Equipment Involve in Grease Trap/Tank

As I said earlier, common grease tank located after grit tank. Saturated fat will be accumulated on top/surface of water. You will the accumulation in yellow color. The accumulation need to be removed to makesure optimization for downstream treatment process.

Removal equipment is called scum/oil/fat skimmer. Two type of scum skimmer normally seen in Sewage Treatment Plant (STP) which are pump/motor driven type and airlift driven type. The suction produce during its operation will skim out floating fat and drive the product to drying bed or dewatering unit before it can be dumped outside. Picture of equipment were as below:

Motor driven scum skimmer

Airlift driven scum skimmer

Problem may appear with these equipment are bloockage due to improper rugs (normally plastic and diapers/pad) screening at earlier stage and broken of suction pipe and etc.

Equipment in Grit Trap (Tank)

Normally, grit tank will be equipped with grit pump, to remove bottom's settled grit. For a big construction of sewage water treatment, the removal equipment may use airlift system to remove bottom product. Airlift system is a principal system that involve pressure gradient in a pipe. The design of airlift were illustrated as below: