Advanced Water Technology Center (AQWATEC), Environmental Science & Engineering Division, Colorado School of Mines, Golden, Colorado 80401-1887, USA.
Environ Sci Technol. 2011 Sep 15;45(18):7655-63. doi: 10.1021/es201021n. Epub 2011 Aug 17.
Coalbed methane (CBM) or coalbed natural gas (CBNG) is an unconventional natural gas resource with large reserves in the United States (US) and worldwide. Production is limited by challenges in the management of large volumes of produced water. Due to salinity of CBM produced water, it is commonly reinjected into the subsurface for disposal. Utilization of this nontraditional water source is hindered by limited knowledge of water quality. A composite geochemical database was created with 3255 CBM wellhead entries, covering four basins in the Rocky Mountain region, and resulting in information on 64 parameters and constituents. Database water composition is dominated by sodium bicarbonate and sodium chloride type waters with total dissolved solids concentrations of 150 to 39,260 mg/L. Constituents commonly exceeding standards for drinking, livestock, and irrigation water applications were total dissolved solids (TDS), sodium adsorption ratio (SAR), temperature, iron, and fluoride. Chemical trends in the basins are linked to the type of coal deposits, the rank of the coal deposits, and the proximity of the well to fresh water recharge. These water composition trends based on basin geology, hydrogeology, and methane generation pathway are relevant to predicting water quality compositions for beneficial use applications in CBM-producing basins worldwide.
煤层气（CBM）或煤层天然气（CBNG）是一种非常规天然气资源，在美国（美国）和全球范围内储量巨大。由于煤层气产出水的含盐量高，其产量受到大量产出水管理的挑战的限制。通常将其回注到地下进行处理。由于对水质的了解有限，这种非传统水源的利用受到阻碍。创建了一个包含 3255 个煤层气井口数据的综合地球化学数据库，涵盖了落基山脉地区的四个盆地，提供了 64 个参数和成分的信息。数据库中的水组成主要为碳酸氢钠和氯化钠型水，总溶解固体浓度为 150 至 39260mg/L。总溶解固体（TDS）、钠吸附比（SAR）、温度、铁和氟化物等常见成分超过饮用水、牲畜和灌溉用水标准。盆地中的化学趋势与煤储层类型、煤储层等级以及井与淡水补给的接近程度有关。这些基于盆地地质、水文地质和甲烷生成途径的水质组成趋势，与预测全球产煤层气盆地中有益用途的水质组成有关。
