Venturi Scrubber can have a rectangular or circular cross-sectional flow channel. This is installed to remove fine particles from volatile and hazardous or corrosive gas streams, or gas streams containing solid materials that are difficult to handle. In the throat, a bank of nozzles on either side of the throat injects water into the venturi throat. The water forms a curtain that is perpendicular to the airflow direction. The high velocity gas atomizes the liquid injected into the gas stream. It is normally assumed that the fine particles enter into the venturi throat with a velocity equal to that of the gas stream. The area ratio between the inlet and the throat across sections is typically 4:1. This is used to increase liquid atomization and to accelerate the liquid droplets. These have low performance efficiency due to their use of high pressure-fans. They collect coarse or fine particulate, including particulate less than 1 micron and particulate that is sticky or high in moisture. They are used for applications with high dust loadings. They are continuously wetted and therefore not vulnerable to clogging, plugging and scaling. These are used in pharmaceutical manufacturing or laboratory gas scrubbing.