Carbon sequestration mineral admixture, and preparation method and device therefor

Abstract

A carbon sequestration mineral admixture, and a preparation method and device therefor. The method for preparing the carbon sequestration mineral admixture comprises: providing crushed solid waste; providing an activating liquid and a catalytic liquid, one or both of which is optionally in the form of micro-droplets; and contacting and reacting the activating liquid, the catalytic liquid, flue gas containing carbon dioxide, and the crushed solid waste to obtain a carbon sequestration mineral admixture, the contacting optionally being carried out under the action of an external mechanical force, wherein the activating liquid comprises one or more of a magnesium salt, an ammonium salt, an organic amine and a lower alkanol serving as an activating agent, and the catalytic liquid comprises carbonate ions and / or bicarbonate ions serving as a catalyst. The accelerated carbonization method has the advantages of a high carbonization efficiency, simple operation, and also being capable of achieving a high degree of carbonization and significantly increasing the added value of a carbonization product.

Description

Carbon sequestration mineral admixture and method and apparatus for making same TECHNICAL FIELD

[0001] The present invention relates to the technical field of comprehensive utilization of solid waste resources, and in particular to a method for preparing a carbon sequestration mineral admixture, a carbonation apparatus for carrying out the method, and a carbon sequestration mineral admixture obtained by the method. BACKGROUND

[0002] As a large steel production and infrastructure country, China produces a large amount of solid waste every year, such as about 600 million tons of waste concrete, about 100 million tons of steel slag, and a large amount of concrete slurry waste every year. At the same time, about 12 billion tons of carbon dioxide are emitted every year. Considering the huge demand for carbon reduction and sequestration, accelerated carbonation technology of solid waste has been gradually applied to treat these solid wastes, in which calcium-containing phases in solid waste react with carbon dioxide in industrial flue gas to generate calcium carbonate, thereby capturing carbon dioxide and reactivating solid waste. Accelerated carbonation of calcium-containing alkaline solid waste is currently one of the most economical and effective technical means for capturing carbon dioxide and promoting solid waste recycling.

[0003] In patents CN105800971B and WO2019115722A1, a dry carbonation method is disclosed, in which solid waste micro-powder is placed in a carbon dioxide-rich flue gas environment, and carbonation of the solid waste micro-powder and capture of carbon dioxide are achieved by controlling temperature, humidity, and other conditions. However, a dense carbonation layer is easily formed on the surface of the carbonated solid waste micro-powder, which hinders further development of carbonation. Therefore, the efficiency and degree of carbonation using this dry carbonation method are relatively low.

[0004] Chinese patent CN112125541B discloses a wet carbonation method, in which solid waste micro-powder is added to an aqueous solution, and then industrial waste gas is introduced to directly obtain solid waste carbonated micro-powder, the main components of which are calcium carbonate (calcite) and silica gel. In addition, in Chinese patents CN202310858990.1 and CN202311144356.8, calcium ions are first extracted with NH4Cl and other leaching solutions, and then calcium carbonate is obtained by wet carbonation. This wet carbonation method is less affected by the concentration of carbon dioxide in the flue gas, the carbonation layer is thin, and the carbonation efficiency and degree of carbonation are greatly improved compared with the dry carbonation method. However, a large amount of aqueous solution is required in the wet carbonation process, and after the carbonation process is completed, solid-liquid separation, product drying, and wastewater treatment are required, which is relatively complex and has high process cost.

[0005] Therefore, it is of great significance to develop an accelerated carbonation method and a corresponding carbonation device with high efficiency and simple operation, which can achieve high carbonation degree and significantly improve the added value of carbonation products.

[0006] SUMMARY

[0007] One of the purposes of the present application is to provide a method for preparing a carbon-mineralized admixture, which solves the problems of low activity and added value of solid waste, low recovery rate, and low carbonation efficiency obtained by existing carbonation technologies, and provides an accelerated carbonation method with high efficiency and simple operation, which can achieve high carbonation degree and significantly improve the added value of carbonation products.

[0008] The first aspect of the present application provides a method for preparing a carbon-mineralized admixture, comprising the following steps:

[0009] providing a pulverized solid waste;

[0010] providing an activation liquid and a catalytic liquid, one or both of which is optionally in the form of microdroplets;

[0011] contacting and reacting the activation liquid, the catalytic liquid, the flue gas containing carbon dioxide, and the pulverized solid waste to obtain the carbon-mineralized admixture, and the contacting is optionally performed under the action of an external mechanical force;

[0012] wherein the activation liquid comprises one or more of magnesium salt, ammonium salt, organic amine, and lower alkanol as an activator; and the catalytic liquid comprises carbonate ions and / or bicarbonate ions as a catalyst.

[0013] In some embodiments of the method of the present application, the solid waste contains at least 10% by weight of active substances based on the weight of calcium oxide.

[0014] In some embodiments of the method of the present application, the activation liquid contains an activator at a concentration of 0.01-10 mol / L, preferably the concentration of the activator is 0.05-5 mol / L, 0.1-1 mol / L, or 0.2-0.5 mol / L.

[0015] In some embodiments of the method of the present application, the catalytic liquid contains a catalyst at a concentration of 0.01-10 mol / L, preferably the concentration of the catalyst is 0.01-5 mol / L, 0.1-1 mol / L, or 0.1-0.5 mol / L, for example 0.05 mol / L, 0.1 mol / L, 0.2 mol / L, or 0.5 mol / L.

[0016] In some embodiments of the method of the present application, wherein the catalyst is a carbonate or bicarbonate; or the catalyst is obtained by the reaction of an alkali metal hydroxide, aqueous ammonia or an organic amine with carbon dioxide.

[0017] In some embodiments of the method of the present application, wherein the droplet diameter of the microdroplets is in the range of 100 nm to 3000 μm.

[0018] In some embodiments of the method of the present application, wherein the weight ratio of the pulverized solid waste to the activating liquid is 1: (0.001 to 1); and / or the weight ratio of the pulverized solid waste to the catalyzing liquid is 1: (0.001 to 1).

[0019] In some embodiments of the method of the present application, wherein in the step of contacting the activating liquid, the catalyzing liquid, the flue gas containing carbon dioxide and the pulverized solid waste, the activating catalyzing liquid containing the activating agent and the catalyst is first obtained, and then the flue gas containing carbon dioxide and the pulverized solid waste are contacted therewith; or the activating liquid is first mixed with the pulverized solid waste, and then the catalyzing liquid and the flue gas containing carbon dioxide are contacted with the resulting mixture.

[0020] In some embodiments of the method of the present application, wherein the concentration of carbon dioxide in the flue gas containing carbon dioxide is in the range of 5 to 100%; and / or the feeding rate of the flue gas is controlled in the range of 0.1 to 100 L / min per kg of the pulverized solid waste.

[0021] In some embodiments of the method of the present application, wherein the external mechanical force is from one or more of a ball milling device, a stirring device, a micro-vibration device.

