Search

EP-4741360-A1 - METHOD FOR THE MANUFACTURE OF LOW-CARBON-FOOTPRINT CEMENT

EP4741360A1EP 4741360 A1EP4741360 A1EP 4741360A1EP-4741360-A1

Abstract

The present invention relates to methods for integrating CO 2 -mediated mineral carbonation and/or activation in a cement production facility and methods for producing low-carbon-footprint cement, comprising withdrawing at least part of the exhaust gas generated cement production, conditioning it by modifying one or more of temperature, pressure, CO 2 concentration and humidity, subjecting an activatable solid feedstock to a size-reduction operation in a size-reduction apparatus distinct from the raw mill and cement mill, and producing low-carbon-footprint cement by mixing the CO 2 -activated material with the cement wherein mixing is performed feeding the CO 2 -activated material to the cement mill or a distinct mixing apparatus.

Inventors

  • SINHA, Apoorva

Assignees

  • Carbon Upcycling Technologies Inc.

Dates

Publication Date
20260513
Application Date
20241106

Claims (16)

  1. A method for the manufacture of low-carbon-footprint cement comprising the steps of: (i) subjecting a cement raw material to a size-reduction operation in a first size-reduction apparatus, thereby obtaining cement raw meal; (ii) subjecting the cement raw meal of step (i) to one or more pre-heating stages and to one or more calcining stages, thereby obtaining cement clinker and generating an exhaust gas comprising at least 0.5 vol% CO 2 ; (iii) subjecting the cement clinker to a size-reduction operation in a second size-reduction apparatus, thereby obtaining cement; (iv) withdrawing at least part of the exhaust gas generated in step (ii) and conditioning it by modifying one or more of temperature, pressure, CO 2 concentration and humidity, thereby obtaining a conditioned exhaust gas which has a temperature within the range of 30-300°C and comprises at least 0.5 vol% CO 2 ; (v) subjecting an activatable solid feedstock to a size-reduction operation in a third size-reduction apparatus in the presence of the conditioned exhaust gas, thereby obtaining a first CO 2 -activated material, and recovering the first CO 2 -activated material; (vi) optionally submitting the first CO 2 -activated material to one or more further treatments where it is contacted with a CO 2 -rich gas comprising at least 0.5 vol% CO 2 outside the third size-reduction apparatus, thereby obtaining a second CO 2 -activated material, and recovering the second CO 2 -activated material; and (vii) producing low-carbon-footprint cement by mixing the first and/or second CO 2 -activated material with the cement of step (iii), wherein mixing is performed (a) by feeding the first and/or second CO 2 -activated material to the second size-reduction apparatus of step (iii) while step (iii) is being performed; and/or (b) by mixing the first and/or second CO 2 -activated material with the cement obtained in step (iii) in a mixing apparatus different from the first, second and third size-reduction apparatus.
  2. The method of claim 1 wherein the conditioned exhaust gas used in step (v) has • a temperature within the range of 30-180°C, preferably within the range of 35-120 °C, most preferably within the range of 40-85 °C; • a relative humidity of at least 40%, preferably at least 60%, more preferably at least 70%; and/or • a CO 2 concentration within the range of 0.5-50 vol%, preferably 2-40 vol%, more preferably 5-35 vol%.
  3. The method of claim 1 or 2 wherein the D90 of the first and/or second CO 2 -activated material before the mixing of step (vii) is within the range of 0.5 to 120 µm, preferably within the range of 5 to 100 µm, more preferably within the range of 10-85 µm.
  4. The method of any one of the previous claims wherein step (iv) comprises withdrawing exhaust gas at one or more locations corresponding to a preheater stage, a calcining stage, or a flue gas stack.
  5. The method of any one of the previous claims wherein the exhaust gas withdrawn in step (iv) has a temperature of more than 200 °C, preferably more than 300 °C and wherein the conditioning of step (iv) comprises cooling the exhaust gas by at least 50 °C, preferably by at least 100 °C to provide the conditioned exhaust gas used in step (v).
  6. The method of any one of the previous claims, wherein step (vi) is performed and wherein the CO 2 -rich gas of step (vi) comprises at least part of the exhaust gas withdrawn in step (iv), wherein said exhaust gas may be used in step (vi) before or after said exhaust gas is used in step (v).
  7. The method of claim 6 wherein the exhaust gas is used in step (vi) before it is used in step (v) such that the conditioning of step (iv) comprises using at least part of the exhaust gas in step (vi), thereby effecting a change of temperature, pressure, CO 2 concentration and/or humidity of the exhaust gas.
  8. The method of any one of the previous claims wherein step (vi) is performed and wherein the moisture content of the first CO 2 -activated material is increased before and/or during step (vi), preferably by spraying an aqueous composition such as water on the solid material.
