| Taking the Bohai Bay as an example, using MIKE3 FM numerical simulation software, a three-dimensional numerical model of temperature and salinity diffusion in the mixed discharge of concentrated seawater from seawater desalination and thermal-discharge from power plants to the sea near Tianjin Port in the Bohai Bay was established, comparative study on the diffusion of temperature and salinity with different mixing ratios of concentrated seawater and thermal-discharge. The result show that the mixed discharge of concentrated seawater and thermal-discharge can significantly reduce the range of salinity rise area in the receiving sea , and the higher the mixing ratio, the more obvious the effect. In terms of temperature rise, compared with the same amount of thermal-discharge separately, mixed discharge will increase the envelope area of temperature rise in the bottom sea area and reduce the surface area, but when the mixing ratio exceeds 1:30 (the thermal-discharge displacement is approximately 35 m3/s), the temperature rise envelope area of the surface and bottom sea areas is close to the temperature rise envelope area of the same amount of thermal-discharge separately; comprehensive consideration of temperature and salinity diffusion, when the discharge of concentrated seawater from seawater desalination is 10×104 m3/d, and the salinity rise does not exceed 20, the mixed discharge ratio with thermal-discharge exceeding 1:30 (the thermal-discharge displacement exceeds 35 m3/s), the salinity can be diluted to the background value near the outfall, and the temperature drop caused by changes in mixed density can be almost negligible. The relevant research conclusions can provide technical support for the scientific discharge of concentrated seawater from seawater desalination, promoting the harmonious and sustainable development of seawater desalination and marine environment. |
