Freshwater costs of seawater desalination: Systems process analysis for the case plant in China

Abstract

Seawater desalination is one of the most essential strategies to solve freshwater shortage issues worldwide. Though having the possibility of providing abundant freshwater resources, desalination projects are also limited by the pressure of freshwater consumption. Based on the systems process analysis, the freshwater cost of seawater desalination is assessed with the case study of a 25,000 tons/day seawater desalination plant in Huanghua Port, Hebei Province, China. The total embodied water consumption is 9.02E+06 m3, which is estimated in magnitude as five percent of the total freshwater production in the design cycle. Among all the sub-projects, the embodied water consumption in the technology system engineering represents the largest component, accounting for 60.12% of the total. The productivity level of the project is calculated to be 19.29, which highlights the potential of the desalination project for alleviating the shortage of freshwater. It is necessary to notice that the water yield of the project is calculated to be 9.12E+06 m3, which could achieve the freshwater balance of the construction phase in the first year of operation. The comprehensive inventory and procedure of the embodied water accounting in this work are expected to provide useful references for rational allocation of water resources and optimal design for other desalination projects.