Prof. ZHANG Hongxun, Associate Prof. YU zhisheng and LIU Xinchun are responsible for this project funded by the national science and technology major projects. This work presents the first demonstration project in China for treatment of coal-bed methane (CBM) produced water and recycling to provide a research and innovation base for solving the pollution problem of CBM extraction water. The below is on-site photograph of the pilot-scale demonstration with reverse osmosis unit.

The total dissolved solids (TDS) in the CBM produced water are removed to meet the "drinking water standards" and "groundwater quality standards" of China and can be used as drinking water, irrigation water, and livestock watering. The cost for treatment of CBM produced water is also assessed, and the RO technology is an efficient and cost-effective treatment method to remove pollutants.

Furthermore, a model for the RO membrane separation process is developed to describe the quantitative relationship between key physical quantities - membrane length, flow velocity, salt concentration, driving pressure and water recovery rate, and the water recovery restriction equation based on mass balance is developed. This model provides a theoretical support for the RO system design and optimization.