[0022] In some embodiments of the method of the present application, wherein the activating liquid contains a magnesium salt, and the activating liquid, the catalyzing liquid, the flue gas containing carbon dioxide and the pulverized solid waste are contacted and reacted at a temperature in the range of 20 to 100 °C, preferably at a temperature in the range of room temperature to 80 °C.

[0023] In some embodiments of the method of the present application, wherein the activating liquid contains one or more of a lower alkanol, an organic amine, an ammonium salt, or the activating liquid contains a lower alkanol and the catalyzing liquid is obtained by the reaction of aqueous ammonia or an organic amine with carbon dioxide.

[0024] The second aspect of the present application provides an apparatus for preparing a carbon-mineral-doped material, the apparatus comprising a flue gas providing unit, an activating liquid and a catalyzing liquid storing and processing unit, and a carbonation reaction unit.

[0025] In some embodiments of the apparatus of the present application, wherein the flue gas providing unit provides the flue gas in the form of a compressed liquid.

[0026] In some embodiments of the apparatus of the invention, wherein the activation liquid and catalytic liquid storage and processing unit provides microdroplets of one or both of the activation liquid and the catalytic liquid.

[0027] A carbonated mineral admixture is provided by the third aspect of the invention, which is obtained by the method of any one of the above aspects, or is prepared by the apparatus of the above aspects.

[0028] In some embodiments of the carbonated mineral admixture of the invention, wherein at least 60 wt% of calcium (by weight of calcium oxide) is present in the form of calcium carbonate.

[0029] In some embodiments of the carbonated mineral admixture of the invention, wherein the calcium carbonate is present in one or more of the forms of calcite, magnesian calcite, aragonite, vaterite, other partially crystalline calcium carbonate, amorphous calcium carbonate.

[0030] In some embodiments of the carbonated mineral admixture of the invention, wherein the other partially crystalline calcium carbonate has a crystallinity of less than 80%.

[0031] In some embodiments of the carbonated mineral admixture of the invention, wherein the carbonated mineral admixture contains amorphous silica gel, alumina gel or silica-alumina gel.

[0032] The above technical solutions of the invention have at least the following advantages.

[0033] 1. The method for preparing a carbonated mineral admixture provided by the invention involves accelerated carbonization of solid waste, which has the advantages of faster carbonization speed, more absorbed carbon dioxide, higher activity of carbonization products, and higher added value, and the method is simple to operate without the need for complex solid-liquid separation, product drying, wastewater treatment and other processes, thus significantly reducing the process cost compared to traditional wet carbonization processes. In particular, the carbonization method provided by the invention uses specially selected activators and catalysts to participate in the carbonization reaction in the form of ultrafine droplets, which can easily control the product composition and morphology and accelerate the carbonization process.

[0034] 2. The carbon sequestration mineral admixture obtained by the accelerated carbonation process provided herein mainly comprises calcium carbonate, which can have various morphologies, lower crystallinity or even amorphous, and also contains other highly polymerized amorphous gels (e.g. silica gel, alumina gel or silica-alumina gel). These calcium carbonates have low thermodynamic stability, high solubility, and various morphologies, which can (1) exhibit higher activity in the cement concrete system, for example, provide higher concentrations of calcium ions and / or carbonate ions, thereby promoting the formation of monocarboaluminate in the cement hydration product, thereby making the concrete structure more compact; or (2) play a specific role, for example, fibrous aragonite whiskers, which can be used as microfibers in new concrete to enhance tensile properties.

[0035] 3. The carbonation equipment for carrying out the carbonation process of the solid waste described above has greater flexibility compared to the carbonation equipment of the prior art, and each unit can be fully adjusted according to the process and product requirements. BRIEF DESCRIPTION OF DRAWINGS

[0036] The above and other objects and features of the present disclosure will become apparent from the following description of the disclosure when taken in conjunction with the accompanying drawings.

[0037] FIG. 1 is a scanning electron microscope image of the carbon sequestration mineral admixture obtained according to the method described in Example 1 of the present application.

[0038] FIG. 2 is a corresponding equipment used according to the method described in Example 2 of the present application.

[0039] FIG. 3 is a scanning electron microscope image of the carbon sequestration mineral admixture obtained according to the method described in Example 2 of the present application.

[0040] FIG. 4 is a scanning electron microscope image of the carbon sequestration mineral admixture obtained according to the method described in Example 3 of the present application.

[0041] FIG. 5 is a transmission electron microscope image of the carbon sequestration mineral admixture obtained according to the method described in Example 4 of the present application.

[0042] FIG. 6 is a scanning electron microscope image of the carbon sequestration mineral admixture obtained according to the method described in Comparative Example 2 of the present application. DETAILED DESCRIPTION

[0043] Although the present application provides reference to various embodiments, those skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the application. The reference to various embodiments does not limit the scope of the claims appended hereto. Additionally, none of the embodiments set forth in the present application are intended to be limiting, and merely set forth some of the many possible embodiments of the present application.

[0044] The methods and materials described below are those that are used in the practice or testing of the present application, unless otherwise expressly indicated otherwise. Methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety. It should be understood that any reference to publication, patent, patent application, or other document herein is not an admission that the document is part of the prior art or that it is specifically incorporated by reference.

[0045] Definitions

[0046] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as those commonly understood by one of ordinary skill in the art to which this application belongs. If there is a conflict between the definitions in this text, including definitions in the incorporated documents, the definitions in this text, including definitions in this section, prevail.

[0047] Throughout this application, where a product is described as having, including, or comprising specific components, or where methods are described as having, including, or comprising specific steps, it is contemplated that the product of the present teachings can also consist essentially of, or consist of, the recited components, and that the methods of the present teachings can also consist essentially of, or consist of, the recited steps.

[0048] In this application, where an element or component is said to be included in the presence of, or selected from the group consisting of, a list of recited elements or components, it is contemplated that the element or component can be any one of the recited elements or components, or the element or component can be selected from the group consisting of two or more of the recited elements or components. Further, it is contemplated that elements and / or features of a composition or method described herein can be combined in a variety of ways, even if not explicitly described, without departing from the spirit and scope of the present teachings.

[0049] It should be understood that the order of steps or order of performing certain actions can be changed while still falling within the scope of the application. Further, the various steps or actions can take place simultaneously, concurrently, or at least in part, unless expressly stated otherwise.

[0050] Unless specifically stated otherwise, the term "about," as used herein when referring to a numerical value, denotes and includes the specific numerical value itself, unless otherwise specifically stated. As used herein, the term "about" means ±10%, ±7%, ±5%, ±3%, ±1%, or ±0% of the recited value, unless otherwise stated or inferred.

[0051] In the present teachings, the expression "optional" means that both embodiments in which the feature (e.g., component, step, etc.) defined by the term is present and in which it is not present are contemplated.

