GB738854A - Improvements in dust disposal apparatus - Google Patents

Abstract

738,854. Centrifugal separators. BABCOCK & WILCOX, Ltd. Feb. 11, 1954 [Feb. 13, 1953], No. 4161/53. Class 23. [Also in Groups XXVIII and XXIX] In a dust-separating apparatus comprising a cyclone 9, a chamber 16 below the cyclone, and a bunker 1 below the chamber, valves 73, 113 are respectively provided to seal the lower outlets from the cyclone and chamber, a valve 98 is provided for equalizing the pressure in the bunker and the pressure in the chamber when the valves 73, 113 are closed, and a valve 92 is provided for substantially equalizing the pressure in the cyclone and the pressure in the chamber when the valves 73, 113 are closed. During most of the separation the valve 73 is open and the valves 113, 92, 98 are closed so that dust collects in the chamber, the dustladen air being supplied by a outlet 8 and clean air being withdrawn by an outlet 10 fitted with an ejector (see Group XXVIII) so that the cyclone operates at sub-atmospheric pressure. After a predetermined period of separation the valves are automatically operated by a system (Fig. 8, not shown) comprising a timer, an electric motor driving a cam-shaft, electric switches operated by the cams, and electromagnetic units connected to the switches and controlling supply of fluid to the hydraulic cylinders actuating the valves. After the valve 73 is closed the valve 98 is opened so that air from the bunker flows through pipes 99, 90, 100, 101, 102, 103 to the chamber to equalize the pressures. The valve 113 is then opened and closed after the dust collected in the chamber is discharged to the bunker. After closure of the valve 113 the valves 98, 92 are respectively closed and opened so that air from the chamber passes through a pipe 93 to the inlet 8 to substantially equalize the pressures in the chamber and the cyclone. The valve 72 is then closed and the valve 73 opened, all the valves remaining in their positions for a fixed period after which the valve operating cycle is repeated. A bag filter is fitted at the top of the bunker to permit air to enter the bunker when dust is withdrawn therefrom. Dust from the bunker passes to a mixer and after damping to a suitable degree is discharged to a vehicle for removal. The chamber 16 is provided with a dust level indicator 81. In a modification the lead indicator is incorporated in the valve control system, so that valve operating cycle commences when the dust in the chamber reaches a predetermined level. In a further modification, in which the dust is supplied to the cyclone under pressure, the pipe 93 is connected to the air outlet 10 and the pipes 100. . . 103 are dispensed with. The invention may be applied to a series of units, comprising a cyclone and a chamber, mounted on a common bunker.