摘要
深井长封固段固井对水泥浆体系性能要求严苛,既要保证高温下安全泵送,又要保证顶部水泥石早期强度较快发展缩短建井周期,现有缓凝剂常表现为温度越高缓凝作用越弱、温度越低缓凝作用越强,甚至出现长时间不凝固的不利现象。为此,合成出一种具有温度响应自组装特性的两亲聚合物高温智能缓凝剂TRAP。通过低温下疏水基团分子自组装为有序排列构象将缓凝基团包裹,阻止缓凝基团吸附在水泥颗粒表面,降低低温缓凝的副作用,高温下分子构象从有序转变为无序,显露更多缓凝基团吸附于水泥颗粒表面,展现出充分的高温缓凝效果,实现了缓凝作用随温度变化而自行智能调控作用,为解决深井大温差固井难题提供了一种新方法。研究结果表明:两亲聚合物缓凝剂TRAP耐温性能优异,在30~200℃能延长水化诱导期,有效增大水泥浆稠化时间,在130~190℃范围内,缓凝性能随温度升高显著增强,最高与最低温度稠化时间仅差69 min,表现出随温度升高缓凝作用智能增强的调控特性;模拟井底180℃高温循环固井条件,顶部上返水泥浆早期强度发展快,水泥石在90℃、24 h的抗压强度达16.3 MPa,将固井候凝时间大幅度缩短至24 h。缓凝剂TRAP独特的温度智能响应特性,不同且显著优于现有大温差缓凝剂的调控规律与效果,为解决深井长封固段固井的高温稠化时间与顶部低温早期强度调控难题提供了一种新方法。
Cementing in long sealing section of deep wells requires high performance cement slurry system,which needs to ensure not only safe pumping at high temperature,but also a rapid early strength development in the top cement stone for shortening the cycle of well construction.However,the retardation effect of existing retarders becomes weaker as temperature increases,and increases as temperature decreases,which may lead to an unfavorable phenomenon that cement slurry does not solidify for a long time.Therefore,an amphiphilic polymer high-temperature intelligent retarder TRAP is innovatively designed and synthesized,which possesses self-assembly and temperature response properties.At low temperature,hydrophobic group molecules are self-assembled into well-arranged conformation to wrap the retarding groups,which can prevent retarding groups from adsorbing on the surface of cement particles and reduce the side effects of the retarder at low-temperature.At high temperature,the molecular conformation changes from being ordered to being unordered,for which more retarding groups are adsorbed on the surface of cement particles.This demonstrates a complete high-temperature retarding effect,which has achieved intelligent regulation of retarding effect with temperature change,thus providing a new method for solving the difficulty in deep well cementing due to large temperature difference.The research results show that TRAP has excellent high temperature resistance,which can prolong hydration induction period and effectively prolong the thickening time of cement slurry at 30 ℃ to 200 ℃.Within the temperature range of 130 ℃ to 190 ℃,the retardation performance of TRAP can increase significantly with the increase of temperature,and the thickening time difference between maximum and minimum temperatures is only 69 minutes,which witnesses the regulation characterized by intelligent enhancement of retarding effect with temperature increase.By simulating the conditions of high-temperature cycle cementing at 180 ℃ at the well
作者
薛毓铖
王成文
陈泽华
孙金声
唐伟旭
武治强
刘伯诺
黄康
Xue Yucheng;Wang Chengwen;Chen Zehua;Sun Jinsheng;Tang Weixu;Wu Zhiqiang;Liu Bonuo;Huang Kang(National Key Laboratory of Deep Oil and Gas,China University of Petroleum,Shandong Qingdao 266580,China;School of Petroleum and Engineering,China University of Petroleum,Shandong Qingdao 266580,China;Key Laboratory of Unconventional Oil and Gas Development,Ministry of Education,Shandong Qingdao 266580,China;PetroChina Daqing Petrochemical Company,Heilongjiang Daqing 163714,China;CNOOC Research Institute Co.,Ltd.,Beijing 100028,China)
出处
《石油学报》
EI
CAS
CSCD
北大核心
2023年第9期1532-1544,共13页
Acta Petrolei Sinica
基金
国家自然科学基金基础科学中心项目“超深特深层油气钻采流动调控”(No.52288101)
国家自然科学基金项目“自组装/纳米SiO2热增黏聚合物及其调控超深井高密度水泥浆恒匀机理研究”(No.52074329)
泰山学者青年专家项目(tsqnz20221122)
山东省自然科学基金项目“CO2驱组分演化中CO2与油气烃分子的微观混合机制”(ZR2021QE153)资助。
关键词
深井
大温差
高温缓凝剂
两亲聚合物
固井水泥浆
稠化时间
水化机制
deep well
large temperature difference
high-temperature retarder
amphiphilic polymer
cement slurry
thickening time
hydrationmechanism
