Use of Oil-Containing Sludge to Produce the Oil–Water Profile Control Agent

To address the problems of complex composition, significant property variations, and difficult and costly harmless treatment of oil-contaminated sludge in oil and gas field development, its good compatibility with the formation is leveraged to formulate it with oilfield water into an oil–water profile control agent. This reduces the cost of harmless treatment and enables resource utilization of hazardous waste. The properties of oil-contaminated sludge were evaluated experimentally. Suspending agents and stabilizers were selected according to the oil–water profile control agent preparation process, the corresponding agents were prepared, and the system was experimentally tested. The experimental results show that the suspending agent carboxymethyl cellulose (CMC) and partially hydrolyzed polyacrylamide (HPAM), and the dispersant Dodecyl dimethyl betaine (BS-12) are used to prepare oil–water profile control agent based on the selected sulfonated mud oily sludge and ground system oily sludge. The optimal formulation of profile control agent is as follows: (1) 50% ground system oily sludge +50% oilfield produced water + 0.2% CMC + 1.0% BS-12; (2) 50% sulfonated mud system oily sludge +50% oilfield produced water + 0.1% HPAM + 1.0% BS-12. The preparation of a profile control agent from oily sludge is a viable low-cost resource treatment strategy for oily sludge, which is of great significance for the environmentally friendly treatment of oil and gas field development.