A study of the capillary rise characteristics of LNAPL based on the vertical pipes method

The pollution caused by light non-aqueous phase liquid (LNAPL) and its derivatives, known as "industrial blood", in the process of mining, production and transportation, has become a common pollutant. At present, many researchers have carried out extensive researches on LNAPL pollution, but the researches on the migration and hairiness of LNAPL in soil is still insufficient. The purpose of this test is to study and analyze the capillary rise law of LNAPL in different media under different standpipe diameters through indoor simulation tests, so as to provide a certain theoretical basis for studying the groundwater pollution caused by LNAPL. The results show that the factors influencing the height of capillary rise are, in order, the solution > medium> vertical tube diameter. The diameter of the vertical tube is not completely proportional to the maximum capillary rise height, and the influence on the capillary rise height is relatively small. The capillary rise height and capillary rise rate of water and diesel in different media are basically the same, but there are differences in specific values. The maximum capillary rise height of diesel is 40%−50% lower than that of water, and the maximum capillary rise rate of diesel is 30%−50% lower than that of water. The average particle size of sand is inversely proportional to the capillary rise height and rate. These characteristics can better reflect the capillary rise law of LNAPL in different media, which are of important significance to understand the pollution of LNAPL to groundwater and the remediation of contaminated lands.