Abstract: Process wherein a low CO2 content process gas generated by an ammonia-soda process unit or a refined sodium bicarbonate unit is enriched by using a Temperature Swing Adsorption CO2 concentration module into a CO2 enriched gas whose CO2 content is increased by at least +10% by volume on dry gas basis relative to the process gas, and which is subsequently recycled to the ammonia-soda process unit or optionally to the refined sodium bicarbonate unit, in order: to produce sodium carbonate, or sodium bicarbonate, or to carbonate at least part of effluent from the unit for producing sodium carbonate or bicarbonate.

Abstract: Process for producing sodium carbonate with ammonia and/or for producing refined sodium bicarbonate, wherein: a low CO2 content gas generated by a unit for producing sodium carbonate with ammonia and/or generated by a unit for producing refined sodium bicarbonate is enriched into a CO2-enriched gas by using a CO2 concentration module, such as an amine-type or ammonia or PSA or TSA or cryogenic distillation or membrane-type CO2 concentration module, and said CO2-enriched gas has an increased CO2 content of: +10% (at least) to +90% (at most), by volume on a dry gas basis relative to the CO2 concentration of the low content gas, and the CO2-enriched gas is subsequently recycled to the unit for producing sodium carbonate with ammonia and/or to the unit for producing refined sodium bicarbonate, to produce sodium carbonate, or sodium bicarbonate, or to carbonate at least one part of effluent from the unit for producing sodium carbonate and/or from the unit for producing sodium bicarbonate.