In October 2020, the Department of Marine Strategic Planning and Economics of the Ministry of Natural Resources released the “2019 National Seawater Report”. The report provides information on seawater utilization in China in 2019, including seawater desalination, direct utilization of seawater and utilization of seawater chemical resources. The figures in the report are statistics excluding Hong Kong, Macau and Taiwan. The summary of the report is as following.
- Scale: By the end of 2019, the daily desalination volume by a total of 115 desalination plants across the country reached 1,573,760 tons per day. Among them, the daily desalination volume by the 17 new desalination plants built in 2019 is 399,055 tons.
- Regional distribution and applications: By the end of 2019, the national desalination plants are distributed in 9 water resource insufficient cities and islands. They are Liaoning, Tianjin, Hebei, Shandong, Jiangsu, Zhejiang, Fujian, Guangdong and Hainan province.
- Technology Used: The number of plants using reverse osmosis membrane technology increased by 12 to 97, accounting for 63.60% of the total number of plants. The number of plants using the low temperature multi effect distillation technology, reverse osmosis membrane technology plus low temperature multi effect distillation technology, and electrodialysis technology also increased.
Direct Utilization of Seawater
- Scale: By the end of 2019, the amount of seawater used as cooling water per year was 148.613 billion tons, increased by 9.457 billion tons from the previous year.
- Regional Distribution: By the end of 2019, it was distributed in 11 provinces (direct-administered municipalities) of Liaoning, Tianjin, Hebei, Shandong, Jiangsu, Shanghai, Zhejiang, Fujian, Guangdong, Guangxi and Hainan.
- Technology Used: The seawater direct-current cooling technology has been developed in China. It is mainly used in power generation, petrochemical industry, iron and steel industry and other industries in coastal areas. By the end of 2019, there are 22 plants using seawater circulation cooling technology.
Utilization of Seawater Chemical Resources
In 2019, products of the utilization of seawater chemical resources, exclude salt, there are bromine, potassium chloride, magnesium chloride, magnesium sulfate and potassium sulfate also be included. The production enterprises are mainly distributed in Tianjin, Hebei, Shandong, Fujian and Hainan provinces.
With regard to the comprehensive utilization of concentrated seawater, the development of technology for product high value-added and industrialization, the Ministry of Natural Resources carried out the first equipment technical renovation at one bromine plant of Tianjin Changlu Hangu Saltern Co., LTD in February 2019, achieving a 10% reduction in energy consumption and an 8% increase in recycle rate, building a model for technology popularization.
The full text can be found from the link below (in Simplified Chinese):