In order to ensure that there are no solids in the amine system, Axens recommends an amine filtration package which filters a slipstream of the lean amine to remove solid particles. The amine filtration package also includes an activated carbon filter for hydrocarbon elimination and a polishing filter to remove any charcoal fines.

Axens also recommends an amine filtration sequence for early and first start-up of the acid gas removal unit (AGRU) according to the actual level of solids: first use temporary cartridges with 100 microns absolute filtration rate, then 40-50 microns absolute filtration rate, then final grade. In order to minimise the foaming tendency of the amine solvent, solids content has to be minimised. If the source of the solids is from the feed gas where they could also cause foaming in the absorber, Axens requires installation of a feed gas coalescer upstream of the amine contactor to protect the amine contactor from foaming upsets that can reduce the capacity of the whole process chain.

As the coalescing elements may plug if solids are present in the feed gas, it is advised to install solids filtration upstream of the coalescer. This solids filter protects coalescing cartridges and increases their lifetime, reducing opex and associated maintenance costs.