Methods for processing incinerator bottom ash aggregate material

Abstract

To provide a method for processing incinerator bottom ash (IBA) aggregate material formed during the combustion of domestic and comparable industrial solid waste.SOLUTION: A method for processing incinerator bottom ash (IBA) aggregate material comprises the steps of: carbonating IBA aggregate material by CO2 sequestration; providing a stabilizing additive for mixing with the carbonated IBA aggregate material; and adding the additive to the carbonated IBA material and mixing with the carbonated IBA material to form a stabilized IBA composition, wherein the additive comprises one or more components from a group (b1) and one or more components from a group (b2), wherein the group (b1) consists of aluminium chloride and at least one other metal chloride, and wherein the group (b2) consists of silica, zeolite and apatite.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for processing incinerator bottom ash (IBA) aggregate material to produce a commercially useful aggregate binder material for the production of building compositions. [Background technology]

[0002] As landfilling as a means of municipal solid waste (MSW) disposal becomes increasingly undesirable, a significant increase in the amount of MSW being sent to waste-to-energy plants such as incinerators is occurring instead. As landfilling is gradually phased out as a method of MSW disposal, there will be a demand for increased incineration capacity in the future. For example, in Scotland, it is estimated that 4,000,000 tons of MSW are landfilled each year. Furthermore, if incinerated, it is estimated that the same amount of MSW would produce approximately 750,000 tons of waste IBA and carbon dioxide (CO2).

[0003] IBA, also known as waste incineration bottom ash or "slag," generally consists of 50% amorphous mass and 50% other materials, such as glass, ceramics, slag-like materials, metals, and unburned organic matter, and is formed during the combustion of household solid waste and comparable industrial solid waste.

[0004] The properties of IBA differ from other ash types, such as "E-fly" ash and E-bottom ash, emitted from pulverized coal-fired power plants. E-fly ash is a fine powder consisting primarily of spherical glassy particles that is separated from the flue gas stream by electrostatic filters. E-bottom ash, often referred to as "boiler sand," is emitted as a "heavy" ash particle during the pulverized coal combustion process.

[0005] Currently, waste IBA is either landfilled or used as a base material in road construction or pipeline laying. However, the problem of labile heavy metals, such as copper (Cu) and molybdenum (Mo), leaching from this material and contaminating soil, groundwater, and surface water poses a significant risk to the environment.

[0006] To address this issue, carbonization of IBA or absorption or sequestration of CO2 by IBA obtained by incineration of MSW can also be carried out to change the mineralogical properties of the IBA material. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] Applied Geochemistry 17, pp. 1503-1513 (2002) [Non-patent document 2] Geosystem Engineering, Volume 15, Issue 4, Pages 305-211 (December 2102) Summary of the Invention [Problem to be solved by the invention]

[0008] For example, one study, "Carbonation Process in Municipal Solid Waste Incineration Bottom Ash and Its Effect on Copper and Molybdenum Leaching" (Non-Patent Document 1), compared the interaction and absorption of CO2 with municipal solid waste incineration (MSWI) bottom ash samples and the resulting leaching during experimental, artificial (i.e., accelerated) carbonation methods and natural carbonation (i.e., weathering). This study revealed that laboratory carbonation of MSWI bottom ash to a pH of approximately 8.3 resulted in a greater than 50% reduction in Cu leaching and a less than 3% reduction in Mo leaching. During natural weathering / carbonation, the additional adsorption sites further reduce the mobility of these contaminants, further reducing Cu and Mo leaching. However, natural carbonation is a fairly slow process, occurring over a period of months to years.

[0009] Another study, "Accelerated Carbonation of Municipal Waste Incineration Bottom Ash for CO2 Sequestration" (Non-Patent Document 2), showed that the carbonation rate of bottom ash was highest at 20C, a solid-liquid ratio of 0.2, and 20% CO2, suggesting that CO2 gas released from incinerators could be used directly as part of the accelerated carbonation process of bottom ash. [Means for solving the problem]

[0010] In one aspect of the present invention, there is provided a method for treating incinerator bottom ash (IBA), comprising the steps of: (i) carbonating an IBA aggregate material by CO2 sequestration; (ii) providing a stabilizing additive for mixing with the carbonated IBA aggregate material, the additive comprising one or more components from group (b1) and one or more components from group (b2), wherein group (b1) consists of aluminum chloride and at least one other metal chloride, and group (b2) consists of silica, zeolite, and apatite.

