Preparation method of high-strength ceramsite

Abstract

The invention relates to the technical field of solid waste resource utilization and high-performance ceramic preparation, in particular to a preparation method of high-strength ceramsite. According to the method, urban road sweeping garbage and fly ash are adopted as raw materials, a binder and a pore forming agent are applied for combined granulation, ceramsite blanks obtained through granulation are sintered, high-strength ceramsite is finally obtained, and the strength of the high-strength ceramsite particles obtained through the method reaches 96.74-128.73 MPa; the density grade is 500-700 grade, and the 1h water absorption rate is 6.83-16.39%. According to the method, urban road sweeping garbage and fly ash are used as raw materials, the raw materials are wide in source and large in output; on one hand, the production cost of the ceramsite is reduced, on the other hand, the current situation that the resource utilization rate of the road sweeping garbage is low can be solved, the dual purposes of protecting the environment and turning waste into wealth can be achieved, and good application prospects are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of solid waste resource utilization and high-performance ceramic preparation, and in particular to a method for preparing high-strength ceramsite. Background Art

[0002] Road sweeping garbage refers to fine particles with a particle size of less than 10mm generated when sweeping roads and streets, and its quantity and composition vary greatly. According to my country's "List of Classification and Codes of Solid Waste", road sweeping garbage belongs to other garbage from non-specific industries, mainly from garbage swept from public places in environmental sanitation management services, accounting for 10-15% of the mass of urban garbage, and should be collected and disposed of in a comprehensive system as one of the urban waste streams. As for the generation of road sweeping garbage, it also includes dust brought by the construction process and fine particles left after the storage of construction waste that are difficult to clean up, particles or part of the silt remaining on the road surface after severe weather such as strong winds and precipitation, fallen objects left during vehicle transportation that need to be cleaned up, and relatively dry surface soil blown up due to imperfect greening. Therefore, road sweeping garbage has the characteristics of small particle size, easy to float with air flow after water evaporates, extremely easy to generate, and difficult to recycle.

[0003] Fly ash is an industrial byproduct produced during the combustion of coal in thermal power plants. It is one of the most complex man-made materials. Improper disposal of fly ash has become an environmental problem and has caused waste of recyclable resources. Therefore, the resource utilization of fly ash is urgent. So far, scholars around the world have studied the resource utilization of fly ash in building materials, catalysis, deep separation, zeolite synthesis and preparation of ceramsite.

[0004] Road cleaning waste and fly ash have direct or indirect harm to the environment and human body on which we depend for survival. According to statistics, at present, most of the fly ash is utilized as a resource at home and abroad, and there is little research on road cleaning waste at home and abroad. If it is further utilized as a resource, it can not only "turn waste into treasure" to create new value, but also be beneficial to the protection of the ecological environment. Summary of the invention

[0005] The purpose of the invention is to provide a method for preparing high-strength ceramsite to solve the problem that there is no effective resource utilization method for road sweeping garbage.

[0006] To achieve the above object, the present invention adopts the following technical scheme: a method for preparing high-strength ceramsite, comprising the following steps: S1, take road sweeping garbage, fly ash, binder and foaming agent, mix the raw materials evenly and prepare ceramsite embryonic material; S2, drying, firing and cooling the ceramsite blank prepared in S1 to obtain the high-strength ceramsite of the present invention, the strength of which can reach above 120 MPa.

[0007] Furthermore, in S1, the road sweeping garbage is the garbage unloaded by the sanitation garbage sweeper; the road sweeping garbage needs to be pre-treated before use; the pre-treatment includes removing large floating objects and debris, draining water, drying, crushing, and passing through a 100-mesh sieve.

[0008] Furthermore, in the above S1, the binder includes sodium silicate, and the foaming agent includes sawdust.

[0009] Furthermore, in the S1, 70-95 parts of road sweeping garbage, 5-30 parts of fly ash, 5-30 parts of sodium silicate, and 2-8 parts of sawdust are taken.

[0010] Furthermore, in the S1, 20 to 40 parts of water are added to the uniformly mixed raw materials, mixed uniformly, and granulated.

[0011] Furthermore, the particle size of the ceramsite blank is 10±1 mm.

[0012] Furthermore, in the S2, the drying temperature is 105°C, and the dried ceramsite blank is preheated before firing.

[0013] Furthermore, the preheating treatment is performed at a temperature of 300-600°C and for a time of 10-40 minutes.

