SYNTHESIS AND PROPERTIES EVALUATION OFORGANIC CLAY FOR BIODIESEL BASED DRILLING FLUID

摘要

Organic clay is an important part of oil based drilling fluid.It has better viscosity increasing, and can greatly improve the rheological properties and cuttings carrying capacity of oil-based drilling fluid system. Due to the complex composition of bio-diesel, the effect of increasing viscosity and improv-ing the gel performance of biodiesel is generally poor. Therefore, there are few organic clay suitable for biodiesel based drilling fluids in the market. In view of the deficiency of the performance of bio-diesel based drilling fluid, based on the investigation of bentonite source, orthogonal design method and single factor analysis experiment method were adopted to modify the sodium bentonite with quater-nary ammonium salts. After modification,organic clay for biodiesel based drilling fluid were obtained. The structure of the organic clay was characterized with FT-IR, XRD, SEM and TGA. Their properties in biodiesel oil was investigated before and after thermal aging at various temperatures. The results indicated that the organic clay had excellent proper-ties of improving the rheological properties of bio-dieselbased drilling fluid. It is high temperature tol-erant to 240-250°CC,showing promise in biodiesel based drilling fluid.