EXPERIMENTAL STUDY ON HARMLESS TREATM ENT TECHNOLOGY OF OIL-BASED DRILLING FLUID SOLID WASTE BASED ON A NOVEL CHEMICAL CURING AGENT

摘要

Shale gas resources have become one of the hot exploration and development targets for global oil and gas resources, and oil-based drilling fluids are currently the main type of drilling fluid for shale gas drilling. The environmentally friendly disposal of oil-based drilling fluid waste has become an urgent technical problem. In this paper, based on the use of oil-based drilling fluid in Fuling Shale Gas Field and the technical idea of solidification treatment, we tested the main components and physical and chemical properties of oil-based drilling fluid solid waste indoors, and investigated the effects of various types of curing agents. Finally, a new composite curing agent OBJ-1 was prepared. On this basis, the optimal addition amount, curing temperature and curing time of OBJ-1 were investigated by experiments. The experimental results show that OBJ-1 is a powder solid preparation, which is safe and easy to store and transport. The optimized mass ratio of OBJ-1 to oil-based drilling fluid solid waste is 1:9, the optimized curing temperature is 70-80 °C, and the optimized curing time is 180 min. The residual oil content and COD value of the waste liquid after curing meet the discharge requirements. OBJ-1 is mainly composed of a variety of high-priced ionic polymers. It has strong adsorption capacity for oil-based drilling waste and can quickly break the colloidal continuity of drilling waste. This technology is expected to solve the current environmental pollution problem of oil- based drilling fluid solid waste, and can obtain significant economic benefits.