中21井泡沫排水技术研究及效果评价

泡沫排水是排出井内积液、提高气井产量、延长气井开采周期的最经济有效方法之一。随着中21井产气量的降低，气井带液能力下降，当产量降到1.8×10⁴m³/d时，较低的气产量不足以将气井产出的液体完全带出地面，致使井筒内产生积液，生产状况不断恶化，甚至水淹关井，故需要实施泡排作业。对不同种类的含水气井需采用不同类型的起泡剂，中21井含有较高的H₂S和凝析油，因此必须使用含缓蚀剂或兼具缓蚀剂功能的起泡剂，同时需要使用破乳剂处理泡排时产生的乳液。通过对中21井泡排防腐及破乳配套技术的研究，确定了适合于该井起泡性、耐温性、抗油性、缓蚀性均很好的TSY5-7A缓蚀起泡剂和破乳效果好、破乳速度快、油水分离彻底的CT1-12C破乳剂，取得了很好的现场试验效果，使该井维持正常生产。同时形成了一套适合于含H₂S、含油气水井泡排的配套工艺，可解决类似井的排液难题

RESEARCH ON FOAM DEWATERING APPLICATION ON WELL ZHONG 21 AND EFFECTS EVALUATION

Foam dewatering technology is one of the most cost effective methods that remove the accumulative liquid in well, increase the gas yield and prolong the production periods of gas wells. With the declination of gas production on Well Zhong 21, well dewatering ability reduces.  When the production dropped to 1.8×104m3/d, the gas produced could no longer carry the produced water to surface in full quantity and resulted in liquid accumulation in well bore and finally well shutdown. Therefore, form dewatering operation was conducted. Foaming agent varies with different types of water containing gas wells. Since Well Zhong 21 contains much H2S and condensate oil, foaming agent with corrosion inhibitor addictive or with anti corrosion property should be selected. On the other hand, de emulsion agent was needed to treat emulsion produced during dewatering operation. Based on study on foam dewatering, anticorrosion and de emulsion matching technology, TSY5-7A anticorrosion foaming agent that is good in foaming, temperature resistance, anti condensate and anti corrosion, and CT1-12C de emulsion agent that demulsifies effectively and quickly and separates the oil from the emulsion thoroughly, were selected for Well Zhong 21. Good results were achieved of the operation and the normal production of Well Zhong 21 was restored.  Moreover, the dewatering technology that suits for gas well containing H2S and condensate oil was developed thereof and can be applied for the gas wells with similar dewatering problem.