Trash tank
Solids settle. Grease floats. Only the middle moves on.
The first compartment separates the waste stream by density. Heavy solids form sludge on the floor, fats and oils form a scum layer at the surface, and relatively clear liquid in between passes forward to treatment.
What it means for you
This is the layer that pumping removes. Left too long, sludge migrates forward and damages the parts that cost real money.
