Abstract: Washing tank for separating particles differing the specific gravity by means of a liquid separatory medium using the float-and-sink method. The washing tank is provided with at least one collecting tray for removing the settled particles, which collecting tray can be reciprocated along the bottom of the washing tank and in the first extreme position is about centrally on the bottom of the washing tank, where it can collect settling particles, and in the second extreme positions rests on the edge of the washing tank, so tilted that settled particles contained in it can slide into a discharge device positioned next to the washing tank. Preferably, the washing tank is provided with two alternating collecting trays hingingly attached to arms fixed on a horizontal shaft swinging to and fro between two extreme positions.

Abstract: The invention relates to a process for the manufacture of objects from water-hardened materials, reinforced with one or more reticulate webs, one over the other, which webs have been obtained by stretching, fibrillating and spreading of a film of organic polymeric material, by continuously supplying one or more reticulate webs, contacting them with a water-hardening material and water, thus forming a composite material, and shaping and hardening this material. This is obtained according the invention in that:a. one or more reticulate webs, one on top of the other, are continuously supplied and laid on a carrier;b. the reticulate webs are folded zig-zag on this carrier;c. the folded network is continuously transported in a direction virtually normal to the direction in which the reticulate webs are supplied;d. subsequently, the folded network is contacted, directly or indirectly, with a water-hardening material and water.

Abstract: The present invention relates to a continuous process for manufacturing articles comprised of fiber-reinforced hydraulically bound material. A layer of the fiber-reinforcing and hydraulically bindable materials are placed on a first endless carrier while a second similar layer is formed on a second endless carrier. The layer formed on the second carrier is deposited on the layer formed on the first carrier by reversing the second carrier and the composite layer formed as a result is thereafter given the desired shape and is hardened.A number of fibrous network structures are used with the hydraulically bindable material and the two are formed into a layer with the networks distributed in it. Water is removed from that layer by suction, while on the second carrier a number of fibrous networks are likewise supplied to be formed into a layer comprised of the hydraulically bindable material with the networks distributed in it and water is also removed by suction from this layer.