In the process of drilling, finishing and work-over, water blocking damage in low permeability reservoir is usually prevented by adding anti-water blocking agent into the working fluid. The traditional anti-water blocking agent was a surface active agent and cannot simultaneously reduce the gas-iquid, liquid-liquid and solid-liquid interfacial tension, and salt tolerance was poor. In order to solve this problem, a compound fluorocarbon anti-water blocking agent DF-FSS02 was developed. Laboratory experiments show that control fluid joined with anti-water blocking agent DF-FSS02 does not blister when stirring. When the amount of dosage is 0.10%, the surface tension and the interfacial tension are decreased by 56.92% and 86.52%, respectively. Water blocking damage can be relieved when the dosage of DF-FSS02 is added up to 5.00%; water blocking damage can be prevented by adding 0.20%, and DF-FSS02 has good compatibility with formation water and control fluid. The ant-water blocking agent is currently used in five wells in Lingxing Block, of which four wells have reached forecast proration production. The anti-water blocking agent has shown good effect on reducing the water blocking damage in both laboratory and field applications, and has remarkable significance for the development of low porosity and low permeability oil and gas fields.
论文详情