| 摘要 |
PROBLEM TO BE SOLVED: To perform surface cutting of a coarse-grained fraction by a very simple arrangement in which general-purpose and cheap price instrument and material are used, cleaning efficiency is raised, and small scale making of a cleaning plant and reduction of a cleaning cost are contributed.SOLUTION: In a cleaning method, a slurry (a) in which an earth that is contaminated by a harmful matter and water are mixed is put in a container 1, the slurry (a) in the container 1 is circulated among the container 1, a pump 2, and transport piping 3, circulation of the slurry (a) is repeated by continuous running of the pump 2, and a coarse-grained fraction b of the earth is taken out by classification from the slurry (a) after circulation for a prescribed time, and the coarse-grained fraction b is obtained in which concentration of the harmful matter has become lower concentration comparing with that of the original earth. |
