煤矿矿井水“零排放”与全资源化利用模式的技术经济分析——以后安煤矿为例

Technical and Economic Analysis of “Zero Discharge” and Full Resource Utilization Mode of Coal Mine Water—Taking Hou’an Coal Mine as an Example

摘要: 为解决我国煤矿矿井水资源化利用率偏低、经济性评估体系不健全的突出难题，本文以后安煤矿为工程依托，构建了“预沉淀–超滤–反渗透双膜法深度净化–全资源化回用”一体化零排放技术体系，并建立了覆盖项目全生命周期的技术经济分析模型。工程应用结果表明，该系统设计处理规模为5500 m³/d，进水悬浮物浓度介于500~3000 mg/L，处理后出水水质达到《国家生活饮用水卫生标准》(GB 5749-2022)，实现矿井水100%资源化回用；项目年回用水量达181.5万立方米，年回收煤泥1.2万吨，通过空压机余热回收可替代燃煤730吨，资源回收效益显著。经济评价结果显示，该项目总投资7000万元，年均总收益3459万元，年运行成本369万元，年净收益3090万元，静态投资回收期2.26年，内部收益率44.1%，净现值(折现率8%)达1.83亿元，经济效益可观。敏感性分析结果表明，水价与电价是影响项目经济性的最敏感因素，而药剂费用与膜组件使用寿命对项目效益的影响相对较小。此外，该项目还能有效减少水资源浪费与污染物排放，具有显著的环境效益和社会效益。本研究构建的技术体系与经济分析模型，为我国煤矿矿井水零排放与全资源化利用提供了可量化、可复制、可推广的技术经济参考范式。

Abstract: To solve the prominent problems of low resource utilization rate and imperfect economic evaluation system of coal mine water in China, this paper takes Hou’an Coal Mine as the engineering support, constructs an integrated zero-discharge technology system of “pre-sedimentation - ultrafiltration - reverse osmosis dual-membrane advanced purification - full resource reuse”, and establishes a technical and economic analysis model covering the whole life cycle of the project. The results of engineering application show that the designed treatment capacity of the system is 5500 m³/d, the influent suspended solids concentration ranges from 500 to 3000 mg/L, and the treated effluent quality meets the National Sanitary Standards for Drinking Water (GB 5749-2022), realizing 100% resource reuse of mine water; the annual reused water volume of the project reaches 1.815 million cubic meters, the annual recovered coal slime is 12,000 tons, and 730 tons of coal can be replaced by waste heat recovery from air compressors, with significant resource recovery benefits. The results of economic evaluation show that the total investment of the project is 70 million yuan, the average annual total benefit is 34.59 million yuan, the annual operation cost is 3.69 million yuan, the annual net benefit is 30.90 million yuan, the static investment payback period is 2.26 years, the internal rate of return is 44.1%, and the net present value (discount rate 8%) reaches 183 million yuan, with considerable economic benefits. Sensitivity analysis results indicate that water price and electricity price are the most sensitive factors affecting the project economy, while the impact of chemical agent cost and membrane module service life on project benefits is relatively small. In addition, the project can effectively reduce water waste and pollutant emissions, and has significant environmental and social benefits. The technical system and economic analysis model constructed in this study provide a quantifiable, replicable and promotable technical and economic reference paradigm for the zero discharge and full resource utilization of coal mine water in China.