化学就地生热提高注蒸汽井井底干度可行性分析

Feasibility Analysis of Using In-situ Thermal Chemical Heat Generation Method to Improve Bottom-hole Dryness of Steam Injection Wells

蒸汽吞吐开采技术在国内外均有广泛应用,但工艺中存在设备参数难以控制、蒸汽运输过程中热损失大和注蒸汽成本高等缺点,导致注入井底的蒸汽干度大大降低,传递到井底的热量波及面积小,驱油效果差。针对以上问题,依据硝酸钠,氯化铵和尿素在弱酸环境下反应放热的原理,提出一种井底增干剂。该增干剂不仅在井底放出热量,提升井底干度,而且反应产生的无污染气体还能作为驱动力辅助驱油。最后,将此方法应用在实例中,证明了该设计的可行性。

Steam huff and puff has been widely used at home and abroad,but there are some shortcomings in the process,such as the unmanageable equipment parameters,large heat loss in the process of steam transportation and high cost of steam injection. As a result,the dryness of steam injected into the bottom of the well is greatly reduced,the heat conducted to the bottom of the well has a small sweep area,and the oil displacement effect is poor.In view of the above problems,based on the reaction exothermic principle of sodium nitrate,ammonium chloride and urea in weak acid environment,a formulation for improving steam quality is proposed. The designed formulation not only releases heat at the bottom of the well and improves the steam dryness,but also produces non-polluting gas which can be serve as driving force to displace oil. Finally,this method is applied to an example to prove the feasibility of the design.