RAW WATER TREATMENT DEVICE

PURPOSE:To introduce raw water into a sedimentation part properly according to increase in size of adhesive carriers by flowing raw water such as bilge water of ship containing microorganisms and oil content and mixing it with water containing granular adhesive carriers to purify the water by its fluidization and sedimentation. CONSTITUTION:In a raw water treatment device, raw water from a raw water flow-in part 4 is mixed with water containing adhesive carriers (f) in a container 1, and the mixed fluid raised along an air lift part together with air injected from an air tube 2 is lowered at a flow part A. A sedimentation part B connected to the flow part A through a connecting port 5a is separated from the flow part A by a partition 5, and the partition 5 is raised and lowered by lifting mechanisms 9 to 11 for the partition 5 to adjust the opening of the connecting port 5a. When the adhesive carriers (f) become large, the connecting port 5a is increased in diameter to reduce the flowing velocity of it, thus separating the adhesive carriers (f) from each other. When they are oscillated, the connecting port 5a is reduced in diameter to suppress the oscillation of the carriers in the flow part A from being[propagated to the sedimentation part B.