[0052] In the present invention, any range of values encompasses all values within the range and should be interpreted in the same way as a statement that the endpoints of the range are included within the range. For example, a disclosure in the present specification of a range of 1 to 5 should be considered to mean any subrange within the range of 1 to 5: 1-5, 1-4, 1-3, 1-2, 2-5, 2-4, 2-3, 3-5, 3-4, and 4-5.

[0053] The term "carbonation mineral admixture" as used herein refers to an inorganic mineral material added at the time of preparing concrete, which changes the properties of fresh concrete and hardened concrete, and is obtained by converting at least a part of calcium oxide into calcium carbonate through a carbonation reaction with carbon dioxide using solid waste as a raw material.

[0054] The term "solid waste" as used herein refers to calcium-containing alkaline solid waste generated in industries such as construction and metallurgy. Examples of solid waste in the present invention can include waste concrete, waste slurry of a concrete mixing plant, steel slag, carbide slag, high calcium fly ash, magnesium slag, and mixtures thereof, and the like. The solid waste used contains at least 10 wt% of calcium-containing active material based on the weight of calcium oxide.

[0055] The "carbon dioxide-containing flue gas" in the present invention can be exhaust gas from industries such as metallurgy, coal, natural gas, or chemical industry, which is usually a mixture of gas and soot, and is one of the important objects to be controlled for air environmental management.

[0056] The term "lower alkanol" as used herein refers to an organic compound having the structure of R-OH, in which a hydrogen atom in an alkane is substituted with OH, and R can be a lower alkyl group having 1 to 6 carbon atoms. Examples of lower alkyl groups include methyl, ethyl, propyl (e.g., n-propyl and isopropyl), and butyl (e.g., n-butyl, isobutyl, sec-butyl, t-butyl).

[0057] The term "organic amine" as used herein refers to a derivative in which a hydrogen atom in an NH3 molecule is substituted with a hydrocarbon group. Examples of organic amines in the present invention can include chain polyamines, dibasic amines, sterically hindered amines, alcohol amines, or amides, and the like.

[0058] The term "silica gel", "alumina gel", or "silico-alumina gel" as used herein refers to a high-polymerization-degree gel in which silicates, aluminates, or silico-aluminates are polymerized after a carbonation reaction, and almost only contain silicon, aluminum, and oxygen.

[0059] The term "room temperature" as used herein generally refers to 20 to 30°C, for example, 25°C.

[0060] The solid waste generated at present, such as waste concrete, steel slag, concrete slurry waste and the like, contains one or more calcium-containing phases such as calcium hydroxide, hydrated calcium silicate, calcium silicate and the like. It is found through experiments that these calcium-containing phases can capture 5-30% of their own weight of carbon dioxide. At the same time, the carbonated product can be used as a concrete mineral admixture, thereby reducing the use of cement clinker to achieve the purpose of further reducing carbon emissions.

[0061] Calcium carbonate is the main product after carbonation of calcium-containing alkaline solid waste. Calcium carbonate includes different crystal forms such as calcite, aragonite, vaterite and amorphous calcium carbonate. Different forms of calcium carbonate exhibit different morphologies and thermodynamic stabilities. Calcite is approximately cubic and is the most common crystal form with the highest thermodynamic stability. Aragonite exhibits a needle-like morphology and has a lower stability than calcite. Vaterite exhibits a spherical morphology and has a lower stability. Amorphous calcium carbonate does not exhibit a specific morphology and has the lowest stability. In addition, when impurity ions such as magnesium ions are added to calcite, magnesium-containing calcite can be formed, which has a morphology similar to a spindle and has a higher stability. In addition, different crystal forms of calcium carbonate can also have differences in crystallinity. As the crystallinity decreases, the reactivity of calcium carbonate increases.

[0062] When calcite is used as a concrete admixture, it is limited by low solubility, low content of aluminum phase in the cement system and other factors, and cannot fully play a role. Aragonite, magnesium-containing calcite and the like have unique needle-like or spindle-like physical forms, which are microfibers that can enhance the crack propagation resistance of the concrete matrix and improve the strength of the concrete, and have high added value. At the same time, vaterite has a spherical morphology and can improve the fluidity of concrete. Compared with crystalline calcium carbonate, amorphous calcium carbonate and other calcium carbonates with low crystallinity have higher solubility and can more actively participate in cement reactions, and have higher reactivity. Therefore, in the present application, the preparation of these functional calcium carbonates based on accelerated carbonation has higher economic and environmental benefits than the simple carbonation of calcite. At the same time, alkaline solid waste is often a material containing silicon and aluminum, which will undergo polymerization after carbonation to form amorphous silica gel, aluminum gel or silica-aluminum gel, thereby further improving the reactivity of the product.

[0063] The method for preparing a carbon-mineral admixture provided by the present application comprises the following steps:

[0064] providing crushed solid waste;

[0065] providing an activation liquid and a catalytic liquid, one or both of which is / are optionally in the form of microdroplets;

[0066] contacting and reacting the activation liquid, the catalytic liquid, the flue gas containing carbon dioxide, and the pulverized solid waste, optionally under the action of an applied mechanical force, to obtain the carbon-mineralized admixture;

[0067] wherein the activation liquid comprises one or more of a magnesium salt, an ammonium salt, an organic amine, and a lower alkanol as an activating agent; and the catalytic liquid comprises carbonate ions and / or bicarbonate ions as a catalyst.

[0068] In some embodiments, the solid waste can be pulverized and ground to obtain solid waste micropowder, with a particle size controlled to be less than 150 pm, preferably less than 100 pm, 90 pm, 80 pm, 70 pm, 60 pm, 50 pm, 40 pm, 30 pm, 20 pm, or 10 pm.

[0069] In other embodiments, the diameter of the solid waste can be controlled to be less than 20 cm, preferably less than 18 cm, 15 cm, 10 cm, 7 cm, 6 cm, 5 cm, 4 cm, 3 cm, 2 cm, or 1 cm, and a ball milling technique can be used as an applied mechanical force to adjust the reaction process to gradually form the solid waste micropowder during carbonization.

[0070] In some embodiments, the solid waste used in the above method contains at least 10 wt% of calcium-containing active substances based on the weight of calcium oxide, and the amount of calcium-containing active substances can be, for example, at least 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, or more.

[0071] The present inventors have found that certain activating agents can enable the production of specific functional calcium carbonate. An aqueous solution of the activating agent can generally be used in the present method.

[0072] The activating agent used in the present method can be one or more of a magnesium salt, an ammonium salt, an organic amine, and a lower alkanol, preferably these activating agents have good solubility in water. For example, the magnesium salt can be one or more of magnesium sulfate, magnesium chloride, magnesium nitrate, or magnesium silicate; the ammonium salt can be, for example, one or more of ammonium sulfate, ammonium bisulfate, ammonium chloride, ammonium carbonate, ammonium bicarbonate; the organic amine can be, for example, a chain polyamine, a dibasic amine, a sterically hindered amine, an alcohol amine, or an amide; and the lower alkanol can be, for example, methanol, ethanol, propanol (e.g., n-propanol and isopropanol), and butanol (e.g., n-butanol, isobutanol, sec-butanol, t-butanol).