[0011] Optionally, the method for treating incinerator bottom ash (IBA) is: (iii) adding an additive to the carbonated IBA material to form a stabilized IBA composition.

[0012] Optionally, step (iii) comprises mechanically mixing the carbonated IBA material with the additive. Optionally, the additive is mixed with the carbonated IBA material as an aqueous solution.

[0013] Optionally, the at least one other metal chloride in group (b1) is selected from sodium chloride, potassium chloride, magnesium chloride, calcium chloride, barium chloride, ammonium chloride, strontium chloride, and combinations thereof.

[0014] Optionally, one or more components from group (b1) constitute 70.0 to 99.0 wt. % of the total weight of components (b1) and (b2). Optionally, one or more components from group (b2) constitute 1.0 to 30.0 wt. % of the total weight of components (b1) and (b2).

[0015] Optionally, the additive comprises 1 to 10 wt. % aluminum chloride, 45 to 90 wt. % of at least one other metal chloride from group (b1), and 1 to 10 wt. % of a component from group (b2).

[0016] Optionally, the additive further comprises one or more components from group (b3), group (b3) consisting of magnesium oxide, calcium oxide, and combinations thereof. Optionally, one or more components from group (b3) constitute 5 to 40% by weight of the total weight of components (b1), (b2) and (b3).

[0017] Optionally, the additive is ImmoCem® (Mega-Tech Holding BV). Optionally, the additive is RoadCem® (Mega-Tech Holding BV).

[0018] Optionally, the additive is a mixture of ImmoCem® and RoadCem®. Optionally, step (i) includes exposing the IBA aggregate material to CO2, where the CO2 is from atmospheric CO2 and / or a non-atmospheric CO2 source. Thus, the carbonation may be natural carbonation, accelerated carbonation, or a combination of both.

[0019] Optionally, step (i) comprises arranging the IBA aggregate material in rows. Advantageously, step (i) matures the IBA aggregate material, and carbonates are formed in the IBA aggregate material due to sequestration of CO2 by the IBA aggregate material.

[0020] Advantageously, step (iii) further stabilizes and immobilizes heavy metals in the carbonated IBA to form a stabilized IBA composition that reduces leaching of said heavy metals from said stabilized IBA composition.

[0021] It will be understood that the term "CO2 sequestration" refers to the removal of CO2 from the atmosphere or CO2 source by IBA, and may also be referred to as carbon sequestration by IBA carbonation. Optionally, the IBA is an IBA aggregate. Optionally, the carbonated IBA is a carbonated IBA aggregate. Optionally, the stabilized IBA composition is a stabilized IBA aggregate composition.

[0022] Optionally, the method for treating incinerator bottom ash (IBA) further comprises step (iv) of combining either the carbonated IBA aggregate material and additives of steps (i) and (ii) or the stabilized carbonated IBA aggregate composition of step (iii) with cement to form a binder composition.

[0023] Optionally, step (iv) comprises combining the carbonated IBA aggregate material and additives of steps (i) and (ii) or the stabilized carbonated IBA aggregate composition of step (iii) with cement in ratios (e.g., by weight and / or by volume) that depend on the final desired mechanical properties, such as, but not limited to, tensile strength, compressive strength, or flexural strength, of the intended building composition, element, or unit comprising said binder composition.

[0024] Optionally, the binder composition comprises carbonated IBA aggregate in an amount of 50.0 to 70.0 wt. %, based on the total weight of the binder composition; additives in an amount of 0.1 to 5.0 wt. %, based on the total weight of the binder composition; and cement in an amount of 25.0 to 69.9 wt. %, based on the total weight of the binder composition.