  9. The method of claim 8 further comprising a deagglomeration step which is applied during and/or after the moisture content of the first CO 2 -activated material is increased, the deagglomeration step being applied before and/or during step (vi).
  10. The method of any one of the previous claims, preferably of claim 8 or 9, wherein the conditioning of step (iv) comprises using at least part of the exhaust gas for drying the second CO 2 -activated material before the second CO 2 -activated material is mixed in step (vii).
  11. The method of any one of the previous claims wherein the conditioning of step (iv) comprises using at least part of the exhaust gas for drying the activatable solid feedstock before the activatable solid feedstock is size-reduced in step (v).
  12. The method of any one of the previous claims wherein step (vi) is performed and wherein recovering the second CO 2 -activated material comprises a deagglomeration step.
  13. The method of any one of claims 1-12 which comprises the steps of: (i) subjecting a cement raw material to a size-reduction operation in a first size-reduction apparatus, thereby obtaining cement raw meal; (ii) subjecting the cement raw meal of step (i) to one or more pre-heating stages and to one or more calcining stages, thereby obtaining cement clinker and generating an exhaust gas comprising at least 0.5 vol% CO 2 ; (iii) subjecting the cement clinker to a size-reduction operation in a second size-reduction apparatus, thereby obtaining cement; (iv) withdrawing at least part of the exhaust gas generated in step (ii) and conditioning it by modifying one or more of temperature, pressure, CO 2 concentration and humidity, thereby obtaining a conditioned exhaust gas which has a temperature within the range of 30-300°C and comprises at least 0.5 vol% CO 2 ; (v) (a) subjecting a first activatable solid feedstock to a size-reduction operation in a third size-reduction apparatus in the presence of the conditioned exhaust gas, thereby obtaining a first CO 2 -activated material, and recovering the first CO 2 -activated material; and (b) subjecting a second activatable solid feedstock to a size-reduction operation in a fourth size-reduction apparatus in the presence of the conditioned exhaust gas, thereby obtaining a third CO 2 -activated material, and recovering the third CO 2 -activated material; (vi) (a) optionally submitting the first CO 2 -activated material to one or more further treatments where it is contacted with a CO 2 -rich gas comprising at least 0.5 vol% CO 2 outside the third size-reduction apparatus, thereby obtaining a second CO 2 -activated material, and recovering the second CO 2 -activated material; and (b) optionally submitting the third CO 2 -activated material to one or more further treatments where it is contacted with a CO 2 -rich gas comprising at least 0.5 vol% CO 2 outside the third size-reduction apparatus, thereby obtaining a fourth CO 2 -activated material, and recovering the fourth CO 2 -activated material; and (vii) producing low-carbon-footprint cement by mixing • the first and/or second CO 2 -activated material; • the third and/or fourth CO 2 -activated material; and • the cement of step (iii); wherein mixing is performed (a) by feeding the CO 2 -activated materials to the second size-reduction apparatus of step (iii) while step (iii) is being performed; and/or (b) by mixing the CO 2 -activated materials with the cement obtained in step (iii) in a mixing apparatus different from the first, second, third and fourth size-reduction apparatus.
  14. The method of claim 13 which comprises the steps of: (i) subjecting a cement raw material to a size-reduction operation in a first size-reduction apparatus, thereby obtaining cement raw meal; (ii) subjecting the cement raw meal of step (i) to one or more pre-heating stages and to one or more calcining stages, thereby obtaining cement clinker and generating an exhaust gas comprising at least 0.5 vol% CO 2 ; (iii) subjecting the cement clinker to a size-reduction operation in a second size-reduction apparatus, thereby obtaining cement; (iv) (a) withdrawing at least part of the exhaust gas generated in step (ii) and conditioning it by modifying one or more of temperature, pressure, CO 2 concentration and humidity, thereby obtaining a first conditioned exhaust gas which has a temperature within the range of 30-300°C and comprises at least 0.5 vol% CO 2 ; and (b) withdrawing at least part of the exhaust gas generated in step (ii) and/or part of the first conditioned exhaust gas and conditioning it by modifying one or more of temperature, pressure, CO 2 concentration and humidity, thereby obtaining a second conditioned exhaust gas which has a temperature within the range of 30-300°C and comprises at least 0.5 vol% CO 2 ; (v) (a) subjecting a first activatable solid feedstock to a size-reduction operation in a third