Water Scrubbing

Water scrubbing of soluble VOCs

In selected cases, soluble volatile organic compounds (VOCs) such as ethanol and acetone can be removed from vent gases using water scrubbing in a packed tower, rather than thermal oxidation or carbon adsorption. ERG has successfully designed and installed water‑only VOC scrubbers where the scrubbing liquor can be reused or treated effectively on site.

Operating principle and when water scrubbing works

In a water scrubbing system, VOC‑laden gas is contacted with process water in a packed tower, typically in counter‑current flow. The water absorbs soluble VOCs such as ethanol and acetone, and the resulting blowdown stream is managed via reuse, treatment or discharge.

This approach is particularly attractive when:

The scrubber blowdown can be returned to the process, allowing the fume abatement package to recycle feedstock that would otherwise be lost.
There is a site effluent treatment plant (ETP) designed to biologically digest the captured VOCs.
In some cases (though not usually preferred or permitted), the site effluent discharge consent can accommodate the scrubber blowdown directly.

Water scrubbing is not suitable for many VOC duties, but for specific applications it is considered BAT (Best Available Technique), with the advantages of relatively low capital cost, low running costs and low energy demand.

ERG’s process designs ensure that VOC emissions meet the agreed guarantee, and that biocide dosing is included where necessary to eliminate the risk of legionella in recirculating systems.

Contact our sales team for more information about how ERG can assist with your VOC abatement.