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Icon_missing_medium Gary Schreib... 0 Posts
10/08/2010

WTO Board / Softener Slow Rinse Time

I, as an employee of a resin manufacturer, will be happy to share Elution Study protocols. To detailed to put here. Just send me an email requesting the info and I will email it to you. Chris' posting is a "one shoe fits all" idea. I suppose if one chooses those flow rates then have it. Otherwise do an elution study and eliminate call backs because the water is either not soft or taste's salty.
 
Icon_missing_medium chrishughes 0 Posts
10/08/2010

WTO Board / Softener Slow Rinse Time

I checked with the resin manufacturer. I was told:
"Slow rinse is 1.2 bed volumes of water at same flow as dilute brine. 1 bed volume equals 7.49 gallons per cubic foot so 1.2 BV for a 1 cf system is 9 gallons. Divide this by flow rate and this gives time. The 1.2 BV is designed to move the 10% brine plug through the bed allowing all the resin to have the same contact time before the fast rinse begins. If you determine the 10% brine moves through the FM bed slower or faster then the amount of slow rinse should be adjusted accordingly."
 
Icon_missing_thumb Anonymous
10/08/2010

WTO Board / Softener Slow Rinse Time

There are several information sources available for elution study info.Take your pick.Type in water softener elution study into an engine and choose the one that is the most understandable to you.
It would be of interest to find out how many of us actually use elution as a regular form of service.

Gary L. Lindsey
CWS VI CI
 
Icon_missing_medium Taoward Lee 10 Posts
10/08/2010

WTO Board / Removal of Cu and Zn

The weak acid resin is only reliable if the pH is consistently above 4. Acid surges will convert the resin to the hydrogen form and cause the possibility of zinc or copper spikes. The WAC resin in the hydrogen will not pick up the copper and zinc without converting it to the Na form.

High TDS with high sodium will interfere will zinc and cooper removal using a SAC in Na form.


 
Icon_missing_medium Jim Wark 8 Posts
10/07/2010

WTO Board / Softener Slow Rinse Time

Sorry for the ugly typo.....Many of us here....simpletons like me and my typing !!!
 
Icon_missing_medium Jim Wark 8 Posts
10/07/2010

WTO Board / Softener Slow Rinse Time

Gary, elution study time is the correct way but many of usher do not understand how to do it. Could you shed a little light on the subject for us? THANKS
 
Icon_missing_medium Gary Schreib... 0 Posts
10/07/2010

WTO Board / Softener Slow Rinse Time

The best way to do that is to start the softener regeneration and then during slow rinse do a Brine Elution study to determine the time needed to set for slow rinse. Failing taking the time to do that you can use the recommendations shown on any resin manufacturer's Engineering Bulletin and choose the flow rate and number of bed volumes within the range shown and "hope" you have chosen correctly. You cannot beat the Elution Study way.
 
Icon_missing_medium chriskofer 0 Posts
10/07/2010

WTO Board / A universal RO membrane?

Thank you.
 
Laurence%201998 Laurence DAl... 2 Posts
10/06/2010

WTO Board / FDA Certification

How do I get a copy of the Watercheck with Pesticides test by NTL?
 
Icon_missing_thumb Anonymous
10/06/2010

WTO Board / A universal RO membrane?

I have in the past installed 50 GPD membranes without changing the concentrate restriction.As long as the original membrane production was close.For instance 36 GPD.Most of the applications were on municipal water supply.Ultimately 3.5 to1 or4 to 1 for residential use should be the drain to product ratio.If the ratio drops you run the risk of problem with fouling the membrane particularly using private well supply. There are numerous charts available online to give in milliliter the flow amounts.It might be a good idea to pick up a milliliter graduate at a lab supply for this purpose.If you continue to load up membranes you might try installing a bypass around the drain.In other words install a tee in the tubing before the drain fitting. Install a 1/4" ball valve on the line from that tee to drain.You can then periodically open that ball valve and move water at a higher rate along the membrane surface and dislodge build up. Of course if the restrictor happens to be an insert type you'll have to replace it with an inline type. There are certainly other issues you might want to look into to include the type of prefiltration you're using both directly associated with the RO and upstream.


Gary L. Lindsey
CWS VI CI
 
Icon_missing_medium richardchase 0 Posts
10/06/2010

WTO Board / Softener Slow Rinse Time

You should check with the resin manufactures technical data specs on the grade your using. Typically on cation resin you will need three bed volumes for slow rinse and four bed volumes for fast rinse.

 
Icon_missing_medium chriskofer 0 Posts
10/06/2010

WTO Board / Filox system no longer working

We do well using IX for manganese-even in soft water.

You need to be thoughtful of what happens to the waste water if you backwash filters frequently. If it's going to a septic system, you may be increasing the load on that two- or three- fold.
 
Icon_missing_medium chriskofer 0 Posts
10/06/2010

WTO Board / A universal RO membrane?

I suspect fouling may be an issue if the velocity is too low. The value of certification is a whole other discussion.
 
Icon_missing_medium davidcarlile 0 Posts
10/06/2010

WTO Board / A universal RO membrane?

Maybe a better analogy would be: change from a 4 cylinder engine to an 8 cylinder and NOT changing the transmission and differential.
Okay - back to water speak: for proper RO operation, check with the RO membrane manufacturer for their recommended Product to Reject ratio. Typically this is 1:3 or similar. To just change the membrane to a 50 GPD will subject you and your clients to possible membrane fouling, shortened membrane life, and reduced % rejection performance.
Solution: pick a membrane AND matching flow control and change both when the service indicates membrane change is necessary.
PS: if the unit is NSF certified, you may want to consider using only the original OEM components to properly maintain the NSF status.
 
