棕榈油基钻井液降滤失剂的研制

棕榈油不仅具有生物降解性强、成本低、环境友好等优点，还具备了油基钻井液基液的基本功能。但由于棕榈油的组分结构与柴油、白油等存在较大区别，目前市场上的降滤失剂不适用于棕榈油基钻井液，因此需要研制适用于棕榈油的降滤失剂。分别采用干法、湿法和酰氯法对棕榈油基钻井液降滤失剂进行制备及优选，并对优选出的降滤失剂进行性能评价。结果表明，用湿法由有机改性剂SAA-6与腐植酸钠通过离子吸附反应得到的降滤失剂FLA效果最好，在棕榈油中的胶体率达到92%，最佳反应条件为95℃、2 h，腐植酸钠与有机物比为5.5。将5% FLA加入到棕榈油基钻井液中，棕榈油基钻井液的API滤失量降为4 mL以下，动切力在8 Pa左右，表现出了良好的降滤失效果，并且加入FLA的棕榈油基钻井液体系的热稳定性良好，抗高温达150℃，高温高压滤失量低于9 mL。通过实验证明，该体系抑制性、润滑性、抗污染性能、保护油气层性能以及生物毒性等能够基本满足现场钻井的需要，为促进棕榈油在钻井液领域的应用提供了实验基础。 

Development of a Filter Loss Reducer for Palm Oil Base Drilling Fluid

Palm oil has the advantages of good biodegradability, low cost and being environmentally friendly. It can be used as the base fluid of oil base drilling fluid. Palm oil has different components and molecular structures than those of diesel oil and white oil, and filter loss reducers presently available for use in conventional oil base drilling fluids cannot be used in palm oil base drilling fluid, and it is thus necessary to develop filter loss reducers special for use in palm oil base drilling fluid. Dry method, wet method and chloroformylation reaction were used to prepare and optimize filter loss reducers for palm oil base drilling fluid. Evaluation of the performance of the optimized filter loss reducer indicated that a filter loss reducer FLA made from SAA-6 (an organic modifying agent) and sodium humate through ionic adsorption reaction (wet method) had the best performance. FLA had colloidal coefficient of 92% in palm oil drilling fluid, and the optimum reaction conditions for the production of FLA was 95℃, 2 h of reaction time, and ratio of sodium humate to SAA-6 of 5.5. A palm oil drilling fluid treated with 5% FLA had API filtration rate of less than 4 mL and yield point of about 8 Pa, demonstrating good filtration behavior. The FLA treated palm oil drilling fluid had good thermal stability; it functioned properly at 150℃, and had HTHP filter loss of less than 9 mL. Laboratory experiments showed that this drilling fluid had inhibitive capacity, lubricity, contamination resistance, reservoir protective capacity and bio-toxicity that all satisfied the needs of drilling operations. This study provides an experimental base for the application of palm oil in drilling fluids.