Artificial aggregate as well as preparation method and application thereof

Abstract

The invention discloses an artificial aggregate as well as a preparation method and application thereof, and relates to the technical field of building materials. The preparation method of the artificial aggregate comprises the following steps: mixing the municipal solid waste incineration bottom ash, the cement, the solid waste and the water, adding the mixture into an extrusion granulator for extrusion granulation, and curing to obtain the artificial aggregate, the ratio of the mass of the municipal solid waste incineration bottom ash to the total mass of the cement and the solid waste is (0.75-5.67): 1, and the mass ratio of the cement to the solid waste is (0.5-2): 1; the solid waste comprises at least one of blast furnace slag, fly ash, steel slag and concrete waste powder. The method provided by the invention has the advantages of simple process steps, high productivity and high production efficiency, can greatly reduce the use amount of the cementing material in the artificial aggregate, improves the use amount of the municipal solid waste incineration bottom ash, can also treat solid wastes, and greatly reduces the material cost and carbon emission.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, and in particular to an artificial aggregate and a preparation method and application thereof. Background Art

[0002] Municipal solid waste incineration bottom ash (MSWIBA) is one of the main by-products of waste incineration power plants, accounting for about 80% to 90% of the total by-products. Municipal solid waste incineration bottom ash is a waste with the potential to be used as a building material. However, the potential environmental risks and poor physical properties of municipal solid waste incineration bottom ash hinder its large-scale application. At present, although there is a technology for preparing cold-bonded aggregate using municipal solid waste incineration bottom ash using disc granulation technology, it requires pre-treatment steps such as grinding and drying of the municipal solid waste incineration bottom ash. The process is cumbersome and the production capacity is small, so it is impossible to process the municipal solid waste incineration bottom ash on a large scale and efficiently. In addition, the amount of municipal solid waste incineration bottom ash used in the aggregate prepared by the existing method is small, the amount of cement used is large, and the cost and carbon emissions are high.

[0003] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0004] Based on the above-mentioned deficiencies of the prior art, the object of the present invention is to provide an artificial aggregate and a preparation method and application thereof, aiming to solve the problems of complicated process and low production capacity of the existing method of preparing aggregate using bottom ash from municipal solid waste incineration.

[0005] The technical solution of the present invention is as follows:

[0006] A first aspect of the present invention provides a method for preparing an artificial aggregate, wherein the method for preparing the artificial aggregate comprises the following steps:

[0007] Mixing municipal solid waste incineration bottom ash, cement, solid waste and water to obtain a mixture;

[0008] adding the mixture into an extrusion granulator for extrusion granulation to obtain an artificial aggregate blank;

[0009] After curing the artificial aggregate blank, the artificial aggregate is obtained;

[0010] The ratio of the mass of the bottom ash from the incineration of urban solid waste to the total mass of the cement and the solid waste is (0.75-5.67):1, and the ratio of the mass of the cement to the solid waste is (0.5-2):1;

[0011] The solid waste includes at least one of blast furnace slag, fly ash, steel slag and concrete waste powder.

[0012] Optionally, the ratio of the mass of the bottom ash from the incineration of urban solid waste to the total mass of the cement and solid waste is (1.67-5.67):1;

[0013] The mass ratio of water to cement is (0.1-0.161):1.

[0014] Optionally, the extrusion granulator is a double-roller extrusion granulator, and the process parameters of the double-roller extrusion granulator are set as: power of 15KW, efficiency of 800Kg / h, and driving wheel granulation size of 5mm.

[0015] Optionally, the particle size of the artificial aggregate is 4.2-5 mm.

[0016] Optionally, the curing is water bath curing, the temperature of the water bath curing is 25° C., and the time of the water bath curing is 7 days.

[0017] The second aspect of the present invention provides an artificial aggregate, wherein the artificial aggregate is prepared by the method for preparing the artificial aggregate as described above.

[0018] Optionally, the single particle compressive strength of the artificial aggregate is 0.67-8.25 MPa.

[0019] The third aspect of the present invention provides an application of the artificial aggregate as described above in the field of construction.

