无固相高密度深水隔热测试液体系的制备与性能评价

Preparation and Performance Evaluation of Solid-free and High Density Insulating Testing Fluid for Deep Water

李怀科 耿 铁 罗健生 苗海龙

LI Huaike，GENG Tie，LUO Jiansheng，MIAO Hailong

深水高温高压油气井测试过程中，油气与隔水管段会与海水发生热传导和热交换，使井筒中流体的温度降低，易发生低温盐析和形成气体水合物的风险。针对这一问题，基于低导热系数流体可减小井筒流体和外界海水热交换的原理，通过对基液、加重剂、缓蚀剂的筛选，制得无固相高密度隔热测试液，对其导热系数、水合物抑制性、高压盐结晶和高温腐蚀性等性能进行了评价。结果表明，配方为 40%～ 50%低导热基液 LOWCTF+0.5%除氧剂 HBSJ-0+0.2%～ 0.3%成膜缓蚀剂 HBSJ-1+2%～ 4%钝化缓蚀剂 HBSJ-2+钙盐加重、密度为 1.05～ 1.7g/cm3的无固相高比重隔热测试液体系具有较低的导热系数（小于 0.34 W/ （m·K）），良好的水合物抑制性，在-30℃下不会出现结晶，良好的抗腐蚀性能，在 120～ 180℃下对钢片的腐蚀速率为 0.004～ 0.041 mm/a，适用于深水高温高压井作业。图 4表 3参 13

During testing process in deepwater HTHP oil and gas well，the main problem was the heat conduction and heat exchange between oil，gas，riser and outer seawater，which decreased the temperature of fluid in wellbore and easily caused salt-out and gas hydrate. Aiming at the problem and basing on the principle of heat transfer between wellbore fluid and seawater decreased by low thermal conductivity fluid，a solid-free and high density insulating testing fluid was developed through indoor selection of base fluid，aggravating agent and corrosion inhibitor. The thermal conductivity，gas hydrate inhibition，high pressure crystallization and high temperature corrosion of the fluid were studied. The results showed that the solid-free high density insulating testing fluid for deepwater HTHP well operation had low thermal conductivity that was less than 0.34 W/ （m·K），good gas hydrate inhibition without crystallization at -30℃ ，and good corrosion resistance with 0.004—0.041 mm/a corrosion rate at 120—180℃ . The solid-free high density insulating testing fluid with 1.05—1.7 g/cm3 density which was composed of 40%—50% low conductivity base fluid LOWCTF，0.5% deoxidizer HBSJ-0，0.2%—0.3% corrosion inhibitor HBSJ-1，2%—4% corrosion inhibitor HBSJ-2，and weight additive calcium salt，was suitable for the operation of deepwater HTHP wells.