Abstract: In a valve on a processing plant in the chemical apparatus field, which has a valve housing, a feed flange and a discharge shaft, together with a valve seat arranged in the vicinity of the feed flange and an associated valve cone, at least the contacting parts of the valve seat and valve cone are made from metal. The inner wall of the valve seat formed as a surface of revolution is provided in the flow direction with two adjacent areas having different diameters and which are separated from one another by an edge. When the valve is closed, only the valve seat edge engages on the circumferential surface of the valve cone. In the first area facing the feed flange, the valve seat wall preferably has a substantially constant radius which continuously increases in the flow direction in the following second area, resulting in particularly reliable closing behavior. This can be further aided by an axially acting spring element.

Abstract: There is disclosed a nutsch filter having blades fitted to a central, vertically positioned hollow shaft by a hollow arm, the blades having a plough-like cutting edge and a spatula-like bottom surface acting in the opposite movement direction. A discharge pipe, arranged concentrically to the hollow shaft, is axially displaceable. The discharge pipe is moved upwards against a cover for sealing the filter casing. The filtration or resuspension or drying of the filter cake takes place in this position. In order to discharge the compressed filter cake, the upper edge of the discharge pipe is set by the blades to the level of the paring or skimming process. Paring of the filter cake and conveying of the pared mass into the central discharge pipe opening takes place in a single operation by means of the blades. On drying, hot air or a hot fluid is passed through the cavities of the arm as well as the parts connected thereto.