By using the specific physical properties between oil and water, the circular steel belt continuously works to absorb and remove the floating oil on the surface of the water, reducing the degree of oil pollution to water, achieving the purpose of oil-water separation, and can be used as a pretreatment before filtration. It uses Japan’s precision oleophilic and hydrophobic oil-absorbing steel belt, which has strong grease adsorption and has the oleophilic and hydrophobic properties of only sticking to oil but not water. It is resistant to high temperature and corrosion, and is suitable for various industrial oily wastewater needs.