Study On Transportation And Desalination By Centrifugation Of Sea Ice

Water resources shortage is a hot potato that badly restricts the economic development in the areas around the Bohai Sea. Finding a new fresh water resources to resolve the water shortage problem is an very important task for our researchers. In recent years, some tentative plans have been provided for using the sea ice resources which was a disaster in the people's impression to transform into the fresh water resources. Sea ice is studed from the point of view resources, which provide a new path to resolve the water shortage problem in the areas around the Bohai Sea.Based on the Eleventh Five-Year Plan—Study on the Key Techonogy & Experiment of Using Bohai Sea Ice Resources, equipments of the sea ice transportation by straps and waterpower were designed and made, and some locale experiments were conducted. The ability of the sea ice transportation of the two methods was measured, and the cost of the sea ice transportation was calculated. The experimental results show that two methods of the sea ice transportation can transport it effectively, and the cost of its transportation by waterpower is 0.323yuan/m3, which is lower than that of the transportation by straps(0.495yuan/m3).Desalination by centrifugation of sea ice is presented. The effect of factors in the centrifugal desalination process on sea ice's salinity, concentrations of Ca2+ and Mg2+ were studied, which contained the centrifugal speed, the centrifugal time, the ambient temperature, the diameter of particles and so on. The experimental results show that sea ice's salinity , concentrations of Ca2+ and Mg2+ are reduced when the centrifugal speed is increased and the centrifugal time is prolonged. Higher ambient temperature makes for the removal of salt , Ca2+ and Mg2+, but it results in higher loss ratio of sea ice. Diameter of particles has an effect on the salt removal efficiency, and they are too small to desalt perfectly. When the ambient temperature is -2℃, the centrifugal time is 12min and the centrifugal speed is 2000rpm, the salt rejection of sea ice is 72.80%, the salinity is below 1‰, and the ratio loss of sea ice is 16.28% at that time.In addition, desalination by centrifugation using different salinity water to spray washing sea ice was also studied in this paper. Using lower salinity water to spray washing sea ice in the process of centrifugal desalination has an obvious effect on the sea ice's desalination. If using higher salinity water to spray washing sea ice, it has disadvantage of its desalination.