[0025] Optionally, the binder composition comprises stabilized carbonated IBA aggregate and cement in a 70% / 30% weight and / or volume ratio. Optionally, the method for treating incinerator bottom ash (IBA) is: (a) a pre-processing step in which IBA is crushed to form an IBA aggregate material; (b) a precursor processing step to separate ferrous and non-ferrous metals from the IBA aggregate material; (c) a precursor processing step in which the IBA aggregate material obtained from precursor step (a) or precursor step (b) is graded to a size range suitable for step (i).

[0026] Optionally, the precursor step (b) (separation of ferrous and non-ferrous metals from the IBA aggregate material) optionally comprises the sub-step of transporting the separated metals for metals recycling. Optionally, precursor step (c) (grading the IBA aggregate material) optionally comprises the substep of grading the IBA aggregate material to separate particles greater than 28 mm in size, and optionally returning said particles to precursor step (a) for further grinding.

[0027] Optionally, precursor step (c) (grading the IBA aggregate material) optionally comprises grading the IBA aggregate material to separate particles less than 28 mm, preferably less than 25 mm, for step (i).

[0028] According to a second aspect of the present invention there is provided a stabilised IBA aggregate formed according to step (iii) of the method according to the first aspect of the present invention. According to a third aspect of the present invention there is provided a binder composition comprising cement and the stabilised IBA aggregate material of the second aspect of the present invention, or a binder composition comprising cement and the carbonated IBA of step (i) and the additive of step (ii). Thus, the third aspect of the present invention is a binder composition according to step (iv) of the method according to the first aspect of the present invention.

[0029] According to a fourth aspect of the present invention there is provided a building composition comprising a binder composition according to the third aspect of the present invention. Optionally, the building composition further comprises an aggregate component in addition to the stabilized IBA aggregate of the present invention.

[0030] Optionally, the building composition is concrete. Optionally, precursor method steps (a) and (b) and (c) and associated optional sub-steps define an optional precursor stage of an IBA treatment process according to the present invention.

[0031] Optionally, method step (i) defines a first stage of an IBA treatment process. Optionally, method step (iii) defines a second stage of the IBA treatment process, which, when taken alone, is an aspect of the present invention.

[0032] Optionally, method step (iv) defines a third stage of the IBA treatment process, which, when taken alone, is a separate further aspect of the present invention. It will be appreciated that the various steps may occur at locations remote from one another.

[0033] As will be understood by those skilled in the art, various aspects of the present invention can be practiced alone or in combination with one or more other aspects. Various aspects of the present invention can optionally be provided in combination with one or more of any features of other aspects of the present invention. Also, any feature described in connection with one aspect can typically be combined alone or with other features in different aspects of the present invention. Any subject matter described herein can be combined with any other subject matter herein.

[0034] Various aspects of the present invention will now be described in detail with reference to the accompanying drawings. Further aspects, features, and advantages of the present invention will be readily apparent from the entire description, including the drawings illustrating several exemplary embodiments and implementations. The present invention is also susceptible to other different examples and embodiments, and its several details can be modified in various respects, all without departing from the scope of the present invention. Therefore, each example herein should be understood to have broad applicability and is intended to illustrate one possible way of implementing the invention, without suggesting that the scope of the present disclosure, including the claims, is limited to that example. Furthermore, the terms and expressions used herein are used for descriptive purposes only and should not be construed as limiting the scope. In particular, unless otherwise stated, dimensions and numerical values ​​contained herein are presented as examples illustrating one possible embodiment of the claimed subject matter, without limiting the disclosure to the specific dimensions and numerical values ​​described. All numerical values ​​in this disclosure are understood to be modified by "about." All singular forms of elements or any other components described herein are understood to include their plural forms, and vice versa.

[0035] Terms such as "including," "comprising," "having," "containing," or "involving," and variations thereof, are intended to be broad and include subsequently recited subject matter, equivalents, and additional unrecited subject matter, and are not intended to exclude other additives, ingredients, integers, or steps. Similarly, the term "comprising" is considered synonymous with the terms "including" or "containing" for applicable legal purposes. Thus, throughout the specification and claims, unless the context requires otherwise, the term "comprise" or variations thereof, such as "comprises" or "comprising," will be understood to mean the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers.

