Baotou Coal Chemical High-Salt Wastewater Salt Separation & Crystallization Unit

Owner: Guoneng Baotou Coal Chemical Co., Ltd. Location: Baotou, Inner Mongolia. The unit is a supervised project of the Ministry of Ecology and Environment, the Inner Mongolia Autonomous Region and Baotou City, approved in July 2019 and commissioned in November 2021. Designed to treat 4 million m³ of high-salt effluent per year, it recovers 3.3 million m³ of product water plus 15,300 t of industrial sodium chloride and 17,000 t of industrial sodium sulphate annually, using pre-treatment, membrane concentration, nanofiltration salt separation, freeze crystallisation for sulphate removal and evaporation crystallisation. Salt products reached 98.7% (NaCl) and 99.1% (Na₂SO₄) purity, above the respective first-grade specifications for coal-chemical by-product salts. The unit ran continuously for 754 days as of 20 September 2023. Source: CNR (25 Dec 2023). Image: Aerial view of the high-salt wastewater salt-crystallisation unit (photo: Guoneng Baotou Coal Chemical)