Influence of cyclone oil desorption technology on the change of Oil-Based mud cuttings properties

Abstract

Shale gas exploitation produces a large amount of oil-based mud cuttings, which contains the toxic and harmful substances, posing a serious threat to the ecological environment. As a new type of pollutant separation technology, cyclone oil desorption technology is efficient, economical and environmentally friendly in the application of oil-based mud cuttings separation. This paper studies the changes in the physicochemical properties of oil-based mud cuttings before and after treatment by cyclone oil desorption technology, including composition, main elements, particle size distribution, organic and inorganic composition, heavy metal content, and the comparative analysis between recovered oil, 5 # Industrial white oil, and 0 # Diesel oil. After treatment, the oil content of oil-based mud cuttings is reduced to<1%. The H/C increased from 0.204 to 0.272 and (N + O)/C increased from 3.417 to 8.891, indicating that the degree of carbonization and hydrophilicity increased, respectively. Moreover, the mean diameter decreased from 1655.0 nm to 50.2 nm, revealing that the average particle size became 3.03% of the original. The alkanes accounted for 92.43% of the original organic composition, which was reduced to 17.35% after treatment. The heavy metal content of Ba, Zn, Cr, Ni, Pb, V and Mn still exceeds the standard after treatment. The recovered oil is easier to fractionate than 0 # Diesel oil and the safety is also better than 0 # Diesel oil. The cyclone oil desorption technology is evaluated by fuzzy comprehensive evaluation, and the result shows that it has a wide application prospect. Our research can provide guidance for the industrial treatment of petroleum hydrocarbon pollutants.