on the ocean, pulling salt water in from a well. The house is very close to Marineland, Florida (The home of Flipper!) .

As expected, the well has a high Total Dissolved Solids, TDS, value. Also, the water had a "rotten egg", Hydrogen Sulfide, H2S, smell.

The equipment is as follows:

  • Well pump and tank
  • Hydrogen Peroxide injection system with Stenner PCM 5 controller and Hayes meter to correct the Hydrogen Sulfide, H2S, in the incoming brine/salt water
  • Whole house carbon filter with backwash system
  • Twin tank Fleck 9100 softener system for continuous treated water even during regeneration
    Well Tank, Whole House Carbon, and Twin Tank Softener
  • 10 micron prefilter
  • Whole house RO system rated for 1800 GPD
  • 500 gallon atmospheric storage with level switches for pump protection

  • Atmospheric Storage Tank
  • Repressurization pump and tank for house feed water
  • Fleck 5600 backwash polishing filter for pH and taste control
  • Hydrosafe 12 gpm UV Light with stainless steel housing for bacteria control activated with flow switch.

  • References:

    DT Series Softener Brochure
    DT Series Softener Engineering Drawing

    Problems with a Bruner(R) Softener Multi-Port Valve

    Here are some common problems we see with very old Bruner(R), Bruner-matic(R), and Culligan(R) Hi-Flo (TM) multi-port valves. A recent request for help prompted this posting.

    I have an old Bruner softener with a large cast iron multi-port valve. Here are some of the issues:
  • Periodically my brine tank overflows
  • My runs seem to be shorter than before
  • I seem to be using more salt than before
  • I replaced the softener resin only two years ago

    What could be the problem?

    Possible Causes:
    The Bruner Bruner-matic and Culligan Hi-Flo multi-port valves are very rugged valves that last for many, many years. Since they are so robust, people tend to forget they need to maintain the valves. The problems described above indicate there may be a problem with the multiport valve. The possible causes are:
  • Ruptured valve diaphragm
  • Leaky valve diaphragm
  • Bad brine valve
  • Blocked drain line flow control
  • Clogged pilot feed line or pilot screen

    Here is how to diagnose what the problem might be.

    Diaphragm Related Problems: Unfortunately, in order to figure out if a valve diaphragm is leaking or ruptured, you need to take the valve apart. Doing so will typically damage the diaphragms. Therefore, you should order a valve replacement kit before disassembling the valve

    Brine Valve Related Problems: In order to determine if there a problem related to the brine system, disconnect the brine line from the valve while the valve is in the "Brine Draw" step of the regeneration cycle.
  • If there is a vacuum, the Bruner multi-port valve is okay, but the brine valve is clogged or has failed.
  • If there is no vacuum from the multiport valve, check the drain line flow control for blockage. This is most likely the problem.

    Pilot Line Related Problems: Check and clean the pilot line strainer. The small screen on the strainer often gets clogged with valve corrosion chips.

  • Possible Remedies:

  • Establish a Preventative Maintenance, PM, program for the multiport valves

  • Replace old valves with a replacement valvenest using valves like the GE(R) Aquamatic(R) type.

  • Friday, December 15, 2006

    Purifying Bio-Diesel After Transesterification

    Given the current and projected world-wide energy demands, I have been seeing more literature, newsletter, and journal references to biomass derived energy sources to reduce demand for petroleum-based fuels and be better for the environment. One area of development is the production of biodiesel, but it has a serious downside. As a major ion exchange supplier, we are seeing substantial developments in the purification of biodiesel using specialized ion exchange resins.

    Chemical Process:
    The process to manufacture biodiesel requires transesterification of a vegetable based oil in the presence of a catalyst and methanol. What results are raw biodiesel (methyl ester), soap, catalyst, glycerol, and methanol. This raw biodiesel needs to be purified to applicable standards, EN14214 or ASTM D6751.

    The typical purification process uses as many as 8 successive water washings of the raw biodiesel. This transfers water soluble impurities soap, catalyst, glycerol, methanol, and some biodiesel to the water. This results in a huge amount of organic and catalyst contaminated wastewater. So for every gallon of biodiesel produced, you end up with 8 gallons of liquid waste. Not a very environmentally friendly byproduct of biodiesel production.