[0020] A fourth aspect of the present invention provides a use of the artificial aggregate as described above in concrete.

[0021] Optionally, the concrete is load-bearing concrete or non-load-bearing concrete.

[0022] Beneficial effects: The method provided in the present invention can omit the step of pre-treatment of the bottom ash from the incineration of municipal solid waste, and there is no need for additional grinding and sufficient drying of the bottom ash from the incineration of municipal solid waste, and the process steps are simple. In addition, the method provided in the present invention can also greatly reduce the use of cementitious materials in artificial aggregates, increase the use of bottom ash from the incineration of municipal solid waste, reduce the use of cement to 5%, and increase the use of bottom ash from the incineration of municipal solid waste to 85%. At the same time, it can also process solid waste, greatly reducing material costs and carbon emissions. The extrusion granulation method provided in the present invention can quickly process a large amount of bottom ash from the incineration of municipal solid waste, has high production capacity, and a processing speed of about 240 times that of the disc granulation technology, which greatly improves the production efficiency of artificial aggregates. At the same time, the prepared artificial aggregate has higher compressive strength. DETAILED DESCRIPTION

[0023] The present invention provides an artificial aggregate and a preparation method and application thereof. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0025] An embodiment of the present invention provides a method for preparing an artificial aggregate, wherein the method for preparing the artificial aggregate comprises the following steps:

[0026] S1. Mixing municipal solid waste incineration bottom ash, cement, solid waste and water to obtain a mixture;

[0027] S2, adding the mixture into an extrusion granulator for extrusion granulation to obtain an artificial aggregate blank;

[0028] S3, curing the artificial aggregate blank to obtain the artificial aggregate;

[0029] The ratio of the mass of the bottom ash from the incineration of urban solid waste to the total mass of the cement and the solid waste is (0.75-5.67):1, and the ratio of the mass of the cement to the solid waste is (0.5-2):1;

[0030] The solid waste includes at least one of blast furnace slag, fly ash, steel slag and concrete waste powder.

[0031] The method provided in the embodiment of the present invention can omit the step of pre-treatment of the bottom ash from the incineration of municipal solid waste, and there is no need to perform additional grinding and sufficient drying on the bottom ash from the incineration of municipal solid waste, and the process steps are simple. In addition, the method provided in the embodiment of the present invention can also greatly reduce the use of cementitious materials in artificial aggregates, increase the use of bottom ash from the incineration of municipal solid waste, reduce the use of cement to 5%, and increase the use of bottom ash from the incineration of municipal solid waste to 85% (the mass proportion of the bottom ash from the incineration of municipal solid waste in the powder material is 85%, and the mass proportion of cement in the powder material is 5%; wherein, the powder material refers to the material other than water used in the preparation process of artificial aggregates, and in this embodiment, the powder material is composed of bottom ash from the incineration of municipal solid waste, cement and solid waste. However, the preparation of artificial aggregates cannot be achieved by using the disc granulation method with 5% cement and 85% bottom ash from the incineration of municipal solid waste), and solid waste can also be processed at the same time, greatly reducing material costs and carbon emissions. The extrusion granulation method provided by the present invention can quickly process a large amount of municipal solid waste incineration bottom ash, has high production capacity, and a processing speed of about 240 times that of the disc granulation technology, which greatly improves the production efficiency of artificial aggregates. At the same time, the prepared artificial aggregates have higher compressive strength.

[0032] In step S1, the mass ratio of the cement to the solid waste is (0.5-2):1, for example, it can be 0.5:1, 0.8:1, 1:1, 1.2:1, 1.5:1, 1.8:1 or 2:1, etc.

[0033] In some embodiments, the ratio of the mass of the municipal solid waste incineration bottom ash to the total mass of the cement and solid waste is (1.67-5.67):1, for example, it can be 1.67:1, 1.7:1, 1.8:1, 1.9:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1 or 5.67:1, etc. In other words, the ratio of the total mass of the cement and solid waste to the mass of the municipal solid waste incineration bottom ash is 1:(1.67-5.67).

