地热外围回灌优化开发方案的研究

THE STUDY ON OPTIMAL EXPLOITATION SCENARIO OF REINJECTION AROUND PERIPHERY OF GEOTHERMAL ZONE

根据地质构造特征和地热资源评价,针对目前在资源开采阶段补建回灌井所面临的问题(包括断裂构造对热储层发育、地热流体径流补给通道等因素的影响以及地理位置的限定),提出了在中心采区外围实施回灌的新思路。结合不同采灌模式,对压力场和温度场的变化特征及影响程度分别进行分析。从分析结果可知,外围回灌将会较好的控制中心采区水位下降速率,延长热突破时间,最大限度地挖掘热储潜力,还可解决在中心采区补建回灌井空间位置不足的问题。

Based on general characteristics of the reservoir, the supposition of the reservoir modeling, and the problem of no more space for adding reinjection wells, the mathematical descriptions and influent of hydra-thermal transportation, convection, thermal break-through, and the flow feed path with the different fracture zone were emphasied. According to simulation of the different models, a new ideal about the reinjection wells was put forward, which can be set in the periphery of geothermal zone. And more heat can be extracted from the reservoir rocks through the reinjection activities. The pressure and temperature field of the reservoir will be controlled even though the injected cool water moves forward to the product zone, the water level and temperature field can be more stable with the reinjection models.