Preparation and Properties of Seawater-based Clean Fracturing Fluid PA—VES90

In order to reduce the fracturing cost of offshore oil field,developed and researched seawater-based clean fracturing fluid PA—VES90 which prepared with sea water,fresh water or formation water,and achieved industrial production of main agent PA—1 and activator PA—JX1.Evaluation results show that: PA—VES90 fracturing fluid shearing 1.5 h at 90 ℃,170 s-1,the viscosity in the 40 mPa·s above,proppant carrying capacity meets the requirements of the scene construction requirements.And the system gel was breaking simply and completely,using 2% crude oil or diesel as gel breaker,completely broken in 2.5 h,and breaking agent has a low surface tension,easy to flow back.The injury rate is less than 10%.Prepared clean fracturing fluid with field water,which is no precipitation and flocculation,compatibility with formation fluid is good.