Research advances on the in-situ pressure-preserved coring and gas parameter determination for deep coal seams
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摘要:
煤层原位瓦斯压力与瓦斯含量是深部煤矿安全生产与煤层气资源精准评估的关键参数。针对深部煤层原位瓦斯含量精准测定的技术难题，提出了原位保压取心与原位瓦斯含量和压力测试的全新原理，推导并建立了煤层原位瓦斯含量计算方法和考虑含水率及多气体组分影响的煤层原位瓦斯压力计算方法。根据矿井深部原位应力环境特点与多向取心工程需求，分别自主研发了重力式、弹力式和磁力式保压控制器，可实现任意角度保真取心。自主研制了集低扰动保压取心与样品含气量一体化测试技术与装备，可实现与保压取心器对接并解锁的原位样品转移、破碎与测试，解决了原位取心、样品转移过程中瓦斯量损失问题，大大提高了瓦斯含量测定的准确性，为精准测定深部煤层原位瓦斯压力及瓦斯含量提供了理论和技术支撑，以期降低瓦斯事故，提高高突矿井安全开采效率。
Abstract:The in-situ gas pressure and content of coal seams are critical for the safe production of deep coal mines and the accurate evaluation of coalbed methane resources. To address the technical challenges of accurately determining in-situ gas content in deep coal seams, this study proposed brand-new principles of in-situ pressure coring and the tests of in-situ gas content and pressure. It also derived a calculation method for in-situ gas content in coal seams and a method for determining the in-situ gas pressure while considering the effects of moisture content and multiple gas components. Given the in-situ stress environment deep in mines and the demand for multi-direction coring, this study introduced independently developed pressure-preserved controllers using gravity, elastic force, and magnetic force. The authors of this study also independently developed a set of technology and equipment that integrates low-disturbance pressure-preserved coring and the gas content tests of samples. This set of technology and equipment allows for in-situ sample transfer, pulverization, and tests that are integrated with the pressure-preserved coring device and can unlock the coring device. This avoids gas escape and loss during in-situ coring and sample transfer, thus significantly improving the accuracy of the gas content determination. This study provides theoretical and technical support for accurately determining in-situ gas pressure and content in deep coal seams, aiming to reduce gas accidents and enhance the mining efficiency of mines with high outburst risks.
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图 2 保压取心器结构原理及实物
Fig. 2 Structural principle and physical object of the pressure-preserved coring device
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图 4 保压煤样全程密闭转移及破碎瓦斯含量测试流程
Fig. 4 Integrated process of the whole-process closed transfer, pulverization and gas content tests of pressure-preserved coal samples
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图 5 保压取心瓦斯压力测定原理
Fig. 5 Schematic of gas pressure determination principle of pressure-preserved coal samples
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图 7 保压取心一体化破碎装置
Fig. 7 Integrated pulverization device for pressure-preserved coal samples
表 1 煤层气、瓦斯含量测定方法对比
Table 1 Comparison of methods for determining coalbed methane and gas contents
测试方法 不同阶段瓦斯量构成 GB/T 23250—2009
煤矿井下瓦斯含量(常压自然解吸法)损失量 井下解吸量 粉碎前解吸量 粉碎后解吸量 不可解吸量 GB/T 23250—2009
煤矿井下瓦斯含量(真空脱气法)损失量 井下解吸量 粉碎前脱气量 粉碎后脱气量 GB/T 23249—2009
地勘时期瓦斯含量采样过程中瓦斯损失量 煤样解吸
量粉碎前脱气量 粉碎后脱气量 GB/T 19559—2021
煤层气含量测定方法损失量 实测的自然解吸量 残余气量 GB/T 28753—2012
煤层气含量测定 加温解吸法损失量 解吸量 残余气量 煤层原位瓦斯含量(保压取心法) 初次解吸量(Q1) 转移解吸量(Q2) 粉碎解吸量(Q3) 不可解吸量(Q4) 
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