| 摘要 |
Oil residues are removed from contaminated solids, in particular from cuttings produced from drilling a borehole using an oil-based drilling fluid, by contacting the solids with a washing fluid which comprises carbon dioxide and cosolvent under conditions at which carbon dioxide is a supercritical fluid and the cosolvent is in solution in the supercritical carbon dioxide, and then separating washed solids from the washing fluid; wherein the washing fluid comprises at least 5% by volume of co-solvent which is one or more organic compounds with a Hildebrand solubility parameter in a range from 16 to 21 MPa1/2. The washing process may be applied to drilling cuttings produced offshore. The co-solvent may include at least one of a cycloaliphatic ring, an olefinic unsaturation, an ester group and an ether group, and may be d-limonene, α-pinene, methyl ester of soybean oil, cyclohexane or glyceryl palmitate. |
