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ppm of Chemical dosing 7

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Nad87

Chemical
Mar 26, 2020
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Dear all,
In water treatment plant there are many chemicals used and as I know there is a concentration of each chemical recommended from the supplier according to raw water analysis.
Please anyone can explain me how they recommend the concentration of chemicals or anyone know the relation between the raw water analysis result and the concentration of chemical (ppm) to be recommended?
Thanks in advance
 
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There is no way, chemicals are based on analysis, your water treatment supplier will tell you the ppm to inject as result of previous analysis done. Meanwhile try google, Baker Hughes, Nalco, Dow Chemicals and others.

luis
 
I think a good vendor would be willing to explain how they make recommendations on what chemicals to use and how much. They may not share their data or tools with you, but I'd think they get people calling them with this question often. If I was responsible for wastewater treatment at a site, I'd want to know why we're buying what we're buying and I'd think the vendor is going to be critical to that answer.
 
0707 jari001 Thanks a lot
MJCronin thanks anyway but just take it easy bro here it is a forum if any one know a simple information which can help just share with others without too much philosophy it is as simple as that only there is a recommendation for each chemical for example antiscalant from x ppm up to y ppm HCl from x ppm to y ppm ... if any one has experience he can share with us why complicating things!!
 
Yes, I completely agree with my best "bro"..... "Nads" .... I will take it easy

If anyone out there can summarize the rules of water chemistry in one or two sentences , Please share them with us !!! .... Give us "rules of thumb" that will work in all circumstances !!!

We should all respect your seminal statement; "Why complicating things !!!"

There is certainly no sense in wasting time purchasing books, studying any chemistry or engineering texts when every area of science can be boiled down to two or three "rules of thumb" ...... "bro"

MJCronin
Sr. Process Engineer
 
That's a tough question Nad87. Folk are trying to help you so it would be helpful in return if you were more specific and less philosophical.

MJCronin is bang on with all his answers. Take the advice, be grateful, and come back with specific questions.
pierreick, too, the old Betz handbook,essentially now online at the site he gave, is another great place to start.
These could be the two best books to study first, on your way to becoming knowledgeable in water treatment.

Many specialty chemical vendor reps may often not know exactly why the doses are what they are, either. They often read it from their in-house training guides and literature, or on on advice from an in-house specialist, or hear this, from reading their handbooks (the two main ones are cited above).

As one wise poster here has often said, "There's nothing like cracking open a book". You go Nad, try it : -).

Good luck

PS: Yes, a forum on water process chemistry would be nice.
//
 
Nad87,

You already essentially posted this question TWICE before now.

Here:

and here:

Each time, your question has been overly broad, and the responses were appropriate. If you have more specific questions regarding dosing (E.G. How do I dose acid/base based on incoming stream pH for RO system pretreatment? would be the MINIMUM specificity required for us to be able to handle any kind of response), then ask. Answers to your questions will be as specific as your questions allow.

Otherwise, STOP POSTING REPEAT THREADS!!!
 
Despite what the previous posters have suggested, you have posted a simple question. Most of the time, the chemical supplier is working from experience.

For water clarification, the chemical supplier will do what is called a jar test.

Jar Test Apparatus

There are typically 5 jars or so for the test. The person doing the test is aware of the typical dosage for the water treatment application. Based on the typical dosage, the person adds slightly more chemical and slightly less chemical than the typical dosage to arrive at the optimum dosage.

Visual inspection of the jars allows one to visually determine the optimum dosage.

If you are treating a surface water that changes with the season, you may have to do the test daily.
 
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