PROCESS FOR PRODUCING HIGH-PURITY WATER FROM LOW-PURITY WATER AND APPARATUS FOR PRODUCING THE HIGH-PURITY WATER

摘要

Based on the findings from the investigation of technical problems in obtaining fresh water from gas hydrates using seawater, the method for producing high-purity water from low-purity water according to the invention solves the above problems. In order to obtain high-purity water from low-purity water, which is not limited to seawater but includes sewage, the method includes the steps of: having one or more types of gases capable of forming gas hydrates and low-purity water come into contact under conditions in which the temperature is higher than the freezing point of the low-purity water and the gas hydrates can be formed, thereby producing solid gas hydrates which are suspended in the low-purity water; removing the low-purity water used in the gas hydrate formation process while substantially maintaining the gas hydrate state, and rinsing off components adhered to the gas hydrates with rinsing water; and by increasing the temperature in the gas hydrate state or decreasing the pressure in the gas hydrate state, decomposing the gas hydrates into a gas and high-purity water. These steps are carried out in the above order.