GRANULAR MEDIUM USED IN FLUIDIZED BED TYPE WATER PURIFYING APPARATUS AND WATER PURIFYING METHOD

摘要

PURPOSE:To effectively perform the removal of residual chlorine in water and the rising of pH to a neutral region by using a granular medium consisting of a linear ethylene/alpha-olefin copolymer and cristobalite. CONSTITUTION:A granular medium 2 with density of 1.04-1.65g/ml is prepared by compounding 100 pts.wt. of a linear ethylene/alpha-olefin copolymer with density of 0.910g/ml or less prepared according to a gaseous phase low pressure method and 20-250 pts.wt. of cristobalite. Waste water containing various contaminants is sent to an upper chamber 1D from a waste water supply port 1G and passed through a net 1B while agitated by barrier plates 1J arranged over a proper number of stages to flow down to a granular medium receiving chamber 1E having the granular medium 2 received therein. Herein, the granular medium 2 forms a fluidized state by the flowing down waste water and the air from an air pipe 1N and the contaminants in the waste water are adsorbed on the granular medium to be grown into coarse particles. These adsorbed grown contaminant particles are released from the granular medium 2 because the granular medium 2 is agitated in a fluidized state.