    A very elegant solution is available and being used extensively in Europe, a leader in biodiesel production. The raw biodiesel or once washed raw biodiesel is flowed through a tank of a special ion exchange resin. The resin readily removes the glycerol, soap, and catalyst, all corrosive to diesel engine components, and water from the raw biodiesel. It can take the glycerin from 500 ppm down to less than 10 ppm. This is significantly below the standard of 200 ppm. This potentially allows for higher concentration of biodiesel in blends with petroleum diesel.

    From literature and papers published by several ion exchange manufacturers, depending upon the process, 1 lb of ion exchange resin can treat 900 - 2000 lbs of biodiesel. Work is being done to have a way to regenerate the resin to allow for reuse.

    Thursday, December 14, 2006

    How Does a Softener Valve Nest Work?

    The "valvenest" for a water softener is made of a minimum of six valves. The easiest way to understand how the water and brine flows through the valvenest is to see this picture.

    The top flange attaches to the upper side port of the softener tank. This in turn connects to the top distributor. The bottom flange of the valvenest attaches to the lower side port of the tank. This is connected internally to the hub and lateral bottom distributor.

    The regeneration cycle is as follows:
  • Isolation from Service
  • Backwash
  • Brine Draw and Slow Rinse
  • Fast Rinse
  • Return to Service
  • Tuesday, December 12, 2006

    Dual Tank "DT" Softener Product Line Revamped

    The Res-Kem Dual Tank, "DT", water softener product line has been revamped yielding a complete line of standard products that can treat flow rates between 4 and 42 gpm continuously, with peaks rates up to 50 gpm. The capacity range is 15,000 to 270,000 grains between regenerations. These automated units are designed to provide continuous soft water 24 hours per day. Perfect for boiler treatment applications. By standardizing the product line, most systems are available for immediate pricing and shipment from inventory**.

    A new brochure has been completed and an engineering outline drawing is available.

    The DT-Series dual tank softeners are designed based around the Pentair Fleck 9000, Fleck 9001, Fleck 9100, Fleck 9101, and Fleck 9500 valves. The 9000, 9001, or 9500 Series Econominder feature an all brass control valve. With a meter initiated, twin tank alternating design, one tank is in service while the second is held in stand-by. These rugged control valves provide a low maintenance, high flow rate, and quality system able to meet the most demanding needs. A lower cost option is a Res-Kem DT Softener that incorporates the 9100 or 9101 Series non-metallic valves. Depending upon the valve, the meter that initiates the regeneration cycle is either of brass or composite construction.

    ** The "ET", electronic timer, for the Fleck 9000, 9001, and 9500 valves are a stocked item. The only exceptions are systems with the Fleck 9100 and 9101 valves. The optional "ET", electronic timer, is an non-stocked item.

    Friday, November 17, 2006

    Duties on Activated Carbon from the People's Republic of China

    Effective on October 11, 2006, duties on steam activated carbon from the People's Republic of China will have duties imposed between 13.78% to 228.11%.

    What does this mean?
    Res-Kem has been visited and/or notified by our suppliers that all activated carbon prices are increasing to a greater or lesser degree.

    How can Res-Kem help?
    Res-Kem has anticipated that this may occur. Through our buying power and our good working relationships with our key activated carbon vendors, we have options to help reduce the impact of the price increases.

    What happened?
    On October 4, 2006, David Spooner, Assistant Secretary for Import Administration at the US Department of Commerce, USDOC, issued a "Preliminary Determination of Sales at Less Than Fair Value and Postponement of Final Determination: Certain Activated Carbon From the People's Republic of China". Click here for the full text of the release.

    Why did this happen?
    On March 8, 2006, the USDOC, received a petition on imports of certain activated carbon from the PRC from Calgon Carbon Corporation and Norit Americas Inc because they felt the products were being sold at "Less Than Fair Value" a.k.a. "Dumped". This investigation was initiated on March 28, 2006.

    USDOC Summary of Determination
    "SUMMARY: We preliminarily determine that certain activated carbon from the People's Republic of China ("PRC'') is being, or is likely to be, sold in the United States at less than fair value ("LTFV''), as provided in section 733 of the Tariff Act of 1930, as amended ("the Act''). The estimated margins of sales at LTFV are shown in the "Preliminary Determination'' section of this notice."