[0073] In some embodiments, the activating solution can contain an activator at a concentration of 0.01-10 mol / L, preferably at a concentration of 0.1-4 mol / L, 0.2-3 mol / L, 0.5-2 mol / L, for example 0.05 mol / L, 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.7 mol / L, 1.8 mol / L, 1.9 mol / L, 2.0 mol / L, 2.5 mol / L, 3 mol / L, 3.5 mol / L, 4 mol / L, 4.5 mol / L, 5 mol / L, 6 mol / L, 7 mol / L, 8 mol / L, 9 mol / L, or 10 mol / L, or a range between any two of them.

[0074] In some embodiments, the weight ratio of the pulverized solid waste to the activating solution is 1:(0.001-1), preferably 1:(0.01-5), 1:(0.01-4), 1:(0.01-3), 1:(0.01-2), 1:(0.01-1), 1:(0.05-1), 1:(0.05-0.5), 1:(0.05-0.6), 1:(0.05-0.8), 1:(0.01-0.1), specifically 1:0.01, 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.15, or 1:0.2, or a range between any two of them.

[0075] In the method of the present application, the catalyst containing carbonate ions and / or bicarbonate ions can directly provide a high concentration of reactant ions (carbonate and / or bicarbonate) at the initial stage of the reaction; after the reaction of the reactant ions and the alkaline reactant in the solid waste, the alkalinity of the solution is increased, which is conducive to the progress of the carbonation reaction. At the same time, with the help of the high specific surface area of the catalyst microdroplets, the carbon dioxide gas in the flue gas entering the reactor can be dissolved in the microdroplets in time, thereby maintaining a high concentration of reactant ions (carbonate and / or bicarbonate) that can participate in the reaction.

[0076] In some embodiments, the catalyst can be a carbonate or bicarbonate. In other embodiments, the catalyst can be a product obtained by the reaction of an alkali metal hydroxide, aqueous ammonia or an organic amine with carbon dioxide, or a product containing carbonate and / or bicarbonate produced by the reaction of carbon dioxide with other basic substances.

[0077] In some embodiments, the catalyst can be included in the catalytic liquid at a concentration of 0.01-10 mol / L, preferably at a concentration of 0.01-9 mol / L, 0.05-8 mol / L, 0.1-7 mol / L, 0.1-5 mol / L, 0.2-4 mol / L, 0.3-5 mol / L, 0.4-3 mol / L, 0.5-2 mol / L, for example 0.05 mol / L, 0.1 mol / L, 0.15 mol / L, 0.2 mol / L, 0.25 mol / L, 0.3 mol / L, 0.35 mol / L, 0.4 mol / L, 0.45 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.4 mol / L, 1.5 mol / L, 1.6 mol / L, 1.7 mol / L, 1.8 mol / L, 1.9 mol / L, 2.0 mol / L, 2.5 mol / L, 3 mol / L, 3.5 mol / L, 4 mol / L, 4.5 mol / L, 5 mol / L, 6 mol / L, 7 mol / L, 8 mol / L or 9 mol / L, or a range between any two of them.

[0078] In some embodiments, the weight ratio of the pulverized solid waste to the catalytic liquid can be 1:(0.001-1), preferably 1:(0.01-5), 1:(0.01-4), 1:(0.01-3), 1:(0.01-2), 1:(0.01-1), 1:(0.05-1), 1:(0.05-0.5), 1:(0.05-0.6), 1:(0.05-0.8), 1:(0.01-0.1), specifically 1:0.01, 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.15 or 1:0.2, or a range between any two of them.

[0079] In some embodiments, the activation solution and / or the catalyst solution can preferably be in the form of microdroplets having a diameter of 100 nm to 3000 μm, preferably 100 nm to 1000 μm, such as 100 nm, 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 800 nm, 900 nm, 1000 nm, 10 μm, 20 μm, 50 μm, 100 μm, 200 μm, 500 μm, 1000 μm, 1200 μm, 1400 μm, 1600 μm, 2000 μm, 2200 μm, 2400 μm, 2600 μm, 2800 μm, 3000 μm, or a range between any two of them.

[0080] The microdroplets of the activation solution and / or the catalyst solution can be formed, for example, by atomization or the like, which can be performed using any mature commercial atomization device, such as an ultrasonic atomizer or a common atomizer.

[0081] In the method of the present application, the activation solution and / or the catalyst solution can also be used directly in the carbonization reaction without forming microdroplets.

[0082] In some embodiments, in the step of contacting the activation solution, the catalyst solution, the flue gas containing carbon dioxide, and the pulverized solid waste, an activation and catalyst solution is first obtained, and then contacted with the flue gas containing carbon dioxide and the pulverized solid waste.

[0083] In other embodiments, the activation solution is first mixed with the pulverized solid waste, and then the catalyst solution and the flue gas containing carbon dioxide are contacted with the resulting mixture.

[0084] In the method of the present application, when the activation agent and the catalyst do not react with each other, the mixing method is not particularly limited, for example, (1) the catalyst solution and the activation solution are mixed together, and then microdroplets are formed and provided into the reaction vessel; (2) the catalyst solution and the activation solution are separately formed into microdroplets and introduced into the reaction vessel, or (3) the activation solution is first mixed directly with the solid waste, and then the catalyst solution is atomized and introduced into the reaction vessel. When the catalyst solution and the activation solution can react with each other, the activation solution can be first mixed directly with the solid waste, and then the catalyst solution in the form of microdroplets is introduced.

[0085] In the method of the present application, the content of carbon dioxide in the flue gas is not particularly limited. In some embodiments, the concentration of carbon dioxide in the flue gas containing carbon dioxide ranges from 5% to 100%, such as 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%, or a range between any two of them.

[0086] In some embodiments, the rate of the flue gas introduced is controlled to be in the range of 0.1 to 100 L / min per kg of the pulverized solid waste, preferably in the range of 1 to 50 L / min, 1 to 10 L / min, for example 500 ml / min, 1 L / min, 1.5 L / min, 2 L / min, 3 L / min, 4 L / min, 5 L / min, or in the range between any two of them.

[0087] The external mechanical force can be from one or more of a ball milling device, a stirring device, a micro-vibration device, etc. The external mechanical force can affect the crystallization of the product, favoring the formation of a low-crystallinity product or an amorphous product, while favoring the avoidance of the deposition of carbonized products, and favoring the promotion of the reaction.

[0088] In some embodiments of the method of the present application, the activation liquid comprises a magnesium salt, and the activation liquid, the catalytic liquid, the flue gas containing carbon dioxide, and the pulverized solid waste are contacted and reacted at a temperature in the range of 20 to 100 °C, preferably at a temperature in the range of room temperature to 80 °C, and more preferably at a temperature in the range of 60 to 80 °C. In these embodiments, a larger proportion of the calcium carbonate in the product can be in the form of aragonite.

