Moisture, Carbon dioxide, and hydrogen sulphide removal from natural gas are crucial to achieving perfect purification. These contaminants can affect the functionality of natural gases. Gases like CO2 and H2s are corrosive, flammable and toxic. In some of the industrial manufacturing processes, these contaminants can be generated as a by-product or by other means. Thus, removing them becomes crucial.

Molecular sieve for Biogas purification and bottling plant

A whole biogas plant consists of generation, purification and bottling units. The purification unit consists of a pressure swing adsorption unit that adsorbs gases selectively. The mesh-like networks of molecular sieves trap the gases into their cavities. Selective adsorption is achieved from the variation in the gas pressure. Molecular sieve for carbon dioxide removal hydrogen sulphide removal is one of the most used methods in the oil and gas, petrochemical and sugar industries.

Pressure swing adsorption

Biogas up-gradation plants use the technique called pressure swing adsorption or PSA that majorly comprises four vessels filled with molecular sieve pellets or beads. All four vessels alternate their operations. At a point, they can aid in the adsorption, regeneration, pressurization or depressurization process. These desiccants successfully adsorb the moisture, carbon dioxide, nitrogen and hydrogen sulphide from the natural gas stream. Upon adsorption of these gases, the methane or CH4 is then let outside the unit as the product.

In the pressurization phase, the pressure achieved by bringing the pressure to equilibrium and injecting raw biogas. The adsorption phase is all about the removal of CO2, H2S, N2 and moisture. Equalizing of the pressure of the adjacent vessel brings forth the depressurization phase. In the regeneration phase, by purging gases into the bed of desiccants, it is regenerated from the saturated phase.