Reverse-jet scrubber apparatus and method

An improved reverse-jet scrubber apparatus for scrubbing particulate matter and gaseous contaminants from a gas stream, which apparatus comprises in combination:

• (a) an elongated conduit having an inlet at the one end for the introduction of the gas stream to be scrubbed and an outlet at the other end for the discharge of a scrubbed gas stream, the conduit having an interior wall surface and a defined diameter;
• (b) jet-spray means within the conduit comprising at least two jet-spray nozzles in series and spaced apart from each other within the conduit at not greater than about four times the hydraulic diameter of the conduit;
• (c) means to introduce a scrubbing liquid into the jet-spray nozzles and to spray the scrubbing liquid countercurrent to the passage of the gas stream from the inlet to the outlet, the scrubbing liquid sprayed under sufficient force and pressure to overcome initially the force of the gas stream to form scrubbing zones, each scrubbing zone covering substantially the cross-sectional area of the interior of the conduit, and each scrubbing zone not overlapping substantially with any other scrubbing zone, whereby the gas stream to be scrubbed, having a gas-flow parameter of 4.0 or greater, passes through the scrubbing zones at a high velocity, to provide a scrubbed gas stream containing entrained liquid material;
• (d) a wetting means comprising a hollow, truncated, conical collar element disposed and axially aligned generally with the smaller diameter end facing and upstream of the jet-spray means and spaced apart from said conduit by a small, annular gap, which gap provides fluid communication between the interior of the collar element and the interior of the conduit;
• (e) tangential, jet-spray nozzles at the base of the collar element, to provide a swirling liquid spray of the scrubbing liquid solution, whereby the swirling liquid spray passes through the gap and into the interior of the conduit and forms a thin liquid film on the interior peripheral wall of the conduit;
• (f) gas-liquid separator means downstream of the jet-spray means to separate the entrained liquid material from the scrubbed gas stream;
• and
• (g) means to withdraw the separated, entrained liquid material for disposal or reuse in the jet-spray means,
• whereby a gas stream to be scrubbed is introduced into the inlet of the conduit, and having a gas-flow parameter of 4.0 or greater, and is scrubbed with scrubbing liquid in the scrubbing zone, and a scrubbed gas stream with reduced particulate matter and gaseous contaminants is discharged from the outlet of the conduit.