Abstract: A water-excluding vent structure wherein water impinging upon an outer surface thereof is excluded while air is allowed to freely flow through the vent structure to an internal space. The circular or other appropriate shaped vent structure has a series of parallel louvers designed for orientation in a level, horizontal plane. A porous, polypropylene membrane is placed behind the louvers. A perimeter gasket is used to seal the vent structure to the object to be ventilated. A notch is formed in an inner edge of the perimeter gasket along a line which is a perpendicular bisector of the louvers. The space defined by the notch is communicative with a drain hole in the outer housing. When properly oriented with the notch in a lowermost position, any moisture passing through the porous membrane collects in the notch and flows through the drain hole.

Abstract: Disclosed is a separator for separating a meltable solid from a mixture with other solids. The separator has a tank for holding a fluid; a container at least partially inside the tank, made at least in part of a screen through which the fluid can pass and melted solids can flow, but through which the unmelted solid material will not flow; and a heater for heating the fluid above the melting point of the meltable solids. Also disclosed is a method of separating a meltable solid from a mixture with other solids. The mixture of solids is placed in the container of the separator and the fluid is heated to a temperature above the melting point of the meltable solid, whereby the meltable solid flows through the screen out of the container, while the other solids remain within the container.

Abstract: The invention comprises a screening device for separating fine particles from a stream of air and a particulate mixture containing coarse and fines which includes a box-like hollow housing tilted downwardly at an acute angle. The housing contains a plurality of elongated screening elements and an air cleaning device consisting of a blowpipe and a series of nozzles directed at the screening elements through Venturi tubes. At periodic intervals a jet or pulse of air is injected into the Venturi tubes to reverse air flow and rid the screen elements of adhered coarse particles. Substantially complete fines removal can be achieved by employing a recycling loop between the coarse particle outlet and inlet of the housing.

Abstract: A method and apparatus for removing stringy contaminants from a pulp in a wastepaper recovery system having a pulping vat with an elongate helically shaped rod in the vat with means for causing a relative rotation between the stock and the helical rod so that long slender contaminants will be captured and climb the rod. In one form, multiple helices are employed and the rods may be driven in rotation, or the stock caused to rotate about the helix by other means.

Abstract: A rotary pulp screening device of the horizontal type is disclosed having a high screening efficiency and high capacity. The screening device provides a streamline flow of pulp and one of its aims is to supply a fairly constant velocity of pulp along the length of the screen thus utilizing its full length.