Highly attrition resistant and dry regenerable sorbents for carbon dioxide capture

• US 20060148642A1
• Filed: 01/04/2005
• Published: 07/06/2006
• Est. Priority Date: 01/04/2005
• Status: Active Grant

• Current Assignee: Korea Electric Power Corporation (Government of South Korea), Korea Midland Power Company Limited (Government of South Korea), Korea South-East Power Co., Ltd. (Government of South Korea), Korea Western Power Company Limited (Government of South Korea), Korea South Power Company Limited
• Original Assignee: Korea Electric Power Corporation (Government of South Korea), Korea Midland Power Company Limited (Government of South Korea), Korea South-East Power Co., Ltd. (Government of South Korea), Korea Western Power Company Limited (Government of South Korea), Korea South Power Company Limited
• Inventors: Ryu, Chong-Kul, Oh, Je-Myung, Eom, Tae-Hyoung, Lee, Joong-Beom
• Granted Patent: US 7,820,591 B2
• Time in Patent Office: Days
• US Class Current: 502/84
• CPC Class Codes: B01D 2253/10 Inorganic adsorbents
• CPC Class Codes: B01D 2253/304 Linear dimensions, e.g. particle shape, diameter
• CPC Class Codes: B01D 2253/306 Surface area, e.g. BET-specific surface
• CPC Class Codes: B01D 2253/311 Porosity, e.g. pore volume
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2259/40088 by heating
• CPC Class Codes: B01D 53/12 according to the "fluidised technique"
• CPC Class Codes: B01J 20/043 Carbonates or bicarbonates, e.g. limestone, dolomite, aragonite
• CPC Class Codes: B01J 20/06 comprising oxides or hydroxides of metals not provided for in group B01J20/04
• CPC Class Codes: B01J 20/08 comprising aluminium oxide or hydroxide; comprising bauxite
• CPC Class Codes: B01J 20/14 Diatomaceous earth
• CPC Class Codes: B01J 20/18 Synthetic zeolitic molecular sieves
• CPC Class Codes: B01J 20/28004 Sorbent size or size distribution, e.g. particle size
• CPC Class Codes: B01J 20/28011 Other properties, e.g. density, crush strength
• CPC Class Codes: B01J 20/28014 characterised by their form
• CPC Class Codes: B01J 20/28019 Spherical, ellipsoidal or cylindrical
• CPC Class Codes: B01J 20/2803 Sorbents comprising a binder, e.g. for forming aggregated, agglomerated or granulated products
• CPC Class Codes: B01J 20/28042 Shaped bodies; Monolithic structures
• CPC Class Codes: B01J 20/28045 Honeycomb or cellular structures; Solid foams or sponges
• CPC Class Codes: B01J 20/28057 Surface area, e.g. B.E.T specific surface area
• CPC Class Codes: B01J 20/28059 : being less than 100 m2/g
• CPC Class Codes: B01J 20/28069 : Pore volume, e.g. total pore volume, mesopore volume, micropore volume
• CPC Class Codes: B01J 20/3021 : Milling, crushing or grinding
• CPC Class Codes: B01J 20/3042 : Use of binding agents; addition of materials ameliorating the mechanical properties of the produced sorbent
• CPC Class Codes: B01J 20/3078 : Thermal treatment, e.g. calcining or pyrolizing
• CPC Class Codes: B01J 20/3433 : of sorbents or filter aids other than those covered by B01J20/3408 - B01J20/3425
• CPC Class Codes: B01J 20/3483 : by thermal treatment not covered by groups B01J20/3441 - B01J20/3475, e.g. by heating or cooling
• CPC Class Codes: B01J 2220/56 : Use in the form of a bed
• CPC Class Codes: B82Y 30/00 : Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: Y02C 20/40 : of CO2
• CPC Class Codes: Y10S 502/514 : Process applicable either to preparing or to regenerating or to rehabilitating catalyst or sorbent

