After use, the quantity of DE and filtered organic solids can be about three times greater than the mass of original DE. This “extra” weight are organics that contribute to high BOD and suspended solids.
Where Does it Enter the Drain?
DE and filtered solids enter the drain when emptying and cleaning filter equipment.
How to Keep it Out of the Drain
Install the filter in an accessible location where it can be easily emptied and washed without the rinse water entering the drain.
Sweep up any DE that ends up on the floor and place into bins.
Craft brewers looking to avoid use of DE altogether can use lenticular filters and/or a centrifuge to clarify beer.
What to Do With It?
When DE is used, send the collected filter cake and all rinsed residues for composting or disposal.