[0036] Any discussion of documents, statutes, materials, devices, articles and the like is included herein solely for the purpose of providing a context for the present invention. No suggestion or representation is intended that any or all of these matters form part of the prior art or were common general knowledge in the art relevant to the present invention.

[0037] In this disclosure, the words "typically" or "optionally" should be understood to be intended to indicate optional or non-essential features of the invention that are present in certain instances but that may be omitted in other instances without departing from the scope of the invention. [Brief explanation of the drawings]

[0038] [Figure 1] FIG. 1 is an exemplary flow diagram illustrating an exemplary method for treating incinerator bottom ash according to aspects of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0039] Referring to FIG. 1, there is shown a flow diagram of an exemplary method and steps for treating incinerator bottom ash (IBA) in accordance with the present invention. In optional first (a) and optional second (b) precursor processing steps, dry bulk IBA obtained as a by-product from waste incineration is crushed to form an IBA aggregate material and ferrous and non-ferrous metal particles are separated from the IBA material for metals recycling. Suitable methods of crushing and separating metal fractions from IBA material, such as magnetic and non-magnetic separation techniques, are well known and will not be described in further detail.

[0040] In a third, optional, preliminary processing step (c), the crushed IBA aggregate material resulting from the preliminary processing step (a) or (b) is graded to a suitable particle size range for further processing. Optionally, step (c) includes separating IBA aggregate material having a particle size of 28 mm or greater, more preferably even 25 mm or greater, from the remaining crushed IBA aggregate material, which can then be aged by carbonation in step (i). Optionally, oversized IBA aggregate material particles separated from the crushed IBA aggregate material are returned to be re-ground according to the preliminary step (a). Suitable methods for grading crushed IBA aggregate material and separating oversized particles are well known and will not be described in further detail.

[0041] Pre-treatment steps (a), (b) and (c), and any associated sub-steps, define an optional precursor stage of the IBA treatment process according to the present invention. In step (i), the IBA aggregate material, optionally obtained from precursor step (c), is carbonated by CO2 sequestration. In this step, the IBA aggregate material is exposed to CO2. The CO2 can be atmospheric CO2 and / or non-atmospheric CO2 obtained from another source. Thus, the carbonation can be natural, accelerated, or a combination thereof. To maximize exposure to CO2 and speed the carbonation process, the IBA material can be arranged in rows or periodically turned or moved. This step matures the IBA aggregate material and allows carbonates to form within said IBA aggregate material.

[0042] Carbonation reduces the pH of IBA in contact with water from approximately pH 12 to pH 9-10.5, and also reduces the leaching of trace metals from IBA. The carbonated IBA aggregate material formed by step (i) and any precursor steps provides a bulk aggregate material according to an embodiment of the present invention.

[0043] In a further step (iii), once the IBA aggregate material has been carbonated (i.e., "aged") to a desired degree (e.g., a pH of about 8.5) as determined based on pH measurement, the additive composition provided in intermediate step (ii) is optionally added to the carbonated IBA aggregate material to form a stabilized IBA aggregate composition. Optionally, the additive composition is mixed with the matured IBA aggregate material as an aqueous solution. The stabilized IBA aggregate composition so formed provides a stabilized IBA product according to the invention.

[0044] As shown in the figure, step (iii) can be performed as a separate step to produce a stabilized carbonated IBA aggregate composition. However, as shown in the figure, the step of adding the additive composition to the carbonated IBA aggregate material resulting from step (i) may be performed simultaneously with the addition of cement in a variation of the following step (iv), as described below. In this method, stabilization of the carbonated IBA aggregate with the additive composition occurs during mixing with cement in step (iv), rather than as a separate step (iii).

[0045] The additive composition comprises one or more components from group (b1) and one or more components from group (b2), where group (b1) consists of aluminum chloride and at least one other metal chloride, and group (b2) consists of silica, zeolite, and apatite.