[0089] For example, the aragonite content in the resulting product calcium carbonate can be at least 50 wt%, 60 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, or 90 wt%, or higher.

[0090] In some embodiments of the method of the present application, a calcium carbonate product with vaterite as the main component can also be obtained. For example, in one embodiment, the activation liquid can comprise a lower alkanol and an ammonium salt. In another embodiment, the activation liquid comprises a lower alkanol and the catalytic liquid is obtained by the reaction of ammonia or an organic amine with carbon dioxide, or the catalytic liquid comprises a product containing carbonate and / or bicarbonate produced by the reaction of carbon dioxide with other basic substances.

[0091] In embodiments of the method of the present application, the reaction temperature, humidity, etc. are not intentionally controlled in most cases, unless otherwise specified, thus greatly simplifying the reaction process and related operations.

[0092] Apparatus for preparing carbon-mineral-mineral admixture

[0093] The previous equipment for accelerating carbonization mainly includes: (1) a flow-through carbonization box without temperature, humidity and carbon dioxide concentration control functions, (2) a carbonization environment box with temperature, humidity and carbon dioxide concentration control functions, and (3) a pressurized carbonization kettle capable of further increasing the carbon dioxide partial pressure and improving the carbonization degree. Among them, the first kind of equipment consumes gas and has low carbonization degree; the second kind of equipment consumes electricity and has high maintenance cost; the third kind of equipment has high operation difficulty and safety hazard.

[0094] To solve the above problems of the previous carbonization equipment, the present application also provides an equipment for preparing a carbon sequestration mineral admixture, which comprises a flue gas providing unit, an activation liquid and catalytic liquid storage and processing unit, and a carbonization reaction unit. The equipment provided by the present application can be used to perform the above-mentioned method for preparing a carbon sequestration mineral admixture of the present application.

[0095] In the equipment provided by the present application, the flue gas providing unit is used to provide flue gas containing carbon dioxide as a reactant. In some embodiments, the flue gas providing unit provides flue gas in the form of compressed liquid. Among them, the flue gas providing unit includes a flue gas transfer unit, which is used to compress and liquefy industrial flue gas containing carbon dioxide to a transfer tank to provide carbon dioxide for subsequent activation liquid and catalytic liquid preparation and / or carbonization reaction.

[0096] The activation liquid and catalytic liquid storage and processing unit is used to prepare and optionally process the activation liquid and the catalytic liquid to form microdroplets for subsequent carbonization reaction.

[0097] The carbonization reaction unit is used for the gas-solid-liquid reaction between the pulverized solid waste, the activation liquid, the catalytic liquid, and the flue gas containing carbon dioxide.

[0098] In some embodiments, the flue gas transfer unit can include pumps, heat exchangers, compressors, liquefied storage tanks and other devices. The flue gas can be stored in the liquefied storage tank for storage and transfer, and then provided to the subsequent part for use.

[0099] In some embodiments, the flue gas can also be provided directly in the form of gas to the subsequent part without flue gas transfer.

[0100] In some embodiments, the activation liquid and catalytic liquid storage and processing unit includes liquid storage and processing devices. Among them, the liquid storage device can be divided into an activation liquid storage device and a catalytic liquid storage device, both of which are connected to a microdroplet generator and can be processed simultaneously or sequentially to provide microdroplets of activation liquid and / or catalytic liquid. Among them, the activation liquid storage device is used to prepare and store the activation liquid, and the catalytic liquid storage device is used to prepare and store the catalytic liquid.

[0101] In some embodiments of the device of the present application, the carbonation reaction unit comprises a microdroplet / liquid inlet, a flue gas inlet, a mechanical reactor, and an in / out feed port, and optionally a temperature control module for controlling the temperature in the reaction vessel. Among them, the microdroplet / liquid inlet provides an entrance for the activated liquid and catalytic liquid in liquid form into the reaction vessel, and can also provide an entrance for the activated liquid / catalytic liquid that does not need to be in the form of microdroplets into the reaction vessel. The in / out feed port can realize the feeding and discharging of solid waste. The mechanical reactor can be equipped with one or more of a stirrer or a ball mill.

[0102] In some embodiments, the inlets of all microdroplets, liquids, and flue gases can be one-way inlets, thereby forming an increased micro-pressure inside the carbonation reaction vessel.

[0103] In some embodiments, the flue gas inlet can have a liquefied flue gas inlet and / or a gaseous flue gas inlet, the liquefied flue gas inlet providing an entrance for the flue gas transferred from the liquefied storage tank into the reaction vessel, and the gaseous flue gas inlet providing an entrance for the flue gas not stored in the liquefied transfer tank into the reaction vessel in gaseous form.

[0104] The device for preparing carbon-mineral admixture of the present application fully considers that (1) the emission of industrial high-temperature flue gas and the asynchronization of carbonation production can directly provide the generated flue gas, or the flue gas can be liquefied and stored first and then provided to the subsequent step when needed; (2) different catalytic liquids and activated liquids can realize flexible feeding mode, for example, catalytic solution and activated solution that can react with each other need to be fed separately; in this case, the activated solution can be directly fed into the reaction unit without treatment and mixed with the solid waste micro-powder in advance; if the catalytic solution and the activated solution do not react with each other, their feeding mode is not limited, they can be fed separately or mixed and then fed, as long as the feeding time of the activated solution is not later than that of the catalytic solution; (3) the device can promote the thorough progress of carbonation reaction, for example, the device can feed carbon dioxide gas into the carbonation reaction unit to supplement the carbonate ions in the microdroplets in time and form a micro-pressure environment to further promote carbonation; it can also provide micro-vibration and strong inter-particle mechanical collision force by providing external mechanical force to avoid the carbonation product covering the surface of the solid, thereby promoting carbonation; and (4) each unit can be fully adjusted according to the product demand, and the operability and flexibility of the device are greater.

[0105] Carbon-mineral admixture

[0106] The present application also provides a carbon-mineral admixture, which can be obtained by the aforementioned method of the present application or prepared by the above-mentioned device.

[0107] In some embodiments, the carbon-sequestering mineral admixture comprises at least 60 wt% calcium (as CaO) in the form of calcium carbonate, preferably at least 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt% or more.

[0108] The calcium carbonate can exist in one or more of aragonite, magnesio calcite, vaterite, other partially crystalline calcium carbonate, amorphous calcium carbonate. A small amount of calcium carbonate in calcite form can also be present.

[0109] The calcium carbonate can have a crystallinity of 100% or less, preferably less than 80%, for example less than 70%, less than 60%, less than 50%, less than 40%, less than 30% or less than 20%.

[0110] The carbon-sequestering mineral admixture provided herein contains amorphous silicate, aluminate or aluminosilicate gels, which can further improve the reactivity of the product. In some embodiments, the content of these amorphous gels can be at least 5 wt% of the resulting product.