[0034] In some specific embodiments, the ratio of the mass of the urban solid waste incineration bottom ash to the total mass of the cement and solid waste is (2.33-5.67):1, that is, the mass of the urban solid waste incineration bottom ash accounts for 70%-85% of the total mass of the urban solid waste incineration bottom ash, cement and solid waste.

[0035] In some embodiments, the mass ratio of water to cement is (0.1-0.161):1, for example, it can be 0.1:1, 0.11:1, 0.12:1, 0.13:1, 0.14:1, 0.15:1, 0.16:1 or 0.161:1, etc.

[0036] In step S2, in some embodiments, extrusion granulation is performed in an open die, which relies on the friction between the material and the die wall to squeeze the material to form a dense stack, and then extrude it from the opening of the die, and a cutting device is installed on the outside of the die opening to cut the extruded material column into columnar particles. The present invention cleverly applies the extrusion granulation method to the preparation of waste incineration bottom ash artificial aggregate. Extrusion granulation facilitates the molding of artificial aggregate, can increase the use of municipal solid waste incineration bottom ash in artificial aggregate, and reduce the use of cementitious materials.

[0037] In some embodiments, the extrusion granulator is a double-roller extrusion granulator, and the process parameters of the double-roller extrusion granulator are set as follows: power is 15KW, efficiency is 800Kg / h, and the driving wheel granulation size is 5mm.

[0038] In step S3, in some embodiments, the curing is water bath curing, the water bath curing temperature is 25° C., and the water bath curing time is 7 days. The strength of the artificial aggregate is further improved by water bath curing.

[0039] In some embodiments, the particle size of the artificial aggregate is 4.2-5 mm.

[0040] An embodiment of the present invention further provides an artificial aggregate, wherein the artificial aggregate is prepared by the method for preparing the artificial aggregate as described above.

[0041] In some embodiments, the single particle compressive strength of the artificial aggregate is 0.67-8.25 MPa.

[0042] The embodiment of the present invention further provides a use of the artificial aggregate as described above in the field of construction.

[0043] The embodiment of the present invention further provides a use of the artificial aggregate as described above in concrete.

[0044] In some embodiments, the concrete is load-bearing concrete or non-load-bearing concrete, and can be specifically applied to roadbed stabilized soil or non-structural shoulders.

[0045] The present invention will be further described below by means of specific examples.

[0046] The cement used in the following examples is ordinary Portland cement.

[0047] Table 1. Proportion of artificial aggregate in the following examples (mass ratio)

[0048]

[0049]

[0050] Note: The bottom ash here refers to the bottom ash from the incineration of municipal solid waste;

[0051] Bottom ash / (cement + blast furnace slag) is the ratio of the mass of bottom ash from municipal solid waste incineration to the sum of the mass of cement and blast furnace slag;

[0052] Water-cement ratio is the mass ratio of water to cement;

[0053] Cement / blast furnace slag is the mass ratio of cement to blast furnace slag.

[0054] Example 1

[0055] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0056] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 1 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0057] The mixture was placed in a roller extrusion granulator (purchased from Changzhou Zhongte Automation Equipment Co., Ltd., model ZT roller extrusion granulator, size 1200×630×1300mm), the power was set to 15KW, the efficiency was 800kg / h, the driving wheel granulation size was 5mm, extrusion granulation was performed, and after passing through a 2.75mm sieve, an artificial aggregate blank was obtained;

[0058] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0059] Example 2

[0060] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0061] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 2 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0062] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0063] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0064] Example 3

[0065] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0066] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 3 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0067] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0068] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0069] Example 4

[0070] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0071] Mix the bottom ash from municipal solid waste incineration, cement, blast furnace slag and water according to the proportions of Example 4 in Table 1, and make the total mass of the bottom ash from municipal solid waste incineration, cement and blast furnace slag be 1000 g to obtain a mixture;

[0072] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0073] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0074] Example 5

[0075] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0076] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 5 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0077] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0078] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0079] Example 6

[0080] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0081] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 6 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0082] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0083] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0084] Example 7