[0046] In examples, the at least one other metal chloride in group (b1) is selected from sodium chloride, potassium chloride, magnesium chloride, calcium chloride, barium chloride, ammonium chloride, strontium chloride, and combinations thereof.

[0047] In an example, one or more components from group (b1) constitute 70.0 to 99.0 wt % of the total weight of components (b1) and (b2). In an example, one or more components from group (b2) constitute 1.0 to 30.0 wt % of the total weight of components (b1) and (b2).

[0048] In an example, the additive comprises 1 to 10 wt. % aluminum chloride, 45 to 90 wt. % of at least one other metal chloride from group (b1), and 1 to 10 wt. % of a component from group (b2).

[0049] Optionally, the additive further comprises one or more components from group (b3), group (b3) consisting of magnesium oxide, calcium oxide, and combinations thereof. Optionally, one or more components from group (b3) constitute 5 to 40% by weight of the total weight of components (b1), (b2) and (b3).

[0050] Further details of examples of additives are described in European Patent No. EP1349819B1, the contents of which are incorporated herein by reference. In an example, the additive composition is ImmoCem®, or RoadCem®, or a combination thereof (ImmoCem® and RoadCem® are registered trademarks of Mega-Tech Holding BV and manufactured by PowerCem Technologies BV).

[0051] Advantageously, the addition of the additive composition further stabilizes and immobilizes any heavy metals in the carbonated IBA aggregate to form a stabilized IBA aggregate composition, further reducing the leaching of said heavy metals from said stabilized IBA aggregate composition.

[0052] Optionally, the method for treating incinerator bottom ash (IBA) includes a further step (iv) of combining either the carbonated IBA aggregate material and additive composition of steps (i) and (ii) or the stabilized IBA aggregate composition of step (iii) with cement to form a binder composition.

[0053] Optionally, step (iv) comprises combining the carbonated IBA aggregate material and additives of steps (i) and (ii) or the stabilized carbonated IBA aggregate composition of step (iii) with cement in ratios (e.g., by weight and / or by volume) that depend on the final desired mechanical properties, such as, but not limited to, tensile strength, compressive strength, or flexural strength, of the intended building composition, element, or unit comprising said binder composition.

[0054] Optionally, the binder composition comprises carbonated IBA aggregate in an amount of 50.0 to 70.0 wt. %, based on the total weight of the binder composition; additives in an amount of 0.1 to 5.0 wt. %, based on the total weight of the binder composition; and cement in an amount of 25.0 to 69.9 wt. %, based on the total weight of the binder composition.

[0055] Optionally, the binder composition comprises stabilized carbonated IBA aggregate and cement in a 70% / 30% weight and / or volume ratio. The binder composition so formed, comprising cement, carbonated IBA aggregate material and additive composition, provides a binder product according to the third aspect of the invention.

[0056] In a further optional step (v), the binder composition is formed into a building composition, for example by the addition of water, and optionally by the addition of additional aggregate components, such as, but not limited to, sand or gravel.

[0057] According to a fourth aspect of the present invention there is provided a building composition comprising a binder composition according to the third aspect of the present invention. Optionally, the building composition is concrete. It will be appreciated that steps (a) and (b) and (c) of the method steps and any associated sub-steps may be considered to define precursor stages of the IBA treatment process.

[0058] Method step (i) can be considered to define the first stage of the overall IBA treatment process. Step (iii) may be considered to define the second stage of the overall IBA treatment process, which, taken in isolation, is an aspect of the present invention.

[0059] Step (iv) may be considered to define the third stage of the IBA treatment process, which, when taken in isolation, is a separate further aspect of the present invention. It will be appreciated that the various steps and stages of the overall IBA treatment process may be performed remotely and / or separately from one another.

