Research Of Oil Based Drilling Fluid Treatment Agent And Structure Of System

The main utilization system is oil based drilling fluid system in shale gas exploitation,in recent years,oil based drilling fluid treatment agents have been extensively studied.However,the phenomenon of less kinds of agents still exists and high performance agents have been monopolized by foreign companies.This paper only focuses on the development of oil-based drilling fluid treatment agents and the evaluation of their related properties.Finally,several treatment agents were applied to the oil based drilling fluid system,and a strong plugging oil base drilling fluid system was formed.There are four main achievements in this study:Based on the temperature,anhydride and fatty acid mass ratio,the optimum synthesis method of emulsifier for oil based drilling fluid was optimized by response surface methodology.Based on the CCD method,temperature 200~240 C,fatty acid(B)=80g to 90 g,anhydride(C)=14g ~ 16 g is the best synthesis method.The test shows that the 3 factors have significant effect on the electrical stability:temperature > fatty acid > anhydride.High emulsifying rate,insensitive density,good temperature resistance and good sedimentation stability of the main emulsifier have been proved by analyzing the emulsifying ratio,settling stability,density sensitivity and temperature resistance of the main emulsifier.It is a good main emulsifier.A GW-1 type oil based drilling fluid anchoring agent was prepared by condensation polymerization.When the dosage is 1.5%,excellent viscosity lifting and cutting effect is displayed.The performance of GW-1 in oil based drilling fluid system has been evaluated.The experimental data show that the anchoring agent has good thermal stability,high temperature resistance,and has the ability to improve the electrical stability of oil based drilling fluid system,greatly reducing the water loss of oil based drilling fluid;it is a high performance treatment agent.In this paper,a type of drilled plugging material is preferred.The effect of leakage is best,when 3% of the material was added.Evaluation display that the plugging agent has reasonable particle size distribution,good temperature resistance,high oil absorption expansion rate,and breakthrough pressure up to 13Mpa;and permeability leakage problem can be effectively solved.Drilled plugging agent compound plugging agent and rigid plugging agent have been mixed,the results show that the compound plugging formula can effectively solve the leakage problem of1mm-3mm cracks.It is a kind of high efficiency plugging agent.Oil based drilling fluid system has been Constructed with main emulsifier of synthetic and anchoring agent as core.Drilling plugging agent,fiber plugging agent and rigid plugging agent have been mixed into oil based drilling fluid system.Test of routine performance was tested,the results showed that it had good compatibility and strong resistance to water and salt.A set of excellent plugging oil base drilling fluid system has been formed.It has been applied in Jiao ye 195-1HF well,and achieved good application results.