凤河营热水储层的钻井液体系优化研究

Optimization Research of Drilling Fluid System of The Hydrothermal Reservoir in Fengheying

摘要:

凤河营位于冀中坳陷处，具有丰富的地热资源。凤河营热水储层主要是蓟县系的雾迷山组，属于碳酸盐岩裂隙，岩溶型储层。在钻井过程中，热水储层出现了漏失、粘土膨胀坍塌等事故。在分析储层地质特征的基础上，对原钻井液体系的性能进行评价。实验表明原钻井液体系的失水造壁性和堵漏能力较差。根据储层的地质特征和出现事故的机理，优化原钻井液体系的性能。原钻井液体系中加入5%超细碳酸钙和5%氯化钾之后，钻井液体系的性能得到很大改善，具有良好的流变性、较强的抑制性、良好的堵漏能力和低滤失量。优化后的钻井液体系能减少凤河营地热储层的损害。

Abstract:

There are abundant geothermal resources in Fengheying which is located at the depression of Central Hebei, and the hot water reservoir is mainly JXW, belongs to carbonate crack and karst reservoirs. There are accidents such as leakage in hot water reservoir, clay swelling and collapse in the drilling process. Based on the analysis on the geological characteristics of the reservoir, the performance evaluation is made on the drilling fluid system. The experiment shows that the original drilling fluid system had poor wall building and leakage blocking properties. According to the geological characteristics of the reservoir and the mechanism of accidents, the performance of the original drilling fluid is optimized. By adding 5% superfine calcium carbonate and 5% potassium chloride into the original drilling fluid system, the performance of new drilling fluid is greatly improved with good rheology, strong inhibition, good blocking capacity and low filtration. The damage to Fengheying geothermal reservoir can be reduced by the optimized drilling fluid system.