Scum Management
Scum Management
(OP)
I am currently working on a WWTP upgrade and my supervisor and I are running into a problem deciding what to do with the scum out of the primary clarifiers.
Currently the scum is skimmed into a trough and routed into a "scum concentration box." Once the grease and scum coagulate the material is then removed via manual labor.
My supervisor is considering removing the scum out of the concentration box via a chopper pump and recirculating it back through the plant or piping it into the proposed liquid sludge storage tank. [NOTE: After the liquid sludge storage the sludge will be thickened and ran through an ATAD System]
I am green behind the ears being a recent college graduate and have little valuable opinion on the situation. I however did want to research it the best I could to help his decision.
I was also interested in learning what is typically done on new construction jobs as well; merely for my own learning purposes. Most literature just mentions removing scum out of the primary clarifiers but doesn't mention what happens after that.
Thanks for your time,
Matthew Peters
Currently the scum is skimmed into a trough and routed into a "scum concentration box." Once the grease and scum coagulate the material is then removed via manual labor.
My supervisor is considering removing the scum out of the concentration box via a chopper pump and recirculating it back through the plant or piping it into the proposed liquid sludge storage tank. [NOTE: After the liquid sludge storage the sludge will be thickened and ran through an ATAD System]
I am green behind the ears being a recent college graduate and have little valuable opinion on the situation. I however did want to research it the best I could to help his decision.
I was also interested in learning what is typically done on new construction jobs as well; merely for my own learning purposes. Most literature just mentions removing scum out of the primary clarifiers but doesn't mention what happens after that.
Thanks for your time,
Matthew Peters





RE: Scum Management
You best option is to install a heated decant tank to collect the scum. You can then have the scum sent offsite for disposal after you have decanted the free liquid. A disposal vac truck can suck the material out of the decant tank. No shoveling involved.
Scum handling is frequently overlooked. Many plants do not process the scum. It is collected and then shifted somewhere else in the treatment plant where it may cause other problems. Scum tends to move around in the treatment plant and then return. You are better off just removing it and sending it off for disposal.
There are numerous treatment schemes for scum. These include anaerobic digestion, incineration, chemical fixation with lime,
The best value for the average treatment plant is sending it off site for processing and disposal.
RE: Scum Management
Steve
RE: Scum Management
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Scum Management
RE: Scum Management
http://www.envirocare.com/files/ScumBro.pdf
RE: Scum Management
Problem is that scum can take a lot of water to move and / or unblocking of pumps - but it sounds like it may be worth while and not uncommon. Could you trial it first?