Abstract

Disclosed herein is a dry regenerable sorbent for carbon dioxide capture from flue gas produced by fossil fuel-fired power plants including industrial boilers before being released to atmosphere or from fuel gas stream such as syngas produced by conversion of fossil fuel (e.g. gasification), by dry regenerable sorbent technology. The dry regenerable sorbent comprises: 70 wt % or less of an active component selected from solid compounds capable of being converted to metal carbonates; 70 wt % or less of a support selected from solid porous non-metallic materials capable of imparting a required specific surface area to the sorbent; and 70 wt % or less of an inorganic binder selected from cement-like, clay-like, and ceramic-like binders capable of imparting mechanical strength to the sorbent, the total weight of the solid raw materials being 100 wt %.

Claims

1. A dry regenerable sorbent for carbon dioxide capture from flue gas produced by fossil fuel-fired power plants including industrial boilers before being released to atmosphere or from fuel gas stream such as syngas produced by conversion of fossil fuel (e.g. gasification), by dry regenerable sorbent technology,

wherein the sorbent comprises:

70 wt % or less of an active component selected from solid compounds capable of being converted to metal carbonates;

70 wt % or less of a support selected from solid porous non-metallic materials capable of imparting a required specific surface area to the sorbent; and

70 wt % or less of an inorganic binder selected from cement-like, clay-like, and ceramic-like binders capable of imparting mechanical strength to the sorbent,

the total weight of the solid raw materials being 100 wt %.

2. The dry regenerable sorbent according to claim 1, wherein the active component is at least one compound selected from carbonates and bicarbonates of alkali metals and alkaline earth metals of the Group I and II of the periodic table of elements, and metal oxides capable of being converted to the carbonates and bicarbonates.

3. The dry regenerable sorbent according to claim 1, wherein the support is a hydrophilic material or a material capable of imparting hydrophilicity to the sorbent, and is at least one material selected from ceramic-like supports, including alumina, silica, magnesia, zirconia and titania, natural and synthesized zeolites, diatomaceous earth, and carbon molecular sieves (carbon nanotubes), which have a specific surface area greater than 50 m²/g.

4. The dry regenerable sorbent according to claim 1, wherein the inorganic binder is a cement-like, a clay-like or a ceramic-like binder, and is at least one binder selected from these binders.

5. The dry regenerable sorbent according to claim 4, wherein the cement binder is hydraulic cement, and is at least one material selected from calcium silicate (Portland cement), calcium aluminate cements, and gypsum (CaSO₄.2H₂O);

the clay-like binder is at least one material selected from bentonite, attapulgite (palygorskite) and sepiolite belonging to smectites, and kaolin belonging to kandites; and

the ceramic-like binder is at least one material selected from ceramics, such as alumina, silica, zirconia, titania and magnesia, ceramic sols, and pseudo-boehmite.

6. The dry regenerable sorbent according to claim 1, wherein the sorbent has a spherical shape, an average particle size of 40˜

180 μ

m, and a particle size distribution of 30˜

500 μ

m.

7. The dry regenerable sorbent according to claim 6, wherein the sorbent has a spherical shape, an average particle size of 60˜

160 μ

m, and a particle size distribution of 40˜

300 μ

m.

8. The dry regenerable sorbent according to claim 1, wherein the sorbent has a specific surface area of 5 m²/g or more, and a porosity of 30% or more.

9. The dry regenerable sorbent according to claim 1, wherein the sorbent has a carbon dioxide sorption capacity of 3% or more, and a utilization efficiency of 7% or more.

10. The dry regenerable sorbent according to claim 1, wherein the sorbent has a bulk density of 0.4 g/ml or more, and an attrition index (AI) of 90% or less;

and the sorbent is applied to a fluidized-bed or transport carbon dioxide capture process.

11. The dry regenerable sorbent according to claim 1, wherein the sorbent is used to capture and separate carbon dioxide at a temperature range of 40˜

900°

C.

