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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... 3 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... 3 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.
 
Laurence%201998 Laurence DAl... 3 Posts
10/01/2010

WTO Board / Removal of Cu and Zn

This is for an Effluent Treatment Plant. Pretreatment as follows:
Poly Aluminium Sulphate in coagulation tank
Poly-Electrolyte in flocculation tank
DAP for biological towers.
 
Icon_missing_medium charlesjennings 0 Posts
10/01/2010

WTO Board / Removal of Cu and Zn

It sounds like you have some type of treatment system in front of your resin columns. If so, I would recommend looking at a metal precipitant. We have been running studies at various muncipalities that have a dissolved copper limit of 3.1 ppb and dissolved zinc limit of 10 ppb. The results at 10 mg/l of the metal precipitant has been non detect and no reduction in resin performance. We also passed the quarterly toxicity test. By getting this type of removal, you can increase the life of the resin and minimize regeneration. You also get a fail-safe feature in your process. I recommend that you contact, Gail at sales@jenfitch.com to get more information
 
Icon_missing_medium Jim Wark 8 Posts
10/01/2010

WTO Board / FDA Certification

The only type of unit that I can think of would be one using bacteriocidal resins such as iodinated. These are FDA certified as (If I remember right) pesticidal products, since killing bacteria.
Another might have the ceramic type candles or sumps filled with this type of media for residual effectiveness?
Would like to hear more if there is truly more to this.........
 
Icon_missing_medium owenthorsen 0 Posts
10/01/2010

WTO Board / FDA Certification

Anyone heard of an FDA certification for a POU water cooler?
 
Icon_missing_medium paulsweeney 0 Posts
09/30/2010

WTO Board / Another GAC Question

While you are on the subject of GAC, I know the situation has never arisen so far for me, but would there be any occasion to use GAC to raise pH ?

It is understood that activated carbon is great for odour and colour removal, ie. a good gas sponge and of course used in tannin removal.

As CO2 adds greatly to lower pH, so to tannins being humic and fulvic organic acids, - by removing both of these, would there therefore be a notable rise in pH ?

Has anyone studied the effects of using carbon in raising pH ?

Obviously the usual calcite and magnesia media dosing does the trick, but these add parametric ions to the water, where as carbon would try to aim for the same end goal but in the process doing the opposite by removing parametric non-desirables.
 
Icon_missing_medium markwiddison 0 Posts
09/30/2010

WTO Board / looking for media for arsenic

I have a client who has used the alcan aasf50 with good results at a fraction of the cost of the other arsenic medias that are over priced with NO guarantees.
Thanks
 
Icon_missing_medium Mark Brotman 0 Posts
09/30/2010

WTO Board / looking for media for arsenic

You can contact an Alcan rep - try Bill Reid at bill.reid@riotinto.com
As far as experience goes, were you looking to treat arsenic, fluoride or something else?
 
Icon_missing_medium Gary Schreib... 0 Posts
09/30/2010

WTO Board / Removal of Cu and Zn

Yes, provided it is all dissolved in the water. You haven't given us enough info on the application nor on the rest of the water analysis.
 
Laurence%201998 Laurence DAl... 3 Posts
09/29/2010

WTO Board / Removal of Cu and Zn

The concentrations of Cu++ and Zn+ are 8 mg/L and 12 mg/L respectively. We would like to get that down to < 1 mg/L. Is this the correct concentration range to get a SAC H form resin to work?
 
Icon_missing_medium Gary Schreib... 0 Posts
09/29/2010

WTO Board / Removal of Cu and Zn

Na form of SAC resin will remove both, HOWEVER, salt regeneration will not remove the accumulation. H form is the better choice if you can accept the low pH result. An alternative would be a WAC resin that has been regenerated with acid and also with NaOH. That result would not have a serious pH change. If this is an industrial waste water that is to be treated for disposal then a Chelation resin is a good choice.
 
Icon_missing_medium rexjohnson 0 Posts
09/29/2010

WTO Board / Water turning brown

Ame
If you don't know your source water, how much, how little, and from which supply you are dead in the water.
Sir, you must know the particulars of the water being fed to each and every part of your treatment system.
Without this information you cannot possibly make any determination regarding treatment.
This is a problem without an answer due to a lack of information.
Cordially
Rex Johnson
 
Icon_missing_medium davehedger 0 Posts
09/29/2010

WTO Board / Water turning brown

It's hard to troubleshoot from long distance, but here are some thoughts. I'm concerned that "they" can't tell you which source is used, because the answer to your problem could lie with "them." Your stagnant loop idea has merrit. Do you, or others who have maintained the system, ever flush the pipes with a cleaner? You could submit a sample to be checked for oxalic acid. Oxalic acid is sometimes used as a flush to remove rust scale. If your stagnant loop got blocked in for a long period of time, with oxalic acd, it's probably leaking now. Your plan to monitor the water weekly is a great step in the right direction. Good luck.
 
Icon_missing_medium arnevestad 0 Posts
09/29/2010

WTO Board / Water turning brown

Thanks for your input to my posting. They cannot tell us which water source is used, but the boiler make up is from the same water supply line and the boiler water is good.
Because this is a very old facility with appox. a dozen buildings with a common boiler house/Chiller, we are wondering if it could come from a loop that has been out of service and all of a sudden been put back in service? You know old stagnant water with a smell.
We are now following up with weekly water testing and still looking for the source of the problem. pH is on a slow increase.
Have a great day, Arne
 
Laurence%201998 Laurence DAl... 3 Posts
09/29/2010

WTO Board / Removal of Cu and Zn

We have Cu and Zn in the low ppm concentration range. Is SAC H form resin something we should take a look at to remove Cu and Zn?
 
Icon_missing_medium davehedger 0 Posts
09/28/2010

WTO Board / Water turning brown

I'm curious about the two sources of water, "city water or well with high silica." Different sources can have markedly different properties. If the source water has historically been intermixed in a holding tank, those differences may have been mitigated. You didn't give analyses of the two source waters, and the explanation for your observation might well be found there. Are the source waters mixed as they enter your facility? Or are you sometimes running on straight city water, and other times on straight well water. Late summer is usually the worst time for water quality from a well, as aquifers dwindle and contaminants are concentrated. If I were a betting man, I'd bet that your latest round of tests reflect the straight well water at it's worst.
 
Icon_missing_medium owenthorsen 0 Posts
09/28/2010

WTO Board / WQA Financial Presenter

Anyone on here recall the name of the blonde woman who made financial and stock presentations at the last couple of WQA trade shows?
I want to see how her portfoilio reflects what is going on in the water technology industry.
 
Icon_missing_medium arnevestad 0 Posts
09/28/2010

WTO Board / Water turning brown

We have a problem with water in a large chilled system. The water has been stable and clean with normal data for over two years. Last winter they did some major mechanicel work in the piping, removing a large water holding tank etc.etc.. The testing of the water was normal up to end of July with this data: pH 8.5, Conductivity 326uS/cm, Iron 0.05 mg/l, Copper <0.05 mg/l, Sulfate 15.6 mg/l and Chloride 6.4 mg/l.
On September 21st the following data: pH 5.13, Conductivity 652uS/cm, Iron to high for our test instrument????, Copper 0.29 mg/l, Sulfate <5 mg/l and Chloride 1.1 mg/l.
Taking the water sample the water is still clear and clean to look at, but next morning the water is reddish brown and cloudy.
Iron bacteria? or something ells?
The raw water source is either city water or well with high Silica.
Arne Vestad, IWTNA