| 摘要 |
PROBLEM TO BE SOLVED: To provide a technology capable of enhancing separation accuracy when separating sand by making raw water including the sand flow to a spiral flow passage.SOLUTION: A sedimentation separation apparatus 1 has the spiral flow passage 4 for making the raw water including the sand flow and a slit formed on the flow passage side of the spiral flow passage 4, and has a separation tank 2 for dropping and separating a part of the sand included in the raw water flowing in the spiral flow passage 4 from the slit, and a plurality of opening parts 15-17 are formed in an upper plate 13 of the separation tank 2, and an introduction position for introducing the raw water into the spiral flow passage 4 is changeably constituted in the length direction of the spiral flow passage 4 by installing an introducing unit 21 in any opening part. |
