Could you please give the ...

Published June 20, 2018 17:45 by Sean Roop, Industrial and Engineering Consultants, LLC - Senior Water and Process Consultant

Could you please give the final influent numbers so we don’t have to do the calculations for all three streams. There will be additional questions I’m sure in order to provide you with the best solution that includes economics. From the limited amount of information and I see a very high COD I am unsure of a decimal point versus a comma, as well I.e. 300 versus 300K COD. You need a BOD to COD ratio to begin the process. It looks like from the onset you’re going to have to use some type of AOP in order to change the COD to biologically degradable BOD. This can be done a number of ways, but we need the calculation completed first. Thanks Sean Roop - BD Manager for USP Technologies. If AOP just not work then you’re going to have to use something like RO or ion exchange or activated carbon. All of these are very expensive! I will look forward to your response.

2 Comments

After rereading the initial data, the two recommendations for equalization and pH reduction are spot on. At pH of 11, you most certainly have stable emulsions. Lowering the pH will break out the oil. Be very careful not to drop the pH too low, or the potential for H2S evolution becomes much higher!

Published July 2, 2018 15:13 by Sean Roop, Industrial and Engineering Consultants, LLC - Senior Water and Process Consultant

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Sorry Sean Roop

it was due my mistake. I mean COD = 300,000 mg/l (three hundreds thousand milligram per liter) and BOD5 = 180,000. I have estimate according COD content (60% COD), don't have specific information. You have mentioned AOP solution. I never use before, i don't have any experience about AOP. Could you show me more information.

thanks

Published June 21, 2018 06:06 by Ho` Ha, WWTP supervisor at musimmas group

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1 Comment

There are many AOPs, but the reaction is the same in forming a free hydroxyl radical to break down otherwise recalcitrant COD. Used a lot for it’s simplicity is Fenton’s Reagent. You would do as much at the DAF as possible first. I completely agree with an Equalization Basin to control loading; both hydraulic and organic. I also agree with dropping the pH to get your best oil and grease breaks, then screening for the proper coagulant and flocculant. Side note that a small amount of ironin this water can be recharged (reoxidized) using hydrogen peroxide. This cuts down on your coagulant and flocculant to provide even a better DAF effluent. Now you would use Fenton’s. You add iron salt (ferric chloride for example), and then drop the pH of the cleaned up DAF effluent to around 4.5 to form free hydroxyl radicals. You need retention time, which can be determined on a bench. Size a reaction vessel such that you have enough time to break down the larger molecules. This break down, depending on stream composition, will yield additional BOD from the recalcitrant COD in the DAF influent. You use caustic to raise the pH and provide alkalinity to your biological secondary systems. Seems pretty straight forward, but you have to play with variables like soluble iron, pH, temperature, mixing, retention times, etc. to get it to work the most effectively for your stream. Changes in stream quality/composition are also going to change, but can be minimized by the EQ and DAF operation. There are several other ways of creating a free hydroxyl radical, but I find this to be the cheapest, easiest methodology. If you have further questions, then you can reach out to me directly. Sean L. Roop - BD Manager for USP Technologies - (239) 989-3581. You are simply try to make the stream more biodegradable.

Published June 22, 2018 13:24 by Sean Roop, Industrial and Engineering Consultants, LLC - Senior Water and Process Consultant

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