[0014] Furthermore, in the S2, the sintering temperature is 850-1150°C, and the sintering time is 10-40 minutes; after sintering, the sintering is naturally cooled to room temperature.

[0015] Furthermore, the strength of the high-strength ceramsite is 96.74~128.73Mpa.

[0016] Beneficial effects of the present invention: 1. The road sweeping garbage and fly ash high-strength ceramsite involved in the present invention has a particle strength of 96.74-128.73 MPa; a density grade of 500-700, and a 1h water absorption rate of 6.83-16.39%; 2. The main raw material used in the present invention is road sweeping garbage collected by garbage sweepers, which has a wide source and a large amount of production. The high-strength ceramsite is prepared from it, which reduces the production cost of ceramsite on the one hand, and solves the current situation of low resource utilization rate of road sweeping garbage on the other hand, and can achieve the dual purpose of environmental protection and turning waste into treasure; 3. The high-strength ceramsite obtained by the present invention can be used in the fields of building materials, refractory materials, etc., and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a bar graph of the main component contents of road sweeping garbage in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0019] Example 1 After removing debris from the road sweeping garbage, dry it at 105℃ to constant weight, crush it through a 100-mesh sieve, and seal it for later use.

[0020] The composition of the road sweeping waste after the above pretreatment was analyzed by X-ray fluorescence spectroscopy (XRF). Figure 1 shown.

[0021] Take 90 parts of the above-mentioned road sweeping garbage and 10 parts of fly ash, add 20 parts of sodium silicate and 5 parts of sawdust, mix and grind, add 30 parts of water and stir evenly, granulate, and obtain ceramsite blanks with a diameter of 10±1 mm.

[0022] The obtained ceramsite blank was dried at 105°C, preheated at 500°C for 25min, then heated to 1050°C and calcined for 20min, and then cooled to room temperature to obtain road sweeping garbage / fly ash ceramsite.

[0023] The road sweeping garbage / fly ash ceramsite obtained in this embodiment has a density grade of 600 and a bulk density of 585.66 kg / m 3 The particle strength is 110.35MPa and the water absorption rate in 1h is 15.39%.

[0024] Example 2 Take 85 parts of road sweeping garbage after pretreatment in Example 1 and 15 parts of fly ash, add 30 parts of sodium silicate and 5 parts of sawdust, mix and grind, add 30 parts of water and stir evenly, granulate, and obtain ceramsite blanks with a diameter of 10±1 mm.

[0025] The obtained ceramsite blank was dried at 105°C, preheated at 500°C for 25min, then heated to 1050°C and calcined for 20min, and then cooled to room temperature to obtain road sweeping garbage / fly ash ceramsite.

[0026] The road sweeping garbage / fly ash ceramsite obtained in this embodiment has a density grade of 600 and a bulk density of 551.14 kg / m 3 The particle strength is 127MPa and the water absorption rate in 1h is 6.83%.

[0027] Example 3 Take 85 parts of road sweeping garbage after pretreatment in Example 1 and 15 parts of fly ash, add 20 parts of sodium silicate and 5 parts of sawdust, mix and grind, add 30 parts of water and stir evenly, granulate, and obtain ceramsite blanks with a diameter of 10±1 mm.

[0028] The obtained ceramsite blank was dried at 105°C, preheated at 600°C for 25min, then heated to 1050°C and calcined for 20min, and then cooled to room temperature to obtain road sweeping garbage / fly ash ceramsite.

[0029] The road sweeping garbage / fly ash ceramsite obtained in this embodiment has a density grade of 600 and a bulk density of 518.56 kg / m 3 The particle strength is 126.63MPa and the water absorption rate in 1h is 16.39%.

[0030] Example 4 Take 85 parts of road sweeping garbage after pretreatment in Example 1 and 15 parts of fly ash, add 20 parts of sodium silicate and 5 parts of sawdust, mix and grind, add 30 parts of water and stir evenly, granulate, and obtain ceramsite blanks with a diameter of 10±1 mm.

[0031] The obtained ceramsite blank was dried at 105°C, preheated at 450°C for 35min, then heated to 1050°C and calcined for 20min, and then cooled to room temperature to obtain road sweeping garbage / fly ash ceramsite.

[0032] The road sweeping garbage / fly ash ceramsite obtained in this embodiment has a density grade of 600 and a bulk density of 558.31 kg / m 3 The particle strength is 112.33MPa and the water absorption rate in 1h is 15.24%.