[0111] The mineral admixture of the present application is dominated by calcium carbonate in different forms and low crystallinity or even amorphous, while containing other high polymerization degree amorphous gels such as silica gel, alumina gel and aluminosilicate gel.

[0112] These calcium carbonates have low thermodynamic stability, high solubility and rich morphologies, which can (1) exhibit higher activity in cement concrete systems, for example, provide higher concentrations of calcium ions and carbonate ions, promote the formation of single-carbon type calcium aluminate hydrate in cement hydration products, and thus make the concrete structure denser; and (2) have specific functionality, for example, fibrous aragonite whiskers can be used as microfibers in new concrete, thereby enhancing the tensile properties.

[0113] In contrast, the mineral admixture obtained using the traditional accelerated carbonation technology is mainly calcium carbonate in the form of calcite as the main form and a small amount of amorphous gel. Among them, calcite has the highest thermodynamic stability and the lowest activity among all possible forms of calcium carbonate. Taking common solid waste such as waste concrete, waste concrete slurry and steel slag as an example, after carbonation using the traditional accelerated carbonation technology, calcite usually accounts for 60-80% of the total carbonation product. The calcite in this product cannot exhibit activity in the cement concrete system, so the overall reactivity of the product is low. Therefore, the mineral admixture provided herein has significantly improved reactivity.

[0114] Specific embodiments of the present application are described below with reference to the accompanying drawings. It is to be understood that various modifications can be made without departing from the scope of the present application, which is set forth in the appended claims. The following examples are provided merely to illustrate.

[0115] Embodiments

[0116] Materials

[0117] The solid waste feedstock used in the following examples is waste slurry from a concrete mixing plant, which has a calcium oxide content of about 40 wt% as determined by X-ray fluorescence test; the flue gas containing carbon dioxide is flue gas from a cement plant.

[0118] Other reagents, activators, catalysts, solvents and additives used in this example are commercially available.

[0119] Apparatus

[0120] Figure 2 shows the apparatus 100 used in the following examples. Therein, a flue gas providing unit 10 is used to provide flue gas 11 containing carbon dioxide as a reactant, which is treated via a pump 12, a heat exchanger 13, a compressor 14 and stored in a liquefied storage tank 15 in liquid form.

[0121] The activation liquid and catalyst liquid storage and treatment unit 20 comprises an activation liquid storage device 21 and a catalyst liquid storage device 22, both of which are in communication with a microdroplet generator 23 via optional valves. The liquefied flue gas from the liquefied storage tank 15 can be provided to the activation liquid storage device 21 and / or the catalyst liquid storage device 22 for preparation of activation liquid and catalyst liquid. The prepared activation liquid and catalyst liquid can be provided to the subsequent carbonation reaction unit 30 in the form of droplets via the microdroplet generator.

[0122] The carbonation reaction unit 30 comprises a microdroplet / liquid inlet 31, a liquefied flue gas inlet 32, a gaseous flue gas inlet 33, a mechanical reactor 34 and an in / out feed port 35, and optionally a temperature control module for controlling the temperature in the reaction vessel. The pulverized solid waste feedstock is fed into the carbonation reaction unit 30 via the in / out feed port 35 for subsequent reaction. The liquefied flue gas from the liquefied storage tank 15 can be provided to the liquefied flue gas inlet 32, and the flue gas in gaseous form can also be provided directly to the gaseous flue gas inlet 33 for carbonation reaction. The product after reaction is still discharged via the in / out feed port 35.

[0123] Preparation Examples

[0124] Example 1

[0125] A method for preparing high-activity carbon-mineral admixture using flue gas for rapid carbonation, comprising the following steps:

[0126] (1) Selecting the waste slurry of concrete mixing station, precipitating and drying to obtain waste slurry material;

[0127] (2) Using industrial alcohol to prepare an ethanol solution with a mass fraction of 50% (molar concentration of about 10 mol / L); preparing an ammonium bicarbonate solution with a concentration of 1 mol / L; the weight of the ethanol solution is 0.1 kg, and the weight of the ammonium bicarbonate solution is 0.1 kg.

[0128] (3) Pouring 2 kg of waste slurry material into a 5L horizontal stirrer, using the horizontal stirrer as a reaction container, and stirring at a speed of 15 rpm.

[0129] (4) Using a microdroplet generator to process the ethanol solution and the ammonium bicarbonate solution into microdroplets, obtaining two kinds of microdroplets with an average droplet diameter of about 10 μm, synchronously introducing the two kinds of microdroplets into the reaction container loaded with the waste slurry material, controlling the introduction speed to be 5 g / min, simultaneously introducing waste gas containing carbon dioxide, controlling the waste gas flow to be 3 L / min, and controlling the total introduction time to be 40 min, that is, controlling the mass ratio of waste slurry material: catalytic solution: activation solution to be 1:0.05:0.05. The reaction does not need to control a specific temperature.

[0130] (5) Stopping the introduction of all substances, and pouring out the carbonized waste slurry micro powder, to obtain a high-activity carbon sequestration mineral admixture.

[0131] The obtained high-activity carbon sequestration mineral admixture has a scanning electron microscope image shown in FIG. 1.

[0132] Example 2

[0133] A method for preparing a high-activity carbon sequestration mineral admixture using flue gas rapid carbonization, comprising the following steps:

[0134] (1) Selecting the waste slurry of concrete mixing station, precipitating and drying to obtain waste slurry material;

[0135] (2) Using an industrial pure grade magnesium chloride reagent to prepare a 0.5 mol / L magnesium chloride solution. Using an industrial pure grade caustic soda, dissolving in water, and using a flue gas transfer unit to introduce flue gas containing carbon dioxide to prepare a 1 mol / L sodium bicarbonate solution.

[0136] (3) Pouring 5 kg of waste slurry material into a 15L horizontal stirrer, and rotating and stirring at a speed of 25 rpm.

[0137] (4) Using an ultrasonic device to process the magnesium chloride solution into microdroplets (with an average droplet diameter of about 10 μm), and introducing into the stirrer loaded with the waste slurry material, controlling the total amount introduced to be 0.4 kg, that is, controlling the mass ratio of waste slurry material and magnesium chloride activation solution to be 1:0.08. At the same time, controlling the total introduction time to be 10 min, and stopping the introduction of magnesium chloride microdroplets.

[0138] (5) Using an ultrasonic device to process the sodium bicarbonate solution into microdroplets, and into the stirrer loaded with waste slurry material, while passing in the flue gas containing carbon dioxide, controlling the exhaust gas flow rate to be 3 L / min. Control the total amount of sodium bicarbonate catalytic solution to be 1 kg, control the stirrer temperature to be 60-80℃, time-consuming 30 min, after the reaction is completed, high-activity carbon sequestration mineral admixture is obtained.

