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:

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.

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:

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.

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.

Summary:
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.

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!

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.

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.


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.



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.


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!



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.

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.


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.

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.

Stainless Steel vs Lined Carbon Steel Vessels for Industrial Water Softeners

Recently we received the following question from a prospective customer:
Question:
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.

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.


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.


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.

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 regeneration....is 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