Passive Gas Scrubbers
A passive gas scrubber is a compact and simple solution for limited or temporary vapor flows, such as during the venting of smaller storage tanks. The positive pressure in the tank forces the vapors through water or a suitable scrubbing fluid, which absorbs the contaminants. Since no pump or complex control system is required, the system requires only minimal maintenance.
The gas scrubber can be integrated with:
- the tank venting system
- a vapor return line
- the filling line or filling cabinet
- low- and high-pressure safety devices
- level measurement
- automatic supply of washing fluid
- a signal from the filling or unloading process
Insulation and tracing for passive scrubber
Passive scrubber with flow rate up to 30 m³/hour
A passive gas scrubber is a compact solution without a circulation pump or powered fan. The overpressure in, for example, a storage tank forces the vapors through the scrubbing liquid, where the contaminants are absorbed.
This type may be suitable for:
- venting smaller storage tanks;
- limited and temporary vapor flow rates;
- displacement air during filling;
- components that are highly soluble in water;
The passive gas scrubber consists of a small tank that is usually filled with water. The chemically laden vapor is passed through the water to be cleaned and then exits the scrubber through the vent in the roof.
A major advantage of a passive gas scrubber is its simplicity: the liquid simply needs to be replaced on a regular basis. Therefore, no pump or control system is required. The liquid can freeze, but this can easily be prevented by draining it in the winter, adding insulation and heat tracing, or adding glycol to the water.
The contaminated water must be treated by a wastewater treatment plant or can be used in a specific process. Water consumption depends primarily on the solubility of the medium to be washed, the odor threshold, and the flow rates to be processed.
