ES306372A2 - Improvements in the manufacture of ceramic products - Google Patents

Abstract

In a tunnel drier for wet moulded ceramic articles, the articles are loaded on frame supports and pass through upper and lower drying tunnels 21, 41 and a gallery 61 in a trench by means of hoisting and lowering lifts 11. 31 and 51, respectively, the tunnels having individual air supply, control and recycling means such that the drying and recycled air is introduced into the tunnels in countercurrent to the articles and also flows in a helical path in the upper tunnel 21. The dry gas flows from a fan 71 through the tunnel 41 and passes through a second fan 91 into the upper tunnel in countercurrent to the articles for extraction through a chimney 1 A portion of air from the fan 71 also passes through a duct 181 beneath the upper tunnel and through valved openings 191 (Fig. 7) into spaced, vertical ducts 201 along the outer walls of the tunnel. The air is introduced via fans 241 into the upper tunnel with regulatable quantities of moist air from the chimney 111 which passes through ducts 251 communicating via valves with the ducts 201 to flow both in countercurrent and substantially in helical flow in the upper tunnel as a result of the transverse circulation and longitudinal movement towards the extraction chimney. In a modification the tunnel may be divided by transverse partitions (Fig. 2), or extend along a single floor overlying a single cooling tunnel (Fig. 9).