Grease Trap for Commercial Sinks | FOG Removal & Custom Solutions

A grease trap for commercial sinks is a compact pretreatment device used to remove fats, oils, grease, floating scum and some food solids from kitchen wastewater. It is also called a commercial grease interceptor, kitchen grease separator or sink grease trap. Its main purpose is to protect drainage pipes, reduce sewer blockage and lower the oil load entering downstream wastewater treatment systems.

In commercial kitchens, wastewater from sinks often contains cooking oil, animal fat, vegetable oil, sauces, food scraps and detergents. If this wastewater is discharged directly, grease may cool down and stick to the pipe wall. Over time, this can cause slow drainage, odor, pipe blockage, maintenance cost and possible compliance problems.

The working principle is simple. Wastewater enters the grease trap through the inlet pipe. Inside the tank, the flow slows down. Because grease is lighter than water, it floats to the top. Heavier food particles and solids settle at the bottom. The middle water layer flows through the outlet to the drainage system or further treatment unit.

A typical process is:

A grease trap may include an inlet pipe, flow baffle, separation chamber, grease storage zone, solids collection area, outlet pipe, removable cover, sealing structure and optional cleaning access. For commercial use, stainless steel is widely preferred because it is corrosion-resistant, hygienic and easier to clean. Depending on the project, carbon steel, FRP or other materials may also be considered.

Selection should not be based only on tank appearance. Important factors include sink quantity, drainage flow rate, peak water discharge, kitchen operating hours, grease load, food solids content, installation space, indoor or outdoor placement, cover opening direction, odor control and local discharge requirements. A small under-sink grease trap may be suitable for light-duty kitchens, while larger restaurants, hotels or food production sites may need a bigger floor-mounted or buried grease interceptor.

It is important to understand the application boundary. A grease trap mainly removes separable fats, oils, grease and settleable solids. It does not remove dissolved organic pollutants, emulsified oil, detergents, high COD or nutrients completely. If the outlet water must meet stricter discharge or reuse standards, the grease trap may need to work with DAF, biological treatment, filtration or packaged sewage treatment equipment.

Regular maintenance is essential. Operators should remove accumulated grease and settled solids before storage capacity is exceeded. If cleaning is delayed, grease may escape through the outlet, cause odor or reduce separation efficiency. Cleaning frequency depends on kitchen usage, grease load and tank size.

Qingdao Jinwantong can provide customized grease separation and wastewater pretreatment solutions for commercial and industrial users. Buyers can send sink quantity, flow rate, kitchen type, installation space, preferred material and discharge target for technical selection and quotation.