Abstract: The present invention makes it possible to simplify the work of maintaining the covering performance of a covering layer by a method for maintaining a floor covering layer whereby the covering performance of a covering layer B that is formed on a floor (A) and covers the floor (A) can be maintained. In this method, the resin covering layer B having a thickness (T0) of 30 to 100 ?m is formed on the floor. The surface of the resin covering layer B is subjected to dry grinding without the use of a liquid by using grinding pads (6) and (7) provided with grinding surfaces (6a) and (7a) that move along one direction. The generated grindings are recovered, and a layering material (26) for the resin covering layer is then coated onto the resin covering layer (B) to restore the thickness (T1) of the resin covering layer (B), which has been reduced by grinding, to substantially an original thickness (T0).

Abstract: A method for feeding a solid-liquid mixture comprised of a liquid and a solid having a specific gravity greater than that of the liquid comprising depositing the solid component around a feed opening disposed at the bottom of a mixing container and feeding the solid-liquid mixture to a container for packing the same through the opening is provided and the method can effectively be carried out utilizing an apparatus comprising a mixing container, a feed opening disposed at the bottom of the mixing container, a feed controlling device disposed below or within the feed opening and characterized in that it comprises a collecting device for depositing the solid component of the mixture around the feed opening.