瓦斯含量直接法测定技术在寺河矿的应用研究

近年随着采掘深度的延深,煤矿瓦斯灾害风险也越来越高。本文以寺河矿东井为例,应用瓦斯含量直接法,建立了在井下随钻随测煤的可解吸瓦斯量的方法、工艺及测定装置。结合煤在标准大气压力下的残存瓦斯含量的确定,认为无烟煤巷道瓦斯排放带宽度大约为10m,瓦斯含量随深度增加而增大,大约在20m以后,瓦斯含量变化不大,接近煤层瓦斯含量。

先进的MWD／LWD测量系统

在创世界记录的西江２４－３－Ａ１４大位移井中，ＭＷＤ／ＬＷＤ测量系统起到了关键性的作用《Ａｎａｄｒｉｌｌ的Ｍ１０型ＭＷＤ具有精度高，传输采用正弦波连续脉冲方式，传输速度快。ＬＷＤ随钻测井系统和ＣＤＲ和ＣＤＮ测井工具，实时测量井径伽马、电阻率、中子密度、孔隙度４条测井曲线。文中主要介绍了ＭＷＤ／ＬＷＤ的工作原理、脉冲传输方式及在该井的应用情况。

应用录井资料求地应力剖面

该文介绍了应用录井资料求连续地应力剖面的方法,该方法以钻井理论为基础、通过计算岩石抗压强度及内摩擦角求出地应力剖面。在大庆油田两口井共56层,与测井法求出的地应力对比,平均相对误差6.8%。这种方法的特点是成本最低,随钻随测,连续测量。

An equivalent-tool theory for acoustic logging and applications

The influence of an acoustic logging tool on borehole guided wave propagation should be considered in the processing and inversion of the guided waves for formation acoustic property estimation. This study introduces an equivalent-tool theory that models the tool response using an elastic rod with an effective modulus and applies the theory to multipole acoustic logging for both wireline and logging while drilling （LWD） conditions. The theory can be derived by matching the tool’s acoustic impedance/conductance to that of the multipole acoustic wavefield around the tool, assuming that tool radius is small compared to wavelength. We have validated the effectiveness and accuracy of the theory using numerical modeling and its practicality using field data. In field data applications, one can calibrate the tool parameters by fitting the theoretical dispersion curve to field data without having to consider the actual tool’s structure and composition. We use a dispersion correction example to demonstrate an application of the simple theory to field data processing and the validity of the processing result.

煤层瓦斯原位探测仪在测定煤层瓦斯压力的应用

煤层瓦斯压力是评价煤层突出危险性与计算煤层瓦斯含量的一个重要指标。传统被动式测压测试数据准确,比较接近原始储层压力,但是存在测试时间长、测试仪器的不可重复使用性的不足。煤层瓦斯原位探测仪由水力密封装置、探测与存储装置和自动取样装置3部分组成。利用该仪器能够在钻孔中做到随钻随测,且具有可重复性使用的特点,不仅可准确测得某一深度的煤层瓦斯压力,记录压力随时间的具体变化,节省了测试时间和人力物力,在煤层瓦斯测压方面具有推广价值。