أجهزة تنقية الغاز الفنتوري

Large Scale Venturi Scrubbers

The large scale Venturi Scrubbers are the best option when high separation capacities of large flow rates of dust laden gases are needed.

The scrubbing liquid is injected through several nozzles in the inlet cone preceding the venturi throat. The scrubber may be mounted vertically, inclined or horizontally. 

For cooling, gas conditioning and pre-dedusting, the scrubber is operated with a pressure drop of only a few mbar. The small pressure drop is obtained by approximately matching the velocity of the injected scrubbing liquid to that of the gas in the venturi throat. During deceleration in the diffusor, the relatively higher mass of the scrubbing liquid causes a further increase in the gas pressure. 

Depending on the volume of liquid injected, much energy may be transferred to the gas; this not only avoids a pressure drop in the scrubber but generates an increase in the gas pressure. In contrast, when operating this type of scrubber with a large pressure drop, the gas/dust mixture enters the scrubbing zone at a higher velocity that the scrubbing liquid. Hence, the liquid droplets are accelerated by the gas stream causing a pressure drop. As speed rises, increasing turbulence is simultaneously induced in the scrubber, bringing intensive mixing of the scrubbing liquid droplets and the raw gas, this being a prerequisite for high collection efficiencies. Therefore, the higher the gas velocity in the venturi throat, the larger the pressure drop.

The gas/droplet mixture is divided in a centrifugal separator which is arranged downstream.