Gas purification techniques

Dry Lime absorption
Lime absorption is a technique where acid components in smoke - and degasses such as HCl, HF and especially SO₂ is removed with chemical absorptions. At dry industrial gas clean-up lime or limestone in dry land is converted into fine mist in the smoke gases. The response between dry lime or limestone and the acid components in the industrial gas takes place in an engine and partial in the in series substance dissidence, after the pollution to the lime has been absorbed by chemical absorptions. The reactor is necessary to guarantee a sufficiently long response time, of some seconds, between in the industrial gas flow the chemicals and pollution.
The injection of lime is sometimes carried out in the engine. However it is also possible inject lime for the reactor in the industrial gasses. At the developing of the reactor and also at the provision of the necessary excess to chemicals the choice of the technique emission control for disposal of the substance is very important therefore. The response takes place after absorption of the gaseous pollution to lime. Because of the small contact suggesting area the necessary excess to chemicals much is larger than at semi-dry cleaning method. At the same time with the dissidence of dry the response products and the excess to chemicals also dust shape pollution can be broken away from. Used chemicals and the separated pollution becomes partial recycled. Still the chemical usage and the quantity of the captive substance are at dry cleansing is considerably higher than at semi-dry cleaning. There are 2 types alternatives on Holland: Cascade - or packing absorption: The absorbent are not injected in the gas flow, but the gas flow are conducted though fixed adsorption beds. The response between the sorption medium, generally calcium carbonate, and the industrial gas pollution happen in a space in which the sorbens fall under the influence of the gravitation and where the industrial gases flow in counter-current or in cross are conducted through it. The adsorbent are used under form of granulates which must satisfy to certain specifications concerning size, composition and porosity to obtain purification output maximal. Sorbalite: At this technique a mixture of lime and active carbons is injected. This technique offers the advantage that the acid components are not only removed, but to be the active carbon looks also that PCDF's and PCDD's for large absorbed. This technology results however in large quantities of heavily polluted rest substance The advantages at this purification are: Small extra investment costs when dust removal preïnstallation are present Can be obtained there high output at a good engine concept No effluent The disadvantages are: Require large excess to sorbens Click here for overview over scrubber technology For more books and reading information see our website: Air treatment books overview

Gas purification techniques

Dry Lime absorption