PSA process, short for Pressure Swing Adsorption, consists of 2 beds (or towers) filled with Carbon Molecular Sieves (CMS). Compressed air, from which Nitrogen is to be extracted, is first filtered through a series of pre-filters. MVS utilises multi-stage filtration, including activated carbon filters, to ensure that no dust or oil carries over.
Pre-filtered compressed air is passed through one CMS bed and Nitrogen comes out as the product gas. After some time, the CMS bed is saturated with waste gases. Upon saturation of the CMS bed, the process switches nitrogen generation to the other bed, while allowing the saturated bed to undergo regeneration by depressurization to atmospheric pressure. This ensures continuous supply of Nitrogen to your process. The waste gases (oxygen, carbon dioxide, etc.) are discharged back into atmosphere through a vent port.
There are 2 basic schemes that MVS offers to it’s customers. The first is a simple PSA wherein the Nitrogen plant only consists of one stage of PSA. The second scheme is used for higher purity needs and a de-oxo chamber is added for further removal of oxygen in ppm levels. We present the two schemes visually below.
Standard PSA models consist primarily of three distinct assemblies –
Feed air package can be supplied by MVS or the customer. The PSA assembly is supplied by MVS, consisting of highest quality air filtration from European filters and CMS from CarboTech (Germany). Product Nitrogen gas is pure and dry when it comes out of the CMS columns.
For customers requiring ultra-high purity (typically in ppm oxygen level), in addition to the assemblies of the standard PSA model, we add another two assemblies –
Nitrogen coming as the product from the PSA is taken to a de-oxo reactor where in presence of a catalyst, trace amounts of Oxygen react with Hydrogen and convert to water vapour (moisture). Nitrogen becomes pure, but now also has moisture content. In order to remove the moisture, pure Nitrogen is taken to a dryer where the gas becomes dry.