[0085] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0086] Mix the bottom ash from municipal solid waste incineration, cement, blast furnace slag and water according to the proportions of Example 7 in Table 1, and make the total mass of the bottom ash from municipal solid waste incineration, cement and blast furnace slag be 1000 g to obtain a mixture;

[0087] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0088] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0089] Example 8

[0090] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0091] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 8 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0092] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0093] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0094] Example 9

[0095] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0096] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 9 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0097] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0098] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0099] Example 10

[0100] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0101] Mixing the bottom ash from municipal solid waste incineration, cement, blast furnace slag and water according to the proportions of Example 10 in Table 1, and making the total mass of the bottom ash from municipal solid waste incineration, cement and blast furnace slag be 1000 g, to obtain a mixture;

[0102] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0103] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0104] Embodiment 11

[0105] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0106] Mix the bottom ash from municipal solid waste incineration, cement, blast furnace slag and water according to the proportions of Example 11 in Table 1, and make the total mass of the bottom ash from municipal solid waste incineration, cement and blast furnace slag be 1000 g to obtain a mixture;

[0107] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0108] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0109] Example 12

[0110] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0111] Mix the bottom ash from municipal solid waste incineration, cement, blast furnace slag and water according to the proportions of Example 12 in Table 1, and make the total mass of the bottom ash from municipal solid waste incineration, cement and blast furnace slag be 1000 g to obtain a mixture;

[0112] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0113] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0114] Embodiment 13

[0115] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0116] Mix the bottom ash from municipal solid waste incineration, cement, blast furnace slag and water according to the proportions of Example 13 in Table 1, and make the total mass of the bottom ash from municipal solid waste incineration, cement and blast furnace slag be 1000 g to obtain a mixture;

[0117] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0118] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0119] Embodiment 14

[0120] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0121] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 14 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0122] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0123] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0124] Embodiment 15

[0125] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0126] Mix the bottom ash from municipal solid waste incineration, cement, blast furnace slag and water according to the proportions of Example 15 in Table 1, and make the total mass of the bottom ash from municipal solid waste incineration, cement and blast furnace slag be 1000 g to obtain a mixture;

[0127] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0128] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0129] Example 16

[0130] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0131] Mix the bottom ash from municipal solid waste incineration, cement, blast furnace slag and water according to the proportions of Example 16 in Table 1, and make the total mass of the bottom ash from municipal solid waste incineration, cement and blast furnace slag be 1000 g to obtain a mixture;

[0132] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0133] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0134] Embodiment 17

[0135] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0136] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 17 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0137] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0138] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0139] Embodiment 18

[0140] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0141] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 18 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0142] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0143] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0144] Embodiment 19

[0145] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0146] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 19 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0147] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0148] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0149] Embodiment 20

[0150] This embodiment provides a method for preparing an artificial aggregate, comprising the following steps:

[0151] Mix the bottom ash from the incineration of municipal solid waste, cement, blast furnace slag and water according to the proportions of Example 20 in Table 1, and make the total mass of the bottom ash from the incineration of municipal solid waste, cement and blast furnace slag be 1000 g to obtain a mixture;

[0152] The mixture is placed in a double-roll extrusion granulator (same as in Example 1), with a power of 15 KW, an efficiency of 800 kg / h, and a driving wheel granulation size of 5 mm, and extrusion granulation is performed, and after passing through a 2.75 mm sieve, an artificial aggregate blank is obtained;

[0153] The artificial aggregate green body was cured in a water bath (temperature was 25° C.) for 7 days to obtain the artificial aggregate.

[0154] test:

[0155] The average particle size, average maximum bearing capacity and average compressive strength of the artificial aggregates prepared in Examples 1 to 20 were tested, wherein the average compressive strength was tested using a single particle compressive strength test, and the formula used was: σ = 2.8P / (πd 2 ). Where σ is the compressive strength, unit is MPa, P is the peak force, unit is N, and d is the diameter of the artificial aggregate, unit is mm. The results are shown in Table 2.

