The correct scrubbing chemical is selected according to the pollutants present in the contaminated air and the chemical reactions required to remove them effectively. Different gases behave differently when they come into contact with a liquid, so the scrubbing solution needs to be matched to the contaminant rather than using the same chemical treatment for every application.
Factors such as pollutant concentration, airflow, temperature, moisture levels and required removal efficiency also influence the selection.
Exeon’s scrubX™ wet scrubber system uses automated chemical dosing and process controls to help maintain the conditions needed for effective treatment of gases including ammonia, hydrogen sulphide and acidic compounds.
Which Chemicals Are Used for Acidic Gases?
Acidic gases are generally treated using an alkaline scrubbing solution capable of neutralising the pollutant as it transfers from the contaminated air into the liquid.
Examples of contaminants that may be treated in this way include hydrogen chloride, sulphur dioxide and other acidic industrial emissions.
The strength and composition of the solution will depend on the gas concentration and treatment requirements. Correct control of factors such as pH is important because the chemical conditions within the circulating liquid directly affect how efficiently pollutants are removed.
Wet scrubbing is therefore particularly useful for industrial processes generating soluble or chemically reactive gases that can be neutralised through controlled liquid treatment.
What About Hydrogen Sulphide?
Hydrogen sulphide can require different treatment chemistry depending on its concentration and the overall composition of the air stream.
In suitable applications, an oxidising or chemically reactive scrubbing solution can be used to convert or neutralise H₂S after it transfers into the liquid phase.
Where several pollutants are present, more than one treatment stage may be appropriate. Activated carbon or biological filtration can also be considered as part of a broader industrial odour and emission control system.
What Information Is Needed Before Selecting the Chemical?
Before the scrubbing chemistry is specified, the process air should be assessed for:
- Pollutant type and chemical composition
- Normal and peak concentrations
- Airflow rate
- Temperature
- Humidity and moisture content
- Required removal efficiency
- Variations in process conditions
- Compatibility with equipment and downstream treatment
- Requirements for handling the spent scrubbing liquid
This information helps determine not only which reagent is appropriate, but also the required dosing arrangement and operating conditions.
The scrubX™ system continuously circulates the treatment liquid and uses automated controls to adjust chemical dosing as required. Fresh make-up liquid can be introduced while spent solution is removed through the appropriate liquid-management process.
Exeon offers several industrial air filtration technologies, so wet scrubbing can also be compared with activated carbon adsorption or biological treatment where appropriate.
Correct chemical selection is fundamental to wet scrubber performance. By matching the scrubbing solution, dosing controls and system design to the actual emissions, scrubX™ can provide controlled and efficient treatment while avoiding unnecessary chemical use and maintaining consistent pollutant removal.
Contact Exeon today to arrange a site consultation or request a tailored proposal. Our technical team will assess your airflow volumes and contaminant profile to design a system that delivers consistent emission control.