Mesh Type Coalescing Devices, like mesh pads utilised for demisting applications, typically comprise a pad of knitted wire (the “mesh”) supported by a framework (weld mesh or grid). They are utilised when either a high separation efficiency and/or a high turndown ratio is required. As coalescing devices, they are positioned upstream of the demisting device and can be utilised in any configuration in horizontal and vertical separators.

The difference between the Mesh Type Coalescing Device and a Mesh Type Demisting Device is that the coalescing device is designed to operate at about three times the gas velocity used for a Mesh Type Demisting Device. This means that it operates in a flooded condition, which has the effect of enlarging the sizes of the droplets, thereby increasing the amount of liquid removal within the downstream demisting device and improving the efficiency of the gas/liquid separation process.

At low flows, the Mesh Type Coalescing Devices takes over from the downstream demisting device and itself acts as the demisting device. In this situation, it no longer operates in the flooded condition but reverts back to its role as a Mesh Type Demisting Device.

Further, since it provides a pressure drop prior to the demisting device, any flow mal-distribution at the face of the Mesh Type Coalescing Device will be significantly reduced before it reaches the demisting device, again offering benefits to the gas / liquid separation process.

Please note that we do not recommend the installation of Mesh Type Coalescing Devices where fouling or blockage is possible. Instead, for fouling or dirty duties, we recommend the use of our proprietary Vane Type Coalescing Device.

Advantages  
·Increases the gas / liquid separation efficiency 
·Improves the flow distribution on the face of the downstream demisting device 
·Provides a wide operational range with a high turndown ration ≥ 10:1 
·Available in various shapes and orientations 
·Can be supplied in various materials 
·Has relatively low installed cost 
·Easy to install in both new and existing separators 
·No moving parts, so no maintenance (for clean duties). 

Application  
·Production Separators 
·Test Separators 
·Gas Scrubbers 
·Gas Knock-out Drums 
·Slug Catchers 
·Flash Drums 
·Process Vessels and Columns 
·Floating Production Units (FPUs).