生物柴油包水钻井液体系

生物柴油主要成分是脂肪酸烷基酯，其闭杯闪点高不易着火，且不含或含少量硫和芳香烃，其性能稳定、毒性低、无荧光性，对测井无影响，是良好的酯基钻井液基液。因常规油基钻井液处理剂与生物柴油配伍性较差，笔者针对生物柴油包水钻井液的处理剂进行了优选，优选出主乳化剂TC-PEM、辅乳化剂TC-GSEM、提切剂UP-GEL和降滤失剂UPGEL，并通过对生物柴油包水钻井液性能评价实验，研制出3种不同密度的生物柴油包水钻井液体系。该体系具有良好的抗温性，抗温为120℃，抗淡水侵能力为15%、抗CaO能力为2%；生物柴油包水钻井液体系生物降解性评级为容易，是一种环境友好型钻井液体系。现场应用表明，该钻井液具有良好的流变性能，提高了机械转速，大幅度缩短了建井周期。 

Laboratory Study on Water in Oil Drilling Fluid Formulated with Biodiesel Oil

Biodiesel, mainly composed of fatty acid alkyl esters, is a good base fluid for making ester-base drilling fluid because of its many advantages, such as high closed-cup flashing point (thus can avoid catching fire), no or a small amount of sulfur and aromatic hydrocarbons contents, stable properties, low toxicity and non-fluorescence. It has no impact on wireline logging. Several oil base mud additives, such as the primary emulsifier TC-PEM, the secondary emulsifier TC-GSEM, the gelling agent UP-GEL and filter loss reducer XXX were optimized to overcome the poor compatibility of the oil base mud additives with biodiesel. Three biodiesel oil base drilling fluids were formulated with these additives through property evaluation. These biodiesel oil base drilling fluids have good thermal stability (resistant to temperature of 120 ℃), good performance in resisting fresh water invasion (15%) and CaO contamination (2%). The biodiesel oil base drilling fluids have a degradability level of “easy to degrade”, and are thus environmentally friendly.