Water systems integration and optimization of methanol production

For the actual situation that a methanol enterprise locating in Qinghai where is known for water shortage and high salty raw water, the water pinch theory was applied and the total salt content was selected as the key pollutant. Through analyzing the current water use within the company, the bottlenecks was identified, followed by setting the minimum water consumption and minimum emissions as the objective function to integrate and optimize the methanol production process. After the optimization process, the direct reuse network saved raw water use by 52.4% and reduced the emissions by 14.7 t/h; the reclamation reuse network saved raw water use by 74% and reduced the emissions by 19.95 t/h. The results could serve as theoretical reference for the water conservation and wastewater reduction in methanol enterprises.