Project description: During its exploitation, transportation and utilization, oil will enter the atmosphere, water bodies and soil through various channels, causing serious environmental pollution. When entering the soil, part of it may be separated from the soil through volatilization, leaching, biodegradation, etc., while the remaining part remains in the soil. Such soil is called soil contaminated by crude oil and refined oil. Because oil has relatively low density, strong adhesion and low emulsification ability, it is easy to adhere to soil particles in the soil, plug soil voids, and affect soil permeability. Oil stains adhere to plant roots and form a layer of mucous membrane, which hinders the plant roots from absorbing nutrients and water, causing root rot, and affecting crop growth; petroleum can combine with inorganic nitrogen and phosphorus, resulting in a reduction in available nitrogen and phosphorus in the soil, affecting crop land nutrient absorption. A large amount of oil enters the soil, which inhibits soil microorganisms and soil enzyme activities. In addition, after petroleum substances are sent to the soil, they remain in various parts of the soil and crops, which reduces the quality of food. Polycyclic aromatic hydrocarbons in petroleum have carcinogenic, teratogenic, mutagenic and other effects, and can be gradually enriched in animals and plants through the food chain, thus indirectly affecting human health; parts of petroleum hydrocarbons that are not easily adsorbed by soil can penetrate into groundwater, pollute the shallow groundwater environment, affect the quality of drinking water, and ultimately endanger human health. At the same time, the oil content contained in soil is generally 10 - 60%, which is a valuable secondary oil resource. Recycling and resource utilization can maximize the utilization of oil and reduce soil pollution. Seeking economically feasible oil-containing soil treatment methods, improving the reliability and efficiency of traditional treatment processes, realizing resource utilization and harmless and efficient treatment of oil-containing soil, and at the same time realizing soil remediation are the development trends of oil-containing soil treatment technologies.  Innovative: The process is simple and convenient, the process is short and easy to operate, environmentally friendly, and the system is safe and reliable; the thermal desorption temperature is significantly reduced, and the efficient and rapid removal of oil from oily soil is completed under mild conditions (100-350℃); Achieve efficient separation of light gasoline and diesel oil from heavy residual oil; can maintain the original nutritional composition and texture structure characteristics; selectively carry out oily soil remediation and oil recycling.