[0060] Taken alone, the third stage defines a separate and further aspect of the present invention. Taken alone, the fourth step defines a separate and further aspect of the present invention. [a] Water, conventional aggregate * and cement † Only, [b] water, conventional aggregate * ,cement † and stabilizing additives ‡ , [c] water, conventional aggregate * ,cement † and carbonated IBA, and [d] water, conventional aggregates * ,cement † , Carbonated IBA and Stabilizing Additives ‡ In a comparative test conducted 7 days after demolding a series of molded concrete cubes containing IBA (in which approximately 60% of the conventional aggregate content was replaced by this IBA by volume), the concrete [c] (26.4 N / mm 2 ) and [d](25.9N / mm 2 ) (i.e., concrete formed in accordance with an embodiment of the present invention) had an average measured compressive strength of 29.3 N / mm 2 ) and modified conventional formulation [b] (29.0N / mm 2 ) was essentially the same as the average measured compressive strength. * Thames Valley Aggregates 540, 541, † Dragon Alfa CEM 1, ‡ PowerCem Technologies BV).

[0061] Therefore, the IBA aggregate according to the present invention has been shown to be a promising alternative to conventional aggregates in the production of concrete products. Advantageously, the use of IBA to form stabilized IBA aggregate for use in binder compositions used in the production of building compositions such as concrete reduces the amount of IBA that ends up in landfills or is used in road base materials.

[0062] Furthermore, sequestration of CO2 from the atmosphere by IBA aggregate materials removes CO2 from the atmosphere and fixes it in the IBA material. Advantageously, use of the binder composition in the production of concrete products provides a lower cost concrete compared to concrete derived entirely from conventional aggregates such as sand, gravel, and crushed stone. Additionally, by replacing conventional aggregates with stabilized IBA aggregate materials according to embodiments of the present invention, the need to mine virgin aggregates and / or cement is reduced.

Claims

1. 1. A method for treating incinerator bottom ash (IBA) aggregate material formed during combustion of domestic solid waste and comparable industrial solid waste, comprising: (i) CO ２ carbonating the IBA aggregate material by sequestration; (ii) providing a stabilizing additive for mixing with the carbonated IBA aggregate material; (iii) adding the additive to a carbonated IBA material and mixing with the carbonated IBA material to form a stabilized IBA composition, wherein the additive comprises one or more components from group (b1) and one or more components from group (b2), wherein group (b1) consists of aluminum chloride and at least one other metal chloride, and group (b2) consists of silica, zeolite, and apatite; 1. A method for processing IBA aggregate material, comprising:

2. 2. The method of claim 1, further comprising: A method for treating IBA aggregate material, wherein the additive is mixed with carbonated IBA material as an aqueous solution.

3. 3. The method for processing IBA aggregate material according to claim 1 or 2, Step (i) is a process for preparing a mixture of atmospheric CO ２ and non-atmospheric CO ２ 2. A method for treating IBA aggregate material comprising exposing said IBA aggregate material to both or one of:

4. A method for processing IBA aggregate material according to any one of claims 1 to 3, A method for processing IBA aggregate material, wherein step (i) comprises arranging said IBA aggregate material in an array.

5. The method for processing IBA aggregate material according to any one of claims 1 to 4, further comprising the step (iv) 1. A method for processing IBA aggregate material, comprising combining the carbonated IBA aggregate material of steps (i) and (ii) and said additive, or the stabilized carbonated IBA aggregate composition of step (iii), with cement to form a binder composition.

6. A method for processing IBA aggregate material according to any one of claims 1 to 5, 10. A method for treating IBA aggregate material, wherein the at least one other metal chloride in group (b1) is selected from sodium chloride, potassium chloride, magnesium chloride, calcium chloride, barium chloride, strontium chloride, and combinations thereof.

7. A method for processing IBA aggregate material according to any one of claims 1 to 6, A method for treating IBA aggregate material, wherein the one or more components from group (b1) constitute 70.0 to 99.0% by weight of the total weight of the one or more components from group (b1) and the one or more components from group (b2).

8. A method for processing IBA aggregate material according to any one of claims 1 to 7, A method for treating IBA aggregate material, wherein the one or more components from group (b2) constitute 1.0 to 30.0 wt. % of the total weight of the one or more components from group (b1) and the one or more components from group (b2).

9. A method for processing IBA aggregate material according to any one of claims 1 to 8, 10. A method for treating IBA aggregate material, wherein the additive comprises 1 to 10% by weight of aluminum chloride, 45 to 90% by weight of at least one other metal chloride from group (b1), and 1 to 10% by weight of a component from group (b2).