size-reduction apparatus in the presence of the first conditioned exhaust gas, thereby obtaining a first CO 2 -activated material, and recovering the first CO 2 -activated material; and (b) subjecting a second activatable solid feedstock to a size-reduction operation in a fourth size-reduction apparatus in the presence of the second conditioned exhaust gas, thereby obtaining a third CO 2 -activated material, and recovering the third CO 2 -activated material; (vi) (a) optionally submitting the first CO 2 -activated material to one or more further treatments where it is contacted with a CO 2 -rich gas comprising at least 0.5 vol% CO 2 outside the third size-reduction apparatus, thereby obtaining a second CO 2 -activated material, and recovering the second CO 2 -activated material; and (b) optionally submitting the third CO 2 -activated material to one or more further treatments where it is contacted with a CO 2 -rich gas comprising at least 0.5 vol% CO 2 outside the third size-reduction apparatus, thereby obtaining a fourth CO 2 -activated material, and recovering the fourth CO 2 -activated material; and (vii) producing low-carbon-footprint cement by mixing • the first and/or second CO 2 -activated material; • the third and/or fourth CO 2 -activated material; and • the cement of step (iii); wherein mixing is performed (a) by feeding the CO 2 -activated materials to the second size-reduction apparatus of step (iii) while step (iii) is being performed; and/or (b) by mixing the CO 2 -activated materials with the cement obtained in step (iii) in a mixing apparatus different from the first, second, third and fourth size-reduction apparatus.
  15. The method of claim 13 or 14 wherein the first and second activatable feedstocks are different materials.
  16. The method of any one of claims 1-13 which comprises the steps of: (i) subjecting a cement raw material to a size-reduction operation in a first size-reduction apparatus, thereby obtaining cement raw meal; (ii) subjecting the cement raw meal of step (i) to one or more pre-heating stages and to one or more calcining stages, thereby obtaining cement clinker and generating an exhaust gas comprising at least 0.5 vol% CO 2 ; (iii) subjecting the cement clinker to a size-reduction operation in a second size-reduction apparatus, thereby obtaining cement; (iv) withdrawing at least part of the exhaust gas generated in step (ii) and conditioning it by modifying one or more of temperature, pressure, CO 2 concentration and humidity, thereby obtaining a conditioned exhaust gas which has a temperature within the range of 30-300°C and comprises at least 0.5 vol% CO 2 ; (v) (a) subjecting a first activatable solid feedstock to a size-reduction operation in a third size-reduction apparatus in the presence of the conditioned exhaust gas, thereby obtaining a first CO 2 -activated material, and recovering the first CO 2 -activated material; (b) subjecting a second activatable solid feedstock to a size-reduction operation in a fourth size-reduction apparatus in the presence of the conditioned exhaust gas, thereby obtaining a third CO 2 -activated material, and recovering the third CO 2 -activated material; and (c) subjecting a third activatable solid feedstock to a size-reduction operation in a fifth size-reduction apparatus in the presence of the conditioned exhaust gas, thereby obtaining a fifth CO 2 -activated material, and recovering the fifth CO 2 -activated material; (vi) (a) optionally submitting the first CO 2 -activated material to one or more further treatments where it is contacted with a CO 2 -rich gas comprising at least 0.5 vol% CO 2 outside the third size-reduction apparatus, thereby obtaining a second CO 2 -activated material, and recovering the second CO 2 -activated material; (b) optionally submitting the third CO 2 -activated material to one or more further treatments where it is contacted with a CO 2 -rich gas comprising at least 0.5 vol% CO 2 outside the third size-reduction apparatus, thereby obtaining a fourth CO 2 -activated material, and recovering the fourth CO 2 -activated material; and (c) optionally submitting the fifth CO 2 -activated material to one or more further treatments where it is contacted with a CO 2 -rich gas comprising at least 0.5 vol% CO 2 outside the fifth size-reduction apparatus, thereby obtaining a sixth CO 2 -activated material, and recovering the sixth CO 2 -activated material; and (vii) producing low-carbon-footprint cement by mixing • the first and/or second CO 2 -activated material; • the third and/or fourth CO 2 -activated material; • the fifth and/or sixth CO 2 -activated material; and • the cement of step (iii); wherein mixing is performed (a) by feeding the CO 2 -activated materials to the second size-reduction apparatus of step (iii) while step (iii) is being performed; and/or (b) by mixing the CO 2 -activated materials with the cement obtained in step (iii) in a mixing apparatus different from the first, second, third, fourth, fifth or sixth size-reduction apparatus.

