This project is explaining a laboratory development of a solid free drilling fluid formula that could be potentially used in tight gas reservoirs. The configuration of the weak gel fluid WGL-1, which is resistant to h...This project is explaining a laboratory development of a solid free drilling fluid formula that could be potentially used in tight gas reservoirs. The configuration of the weak gel fluid WGL-1, which is resistant to high temperature and high salt, was tested, and concluded that its gelling properties, salt and temperature resistance, and environmental protection were all in line with industry requirements. The final drilling fluid formula was developed as: water + (0.3% ~ 0.5%) NaOH + 5% KCl + 2% WGL-1 + 5% NaCl + (1.0% ~ 2.0%) HBFR Anti-high temperature fluid loss agent + 2% Polyol + (1.5% ~ 2.0%) SDL-1 Lubricant + 0.4% A4O1. The performance of the liquid was tested for temperature resistance, inhibition, gas formation protection effect, plugging performance, and static settlement stability. It was concluded that the temperature resistance performance is satisfied at 150°C, and the cuttings recovery rate is as high as 96.78%. It has good performance in inhibiting water dispersion and swelling of cuttings. The permeability recovery value reaches 88.9%, which meets the requirements of gas formation protection. The SSSI value shows that its settlement stability is good;under high temperature and high pressure, its sealing performance is good. This drilling fluid system has achieved the expected results and laid a foundation for further promoting the development of solid-free drilling fluid systems. The future development direction of solid-free drilling fluids is pointed out, to the improvement of properties to be applied in high temperature environment and have high salt resistance capacity.展开更多
There are many problems associated with coiled tubing drilling operations, such as great circulation pressure loss inside pipe, difficulties in weight on bit(WOB) transferring, and high probability of differential sti...There are many problems associated with coiled tubing drilling operations, such as great circulation pressure loss inside pipe, difficulties in weight on bit(WOB) transferring, and high probability of differential sticking. Aiming at these problems, solids-free brine drilling fluid system was developed on the basis of formulation optimization with brine base fluid experiment, which was evaluated and applied to field drilling. Based on the optimization of flow pattern regulator, salt-resisting filtrate reducer, high performance lubricant and bit cleaner, the basic formula of the solids-free brine drilling fluid system was formed: brine +(0.1%-0.2%) Na OH +(0.2%-0.4%) HT-XC +(2.0%-3.0%) YLJ-1 +(0.5%-2.0%) SDNR +(1.0%-2.5%) FT-1 A +(1.0%-5.0%) SD-505 + compound salt density regulator. Lab evaluation showed that the fluid had satisfactory temperature resistance(up to 150 ℃), excellent cuttings tolerance(up to 25%), and strong inhibition(92.7% cuttings recovery); Moreover, its lubrication performance was similar to that of all oil-based drilling fluid. The wellbore could be fairly cleaned at annular up-flow velocity of more than 0.8 m/s if the ratio of yield point to plastic viscosity was kept above 0.5. This fluid system has been applied in the drilling of three coiled tubing sidetracking wells in the Liaohe Oilfield, during which the system was stable and easy to adjust, resulting in excellent cuttings transportation, high ROP, regular hole size, and no down hole accidents. In summary, the solids-free brine drilling fluid system can meet the technical requirements of coiled tubing drilling.展开更多
为了揭示盐水对有机盐钻井液性能的影响规律与作用机理,调控和稳定复杂条件下有机盐钻井液的性能,研究了盐水侵污对塔里木油田库区块钻井用有机盐钻井液流变性能和沉降稳定性的影响,分析了盐水侵污机理。结果表明:盐水对现场有机盐钻井...为了揭示盐水对有机盐钻井液性能的影响规律与作用机理,调控和稳定复杂条件下有机盐钻井液的性能,研究了盐水侵污对塔里木油田库区块钻井用有机盐钻井液流变性能和沉降稳定性的影响,分析了盐水侵污机理。结果表明:盐水对现场有机盐钻井液体系的主要作用是稀释,稀释作用导致黏度、切力大幅度下降,泥饼明显增厚,沉降稳定性变差。在40%盐水侵污时,表观黏度由103 m Pa·s降至18.5 m Pa·s;中压失水量、高温高压失水量分别由1 m L、7 m L增至2.7 m L、28.1 m L;中压、高温高压下的滤饼厚度分别由0.5 mm、2 mm增加至1 mm、7mm;钻井液的密度差由20℃、150℃条件的0 g/cm^3、0.18 g/cm^3增至0.08 g/cm^3、0.32 g/cm^3。由盐水侵污引起的有机盐钻井液性能的变化无疑会增加井下复杂情况发生的频率。展开更多