    What's Next?
    The USDOC will make a final determination early next year.

    Monday, November 06, 2006

    Res-Kem Re-Certified by Commonwealth of Pennsylvania

    On October 23, 2006, the Department of General Services, of the Commonwealth of Pennsylvania, re-certified Res-Kem Corp as a Woman Business Enterprise.

    Tuesday, October 31, 2006

    NASA Water Treatment System and Oxygen Generation

    There are many difficult water treatment problems we all deal with on a daily basis. Few are life and death like this application.

    I am on a wide variety of email newsletters. Here was an interesting article on how scientists at NASA's Marshall Space Flight Center (MSFC) are working on taking all available sources of water in a space craft or space station and reclaiming them for reuse. This includes humidity and urine! Overall they achieve 93% recovery of the water.

    The name of the project is Environmental Control and Life Support Systems, ECLSS, and is pronounced "EE-cliss".

    What is also interesting is they are using part of the water to generate oxygen by electrolysis. In this way, long term mission on the Moon or to Mars can be feasible. In order for this to happen, they need to increase the recovery closer to 100%

    Thursday, October 26, 2006

    New Calcium Carbonate Brochure From Imerys

    Imerys Performance Minerals of Roswell, Georgia just released its first brochure for its extensive line of NSF-certified calcium carbonate media for:
    - pH adjustment
    - Corrosion control
    - Remineralization of desalinated water

    Many forms of calcite media are available, but not all are safe for use in drinking water. The Imerys media has been tested and certified by the NSF International to NSF/ANSI Standard 60. There are five different NSF-certified grades of calcium carbonate media:
    - 40-200(TM) NSF sourced from Marble Hill, Georgia and Sylacauga, Alabama
    - 30-50(TM) NSF sourced from Marble Hill, Georgia
    - XO White(TM) NSF sourced from Marble Hill, Georgia
    - Z White(TM) NSF sourced from Marble Hill, Georgia
    - OZ White(TM) NSF sourced from Marble Hill, Georgia

    Res-Kem Corp stocks XO White NSF and Z White NSF for immediate shipment. We can provide the other media grades upon request.

    Friday, October 20, 2006

    Res-Kem Re-Certified by the WBENC

    At the request of many customers, Res-Kem has a yearly audit to insure that we continue to meet the requirements of The Women's Business Enterprise National Council (WBENC). The WBENC is the largest, independent, third-party certifier of businesses owned and operated by women in the United States. We are proud to inform our customers that Res-Kem has been re-certified for 2007 as a WBENC-Certified woman-owned business and a leader in residential, commercial, municipal and industrial water treatment systems.

    Most importantly, customers do business with Res-Kem because we are great at what we do, providing the highest quality water treatment equipment, filter media, ion exchange resins, replacement parts, equipment service and Service DI, not merely because we are woman-owned. With that said, there are many corporations of various sizes that have internal targets designed to increase opportunities for women-owned businesses to work with them. We can help you meet these targets.

    Monday, October 09, 2006

    Dow Introduces Two New Dowex Marathon Ion Exchange Resins

    In some industry news, The Dow Chemical Company told us two new products were added to Demineralization price list. These ion exchange resins are Dowex Marathon 650C (H) and Dowex Marathon 550A (OH). These resins are used for polishing mixed beds that do not require nuclear-grade specifications, and where good color differential and excellent separation are required.

    Dowex and Marathon are trademarks of The Dow Chemical Corporation

    Wednesday, September 20, 2006

    Can you analyze ion exchange resin and what do you require?

    The short answer is YES. We analyze ion exchange resin and the procedure is simple!

    Background Information:
    The redesigned Res-Kem web site is a great resource for water treatment products and services. We have made every attempt to make the site easy to navigate. Since there is so much information on, periodically I will highlight products and services that may need additional exposure.