Description

Field of the invention The present invention relates to methods for integrating CO2-mediated mineral carbonation and/or activation in a cement production facility and methods for producing low-carbon-footprint cement. Background of the invention Concrete is a composite material, comprising a matrix of aggregate (typically a rocky material) and a binder (typically Portland cement or asphalt), which holds the matrix together. Concrete is one of the most frequently used building materials and is said to be the second most widely used material on earth, after water. In order to reduce the cost of concrete and the CO2 emissions generated by global cement production, much research effort has been dedicated to identifying cheap material which can be used as a filler or alternative binder to replace the binder component without (detrimentally) affecting the properties of concrete. Such secondary cementitious materials are typically called supplementary cementitious materials and are an area of broad industry interest. An example of a widely employed cement filler is limestone. A comprehensive overview of fillers in cementitious materials can be found in John, Vanderley M., et al. "Fillers in cementitious materials-Experience, recent advances and future potential." Cement and Concrete Research 114 (2018): 65-78. The production of Portland cement contributes to about 8% of world carbon dioxide emissions. According to Vanderley et al. the traditional mitigation strategies for CO2 emissions in the cement industry are not sufficient to ensure the necessary mitigation in a scenario of increasing cement demand. Currently, cement production is increasing due to a combination of increasing urbanization and replacement of old infrastructure. In an attempt to mitigate their CO2-emissions, some cement plants have started integrating carbon-capture solutions into their production. WO2011/015207A1 and WO2023/203072 describe different ways of integrating the calcium cycle into a cement production facility. WO2019/115722A1 describes flushing a stockpile or silo containing recycled concrete fines with exhaust gas of a cement production facility to clean it. WO2022/123471A1 describes introducing a carbonatable substance from an external source in the exhaust gas installation of a cement production facility. More recently, technological advances have made it possible to produce cement filler materials which are CO2-activated, such that they function as supplementary cementitious material (instead of merely being a largely inert filler). Such materials allow large cement replacement levels to be achieved. In case carbonatable materials are activated they may thus advantageously combine the primary emissions abatement from the carbon dioxide sequestered during their activation process with large secondary emissions abatement from the large cement replacement levels. Such materials are described in amongst others EP4054990B1, EP4324805B1, EP4324803B1, EP4324802B1, and US2024199485A1. By blending these materials with traditional cement, low-carbon-footprint cement can be obtained. There is a need for improved methods of integrating a carbonation stage in a cement production facility, in particular there is a need for methods which allow integration of carbonation processes or CO2-mediated activation processes with lead to the production of highly active SCMs, and have limited impact on regular cement plant operations and capacity. It is an object of the present invention to provide methods for integrating CO2-mediated mineral carbonation and/or activation in a cement production facility. It is an object of the present invention to provide methods for producing low-carbon-footprint cement. Summary of the invention In a first aspect of the invention there is provided a method for the manufacture of low-carbon-footprint cement comprising the steps of: (i) subjecting a cement raw material to a size-reduction operation in a first size-reduction apparatus, thereby obtaining cement raw meal;(ii) subjecting the cement raw meal of step (i) to one or more pre-heating stages and to one or more calcining stages, thereby obtaining cement clinker and generating an exhaust gas comprising at least 0.5 vol% CO2;(iii) subjecting the cement clinker to a size-reduction operation in a second size-reduction apparatus, thereby obtaining cement;(iv) withdrawing at least part of the exhaust gas generated in step (ii) and conditioning it by modifying one or more of temperature, pressure, CO2 concentration and humidity, thereby obtaining a conditioned exhaust gas which has a temperature within the range of 30-300°C and comprises at least 0.5 vol% CO2;(v) subjecting an activatable solid feedstock to a size-reduction operation in a third size-reduction apparatus in the presence of the conditioned exhaust gas, thereby obtaining a first CO2-activated material, and recovering the first CO2-activated material;(vi) optionally submitting the first CO2-activated material t