天然气水合物注热开采能量分析

天然气水合物储量巨大、清洁环保，作为一种潜在战略能源逐渐受到了重视。综述了天然气水合物开采方式并进行了分析，认为由于水合物以固体形式存在，原始状态下渗透率极低，压力传播范围十分有限，降压法开采面临一定的困难；考虑了加热法开采水合物过程中地层内的所有吸热因素，把水合物加热分解过程分为了三个阶段；计算了各部分吸收热量占注入热量的比例。结果表明：注热开采水合物的大部分能量被非水合物升温所消耗，因此提供足够的热源是水合物开发的关键。针对海底水合物开采所需要大量能量供给的状况提出了两种经济廉价的热源。

THERMAL ANALYSIS ON HEAT INJECTION TO NATURAL GAS HYDRATE (NGH) RECOVERY

Natural gas hydrate (NGH) is a clean alternative energy with huge reserves which has been thought highly by energy explores in the world. Through analysis on many NGH recovery methods, this study thought the depressurizing method was not proper because NGH was in solid with extremely low permeability in its original state; whereas the heat injection method was the first choice to extract NGH. This study divided the course of NGH being heated and decomposed into three stages in consideration of all the factors involving heat absorption in the formations during the whole process of the heat injection method, and then calculated the proportion between heat absorption and the total injected heat in each stage. The study results showed that a majority of thermal analysis was consumed by the increasing temperature of non NGH and so it was essential to supply enough heat to extract NGH. Hereby two cheap and cost effective heat sources were introduced to solve the problem of heat source supply.