Assembly for reducing co2 emission in plants for clinker production

A clinker production process configured to be conducted in a plant for the production of clinkers, the method comprising the following procedures:

• a) a first calcination reaction carried out in a primary calciner on a preheated raw material stream to give a first stream of CO2-enriched gas, which is removed and a first calcined material stream comprising CaO,
• wherein the primary calciner is a first of two calciners of the plant, the primary calciner preceding a carbonator of the plant, the carbonator arranged between the two calciners;
• wherein one of the two calciners is configured to continue to operate in a clinker production process even if a CO2 capture system of the plant that uses the carbonator and the other calciner of the two calciners is disconnected;
• wherein energy necessary to support the first calcination reaction is generated by an oxy-fuel combustion using as oxidizer a mixture formed by O2 and by a part of the CO2-enriched gas exiting from said primary calciner, in order to avoid dilution with nitrogen present in air;
• b) cooling the first calcined material to produce cooled CaO-enriched calcined material;
• c) a carbonation reaction performed with the cooled CaO-enriched calcined material to obtain calcium carbonate-enriched material;
• d) a second calcination reaction conducted in a secondary calciner of the two calciners with calcium carbonate-enriched material produced during the procedure c) to generate a second stream of CO2-enriched gas and a second stream of calcined material comprising CaO,
• wherein the secondary calciner is arranged downstream of the carbonator;
• wherein energy necessary to support the second calcination reaction is generated by an oxy-combustion using as oxidizer a mixture formed by O2 and by a part of the second stream of CO2-enriched gas exiting from the secondary calciner, in order to avoid dilution with nitrogen present in air;
• e) transforming the calcined material comprising CaO of the second stream into clinker in a rotary kiln with the use of heat provided by combustion of at least one fuel and air, and
• f) cooling a product produced by said transforming in a clinker cooler.