Hamworthy Combustion Venturi Scrubbers are expressly designed for ensuring cutting edge collection efficiency on dust and aerosols generated by modern Thermal Oxidizers where very fine dusts are usually generated and variable gas flow rates are customary due to the fluctuations on the amount and composition of the incinerated wastes. Dust laden gases enter the Venturi from the top and are accelerated in the throat section. Liquids are fed to the plug-bob through a central nozzle and to the converging walls through tangential inlets that create a uniform liquid film spinning down to the throat section. Gases impact the liquid curtain in the throat section and atomize it, thus generating a mixed phase characterized by a huge amount of very fine liquid droplets dispersed in the gas stream. As gas pass through the energy recovery section of the Venturi Scrubber, dust particles contact the liquid droplets both via Direct Impingement and via Brownian Diffusion and are scrubbed away. The highly turbulent mixing between the gas phase and the atomized liquid droplets offers also a huge contact surface for heat and mass transfer. The gas stream and the washing liquids leave the Venturi Scrubber through a flooded elbow where a layer of liquid resting on the bottom prevents mechanical shocks and abrasive wear.
Up to 98% collection efficiency on 1.0 µm equivalent diameter dust particles can be achieved. High-Energy Venturi Scrubbers with pressure drop up to 250 mbar for high efficiency on sub-micron particles can be supplied. Gas flow rates up to 170,000 m3/h (100,000 acfm) can be processed in a single unit. Open-pipe liquid feeding for low feeding pressure and optimized L/G ratios for low pumparound ensure minimum pump requirements. Recycle tank can be integrated in the downstream wet scrubbing system or dedicated to the Venturi stage. Scrubbing liquids can be recycled slurry with suspended solids and dissolved salts. Manual Throat Adjustment or Automatic Throat Adjustment can be supplied. Single Venturi units as well as complete packages including scrubber, piping, ductworks, rotating equipment etc. can be supplied. ASME Code or any other international pressure vessel design code can be applied.