12. A method for preparing a dry regenerable sorbent for carbon dioxide capture from flue gas produced by fossil fuel-fired power plants including industrial boilers before being released to atmosphere or from fuel gas stream such as syngas produced by conversion of fossil fuel (e.g. gasification), by dry regenerable sorbent technology,

wherein the method comprises the steps of:

1) adding solid raw materials of the sorbent to water with stirring to obtain a mixture (or a mixed slurry);

2) wet-comminuting and dispersing the mixture to obtain a slurry (i.e. milling and homogenization);

3) forming the slurry using a spray dryer to produce sorbent particles; and

4) pre-drying and calcining the sorbent particles to prepare the final sorbent.

13. The method according to claim 12, further comprising the steps of preparing an aqueous slurry and controlling the concentration of the slurry within the range of 15˜

50 wt %, prior to the step of forming the slurry using a spray dryer.

14. The method according to claim 13, wherein the step of preparing an aqueous slurry includes the sub-steps of:

sequentially or simultaneously adding solid raw materials to water with stirring using a mixer or homogenizer;

adding a dispersant to the mixture such that the solid raw materials are well mixed with and dispersed in the water without agglomeration; and

adding a defoamer to the mixture to remove bubbles or prevent the formation of bubbles during the stirring and homogenization.

15. The method according to claim 14, wherein the mixer or homogenizer has a speed of 50 rpm˜

30,000 rpm, and is at least one machine selected from mechanical stirrers, double-helix mixers, modular homogenizers, blenders, and ultrasonic homogenizers.

16. The method according to claim 14, wherein the dispersant contains a flow control agent;

is at least one surfactant selected from nonionic and anionic surfactants compatible with water; and

is added in an amount of 0.0110 wt %, based on the total weight of the solid raw materials.

17. The method according to claim 14, wherein the defoamer is at least one material selected from silica/silicons, silicons, metallic soaps, amido, polyethers, polyesters, polyglycols, organic phosphates, higher alcohols, and sulfuric acid fats;

and is added in an amount of 0.0011 wt %, based on the total weight of the solid raw materials of the sorbent, in order to inhibit the formation of bubbles by the use of the dispersant or by stirring or to break the bubbles.

18. The method according to claim 14, wherein the mixed slurry (or mixture) is wet-comminuted or milled using at least one mill selected from roller mills, ball mills, attrition mills, vibratory mills, planetary mills and bead mills, and homogenized to obtain a well-dispersed colloidal slurry.

19. The method according to claim 18, wherein the mixed slurry is wet-comminuted using a high-energy bead mill so as to allow the solid raw materials to have an average particle size of 1 μ

m or less, and dispersed to obtain a well-dispersed and uniform colloidal slurry.

20. The method according to claim 19, further comprising the step of adding 0.5˜

5 wt % of an organic binder to the colloidal slurry, based on the total weight of the solid raw materials of the sorbent.

21. The method according to claim 20, wherein the organic binder is at least one binder selected from polyvinyl alcohols, polyethyleneglycols, and methylcelluloses.

22. The method according to claim 20, further comprising the steps of adding a dispersant containing a flow control agent or water to control the flowability and concentration of the slurry, and adding a defoamer to the slurry.

23. The method according to claim 20, further comprising the step of removing (sieving) impurity impeding the dispersion and stability of the slurry and obstructing or plugging the spray of slurry from a nozzle or an atomizer during spray drying step, before the final step of slurry preparation or just before the step of spray drying.

24. The method according to claim 23, further comprising the step of aging the slurry for better dispersion, homogeneity and stability of the slurry, before or after the sieving step.

25. The method according to claim 23, wherein the slurry free of impurity is transferred to a spray drier and spray-dried through a nozzle or an atomizer to form a green body.

26. The method according to claim 25, further comprising the steps of pre-drying the spray-dried green body in a dryer and calcining the pre-dried green body.

27. The method according to claim 26, wherein the pre-drying is carried out at 110˜

150°

C. and the calcination is carried out at 350˜

900°

C.

28. The method according to claim 26 or 27, wherein the spray-dried or pre-dried green body is used as a raw material to prepare a sorbent in the shape of granule, extruding, pellet or honeycomb.