    One of the services I would like to highlight is our resin analysis service. Your resin sample is analyzed for its:
    - Chemical properties - the capacity of the resin to remove ions
    - Physical properties - the percentage of whole, cracked, and broken resin beads
    - Mix - the percentage of cation resin and anion resin
    - Regeneration Efficiency (if applicable)
    - Organic Fouling (if applicable)

    You will need to take a representative sample of the resin in your vessels. This is very simple process if your equipment has been properly designed. Simply remove the manway or top mount valve from the tank. Drive a semi-rigid tube or pipe into the bed and educt or vacuum with a small clean shop type vacuum. A one-quart sample is ideal for resin analysis.

    Prior to shipping your resin sample, contact Res-Kem at 800-323-1983 or 610-358-0717 so we are prepared to handle your resin sample.

    We will need a purchase order and copy of the Resin Analysis Submittal Form faxed to us at 610-358-4642 OR e-mailed to The samples must have a copy of that fax or email document attached on the outside of the box. A minimum 3 oz. sample is required of INDIVIDUAL RESINS and 8 oz. for MIXED RESINS, but a quart is preferred.

    The cost of the services is detailed in this price list.

    Monday, September 11, 2006

    My backwash flow rate is too high for my well and well pump

    A common design issue for sand filters, multi-media filters, greensand filters, arsenic removal units, etc. is the large difference between the backwash flow rate and the flow rate during normal operation. Depending upon the media used, the backwash flow rate can be 2X to 10X the service rate. Due to restrictions in the piping coming to the unit or the well feeding the plant, the unit cannot get an adequate backwash flow rate. Most water supplies are not designed to handle such a wide swing in flow rate and the drain line will have to be appropriately up-sized. In particular, a plant well water source can not be cost effectively sized for such a large flow difference.

    To address this predicament, Res-Kem has been selling triplex sand filters, multi-media filters, greensand filters, arsenic removal units, etc. to reduce the backwash flow rate. The tradeoff is the cost of the extra valves and tanks with a backwash flow rate that is reduced by 50% for a continuous system and 67% for a non-continuous system.

    Depending upon the size of the units, all of them can be skid mounted. This makes for a very simple field installation with a single electrical connection. Also, the skid will have a single feed, product, and drain connection.

    An optional feature of a triplex skid is that a separate line for an alternate backwash source can be added. This allows for the use of a "clean" water source to backwash the units. If water storage is not available, two units can be used to backwash the third.

    Thursday, September 07, 2006

    Why should I treat my boiler condensate?

    A question that we receive frequently from visits to customers and potential customers is "Why should I treat my boiler condensate?"
    Our Answer:
    The reason why to treat your boiler condensate is condensate systems always leak. Heat exchangers are where most of the leakage problems start. Tube sheet and tube leaks, of shell and tube heat exchangers, are the typical cause. This is where untreated cooling water can contaminate the process water leading to corrosion. Every system must have a method to handle this leakage.

    When a condensate system is not properly controlled or simply ignored, corrosion takes place. Iron, copper, and other harmful contaminants are washed back into the boiler systems. This wastes energy because these contaminants reduce heat transfer. Depending upon the type of contaminant, a layer of 1/32" can waste between 2% and 7% of the fuel used in the boiler. Wasted Fuel Graph

    A simple solution is to blow down the boiler to improve water quality, but this wastes heat, requires more makeup water, and increases boiler water chemical usage.

    The cost effective solution is to "polish" your contaminated condensate for reuse. As more condensate is reused, less make up water is required, reducing both chemical consumption and energy requirements.

    Res-Kem Sodium Cycle Condensate Polishers are available in a wide range of self-contained packages configured in single, double, and triple unit arrangements to treat condensate return for reuse as boiler feedwater. The standard wetted parts for Res-Kem Condensate Polishers are stainless steel. Single units are rated for flows up to 710 gpm. For larger flow rates, contact Res-Kem to determine whether larger or multiple units would be best choice.

    Contact Res-Kem to work up the energy savings available by polishing your dirty condensate. The payback is both swift and dramatic.Res-Kem Condensate Polisher specification sheet

    Friday, August 04, 2006

    Why do you not recommend using galvanized pipe on your water softeners?

    A question often asked is materials of construction for water softeners. Summarized below, Res-Kem's Director of Engineering, Bob Hader answers in a recent "Engineering Notes":

    "Corrosion can occur with any type of piping depending on the application, environment and precautions taken to prevent corrosion. We at Res-Kem find that steel piping with iron fittings offers the best balance of corrosion resistance and cost.

