潘河15号煤层煤层气的生产特征及其影响因素分析

为了掌握潘河区块15号煤层煤层气的生产动态特征,确定影响产能释放的主要因素,实现区域内产气量的平稳接替和潘河区块煤层气的稳定有序开发,本文以潘河区块所实施的15号煤层煤层气试验井为研究对象,统计分析了生产动态参数,全面研究了排采过程中的产水、产气和产煤粉的变化趋势和特征以其影响因素。研究结果表明：15号煤煤层气储层具有产水量低、高产气井少、煤粉产出量大的特点,产水和煤粉量对产气量有明显的抑制作用；区内煤层气井适宜部署在煤层气保存较好的包括背斜等构造高点及斜坡,且含气量超过20m_³/d,水动力条件弱的滞留水区；施工液量对压裂效果影响较大,尤其是造缝功能的前置液,在压裂正常情况下以及前置液量在110-210m_³范围内,液量和产气量同步变化；在排采过程中,排采初期的降液速度、见气初期的控制以及排采的连续性是影响区内煤层气井产能释放的主要原因。

Analysis on Production Performance and its Influencing Factors of No.15 Coal Seam in the Panhe CBM Gas Filed

In order to obtain the production dynamic characteristics of No.15 Coal Seam in the Panhe CBM Gas Filed, identify the main factors affecting its productivity and achieve the its stable development, this paper took the coal bed gas test wells of No.15 Coal Seam as research object, analysed the production performance of these wells and investigated the water production, gas yield, pulverized coal production and their influencing factors. The results show that the No.15 Coal Seam in the Panhe CBM Gas Filed is characterized by low water production, lack of high gas yield well and high pulverized coal production, the water production and pulverized coal significantly reduce the gas yield; the coalbed gas well should take precedence to be arranged in upper bend and high point of structure where gas content should exceed 20m_³/t and areas belong to weaker hydrodynamics; fracturing effect is greatly affected fracturing fluid quantity, especially prepad fluid for producing gaps, prepad fluid quantity synchronously changes with gas yield when prepad fluid quantity ranges from 110m_³ to 210m_³; pressure decay rate, initial control when gas appearance and drainage continuity are main reasons influencing gas yield in the process of drainage gas recovery.