Water Treatment Questions Welcome!
I am fairly new to the forum. I have noticed there is very little here on the water treatment side and I hope I can be of some help. I am a water treater in Southern California, which has the worst water quality in the U.S. outside of Arizona.
If anyone has questions, please ask. I am a degreed chemist and I love to share knowledge and help any where I can!
good to have you onboard
the good ship lollipop
It`s better to be silent and thought the fool; than speak and remove all doubt.
What do you think of the Dolphin and others like it?
God Bless our Veterans
God Bless the USA
Iíve been following your replies here.
Welcome to the site and thanks for the input.
The Dolphin, well there is so much to say about it... and unfortunately nothing good. They say that the electromagetic pulse 'alters the crystalization' of the calcium molecule and makes a silt called argonite. No one can say specifically how it does this and that includes the Dolphin people.
Originally Posted by Randy S.
With out getting too muddled in the science, here is what you need to know. If you use this calculation on your make up water, you can determine the actual cycles of concentration, (tower conductivity divided by makeup conductivity = cycles) that you can run without chemical or any treatment and avoid scaling. The calculation is:
The square root of (11,000 divided by (makeup 'M' Alkalinity x makeup Ca Hardness)
For example, if your makeup has 90 parts of 'M' Alkalinity and 60 parts of calcium hardness the the equation would be:
Sq Rt of (11,000 divided by (90 x 60)) or the Sq Rt of 2.037 which is: 1.43 cycles. Therefore, if citywater conductivity is 500, then the bleed setpoint on the tower would be 500 X 1.43 or 715 umhos.
Here is the point I am making, on any Dolphin system you encounter that is not scaling, run this calculation on the makeup water and you will find that the system is running at the maximum cycles it can without chemical, meaning the Dolphin is doing nothing.
Now let's talk Green Technology. If on a chemical program, I can run a tower at say 5 cycles, and on the Dolphin I can run 1.5, then which is truly "Green"? Here's food for thought-
If you have a 1000 tons of cooling that averages 80% load, 12 hours per day, at a 10 degree Delta T, then the evaporation rate would be 30 gpm or 21,600 gallons per day. That is fixed. However the bleed rate at 1.5 cycles is 60 gpm or 43,200 gallons per day. At FIVE cycles the bleed rate falls to 8 gpm, (yes that much) or 5,760 gallons per day. So by using chemicals, which are organic and non hazardous or harmful to the watersupply, you are saving almost 14,000,000 gallons of water per year. In California, that's HUGE! Now, at roughly $2.00 per thousand gallons of makeup, and $2.50 per thousand gallons of bleed, (sewer) that's $63,000 in real money that a facility would save by using good water chemistry. Now stop and think how much you would pay for that chemical program. A good rule of thumb is $1.00 per ton per month. So, that would be $12,000 worth of chemical and service for a year. That's a pretty big payback, verses the Dophin which costs, what $30,000 or so (I really don't know how much they cost).
That is the problem with the Dolphin, they sell a piece of equipment that does absolutely nothing except suck electricity and wastes water. Here are some links of studies done where the Dolphin has been used:
I hope I have been helpful. There are some chemical free devices that do work to remove calcium, but beware... calcium, in addtion to being a scale forming nuicance, also acts as a corrosion barrier on steel. If your water treater uses a good program, then there is nothing 'Greener' and more effective that a quality chemical treatment!
How do you feel about the use of reclaimed municipal sewer water in cooling towers?
I've made my case against it, but may be overridden by the politics of green.
God Bless our Veterans
God Bless the USA
Reclaimed water is an option and will work, however whatever water treatment company you decide to use really, really needs to know what they are doing. And I can tell you most of them will tell you "no problem", and then proceed to destroy your system. And with reclaimed water, that can happen VERY fast.
You have two concerns with reclaimed water. The first is Ammonia. All reclaimed water will be very high in NH4, (ammonia) and that is a tricky animal. Ammonia will attack and dissolve copper quickly. Dissolved copper will be in such high concentrations, that your tube sheets will begin to corrode and before you know it, the wrong side of your chiller will be filled with water.
The other concern is biological. The reclaimed water will be very, very high in sulfates. This will begin to feed a very common type of bacteria know as Sulfate Reducing Bacteria. They are the same guys that sit in your sink traps and smell like rotton eggs. The remove Oxygen from the SO4 (sulfate) ion which leaves free sulfer. The sulfer then looks for Hydrogen, creating Sulfide or H2S; H2S then oxydizes to H2SO4, which is Sulfuric Acid. Not bad by itself, except they create the acid underneath their own slime, creating under-deposit corrosion at the colony's site. Very hard to detect until failure.
