To provide a method of removing organic matter in a removed submarine sludge containing an organotin compound, which is carried out at the same time when the high-water-content dredged soil containing the organotin compound is separated into surplus water and earth and sand and the organotin compound is removed from each of the separated surplus water and the separated earth and sand.
This method includes a step to convey the high-water-content dredged soil containing the organotin compound to a flocculating/settling basin 5, a step to add a flocculant to the basin 5, agitate the dredged soil with the added flocculant and separate the dredged soil into earth and sand, flock-settled sediments and seawater, a filtration step to supply the separated seawater and floating flocks to a sand filtration tank and an activated carbon adsorption tank 9 and remove the suspended matter and the organotin compound contained in the separated seawater, a step to withdraw the earth and sand and the flock-settled sediments from the basin 5 and dry them, and further, a step to stick the organotin compound in the floating flocks of a fixed amount of the organotin compound contained in the dredged soil to a polyethylene sheet 7, which is carried out before the filtration step.
OSHIMA YUJI
OMOTO TERUNORI
HONJO TSUNEO
OMOTO TERUNORI
OISHI KENSETSU KK
KITAGUNI SEIJIRO
HAKATAKO KANRI KK
SUDA KENSETSU KOGYO KK
KINJO RUBBER CO LTD
SHIN NIHON KANKYO KEISOKU KK
AQUA TEIPPEN KK
Shuichiro Ariyoshi