Principle
As a device that removes diverse organic gases and odor by absorption due to chemical combination of gas and free combination of atoms in the solid surface formed by molecular layer, it is equipment with strong absorption ability. It uses the principle of gas particulate material, contacting and being attached to the solid surface and if such absorption phenomenon is used, even when gas, liquid or sold concentration is very low, it is used widely as it can remove selectively when using a uniform absorbent.
Characteristics
- · The bigger the specific surface area and affinity, the bigger the effect of absorption becomes.
- · The absorbent (solid) is porous and the more capillary, the interface of solid needed for absorption increases.
- · It can repeat absorption regeneration and be continually used. (3-5 years life expectancy maintenance after self-production)
Type and Use of Absorbent
| Absorbent | Use |
|---|---|
| Activated carbon | Solvent recovering, odor removal, gas purification (most used) |
| Alumina | Drying of gas, air and liquid |
| Bauxite | Oil removal of petroleum, drying of gas and solution |
| Bone char | Bleaching of sugar |
| Decoloring carbon | Removal of oil, pigment, oil and wax, bleaching of drink |
| Fuller’s earth | Refinement of lubricant, fat, wax |
| Magnesia | Gasoline and solvent refining |
| Silica gel | Removal of impure parts from the caustic soda solution |
| Strontium sulfate | Drying and refinement of gas, removal of iron of caustic soda solution |
Although activated carbon only absorbs moisture if there is moisture in the mixed gas, if there is no gas, it absorbs organic and inorganic gas. Alumina and bauxite is used or bleaching (removal of moisture).
Maintenance
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- Dust Problem
- One must be careful to prevent inflow of dust that closes the absorbent surface during operation. As the absorbent surface area decreases and the small capillary within the absorbent is closed, absorbing efficiency is low. Therefore, the dust removal filter must be installed on the absorbed phase.
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- Corrosion
- During desorption stripping, the material becomes corrodes due to steam. If the steam temperature rises, the corrosion increases comparatively. Therefore, to prevent corrosion, the material must be stainless or the surface processing must be done separately.
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- Polar and Non-polar Compounds
- Although activated carbon can absorb all polar and non-polar compounds, to recover polar materials in the steam during stripping, additional types and separation methods are required.
VOC (Volatile Organic Compound) Removal Equipment
Air pollution occurs in hydrocarbon organic compound group such as partially oxidized organic acid, ketene and aldehyde as well as organic material that contains hydrocarbon, chlorine, nitrogen and sulfur.
Applied Area
- Fodder factory / painting booth / VOCs business such as organic solvent / terminal disposal plant of sewage at petro chemistry factory