The waste oil purification and regeneration process is also crucial for environmental protection. Currently, China's industries consume tens of millions of tons of lubricants annually, with only a small portion collected, purified, and reused, while the majority is burned or discarded. This disposal method causes significant environmental pollution, severely impacting the ecological environment and threatening people's normal lives.

Research indicates that waste mineral oil can渗透 into the soil. The oil, driven by gravity and the force of surface activity, spreads throughout the soil. The extent of this spread depends on the type and structure of the subsoil, water temperature conditions, and the density, viscosity, wetting ability, and additive content of the oil. Once the oil infiltrates the soil, it forms a "oil mass," which eventually meets the groundwater level, dissolves in the groundwater, and contaminates the underground water resources. Oxygen and microorganisms have a certain degrading effect on the oil. However, the oil that has渗入 the ground requires a considerable amount of time to be gradually degraded or oxidized. Therefore, from the perspective of environmental protection, used waste oil and waste liquids should be strictly prohibited from being carelessly poured or sprinkled.