    First, softened water has not shown to cause any more internal corrosion in steel or galvanized piping than hard water. Corrosion, which does occur with unlined steel tanks, piping & fittings or galvanized tanks pipe & fittings is generally caused by other factors. Some of these are pH, temperature, dissolved gasses (oxygen and carbon dioxide) in the water, contact with air and galvanic action.

    The greatest contributor to corrosion we see with water treatment equipment is on the exterior surface of tanks, pipe and fittings. Given most water treatment is in areas where the air is warm (boiler rooms, laundries, non-air conditioned utility rooms) and the water is cold; condensation forms on everything. Uncoated or unprotected steel tanks, steel piping and cast iron valves will rust and corrode. Galvanized piping is not free from this problem. The corrosion will take place at the threads (which are not galvanized)."

    Here is the complete Engineering Note.

    What is an Empty Bed Contact Time (EBCT)?

    We receive many questions on calculating the Empty Bed Contact Time as follows: "How do I calculate the "Empty Bed Contact Time" for sizing my carbon bed?"

    Our Answer:
    Calculating the Empty Bed Contact Time, EBCT, is fairly easy to do once you know that the EBCT has the units of time, and usually presented in minutes. You need to know the volume of the carbon bed in your vessel and the flow rate. Just watch to be certain your units are consistent.

    For the units commonly used in the United States:
    V = Carbon Bed Volume (cubic feet)
    Q = Flow Rate (gpm)
    C = Conversion Factor (7.48 gallons/cubic foot)

    EBCT= (V x C )/ Q

    The EBCT for some common contaminants are:

    Chlorine = 2 minutes
    VOC's = 7 minutes
    Hydrogen Sulfide = 4 minutes

    Wednesday, June 14, 2006

    Am I Using Too Much Water During My DI Regenerations?

    We received a question on the amount of regeneration water an operator is using:
    "Is it ok to use about 250 cubic meters of water for regenerating double-bed demineralizer system with a 125 gpm system capacity (132 cu.ft. cation volume and 55 cu.ft. anion volume)?"

    Our Answer:
    "250 cubic meters of water is about 66,000 gallons. Assuming you use around 20 gal/cu ft for backwash, 30 gal/cu ft for slow rinse, and 45 gal/cu ft for fast rinse; you are only using around 17,400 gallons of water total, not including dilution water for acid and caustic. Even if you round it up to 20,000 gallons, that is a long way from 66,000 gallons. You are using over three times the typical amount of water. You should work with your resin supplier to test the capacity of the resin and detect any possible foulants. You may have to clean or replace the resin."

    Bacteria in RO System

    We received the following question on our web site:
    "I am getting some bacteria coming out of my RO that I was not getting before. How can I clean the membranes."

    Our Answer:
    "You can use a product known as Minncare(R) or Oxonia. Both are sanitizing agents made up of hydrogen peroxide and peracetic acid. Dilute to 50 - 100 ppm, pump through RO, soak for an hour and rinse out. Please check with you membrane supplier and Minntech/Oxonia to insure compatibility with your RO membranes. Both Minncare and Oxonia are on the web."

    Thursday, June 08, 2006

    "Take my CARBON ... PLEASE!"


    Almost since our founding in 1983, Res-Kem's Technical Services Group has removed (rebedded) spent media, ion exchange resin and activated carbon, from industrial water treatment systems. Part of the rebed service usually includes removal of the spent media from the customer's site. Companies who regularly deal with waste know that getting rid of spent ion exchange resin or activated carbon can be a fairly complicated process. We take this hassle away from our customers.

    For years, Res-Kem sales people have known our residential and commercial water treatment dealers have the same problem - how to properly dispose of spent activated carbon that accumulates over time. Res-Kem and Calgon Carbon have teamed up to help our water treatment dealers with spent activated carbon return. As a service to our dealers, Res-Kem will accept spent carbon at the Aston, PA facility. Call for pricing. Click here to download the PDF of the fine print.

    Sunday, April 30, 2006

    Launching new Res-Kem website and Res-Kem blog!

    The new Res-Kem website is now live!

    And with it - the new Res-Kem blog, where we will talk about many topics of interest to the water treatment community, projects for some of our customers, and trends in the industry.