1, coarse granulation method: coarse granulation method, also known as agglomeration filtration method. The use of oleophilic and hydrophobic materials, when the oily wastewater through, tiny oil beads attached to the formation of oil film on its surface, reaching a certain thickness, in the buoyancy and the role of shear force of the water flow, out of the surface of the filter media, the formation of particles of oil beads floating to the water surface, for oil-water separation. The use of coarse granulation technology can effectively reduce the oil content of restaurant wastewater, and can significantly reduce the COD concentration, which is conducive to the subsequent biochemical treatment.

2, adsorption method: adsorption method is the use of porous materials, so that one or more substances in the wastewater is adsorbed on the surface of the solid and remove the method. According to the different adsorption force on the solid surface, can be divided into physical adsorption and chemical adsorption.

3, air flotation: air flotation method is to produce a large number of micro-bubbles through a certain method, so that it is close to the density of wastewater in the water solid or liquid pollutants particles adhering to the formation of density less than the water of the air float, floating to the surface of the water to form a flotation, for separation. It is mainly used to remove suspended solids, oils and fats with specific gravity less than 1. Combined with the use of flocculants, the removal effect can also be further improved. The air flotation method has better results and occupies a small area.