钻井式煤炭地下气化技术的发展及关键力学问题

煤炭地下气化技术是有希望解决我国能源危机的重要手段之一,是煤炭资源高效清洁利用的有效手段之一,是拓展天然气资源实现战略资源接替的有效方法之一。本文通过调研国内外煤炭地下气化技术,将煤炭地下气化技术分为两类,即钻井式技术和巷道式技术,并重点叙述了钻井式煤炭地下气化技术开发模式。钻井式煤炭地下气化技术的发展可分为4个阶段:(1)基础理论研究阶段;(2)钻孔式技术开发模式阶段;(3)不同贯通方法直井钻井开发模式阶段;(4)水平井钻井开发模式阶段。本文分别对钻孔式、直井钻井式以及水平井钻井式等3种煤炭地下气化技术开发模式的技术核心进行了论述。通过对比不同技术开发模式的使用状况,对其优劣进行了评价。在总结煤炭地下气化技术开发模式发展历程的基础上,指出了地下煤气化技术的发展趋势,对我国将要到来的煤炭地下气化商业化开发局面有积极的指导意义。

DEVELOPMENT HISTORY AND KEY MECHANICAL PROBLEMS OF WELL DRILLING UNDERGROUND COAL GASFICATION TECHNOLOGY

Underground coal gasification technology is important in the context of China’s energy crisis, for the efficient and clean utilization of coal resources, and for expanding the natural gas resources to realize the strategic resource replacement. Based on the investigation of underground coal gasification technology at home and abroad, this paper divides underground coal gasification technology into two categories, namely drilling technology and roadway technology, and focuses on the development mode of drilling underground coal gasification technology. The technology development of the well drilling UCG can be divided into four stages:(1) the basic theory research stage;(2) the borehole method technology development mode stage;(3) the linked vertical well development mode stage with different channel breakthrough methods;(4) the horizontal well development mode stage. This paper focuses on the key technology of three development modes in the UCG process, including the borehole mode, the vertical well drilling mode and the horizontal well drilling mode. By comparing different uses of these technology modes, the advantages and disadvantages are evaluated in detail.On the basis of summarizing the development process of underground coal gasification technology development mode, this paper points out the development trend of underground coal gasification technology, which has a positive guiding significance for the coming commercial development of underground coal gasification in China.