Scaling will not be an issue because there will be a lot of Phosphate in the reclaimed water. As a matter of fact, if the water treater knows what he/she is doing, they will not treat your system for scale prevention, rather corrosion and biological prevention will be the focus. The chemicals they use must not have Phosphate or Phosphonate in them or you will essentially be adding bacteria food into the water.
Here is what I have done in the past-
At the very first part of the plant where the reclaimed line comes in, I would feed Azole. This will protect the makeup line from falling apart, as well as keep the copper from plating out further on in the system
Since Azole does not nuetralize ammonia, that would be my next step. What kills ammonia? Chlorine! So now, you have to feed another corrosive chemical to destroy an even more corrosive compound. In order to prevent chlorine overfeeding, I would install an Ammonia Analyzer and feed Chlorine based on free Ammonia. The chlorine is only being fed to counter act the ammonia, not necessarily as a biocide.
Now, since your using Chlorine, you have to keep the pH between 7 and 8 or the chlorine will not work. Chlorine is only effective at that pH range. So, you have to feed Sulfuric Acid. This is not optional. You cannot use reclaimed water without using pH control.
I said you dont need to treat for scale, and that's true but you do need to use a polymer to keep the resulting Calcium Phosphate in solution rather than turing into a sludge in the sump. So the chemical treatment would be a polymeric dispersant as well as addtional azole to keep the copper protected from the chlorine and resulting chloramine.
Lastly, you need to feed a non-oxydizing biocide. I would recommend Glutaraldeyde. It will keep bacteria under control however you will feed a lot of it. You may also try Chlorine Dioxide, but Glut is the best in this application.
One last note, you may end up wasting alot of water, since you are feeding a ton of Chlorine, the Chloride level will build up fast. If that is the case then no matter how much chemical you use, you will get massive corrosion. Salt destroys everything, so make sure your people know to test for NaCl.
Using reclaimed is a viable option, but be ready for your water treatment costs to triple as well as the amount of time your people spend testing and monitoring. You will need to run tests for NH4, NaCl, pH, and conductivity every shift and make adjustments accordingly.
I hope this helps.
glad to have you here ww!!!!!!!!
true knowledge exists in knowing that you know nothing.
Sorry, typo I meant NH3, not NH4.
And thanks again for the warm welcome guys!
The facility Iím at has 4 BAC towers. Currently we have a chemical company under contract for treatment, Maybe itís me but I donít trust that the job is being done properly.
Last month I began the process of shutting down one tower at a time for the winter. The cold deck was about 1Ē thick in algae and I swear there was something swimming in it. Iíve been to the OSHA web site along with several others and the more information I get the more confused it gets. At my last facility the sumps were clean with very little algae.
Where can I get simple basic information on tower treatment and maintenance? Donít worry several members, myself included will be picking your brain but my bosses want it documented.
Beleive it or not, one of the absolute best references on water treatment comes from your own government. Here is the Military Handbook on Industrial Water Treatment. It not only has all of the relevant info you need, it has all of the calculations, everything. I have uploaded it and the link is here:
This is a public domain document so there is no copyright issue. I know it is one of the best because my company was a consultant, along with Nalco and a few others, to the governemnt in putting it together! There is some irrelevant stuff on navy boilers, but everything you seek is there!
Anything your water guy tells you can be proved or disproved with this manual.
a local water treatment co went out of business and I got all their tools.
I do want to learn more about water treatment as I think it is part of my job.
what are the most basic tests I can take for cooling towers, chillers and boilers?
For example, I am starting up a boiler replacement we did last week, tomorrow!
what are the most basic of tests I can take?
true knowledge exists in knowing that you know nothing.
Originally Posted by supertek65
The most important tests:
Total Hardness of feedwater : no higher than 1 ppm (0 ppm is ideal)
Sulfite of Boiler: 30 - 60 ppm (in most cases)
Boiler 'M' Alkalinity
Boiler 'P' Alkalinity
Boiler OH Alkalinity: Must be between 200 ppm and 800 ppm. To calculate OH Alkalinity the formula id (2 X 'P' Alkalinity) minus 'M' Alkalinity
Boiler chemical, usually Phosphonate: 10 ppm to 13 ppm as PO4
Boiler pH: between 10.5 and 11.5
Boiler neutralized conductivity: depends on the results of the OH calculation as well as a few other factors, but usually around 3,000 or sometimes as high as 4500.