[0156] Table 2. Test results

[0157]

[0158]

[0159] It can be seen that the artificial aggregate provided by the embodiments of the present invention has sufficient compressive strength and can be used in concrete of load-bearing structures, wherein the artificial aggregate in Example 4 has the highest compressive strength of 8.20 MPa. Although the compressive strength of the artificial aggregate in Example 20 is relatively low, it can still be used in concrete of non-load-bearing structures, wherein the amount of bottom ash from municipal solid waste incineration is as high as 85% and the amount of cement is as low as 5%.

[0160] Comparative Example 1

[0161] This comparative example provides a method for preparing an artificial aggregate, which is different from Example 4 only in that the artificial aggregate is prepared by a disc granulation method.

[0162] The average compressive strength of the artificial aggregate prepared in Comparative Example 1 was tested to be 2.76 MPa. The compressive strength of the artificial aggregate in Example 4 was 8.20 MPa. It can be seen that the artificial aggregate prepared by the method provided by the present invention has a higher compressive strength than the artificial aggregate prepared by the disc granulation method. The extrusion granulation method in the present invention works synergistically with specific raw materials (bottom ash from municipal solid waste incineration, cement, solid waste), so that the artificial aggregate has a higher compressive strength.

[0163] In summary, the present invention provides an artificial aggregate and a preparation method and application thereof. The method provided in the present invention can omit the step of pre-treatment of the bottom ash from the incineration of urban solid waste, and there is no need for additional grinding and sufficient drying of the bottom ash from the incineration of urban solid waste, and the process steps are simple. In addition, the method provided by the present invention can also greatly reduce the use of cementitious materials in artificial aggregates, increase the use of bottom ash from the incineration of urban solid waste, reduce the use of cement to 5%, and increase the use of bottom ash from the incineration of urban solid waste to 85%. At the same time, solid waste can also be processed, greatly reducing material costs and carbon emissions. The extrusion granulation method provided by the present invention can quickly process a large amount of bottom ash from the incineration of urban solid waste, has high production capacity, and a processing speed of about 240 times that of the disc granulation technology, which greatly improves the production efficiency of artificial aggregates. At the same time, the prepared artificial aggregate has higher compressive strength.

[0164] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for preparing artificial aggregate, characterized in that: The method for preparing the artificial aggregate comprises the following steps: Mixing municipal solid waste incineration bottom ash, cement, solid waste and water to obtain a mixture; adding the mixture into an extrusion granulator for extrusion granulation to obtain an artificial aggregate blank; After curing the artificial aggregate blank, the artificial aggregate is obtained; The ratio of the mass of the bottom ash from the incineration of urban solid waste to the total mass of the cement and the solid waste is (0.75-5.67):1, and the ratio of the mass of the cement to the solid waste is (0.5-2):1; The solid waste includes at least one of blast furnace slag, fly ash, steel slag and concrete waste powder.

2. The method for preparing artificial aggregate according to claim 1, characterized in that: The ratio of the mass of the bottom ash from the incineration of the municipal solid waste to the total mass of the cement and the solid waste is (1.67-5.67):1; The mass ratio of water to cement is (0.1-0.161):

1.

3. The method for preparing artificial aggregate according to claim 1, characterized in that: The extrusion granulator is a double-roller extrusion granulator, and the process parameters of the double-roller extrusion granulator are set as follows: power is 15KW, efficiency is 800Kg / h, and the driving wheel granulation size is 5mm.

4. The method for preparing artificial aggregate according to claim 1, characterized in that: The particle size of the artificial aggregate is 4.2-5 mm.

5. The method for preparing artificial aggregate according to claim 1, characterized in that: The curing is water bath curing, the temperature of the water bath curing is 25° C., and the time of the water bath curing is 7 days.

6. An artificial aggregate, characterized in that: The artificial aggregate is prepared by the preparation method of any one of claims 1 to 5.

7. The artificial aggregate according to claim 6, characterized in that: The single particle compressive strength of the artificial aggregate is 0.67-8.25 MPa.

8. Use of the artificial aggregate according to any one of claims 6 to 7 in the field of construction.

9. Use of the artificial aggregate according to any one of claims 6 to 7 in concrete.

10. The use according to claim 9, characterized in that: The concrete is load-bearing concrete or non-load-bearing concrete.

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