10. A method for processing IBA aggregate material according to any one of claims 1 to 9, the additive further comprises one or more components from group (b3), A method for treating IBA aggregate material, wherein group (b3) consists of magnesium oxide, calcium oxide, and combinations thereof.

11. 11. The method of claim 10, further comprising: A method for treating IBA aggregate material, wherein the one or more components from group (b3) constitute 5 to 40% by weight of the total weight of the one or more components from group (b1), the one or more components from group (b2) and the one or more components from group (b3).

12. A method for processing IBA aggregate material according to any one of claims 1 to 11, A method for treating IBA aggregate material, wherein the additive comprises ImmoCem®, RoadCem®, or a mixture thereof.

13. A method for processing IBA aggregate material according to any one of claims 5 to 12, 1. A method for processing IBA aggregate material, wherein the binder composition comprises carbonated IBA aggregate in an amount of 50.0 to 70.0 wt. %, based on the total weight of the binder composition; additives in an amount of 0.1 to 5.0 wt. %, based on the total weight of the binder composition; and cement in an amount of 25.0 to 69.9 wt. %, based on the total weight of the binder composition.

14. A method for processing IBA aggregate material according to any one of claims 5 to 13, A method for processing IBA aggregate material, wherein the binder composition comprises carbonated IBA aggregate and cement in a 70% / 30% weight and volume ratio, or weight or volume ratio.

15. The method for processing IBA aggregate material according to any one of claims 1 to 14 further comprises, as a precursory processing step: (a) grinding IBA to form an IBA aggregate material; (b) separating ferrous and non-ferrous metals from said IBA aggregate material; (c) grading said IBA aggregate material obtained from precursor step (a) or precursor step (b) into a size range suitable for step (i); 1. A method for processing IBA aggregate material, comprising:

16. 16. The method of processing IBA aggregate material according to claim 15, A method for processing IBA aggregate material, wherein the precursor step (b) (separating ferrous and non-ferrous metals from said IBA aggregate material) comprises the substep of transporting the separated metals for metals recycling.

17. 17. A method for treating IBA aggregate material according to claim 15 or 16, comprising: a precursor step (c) of grading the IBA aggregate material to separate particles greater than 28 mm in size; A method for processing IBA aggregate material, optionally including the sub-step of returning the particles to the precursor step (a) for further grinding.

18. 18. The method of processing IBA aggregate material according to claim 17, A method for processing IBA aggregate material, wherein a precursor step (c) comprises grading said IBA aggregate material to separate particles smaller than 28 mm, preferably smaller than 25 mm, for step (i).

19. A method for processing IBA aggregate material according to any one of claims 1 to 18, (i) CO ２ A method for treating IBA aggregate material, wherein the step of carbonating the IBA aggregate material by sequestration is carried out until the carbonation reduces the pH of the IBA aggregate material in contact with water from about pH 12 to pH 8.5-10.

5.

20. A method for processing IBA aggregate material according to any one of claims 1 to 18, (i) CO ２ A method for treating IBA aggregate material, wherein the step of carbonating the IBA aggregate material by sequestration is carried out until the carbonation reduces the pH of the IBA aggregate material in contact with water from about pH 12 to pH 9-10.

5.

21. A method for processing IBA aggregate material according to any one of claims 1 to 18 and 20, (i) CO ２ A method of treating IBA aggregate material, wherein the step of carbonating the IBA aggregate material by sequestration is carried out until the pH of the IBA aggregate material measures to about pH 8.

5.

22. A stabilized IBA aggregate material formed according to the method of processing IBA aggregate material of any one of claims 1 to 21.

23. 22. A binder composition comprising cement and the stabilized carbonated IBA aggregate material formed according to the IBA processing method of any one of claims 1 to 21.

24. A building composition comprising the binder composition of claim 23.

25. 25. The building composition of claim 24, The building composition further comprises an aggregate component in addition to the stabilized carbonated IBA aggregate material.

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