Emission Control
Vapour Recovery Systems — Comparison
2004·3 min
A side-by-side comparison of refrigeration, absorption and adsorption VOC recovery technologies — covering application range, safety, maintenance, cost and operational characteristics.
Dr. D.M. Mohunta, Commercial, Chemical and Development Company
A quick glance at the various differences between Refrigeration, Absorption and Adsorption methods of recovery systems from volatile organic compound (VOC) streams.
| Parameter | Refrigeration | Absorption | Adsorption |
|---|---|---|---|
| Application | Higher concentration | For low concentration — 0.5% | For low concentration — 0.5% |
| Process | Condensation | Separation and condensation | Separation and condensation |
| Operational Temp. | Very low temp. | Room and above | Room and above |
| Pressure Drop | Very low | Low | High |
| Vacuum | Not required | Required | Required |
| Operations | Fully automatic / continuous | Fully automatic / continuous | Automatic batch process |
| Maintenance | Low maintenance | Low maintenance | High maintenance |
| Power Cost | Power used when required | Continuous power even at no load | Continuous power even at no load |
| Installation Cost | Very low | Low | Large |
| Concentration Measurement | Not required | Required for outlet gas | Required for outlet gas |
| Space Required | Smallest | Small | Large |
| Steam | Not required | Required | Required |
| Inert Gas | Not required | Special circumstances | Required for safe operations |
| Carbon Replacement | Not required | Not required | Required — periodic replacement |
| Solvent Replacement | Not required | Required | Not required |
| Safety | Intrinsically safe | Safe | Precautions required |