Fault fractures usually have large openings and considerable extension. Accordingly, cross-linked gel materials aregenerally considered more suitable plugging agents than water-based gels because the latter often unde...Fault fractures usually have large openings and considerable extension. Accordingly, cross-linked gel materials aregenerally considered more suitable plugging agents than water-based gels because the latter often undergo contaminationvia formation water, which prevents them from being effective over long times. Hence, in this study, aset of oil-based composite gels based on waste grease and epoxy resin has been developed. These materials havebeen observed to possess high compressive strength and resistance to the aforementioned contamination, therebyleading to notable increase in plugging success rate. The compressive strength, thickening time, and resistance toformation water pollution of these gels have been evaluated indoors. The results show that the compressivestrength of the gel can reach 11 MPa;additionally, the related gelation time can be controlled to be more than3 h, thereby providing a safe construction time;Invasion of formation water has a small effect on the gel strengthand does not shorten the thickening time. All considered performance indicators of the oil-based gel confirm itssuitability as a plugging agent for fault fractures.展开更多
采用常规可固化堵漏剂解决低压地层裂缝性漏失时会产生密度过大或承压不足的技术难题,因此研究低密度高抗压的堵漏体系具有重要意义。通过合成聚丙烯酰胺(polyacrylamide,HPAM)交联形成有机网络,并优选水泥材料形成无机网络,构建低密度...采用常规可固化堵漏剂解决低压地层裂缝性漏失时会产生密度过大或承压不足的技术难题,因此研究低密度高抗压的堵漏体系具有重要意义。通过合成聚丙烯酰胺(polyacrylamide,HPAM)交联形成有机网络,并优选水泥材料形成无机网络,构建低密度有机-无机互穿网络堵漏体系;采用模拟水驱实验、X射线衍射、扫描电子显微镜(scanning electron microscope,SEM)、高温高压(high temprature and high pressure,HTHP)堵漏模拟实验、抗压实验等分析了堵漏体系的性能和堵漏机理。结果表明,聚丙烯酰胺交联反应形成的有机网络与水泥水化形成的无机网络通过静电力和范德华力等作用可形成互穿网络体系,体系抗压达6.3 MPa,密度为1.28 g/cm^(3),固化时间实现2~5 h可控,固化前后的酸溶率分别为87.8%和63.4%,堵漏及解堵性良好。展开更多
In view of the shortcomings of poor temperature resistance, poor pumpability and poor pressure-bearing capacity of commonly used gel plugging materials, polyacrylamide (HPAM) and N,N-methylene bisacrylamide (BIS) were...In view of the shortcomings of poor temperature resistance, poor pumpability and poor pressure-bearing capacity of commonly used gel plugging materials, polyacrylamide (HPAM) and N,N-methylene bisacrylamide (BIS) were selected for crosslinking and compounding to make a new type of gel plugging material with high temperature and pressure resistance. The compressive strength and yield stress were measured by inverted observation method to evaluate the gel strength. The anti-temperature, anti-pressure, anti-dilution and gel-breaking properties of the gel were evaluated. Finally, 71 type high temperature and high pressure water loss instrument and high temperature and high pressure filter with slit plate were used to evaluate the plugging capacity of gel plugging agent. The experimental results show that the new gel plugging system between 100°C - 120°C, gelation time can be controlled at about 5 h;it has strong temperature resistance, compression resistance, dilution resistance and gel breaking performance. In the face of permeability and fracture leakage simulation experiments, when the ambient temperature below 120°C, pressure within 5 MPa, the filter loss of gel plugging agent is far less than the market two conventional plugging agent, has excellent plugging performance.展开更多
基金“Research and Application of Key Techniques for Drilling and Completion of Bozhong 19-6 Condensate Gas Field Development-Phase I”sub topic 4“Research on Leakage Prevention and Plugging Techniques for Fault and Buried Hill Reservoirs”,a Project of China National Offshore Oil (China)Co.,Ltd. (Project No.YXKY-2020-TJ-03).
文摘Fault fractures usually have large openings and considerable extension. Accordingly, cross-linked gel materials aregenerally considered more suitable plugging agents than water-based gels because the latter often undergo contaminationvia formation water, which prevents them from being effective over long times. Hence, in this study, aset of oil-based composite gels based on waste grease and epoxy resin has been developed. These materials havebeen observed to possess high compressive strength and resistance to the aforementioned contamination, therebyleading to notable increase in plugging success rate. The compressive strength, thickening time, and resistance toformation water pollution of these gels have been evaluated indoors. The results show that the compressivestrength of the gel can reach 11 MPa;additionally, the related gelation time can be controlled to be more than3 h, thereby providing a safe construction time;Invasion of formation water has a small effect on the gel strengthand does not shorten the thickening time. All considered performance indicators of the oil-based gel confirm itssuitability as a plugging agent for fault fractures.
文摘采用常规可固化堵漏剂解决低压地层裂缝性漏失时会产生密度过大或承压不足的技术难题,因此研究低密度高抗压的堵漏体系具有重要意义。通过合成聚丙烯酰胺(polyacrylamide,HPAM)交联形成有机网络,并优选水泥材料形成无机网络,构建低密度有机-无机互穿网络堵漏体系;采用模拟水驱实验、X射线衍射、扫描电子显微镜(scanning electron microscope,SEM)、高温高压(high temprature and high pressure,HTHP)堵漏模拟实验、抗压实验等分析了堵漏体系的性能和堵漏机理。结果表明,聚丙烯酰胺交联反应形成的有机网络与水泥水化形成的无机网络通过静电力和范德华力等作用可形成互穿网络体系,体系抗压达6.3 MPa,密度为1.28 g/cm^(3),固化时间实现2~5 h可控,固化前后的酸溶率分别为87.8%和63.4%,堵漏及解堵性良好。
文摘In view of the shortcomings of poor temperature resistance, poor pumpability and poor pressure-bearing capacity of commonly used gel plugging materials, polyacrylamide (HPAM) and N,N-methylene bisacrylamide (BIS) were selected for crosslinking and compounding to make a new type of gel plugging material with high temperature and pressure resistance. The compressive strength and yield stress were measured by inverted observation method to evaluate the gel strength. The anti-temperature, anti-pressure, anti-dilution and gel-breaking properties of the gel were evaluated. Finally, 71 type high temperature and high pressure water loss instrument and high temperature and high pressure filter with slit plate were used to evaluate the plugging capacity of gel plugging agent. The experimental results show that the new gel plugging system between 100°C - 120°C, gelation time can be controlled at about 5 h;it has strong temperature resistance, compression resistance, dilution resistance and gel breaking performance. In the face of permeability and fracture leakage simulation experiments, when the ambient temperature below 120°C, pressure within 5 MPa, the filter loss of gel plugging agent is far less than the market two conventional plugging agent, has excellent plugging performance.