Migration characteristics of oils in soil

With the growth of population and the continuous increase of industrial and agricultural production scale in China, the soil pollution has become increasingly severe, and the pollution of petroleum contaminants to the soil is currently one of the most prominent problems of soil pollution. In this paper, the soil column experiment in the laboratory was carried out by simulating field soil density and water conditions, and the capillary rise, infiltration and horizontal migration characteristics of 0^# diesel oil in aqueous soil were studied, so as to understand the migration behavior of petroleum contaminants in soil and provide the basis for the pollution control and treatment after oil leakage. It is indicated that the square of the rising height in the initial and final stages of the migration is in linear relationship with the time in the capillary rise process of the diesel in the soil column. After the oil leakage, the main migration mode of the contaminated soil is gravity infiltration. In the condition of large granular soil, the migration of diesel is mainly in the mode of gravity infiltration, while in the condition of small granular soil, it is significantly affected by the capillary effect. Diesel's infiltration rate is obviously higher than its capillary rise rate. Diesel's migration rate is much higher than its capillary rise rate in its initial stage of horizontal migration, while they both tend to be the same in the final stage, indicating that the spreading effect of molecular level is less affected by the gravity.