High Temperature And High Viscosity Acid Synthesis Of Gelling Agent And The Acid System

Acid and frac treatment is one important measure for hydrocarbon reservoir to increase production, the performance of acid and frac working liquid and acidizing fluid additive directly affect the effect of acid and frac treatment, especially for deep wells with high temperature and low permeability. At present, under the deep well condition with high temperature, the routine acidizing fluid has limited ability of slowing rate , can not form the longer acid etching fracture hat has some sustaining ability. ,This paper aims at the sutural carbonate rock reservoir in Ordovician TaHe oilfield. Two new kinds of polymer sour liquid gelling agents (PDA and PDMC) have been synthesized. The gelling agent PDA is the copolymer of methacryloyloxyethyl trimethyl ammonium chloride (DMC) and acrylamide (AM); the gelling agent PDMC is the homopolymer of DMC. The influential factors of polymerization reaction have been studied ( such as catalyst, pH, mass ratio of monomers, total concentration of monomers, the type and mass of initiator, temperature and reaction time etc.) IR and the H-NMR structural symptom have been carried out for composing outcome. Performance appraisement shows: It has good tackify effect, temperature-tolerance performance, and compatibility with various acidizing liquid additives.In this paper, using the gelling agent synthesized by myself as host agent, two sets of working liquids that meet the acid and frac treatment in deep wells with high temperature have been developed : the jell acid system and low solidoid gelling acid system. Special for high temperature low solidoid gelling acid system, it dropped the polymer content from 0.8% ~ 1.0% in the common acid liquid to 0.5% ~ 0.6% , reduced 40% — 50% polymer dosage, so it can reduce the potential injury to reservoir bed causing by polymer in process of acid and frac treatment.In this paper, the rheological property of gelling acid system, the reaction dynamics parameter of acid-rock and the flow conductivity of acid-etching fracture had still been completely studied. It offered scientific basis for optimization acidtreatment. Show as a result: The acid liquid has good temperature-tolerance performance; it also can reduce the filtration efficiently and delay acid - rock reaction speed. The system can satisfy completely the requirements of acid and frac treatment in carbonate rock reservoir in Ordovician TaHe oilfield. For other oilfields of our country, it also has realistic meaning.