Steam injection assembly for disc filter

Claim 1

In a rotary disc vacuum filter for steam-assisted pressure differential filtration, the filter having a tank with upstanding sidewalls so as to contain slurry to be filtered; a disc filter element mounted in the tank for rotation about a horizontal trunnion so as to pass into and out of the slurry in the tank; and a hood mounted on the tank to define a chamber for a single disc filter element and through which the disc filter element rotatably moves, the hood having a pair of spaced-apart vertically-extending sidewalls to define a space through which sectors of the disc filter element sequentially pass, a spine wall which sealingly joins the pair of sidewalls, and a seal means mounted on the sidewalls of the hood to define a stream-retaining exit for the chamber, the seal means including two elongated flexible flaps which are mounted to opposite ones of the sidewalls so as to sealingly press against cakes of filter solids formed on the surface of the sectors of the disc filter element, an improved introduction assembly connected in flow communication to the hood for conveying steam into the chamber comprising first and second elongated tubular members each of which is connected to support one of the pair of sidewalls as an essential element of a tubular frame which is the sole support for the hood and each of which extends from the spine wall along the sidewall towards the seal means and comprising orifices formed through and spaced along each of said elongated tubular members between the spine wall and the seal means to provide flow communication between said elongated tubular members and the chamber.