陕北某气田闪蒸分液罐结垢原因分析及处理措施研究

REASON AND TREATMENT MEASURES FOR THE SCALING OF FLASH POINT LIQUID TANK IN A GAS FIELD IN THE NORTH OF SHAANXI PROVINCE

针对陕北某气田闪蒸分液罐结垢严重,通过分析站内天然气组成、污水水质、污水配伍性、结垢产物组成和运行工况等,分析结垢原因并提出相应的处理措施。结果表明,结垢产物主要为Ca CO3,污水中成垢离子含量高、污水不配伍、闪蒸分液罐中存在压力骤降,使得系统中容易产生Ca CO3垢。因此污水不配伍,压力骤降引起CO2分压降低促进Ca CO3结垢是闪蒸分液罐结垢的主要原因。将阻垢剂加药点移至计量分离器出口,实施后,防垢效果显著。

For the serious scaling of a gas field flash point liquid tank in the north of Shaanxi Province, the scaling mason was studied by analyzing on the composition of natural gas, water quality of sewage, compatibility of sewage, composition of scaling products and running condition, and the corresponding treatment measures were put forward. The results showed that the main sealing product was CaCO3; CaCO3 scale was easy to produce because of the high eoneent of sealing ion in water, no compatibility of sewage, and sharp pressure decease in the flash point liquid tank. Hence, the main sealing reason was that, water was not compatible and pressure decreased sharply caused by the CO2 partial pressure reducing which promoted CaCO3 scale in the flash point liquid tank. The results showed that, when dosing point of scale inhibitor was moved to metering separator outlet, the efficiency of scale removal was obvious.