From: Jason Clifford

Sent: Mon Jan 30 12:37:58 2017

To: Gerald Fisher

Subject: digesters

Importance: Normal

Hello Gerald,

Ryan was here on Thursday. I told him I’d email you about the digester project. I recommend (2) 20,000 gallon digesters, (3) blowers; one for each digester and a backup. The three blowers should be valved so each digester can use any of the three. A submersible pump in the skimmings wet well to pump to the digesters. Repiping of the backwash and drain lines from the filters; too much clear water to the digesters will thin out the solids. Pipe from the digesters to the side road northwest of filter #2. And an FKC screw press. (2) digesters is good for maintenance, decanting and emergency storage, if needed. I’ll have a chemical supplier come and perform jar testing to get the right polymer for flocculation. After that, I’ll dial the screw press. Ideally, we would want to see about 20% dried solids (cake), to reduce dumping fees. BOD and TSS are not required for digester sizing as they’re just aerated holding tanks until the contents go through the screw press. I would usually run my press all week and turn it off on the weekends to fill the digester with fresh solids and decant as needed.

Thanks,

Jason