Abstract: A process gas is introduced into a treatment chamber (40) through a horizontal spiral gas supply duct (30) having a tangential inlet (31) and opening to a pair of concentric, inner and outer annular gas inlet ducts (12,22) surrounding a liquid spray apparatus (2). Partition means (32) divide the spiral supply duct (30) into independent inner and outer sub-ducts (34,36) which define separate inner and outer flow passages (44,46) connected respectively to the inner and outer annular gas inlet ducts (12,22). Damper means (70) is provided in the inlet to the outer sub-duct (36) to selectively control the flow of process gas (7) therethrough as a means of maintaining the velocity of the flow of process gas (5) through the inner flow passage (44) above a minimum acceptable velocity.

Abstract: An apparatus (40) for installing a coil spring (30) under tension between the discharge electrode wires (20) of a rigid-frame type electrostatic precipitator (10). The installation apparatus (40) comprises a longitudinally elongated support rod (42), first spring engagement pin (54) mounted stationarily to the outboard end (44) of the support rod, second spring engagement pin (64) supported from and translatably movable along the support rod, and spring tensioning device (70) for selectively positioning the second spring engagement pin (64) at the proper position along the support rod (42) so as to elongate the spring to the proper length necessary to slip the ends (34) of the spring about and between the discharge electrode wires (20).

Abstract: A bag filter housing (10) having filter bag tensioning means for providing a predetermined tension on each filter bag (28). The tension may be quickly released by means of a lever (40) incorporated into the bag tensioning means thereby allowing the filter bags to be quickly removed and replaced as necessary to maintain optimum dust collection performance.