Gas scrubbing

The spraying of reagents into a gas to remove contaminants, or to change the makeup of the gas, is common in many chemical processes.

Modern emissions legislation in many countries means there are strict controls on the levels of pollutant gases that can be emitted from industrial, chemical, or power plants.  SNP offers a variety of nozzles that operate in these often very harsh conditions. However, not all scrubbing applications are led by environmental issues.  Scrubbing and cooling gases are commonly performed to remove heat or contaminants to extend the life of linings and equipment further downstream in the process.

Engineering considerations for gas scrubber nozzles

Different designs of scrubber will require different types of nozzles and spray properties to operate effectively. The key engineering considerations to be made when selecting nozzles for gas scrubbing applications are listed in the blue menu on the right-hand side of this page.  Below this, through the grey menu, details on the different designs of suitable gas scrubbing nozzles are accessible.

The information contained in both the engineering considerations pages and the nozzle designs pages is summarised in the "Gas scrubbing nozzle cheat sheet" which is accessed by the orange button also to the right-hand side of this page.

More video content

For our series of Gas Scrubbing explainer videos and articles looking at key questions when selecting spray nozzle systems for different gas scrubber types, please follow the links below:

1. A Quick Guide to Gas Scrubber Types
See the here or, to read the guide in article form, click Gas Scrubber Types Explained
2. Spray Nozzle Selection for Gas Scrubbers
See the video here or, to read the guide in article form, click  Nozzle selection for gas scrubbers.
3. The Importance of Droplet Size in Gas Scrubber Systems
See the video here or, to read the guide in article form, click The importance of droplet size in gas scrubbing designs.
4. Using Computational Fluid Dynamics (CFD) for Gas Scrubber Design
See the video here or, to read the guide in article form, click CFD for Gas Scrubber Design.
5. Spray Nozzle Positioning in Gas Scrubbing Systems
See the video here or, to read the guide in article form, click here.
6. Testing and Documentation Requirements when Selecting Spray Nozzles for Gas Scrubbing Systems
See the video here or, to read the guide in article form, click here.

Nozzle Selection

A variety of nozzles are suitable for gas scrubbing applications. For packed bed scrubbers TF spiral nozzles can give very wide distribution patterns with up to 170 degree spray angles. TF nozzles are also useful in absorber spray scrubbers as they produce sprays with good levels of atomisation. 

If fast moving gas flows need to be overcome then large droplets may be desirable so SC or MP nozzles might be suitable as these produce large droplets with high momentum sprays

For very small gas flows that require quick scrubbing low flow, very fine scrubber sprays will be suitable so P, PJ or L series misting nozzle might be a good choice.