| abstract |
(57) [Summary] [Problem] To reduce the amount of waste mud generated, To provide a muddy water propulsion method that can significantly reduce the amount and cost of disposing of industrial waste. A muddy propulsion method in which excavation is performed while sending muddy water 2 to a face portion of a propulsion device 1 and excavated earth and sand is discharged as muddy water 3 and the muddy water 3 is circulated and used as muddy water 2 for excavation. In the above, by adding the dispersant 7 to the drilling mud 2 used for circulation, the viscosity of the drilling mud 2 is reduced, and the specific gravity of the drilling mud 2 is controlled to a high specific gravity region of 1.2 to 1.4. To do. |