文摘This project is explaining a laboratory development of a solid free drilling fluid formula that could be potentially used in tight gas reservoirs. The configuration of the weak gel fluid WGL-1, which is resistant to high temperature and high salt, was tested, and concluded that its gelling properties, salt and temperature resistance, and environmental protection were all in line with industry requirements. The final drilling fluid formula was developed as: water + (0.3% ~ 0.5%) NaOH + 5% KCl + 2% WGL-1 + 5% NaCl + (1.0% ~ 2.0%) HBFR Anti-high temperature fluid loss agent + 2% Polyol + (1.5% ~ 2.0%) SDL-1 Lubricant + 0.4% A4O1. The performance of the liquid was tested for temperature resistance, inhibition, gas formation protection effect, plugging performance, and static settlement stability. It was concluded that the temperature resistance performance is satisfied at 150°C, and the cuttings recovery rate is as high as 96.78%. It has good performance in inhibiting water dispersion and swelling of cuttings. The permeability recovery value reaches 88.9%, which meets the requirements of gas formation protection. The SSSI value shows that its settlement stability is good;under high temperature and high pressure, its sealing performance is good. This drilling fluid system has achieved the expected results and laid a foundation for further promoting the development of solid-free drilling fluid systems. The future development direction of solid-free drilling fluids is pointed out, to the improvement of properties to be applied in high temperature environment and have high salt resistance capacity.
基金Supported by the China National Science and Technology Major Project(2016ZX05020-004)
文摘There are many problems associated with coiled tubing drilling operations, such as great circulation pressure loss inside pipe, difficulties in weight on bit(WOB) transferring, and high probability of differential sticking. Aiming at these problems, solids-free brine drilling fluid system was developed on the basis of formulation optimization with brine base fluid experiment, which was evaluated and applied to field drilling. Based on the optimization of flow pattern regulator, salt-resisting filtrate reducer, high performance lubricant and bit cleaner, the basic formula of the solids-free brine drilling fluid system was formed: brine +(0.1%-0.2%) Na OH +(0.2%-0.4%) HT-XC +(2.0%-3.0%) YLJ-1 +(0.5%-2.0%) SDNR +(1.0%-2.5%) FT-1 A +(1.0%-5.0%) SD-505 + compound salt density regulator. Lab evaluation showed that the fluid had satisfactory temperature resistance(up to 150 ℃), excellent cuttings tolerance(up to 25%), and strong inhibition(92.7% cuttings recovery); Moreover, its lubrication performance was similar to that of all oil-based drilling fluid. The wellbore could be fairly cleaned at annular up-flow velocity of more than 0.8 m/s if the ratio of yield point to plastic viscosity was kept above 0.5. This fluid system has been applied in the drilling of three coiled tubing sidetracking wells in the Liaohe Oilfield, during which the system was stable and easy to adjust, resulting in excellent cuttings transportation, high ROP, regular hole size, and no down hole accidents. In summary, the solids-free brine drilling fluid system can meet the technical requirements of coiled tubing drilling.
文摘为了揭示盐水对有机盐钻井液性能的影响规律与作用机理,调控和稳定复杂条件下有机盐钻井液的性能,研究了盐水侵污对塔里木油田库区块钻井用有机盐钻井液流变性能和沉降稳定性的影响,分析了盐水侵污机理。结果表明:盐水对现场有机盐钻井液体系的主要作用是稀释,稀释作用导致黏度、切力大幅度下降,泥饼明显增厚,沉降稳定性变差。在40%盐水侵污时,表观黏度由103 m Pa·s降至18.5 m Pa·s;中压失水量、高温高压失水量分别由1 m L、7 m L增至2.7 m L、28.1 m L;中压、高温高压下的滤饼厚度分别由0.5 mm、2 mm增加至1 mm、7mm;钻井液的密度差由20℃、150℃条件的0 g/cm^3、0.18 g/cm^3增至0.08 g/cm^3、0.32 g/cm^3。由盐水侵污引起的有机盐钻井液性能的变化无疑会增加井下复杂情况发生的频率。
