八角场气田大型加砂压裂工艺实践

PRACTICE OF LARGE-SCALE SAND FRACTURING AT BAJIAOCHANG GASFIELD IN THE SICHUAN BASIN

针对低渗低孔高压、砂体厚度大和储集丰度低的八角场气田,大型加砂压裂是勘探开发该气田的有效手段,而如何成功有效地进行大型加砂压裂作业就成了工作的重中之重。一方面,大型加砂压裂作业成功有两大难点:①由于储层是典型的低渗低孔高压储层,裂缝的增长速度快,动态缝宽窄,加之砂体厚度大,为确保支撑剂顺利进入储层,需要大排量施工;②压裂规模大,作业时间长。另一方面,大型加砂压裂作业有效,需有机地匹配和优化储层、压裂液和工艺,并系统地控制压裂质量。文章以角X井为例,拟就储层概况、测试压裂、设计优化、压裂质量控制等方面分析如何优质完成大型加砂压裂工程,从而提高压裂施工效果,优化投入产出。

The Bajiaochang gasfield in the Sichuan Basin is a low-permeability, low-porosity high pressure gas field, with thick sand bodies and low reservoir abundance. Large-scale sand fracturing is an effective technology to develop this gas field. But challenges still exist. On one hand, there are two difficulties to be solved. One is high flow rate required to ensure proppants effectively pumped into the pay zone; the other is long operation time needed due to large scale of the operation. On the other hand, the effective large-scale sand fracturing requires optimum reservoir formation, fracturing fluid and techniques, and systematic control of the fracturing quality. The Well Jiao-X is taken as an example to make analysis on reservoir condition, fracturing test, optimization design and quality control, so as to ensure success and high quality of large-scale sand fracturing to optimize ROI ratio.