摘要 |
The process comprises the following operations: - bringing wet material to form a pile 4 so as to allow the water to flow away by percolation over the height of the pile 4 while saturating the material situated in the lower part of the latter and causing free water to appear; - removal of the free water from the lower part of the pile so as to prevent the free water level from rising; - removing drained material from a "withdrawing" level which is sufficiently raised above that of the free water. It is characterised in that the pile 4 being produced on an area 1 for draining water, the part 6 of the pile situated between the draining zone and the withdrawing level, called a passive zone, is employed as a filtering zone used for protecting drains placed in the draining zone and preventing their blocking, this passive zone 6 being reserved for the draining of a number of piles deposited on it successively, before being replaced when it begins to be blocked. <IMAGE> |