抗高温高密度生物质钻井液体系研究及应用

为了提高抗高温高密度钻井液体系的高温稳定性及环保性能，以自主研发的生物质合成树脂降滤失剂、抑制剂和润滑剂为核心处理剂，对处理剂加量进行优化，构建了抗高温高密度生物质钻井液体系。性能评价结果表明:该体系抗温可达200 ℃，抗1.0%CaCl₂污染，岩屑滚动回收率达94.3%，润滑系数≤0.128，生物毒性EC₅₀为89 230 mg/L。现场应用表明，抗高温高密度生物质钻井液具有较好的抗污染能力，在密度达2.55 kg/L、井底温度达140 ℃的情况下其仍具有很好的流变稳定性能。抗高温高密度生物质钻井液促进了生物质资源在钻井液领域的利用，解决了高密度水基钻井液抗温性与环保性相矛盾的问题，具有较好的现场推广应用价值。 

Research and Application of a High-Temperature Resistant and High-Density Biomass Drilling Fluid System

In order to improve the temperature stability and environmental protection performance of a high-temperature resistant and high-density drilling fluid system, the self-developed filtrate reducers, inhibitors, and lubricants with biomass synthetic resin were taken as the core treatment agents, the dosages of the treatment agents were optimized, and a high-temperature resistant and high-density biomass drilling fluid system was constructed. The performance evaluation results showed that the system could resist temperature up to 200 °C. It also could resist CaCl₂ pollution of 1%. The rock cuttings rolling recovery was 94.3%, with the lubrication coefficient ≤ 0.128. The biological toxicity EC₅₀ value was 89 230 mg/L. The field application showed that the high-temperature resistant and high-density biomass drilling fluids could significantly resist pollution. They had excellent rheological stability when the density was up to 2.55 kg/L and the bottom hole temperature was 140 °C. The high-temperature resistant and high-density biomass drilling fluids can promote the utilization of biomass resources in the drilling fluid field and solve the trade-off between the temperature resistance and environmental protection of high-density water-based drilling fluids. Therefore, the drilling fluids have positive field promotion and application value.