[0033] Example 5 Take 85 parts of road sweeping garbage after pretreatment in Example 1 and 15 parts of fly ash, add 20 parts of sodium silicate and 5 parts of sawdust, mix and grind, add 30 parts of water and stir evenly, granulate, and obtain ceramsite blanks with a diameter of 10±1 mm.

[0034] The obtained ceramsite blank was dried at 105°C, preheated at 450°C for 20 min, then heated to 1075°C and calcined for 20 min, and then cooled to room temperature to obtain road sweeping garbage / fly ash ceramsite.

[0035] The road sweeping garbage / fly ash ceramsite obtained in this example has a density grade of 500 and a bulk density of 429.53 kg / m 3 The particle strength is 128.73MPa and the water absorption rate in 1h is 12.26%.

[0036] Example 6 Take 85 parts of road sweeping garbage after pretreatment in Example 1 and 15 parts of fly ash, add 15 parts of sodium silicate and 5 parts of sawdust, mix and grind, add 30 parts of water and stir evenly, granulate, and obtain ceramsite blanks with a diameter of 10±1 mm.

[0037] The obtained ceramsite blank was dried at 105°C, preheated at 450°C for 20 min, then heated to 1050°C and calcined for 30 min, and then cooled to room temperature to obtain road sweeping garbage / fly ash ceramsite.

[0038] The road sweeping garbage / fly ash ceramsite obtained in this example has a density grade of 600 and a bulk density of 503.76 kg / m 3 The particle strength is 96.74MPa and the water absorption rate in 1h is 14.02%.

[0039] Comparative Example 1 In this comparative example, the road sweeping waste in Example 1 was replaced with construction waste, and the compressive strength of the ceramsite finally obtained was 9.26 MPa.

[0040] It can be seen that high-strength ceramsite can be prepared by the method of the present invention. In Example 5, the maximum strength of the ceramsite reaches 128.73 MPa. The strength of the ceramsite is much greater than that of the ceramsite obtained using construction waste as raw material in Comparative Example 1. It has good application prospects in the fields of building materials, refractory materials, etc.

[0041] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, all technical solutions that are the same or similar to those of the present application fall within the protection scope of the present invention.

Claims

1. A method for preparing high-strength ceramsite, characterized in that: The following steps are involved: S1, take road sweeping garbage, fly ash, binder and foaming agent, mix the raw materials evenly and prepare ceramsite embryonic material; S2, drying, firing and cooling the ceramsite blank prepared in S1 to obtain the high-strength ceramsite of the present invention, the strength of which can reach above 120 MPa.

2. The method for preparing high-strength ceramsite according to claim 1, wherein: In S1, the road sweeping garbage is the garbage unloaded by the sanitation garbage sweeper; the road sweeping garbage needs to be pre-treated before use; the pre-treatment includes removing large floating objects and debris, draining water, drying, crushing, and passing through a 100-mesh sieve.

3. The method for preparing high-strength ceramsite according to claim 1, characterized in that: In the above-mentioned S1, the binder includes sodium silicate, and the foaming agent includes sawdust.

4. The method for preparing high-strength ceramsite according to claim 3, characterized in that: In the S1, 70-95 parts of road sweeping garbage, 5-30 parts of fly ash, 5-30 parts of sodium silicate and 2-8 parts of sawdust are taken.

5. A method for preparing high-strength ceramsite according to claim 4, characterized in that: In the above-mentioned S1, 20 to 40 parts of water are added to the uniformly mixed raw materials, mixed uniformly, and granulated.

6. The method for preparing high-strength ceramsite according to claim 1, characterized in that: The particle size of the ceramsite blank is 10±1 mm.

7. The method for preparing high-strength ceramsite according to claim 1, characterized in that: In the above-mentioned S2, the drying temperature is 105° C., and the dried ceramsite blank is preheated before firing.

8. The method for preparing high-strength ceramsite according to claim 7, characterized in that: The preheating treatment is performed at a temperature of 300 to 600° C. and for a time of 10 to 40 minutes.

9. The method for preparing high-strength ceramsite according to claim 1, characterized in that: In the above-mentioned S2, the sintering temperature is 850-1150° C., and the sintering time is 10-40 min; after sintering, the sintered product is naturally cooled to room temperature.

10. A method for preparing high-strength ceramsite according to any one of claims 1 to 9, characterized in that: The strength of the high-strength ceramsite is 96.74-128.73Mpa.

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