[0139] The overall reaction chemical equation is as follows:

[0140] Mg 2+ +OH - →Mg(OH)2

[0141] Ca 2+ +2H + +CO3 2- +Mg(OH)2→CaCO3(aragonite)+2H2O+Mg 2+

[0142] 2Ca 2+ +2HCO3 - +Mg(OH)2→2CaCO3(aragonite)+2H2O+Mg 2+

[0143] The scanning electron microscope image of the obtained high-activity carbon sequestration mineral admixture is shown in Figure 3.

[0144] Example 3

[0145] A method for preparing high-activity carbon sequestration mineral admixture using flue gas rapid carbonization, comprising the following steps:

[0146] (1) Selecting waste slurry of concrete mixing station, precipitating and drying to obtain waste slurry material;

[0147] (2) Using industrial pure magnesium chloride reagent to prepare 0.5 mol / L magnesium chloride solution. Using industrial pure caustic soda, dissolving in water, and using flue gas transfer unit to pass in flue gas containing carbon dioxide, preparing 1 mol / L sodium bicarbonate solution.

[0148] (3) Pouring 5 kg of waste slurry material into a 15 L horizontal stirrer and rotating at a speed of 25 rpm.

[0149] (4) Using an ultrasonic device to process the magnesium chloride solution into microdroplets, and into the stirrer loaded with waste slurry material, controlling the total amount to be 0.4 kg, i.e. controlling the mass ratio of waste slurry material micro powder and magnesium chloride activation solution to be 1:0.08. At the same time, control the total time to be 10 min, stop passing in magnesium chloride microdroplets.

[0150] (5) using an ultrasonic device to treat the sodium bicarbonate solution into microdroplets (average droplet diameter of about 10 μm), and into the stirrer loaded with waste slurry material, while, into the flue gas containing carbon dioxide, flue gas into the speed of 5 L / min. Control the total amount of sodium bicarbonate catalytic solution into 1 kg, time-consuming 30 min, after the reaction to obtain high activity of carbon mineral admixture.

[0151] The scanning electron microscope of the obtained high activity of carbon mineral admixture is shown in Figure 4.

[0152] Example 4

[0153] A method for preparing high activity of carbon mineral admixture using flue gas rapid carbonization, comprising the following steps:

[0154] (1) selecting waste slurry of concrete mixing station, sedimentation and drying to obtain waste slurry material;

[0155] (2) using industrial alcohol to prepare ethanol solution with mass fraction of 50% (molar concentration of about 10 mol / L); preparing ammonium bicarbonate solution with concentration of 2 mol / L;

[0156] (3) pouring 2 kg of waste slurry material into a 5 L ball mill, using the ball mill as the reaction container, and ball milling at a speed of 15 rpm.

[0157] (4) using a steam generator to treat the ethanol solution and the ammonium bicarbonate solution into microdroplets (average droplet diameter of about 10 μm), synchronously into the reaction container loaded with waste slurry material, controlling the input speed to be 5 g / min, while into the waste gas containing carbon dioxide, the waste gas into the speed of 3 L / min, controlling the mass ratio of waste slurry material micro powder and two kinds of microdroplets to be 1:0.05:0.05. After 20 min of reaction, high activity of carbon mineral admixture is obtained.

[0158] The transmission electron microscope of the obtained high activity of carbon mineral admixture is shown in Figure 5.

[0159] Comparative Example 1

[0160] A method for carbonizing waste slurry, comprising the following steps:

[0161] (1) selecting waste slurry of concrete mixing station, sedimentation and drying to obtain waste slurry material;

[0162] (2) evenly dispersing 10 kg of waste slurry material on a storage tray, placing the storage tray in a carbonization box, controlling the carbonization condition parameters inside the box to be: relative humidity 60%, carbon dioxide concentration 20%, temperature 20℃; at the same time, controlling the carbonization time to be 24 h.

[0163] (3) After reaching the carbonation time, the carbonated waste slurry material is taken out.

[0164] Comparative Example 2

[0165] A method of carbonating waste slurry includes the following steps:

[0166] (1) Selecting waste slurry of a concrete mixing station, precipitating and drying to obtain a waste slurry material;

[0167] (2) Adding 10 kg of waste slurry material to 50 kg of water, using a stirrer to stir the mixed solution and keeping the stirring speed at 25 rpm, and passing in carbon dioxide at a speed of 5 L / min, and controlling the carbonation time to be 6 h.

[0168] (3) After reaching the carbonation time, performing solid-liquid separation and drying to obtain carbonated waste slurry powder.

[0169] The scanning electron microscope image of the obtained high-activity carbon sequestration mineral admixture is shown in FIG. 6.

[0170] Test and result analysis

[0171] The carbonation degree, calcium carbonate content and proportion, amorphous gel content, and carbon sequestration amount of the carbonation products obtained in each example and comparative example were tested and analyzed as follows. The carbonation degree was calculated based on the thermogravimetric analysis results, and the calculation method was that the mass percentage of calcium oxide existing in the form of calcium carbonate after carbonation accounted for the original calcium oxide. The aragonite, vaterite, and calcite content was obtained by quantitative X-ray diffraction analysis, and the amorphous calcium carbonate content was calculated by the difference between the quantitative X-ray diffraction and thermogravimetric analysis. The amorphous gel content was calculated by X-ray fluorescence test combined with solid-state nuclear magnetic resonance technology. The carbon sequestration amount was obtained based on the thermogravimetric analysis, which was equal to the amount of escaped carbon dioxide in the thermogravimetric analysis heating process.

[0172] The test results are shown in Table 1 below, and the percentage in Table 1 is the percentage of aragonite, vaterite, calcite, or amorphous calcium carbonate in the total weight of calcium carbonate in the product. In all carbonation products, the activity of various forms is: amorphous gel > amorphous calcium carbonate > vaterite > aragonite > magnesium-containing calcite > calcite, and the higher the content of active ingredients, the higher the overall reaction activity of the carbon sequestration mineral admixture.

[0173] Table 1

[0174] From the comparison between Example 1 and Example 2, the influence of catalyst and activator species on product composition can be obtained. Example 1 uses alcohol and ammonium salt, and obtains products rich in vaterite and amorphous calcium carbonate, and amorphous gel. Example 2 uses magnesium ions and obtains products rich in aragonite at a specific temperature. The product of Example 1 has high activity and can more fully participate in cement hydration, improve the performance of cementitious materials, and reduce the carbon footprint. The product of Example 1 has a fine and fibrous microstructure, which can be used as microfibers in cement concrete materials to improve the tensile and crack resistance of the materials.

[0175] From the comparison between Example 1 and Example 3, the influence of temperature control on product composition can be obtained. Example 1 uses alcohol and ammonium salt, and obtains products rich in vaterite and amorphous calcium carbonate, and amorphous gel. Example 3 uses magnesium ions, but without high-temperature auxiliary control of crystal form, obtains calcite, part of amorphous calcium carbonate, and magnesium-containing calcite, and does not obtain aragonite, so the activity is slightly weaker than that of the product of Example 1.

