Products
Absorption scrubber
PlasmaAir AG plans, designs and builds absorption scrubbers to reliably remove gaseous pollutants such as ammonia, hydrogen sulphide, hydrogen chloride, sulphur dioxide and amines from industrial exhaust air streams.
Counter-current absorption scrubbers provide favourable design conditions for physical and chemical absorption, achieving high pollutant removal rates in compact systems.
PlasmaAir AG builds absorption scrubbers for exhaust air volume flows of 200 to 120,000 standard m³/h. Each scrubber is specially designed for the respective application in terms of process engineering.
The procedure
The exhaust air is cleaned of pollutants based on their solubility in the scrubbing liquid.
Physical absorption – The pollutant dissolves in the scrubbing liquid. The separation efficiency is determined by the solubility equilibrium; once this is reached, the process comes to a standstill.
Chemical absorption – The dissolved pollutant reacts chemically in the scrubbing liquid. This process is not limited by solubility. For fast reactions, the size of the interface between the gas and liquid determines the absorption capacity.
The scrubbing liquid is tailored to the pollutant to be removed in order to achieve optimum efficiency.
Construction method
PlasmaAir offers vertical packed-bed scrubbers as standard. The columns are usually made of plastic (PP or PE), as the pollutants in the water are predominantly acidic or alkaline. This results in a maximum operating temperature of 60 °C; for higher exhaust-air temperatures, a cooler or quench is installed upstream.
The packing consists of either a random bed of high-performance packing elements or structured packing. At the top of the column, the gas then passes through a droplet separator.
For design purposes, the pressure drop is determined mainly by the diameter and irrigation density, while the separation efficiency depends on the height of the packed bed. The diameter is calculated from the air volume flow rate, whereas the bed height is recalculated for each application.
Benefits
Separation efficiencies of up to 99.9%
Large, continuously renewed gas–liquid interfaces
Low pressure drop across the equipment thanks to specially selected high-performance packing
Corrosion-resistant materials for the equipment and internals – plastics, stainless steels and ceramics
Compliance with limit values according to substance class
Separable pollutants
Absorption scrubbers are used to reduce gaseous pollutants, predominantly inorganic compounds:
Ammonia (NH₃)
Hydrogen sulphide (H₂S)
Hydrogen chloride (HCl)
Sulphur dioxide (SO₂)
Amines