A point source grease separator commonly called a Portable Grease Trap in Singapore, is a plumbing device installed under a washing sink and designed to remove grease, oil, and fats from wastewater before it enters the sewage system or septic tank. It is used in commercial kitchens, restaurants, and other food service establishments where large amounts of grease are generated.

The purpose of a grease separator is to prevent the accumulation of grease in the sewer lines, which can cause blockages and other plumbing issues. The separator works by slowing down the wastewater flow and allowing the grease to rise to the surface. Solids and heavier particles settle to the bottom of the tank, forming a layer of sludge. The grease is then trapped in the device while the relatively cleaner water flows out through an outlet.

The grease can be periodically removed from the separator and properly disposed of, usually by a licensed waste hauler.