[0176] From the comparison between Example 1 and Example 4, the influence of catalyst concentration and different mechanical forces participating in the reaction on product composition can be obtained. Example 1 uses alcohol and ammonium salt, and obtains products rich in vaterite and amorphous calcium carbonate, and amorphous gel. In Example 4, the concentration of bicarbonate ions is further increased, and a higher carbonation degree is obtained within only half the time range of Example 1; and with twice the concentration of ammonium salt and mechanical grinding force participating in the reaction, the content of amorphous calcium carbonate is greatly increased, so the product has very high reactivity.

[0177] From the comparison results of all Examples 1-4 and Comparative Example 1, it can be seen that the dry carbonation in the traditional technology needs to control temperature, humidity, and carbon dioxide concentration, greatly increasing the operation difficulty and cost. In addition, after 24 hours of carbonation reaction, the carbonation degree and carbon sequestration amount are still lower than those of Examples 1-4 of the present application, and the efficiency is lower. At the same time, the main product of Comparative Example 1 is calcite, which has low activity and limited effect in the cementitious material system.

[0178] From the comparison results of all Examples 1-4 and Comparative Example 2, it can be seen that the wet carbonation technology is superior to the dry carbonation in terms of carbonation degree and carbon sequestration amount. However, Examples 1-4 of the present application obtain a higher or at least comparable carbonation degree and carbon sequestration amount than Comparative Example 2.

[0179] In addition, in terms of technical operation, the wet carbonization of Comparative Example 2 requires additional solid-liquid separation and product drying, and produces waste water, which greatly increases the difficulty of post-treatment; in terms of product activity, the main product of the wet carbonization of Comparative Example 2 is calcite, which has poor activity and functionality. In summary, the product obtained by Examples 1-4 of the present application not only has high carbonization degree and carbon sequestration amount, but also has high activity and desired functionality, and the method used is simple and does not require complex post-treatment, which is obviously superior to the traditional wet carbonization technology.

[0180] Although the present application has been described with reference to specific embodiments thereof, it should be understood by those skilled in the art that various changes can be made and equivalents can be substituted without departing from the true spirit and scope of the application. In addition, many modifications can be made to adapt a particular situation, material, composition of matter, method, method step to the spirit and scope of the present application.

Claims

1. A method for preparing a carbon sequestration mineral admixture, comprising the following steps: providing a pulverized solid waste; providing an activating liquid and a catalyzing liquid, one or both of which is optionally in the form of microdroplets; contacting and reacting the activating liquid, the catalyzing liquid, flue gas containing carbon dioxide, and the pulverized solid waste to obtain the carbon sequestration mineral admixture, the contacting being optionally performed under the action of an external mechanical force; wherein the activating liquid comprises one or more of a magnesium salt, an ammonium salt, an organic amine, and a lower alkanol as an activating agent; and the catalyzing liquid comprises carbonate ions and / or bicarbonate ions as a catalyst. 2.The method according to claim 1, wherein the solid waste contains at least 10% by weight of active substances in terms of calcium oxide. 3.The method according to claim 1 or 2, wherein the activating liquid contains an activating agent at a concentration of 0.01-10 mol / L, preferably at a concentration of 0.05-5 mol / L, 0.1-1 mol / L, or 0.2-0.5 mol / L. 4.The method according to any one of claims 1 to 3, wherein the catalyzing liquid contains a catalyst at a concentration of 0.01-10 mol / L, preferably at a concentration of 0.01-5 mol / L, 0.1-1 mol / L, or 0.1-0.5 mol / L. 5.The method according to any one of claims 1 to 4, wherein the catalyst is a carbonate or bicarbonate; or the catalyst is obtained by the reaction of an alkali metal hydroxide, aqueous ammonia, or an organic amine with carbon dioxide. 6.The method according to any one of claims 1 to 5, wherein the microdroplets have a droplet diameter of 100 nm-3000 μm. 7.The method according to any one of claims 1 to 6, wherein the weight ratio of the pulverized solid waste to the activating liquid is 1:(0.001-1); and / or the weight ratio of the pulverized solid waste to the catalyzing liquid is 1:(0.001-1). 8.The method according to any one of claims 1 to 7, wherein in the step of contacting the activating liquid, the catalyzing liquid, flue gas containing carbon dioxide, and the pulverized solid waste, an activating and catalyzing liquid containing an activating agent and a catalyst is first obtained, and then contacted with the flue gas containing carbon dioxide and the pulverized solid waste; or the activating liquid is first mixed with the pulverized solid waste, and then the catalyzing liquid and the flue gas containing carbon dioxide are contacted with the obtained mixture. 9.The method according to any one of claims 1 to 8, wherein the flue gas containing carbon dioxide has a carbon dioxide volume concentration ranging from 5% to 100%; and / or for each kilogram of the pulverized solid waste, the feeding speed of the flue gas is controlled to be 0.1-100 L / min. 10.The method according to any one of claims 1 to 9, wherein the external mechanical force is from one or more of a ball milling device, a stirring device, and a micro-vibration device.

11. The method according to any one of claims 1 to 9, wherein the activating liquid comprises a magnesium salt, and the activating liquid, the catalyzing liquid, the flue gas containing carbon dioxide and the pulverized solid waste are contacted and reacted at a temperature of 20-100°C, preferably at a temperature of normal temperature to 80°C.

12. The method according to any one of claims 1 to 9, wherein the activating liquid comprises one or more of a lower alkanol, an organic amine, an ammonium salt, or the activating liquid comprises a lower alkanol and the catalyzing liquid is obtained by reaction of ammonia water or an organic amine with carbon dioxide.

13. An apparatus for preparing a carbon-mineral admixture, the apparatus comprising a flue gas providing unit, an activating liquid and catalyzing liquid storage and processing unit, and a carbonation reaction unit.

14. The apparatus according to claim 13, wherein the flue gas providing unit provides the flue gas in the form of a compressed liquid.

15. The apparatus according to claim 13, wherein the activating liquid and catalyzing liquid storage and processing unit provides microdroplets of one or both of the activating liquid and the catalyzing liquid.

16. A carbon-mineral admixture obtained according to the method of any one of claims 1 to 12, or prepared by the apparatus of any one of claims 13 to 15.

17. The carbon-mineral admixture according to claim 16, wherein at least 60% by weight of calcium (by weight of calcium oxide) is present in the form of calcium carbonate.

18. The carbon-mineral admixture according to claim 16 or 17, wherein the calcium carbonate is present in one or more of the forms of calcite, magnesio-calcite, aragonite, vaterite, other partially crystalline calcium carbonate, amorphous calcium carbonate.

19. The carbon-mineral admixture according to any one of claims 16 to 18, wherein the other partially crystalline calcium carbonate has a crystallinity of less than 80%.

20. The carbon-mineral admixture according to any one of claims 16 to 19, wherein the carbon-mineral admixture contains amorphous silica gel, alumina gel, or silica-alumina gel.

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