Icon_missing_medium mariannemetzger 0 Posts
10/06/2010

WTO Board / FDA Certification

Chlorine is considered a pesticides by the EPA as it is used to kill microorganisms.
Marianne Metzger
National Testing Laboratories
 
Icon_missing_medium chrishughes 0 Posts
10/06/2010

WTO Board / Softener Slow Rinse Time

How does one establish the slow rinse time of the regeneration cycle? If it matters this is for upflow brining of a packed resin bed.
Thanks
 
Icon_missing_medium chriskofer 0 Posts
10/06/2010

WTO Board / A universal RO membrane?

I was hoping for a more technical reason....
 
Icon_missing_medium richardchase 0 Posts
10/05/2010

WTO Board / A universal RO membrane?

Not a smart idea. That’s like changing the sparkplug on your lawnmower and not properly gaping it.

 
Icon_missing_medium chriskofer 0 Posts
10/05/2010

WTO Board / A universal RO membrane?

I have been more requests to service undersink ROs installed by others-generally fairly generic units. Most of them are installed on unchlorinated well water.

My question: would I be safe by installing 50 gpd tfc membranes without changing the flow control?
 
Icon_missing_medium christopherd... 0 Posts
10/04/2010

WTO Board / Ultra Filtration

The ElectroCoagulation process uses electricity and metal blades to make tannins separable from the water without the aid of additional chemicals. Therefore, there are no hazardous waste disposal costs. Lime softening would require bring in truck loads of lime, hauling away truck loads of precipitated lime sludge, several full time operators, and continues operation. EC is much simpler and less expensive to operate. With our EC units power requirements are low, they can handle high volume, and they can turn off and on by demand using a float switch. A simple flotation barrier installed in the existing pond will clarify the water before discharge. The coagulated solids will remain in the pond. An atmospheric clarifier could be use to separate the solids from the coagulated water if you want collect the solids for continual disposal.

We just installed a 1,000-gpm EC + UF system as pretreatment to RO. ElectroCoagulation is very effective eliminating the problems associated with contaminants being too small to be stopped by the UF.

 
Laurence%201998 Laurence DAl... 2 Posts
10/04/2010

WTO Board / FDA Certification

Don't understand your meaning. Chlorine is not a pesticide. If PAC comes in contact with food and beverages, doesn't it have to be FDA Certified?
 
Icon_missing_medium christopherd... 0 Posts
10/04/2010

WTO Board / BIG RO ?

We just completed a 1,000-gpm municipal project this year with different but similar problems. Perhaps it would be helpful to you. Here’s a sketch of the details.

We used a train consisting of ElectroCoagulation followed by ultra filtration and a vacuum clarifier prior to reverse osmosis.

The application we created the system for was a cooling tower. The water contains about 50 ppm of silica. The water is evaporated 2.5 cycles in the cooling tower before the silica builds up to limit the water usage. The blow down from the cooling tower is 40% of the incoming water from the sewer plant.

The blow down from the cooling tower goes to an evaporation pond and then to irrigation. The high way is expanding into there irrigation space, and they were concerned that the high TDS level water might percolate through the ground into the ground water.

This establishment was also adding additional electrical generators which will generate additional cooling tower blow down.

They decided to move to a zero discharge from there facility.

With our system the water evaporated in the cooling tower is increased to 90% because the silica is removed by the EC UF VC process. The silica level was reduced from 218 ppm to well under10 ppm. Because the silica is removed from the water, the TDS level in the cooling tower can be increased from 4,000 ppm TDS to 10,000 ppm TDS.

The RO unit will separate water for boiler feed, and 70.000 ppm TDS reject water.

The 70,000 ppm TDS reject water will then be place in the existing evaporation pond.

The advantage of the EC VC UF system is beneficial. Traditionally a UF rejects 10% of the flow for disposal. This plants’ UF is designed for 725 gpm permeate, and 80 gpm reject.

In this case the coagulated solids are separated from the water in the vacuum clarifier. The separated solids will go to the dumpster, and the clear water will go back to the UF unit. There is no evaporation ponds required with this part of the system.

Because of the reduction of the silica and phosphate by the EC unit, the RO can concentrate the reject to 70,000 ppm TDS. 85% of the water will permeate the membrane and be used for boiler make up feed water. 15% of the water will be rejected from the membrane and goes to an evaporation pond – or in your case possibly to a distiller. The salt water will be very clean, free of silica, calcium, etc. as this is important with distillers and crystallizers. In the case with the project we did, the 725 gallon input will produce 109 gallons of reject containing the 70,000 ppm TDS.

A traditional method for silica separation is lime softening. Our system was a bit less in terms of capital costs and much, much less in terms of operational costs. The levelized cost of a ElectroCoagulation system is about one-fifth the levelized cost of a comparable lime softening system. This difference is realized by lower operating costs across the board.

Hope this helps.

 
Icon_missing_medium christopherd... 0 Posts
10/04/2010

WTO Board / Removal of Cu and Zn

Depending upon your flow rate, if it's large enough, Electrocoagulation might be right for your needs and may have some added side benefits. Our systems are exceptionally good with metals with copper and zinc >99+% removal rates You can check out our site at www.quantum-ionics.com
 
Icon_missing_medium mariannemetzger 0 Posts
10/04/2010

WTO Board / FDA Certification

The FDA does not certify any filtration equipment. It does require proof that filtration equipment and components meets the requirements for food grade materials. It's the EPA which requires a certification for pesticides such a chlorine.
Marianne Metzger
National Testing Laboratories, Ltd.
 
Laurence%201998 Laurence DAl... 2 Posts
10/03/2010

WTO Board / FDA Certification

We are interested in FDA Certification for wood based powdered activated carbon. Evidently most of the applications are in the food and beverage industries along with WTPs.