基于浅池理论的硫酸钡垢定点除垢实验研究

Experimental Study on Fixed Point Descaling of Barium Sulfate Scale Based on Shallow Pool Theory

为有效防止油田开采过程中硫酸钡结垢造成的管线及设备堵塞,克服超声波、磁场及高频电场等物理防垢方法的不足,根据浅池理论,研制了具有混合区、结垢区和缓冲区的物理法定点除垢装置。除垢器框架为立方体,结垢板为平板,卡条支撑板具有45°、60°及90°三种角度。用电感耦合等离子体发射光谱仪(ICP)检测除垢装置出口端离子浓度,避免了人为误差。通过除垢装置研究了反应时间、成垢离子初始浓度及温度对硫酸钡结垢率的影响。结果表明,定点除垢器对硫酸钡的除垢效果良好,结垢率约99.9%。反应时间、Ba^(2+)与SO_4^(2-)初始浓度对硫酸钡结垢率的影响较小。5~10 min为定点除垢器内硫酸钡最佳结垢时间。硫酸钡结垢率随温度升高先增加后略有降低,最佳结垢温度为50℃。Ba2+质量浓度为742 mg/L、Ba^(2+)与SO_4^(2-)摩尔浓度比为1∶4时,硫酸钡结垢率可达99.99%。

In order to effectively prevent the plugging of pipeline and equipment caused by barium sulfate scaling in the process of oil field exploitation, and overcome the shortcomings of physical anti-scaling methods such as ultrasonic wave, magnetic field, and high-frequency electric field. According to the shallow pool theory, a physical fixed point descaling device containing mixing zone, scaling area and buffer zone was developed. The descaler frame was a cube, the scale plate was fiat, and the clamping plate had three angles of 45°, 60°, and 90°. Inductively coupled plasma emission spectrometer （ICP） was used to detect ion concentration at the outlet of descaling device, avoiding human errors. The influence of reaction time, initial concentration of fouling ion and temperature on the scaling rate of barium sulfate was studied by the descaling device. The results showed that the descaling effect of fixed-point descaling device was good and the scaling rate was about 99.9%. Reaction time, initial concentration of Ba^2＋ and SO4^2- had little effect on the scaling rate of barium sulfate. 5--10 rain was the best scaling time for barium sulfate in the fixed-point descaling device. The scaling rate of barium sulfate increased first and then decreased slightly with increasing temperature. The best scaling temperature was 50℃. When the mass concentration of Ba^2＋ was 742 mg/L and the molar ratio of Ba^2＋ to SO4^2- was 1：4, the scaling rate of barium sulfate could reach 99.99%.