Abstract: An environmentally-friendly exhaust device comprises an outer tank. An inner pipe is disposed inside the outer tank. An air propeller is disposed below the inner pipe inside the outer tank. An upper guiding plate and a lower guiding plate are disposed on a surface of the inner pipe for connecting with the outer tank. Thereby, air, oil mist and water are entered between the outer tank and the inner pipe; and are guided to the air propeller below through the upper and the lower guiding plates; and then are exhausted through the inner pipe upwardly. The purification of oil mist is processed integrally for enhancing the efficiency of exhaust and achieving the environmentally-friendly effects. Multiple layers of filter screens provided for carrying out multiple filtering are economically effective and can further enhance the environmentally-friendly effects.

Abstract: A method of removing liquid contaminant droplets from a gas stream, comprising providing a wash tray in a vessel with at least one swirl tube device; admitting the gas stream including liquid contaminant droplets into the at least one swirl tube; admitting wash liquid into the gas stream in the at least one swirl tube, to form a gas/liquid mixture with wash liquid droplets dispersed in the gas stream; allowing the wash liquid droplets and liquid contaminant droplets to interact in a scrubbing section; passing the gas/liquid mixture along a swirl imparting means so as to perform centrifugal separation into washed gas and liquid, and removing washed gas and liquid. Moreover a swirl tube wash tray for use in a vessel for removing liquid contaminant droplets from a gas stream by means of a wash liquid, which wash tray comprises having a wash liquid supply means with an outlet opening some distance above a liquid supply space.