六盘水煤层气勘探开发前景分析

ANALYZING THE PROSPECT OF COAL-BED METHANE EXPLORATION AND DEVELOPMENT AT LIUPANSHUI

本文以六盘水煤层气勘探开发试验获得的实际资料为基础 ,结合国内外煤层气勘探开发成果 ,对其勘探开发前景进行了初步研究。指出该区具有煤层多 ,累计厚度大 ,煤阶类型多样 ;煤层含气量较高 ,煤层气资源量丰富 ;含气饱和度、临界解吸压力与地层压力的比值中等 ;煤层渗透性非均质性较强 ;煤层单层较薄 ,煤体结构较差 ;煤层地应力较高 ,杨氏模量较低及地形条件较差等特点。通过对上述特点的综合分析 ,文章认为六盘水煤层气地质特征总体表现为煤层气资源条件优越 ,煤层气可采性较差 ;目前制约煤层气勘探开发的关键技术问题是选层技术、压裂技术和形成井网技术。建议继续六盘水煤层气勘探开发试验 ,并重点开展选层技术。

On the basis of the experimental data, a primary research on the prospect of coal-bed methane exploration and development at Liupanshui is carried out in the paper in combination with the domestic and foreign coal-bed methane exploration and development results. It is pointed out that this region is of these characters, such as there are a large number of coal-beds with a great cumulative thickness and multiple coal rank;methane content in coal-beds is relatively high with abundant methane resources; the gas saturation and the critical desorption pressure-to-formation pressure ratio are middling; the heterogeneity of coal-bed permeability is relatively strong;single coal-bed is thin and the coal body structure is bad;ground stress of the coal-beds is relatively high and young's modulus is low; and topographic conditions are complicated; etc. Through comprehensively analyzing above-mentioned characters, it is thought that the geological characteristics of coal-bed methane at Liupanshui may be summarized as an advantageous coal-bed methane resource condition and a bad coal-bed methane recoverability;and the key techniques restricting coal-bed methane exploration and development at present are horizon-selected techniques, fracturing techniques, and well pattern-formed techniques. Finally, it is suggested to continue the experiment of the coal-bed methane exploration and development at Liupanshui and emphatically to carry out the key research on the horizon-selected, fracturing and well pattern-formed, techniques.