CN115849950A - Lightweight aggregate, preparation process and application thereof - Google Patents

Abstract

The invention belongs to the field of building materials, and particularly relates to a lightweight aggregate, a preparation process and application thereof. The lightweight aggregate comprises the following raw material components: straw carbon fiber, industrial sludge, inorganic materials, organic gel materials and organic silicon; the weight of the organogel material is 5-8% of the weight of the industrial sludge; the weight of the organic silicon is 1-2% of that of the industrial sludge; the mass ratio of the straw fiber to the industrial sludge to the inorganic material is 20-25. The lightweight aggregate of the invention takes agricultural wastes and industrial wastes as main raw materials, and the lightweight aggregate obtained by optimizing the component proportion and designing the preparation process has small bulk density, high strength, good waterproofness, stability and safety, and can be used as the raw material of lightweight aggregate concrete and used for non-bearing walls, external walls and large-span walls of high-rise buildings.

Description

A kind of lightweight aggregate, its preparation process and its application

technical field

The invention belongs to the field of building materials, and in particular relates to a lightweight aggregate, a preparation process and an application thereof.

Background technique

Aggregate is a granular loose material that acts as a skeleton or filling in concrete. It is mainly used in cement concrete, asphalt concrete, road foundation, mortar and other fields. It is a very important raw material in construction. As a new type of aggregate, lightweight aggregate is becoming more and more popular. At the same time, due to its low density, good thermal insulation, and good earthquake resistance, it can be used in high-rise and long-span buildings, and the wider the range of materials used.

There are many types of lightweight aggregates, including natural lightweight aggregates (pumice, volcanic slag, etc.), industrial waste (fly ash ceramsite, expanded slag beads, etc.) and artificial lightweight aggregates (shale ceramsite, clay ceramsite, etc.) , expanded perlite, etc.). With the consumption of natural lightweight aggregates, artificial lightweight aggregates prepared from waste materials are gradually increasing. At the same time, due to the improvement of people's living standards, the requirements for living environment are also getting higher and higher. Using a single type of lightweight aggregate or The safety requirements of directly using waste to prepare aggregates can no longer meet the needs of today's society.

CN108585568B discloses a method for preparing high-quality lightweight aggregates from sludge. Mix sludge, plant fibers, quicklime and water glass evenly, heat them with microwaves to make balls, and then spray water-repellent on the sludge balls and cover them with coating materials. Sludge balls are coated and dried. Although this prior art makes full use of sludge and straw waste, due to the complex composition of sludge, it not only contains a large amount of heavy metals, but also contains a large amount of organic matter. Similarly, straw also contains a large amount of organic matter. If it is not dried in time after absorbing water, it will easily rot and deteriorate. Odor is emitted, and the subsequent stability of the lightweight aggregate is easily deteriorated. CN111943542B discloses a method for preparing aluminum-titanium slag lightweight aggregate by using biological materials. The aluminum-titanium slag, high-activity calcium oxide, high-alumina bauxite clinker, and bio-organic pore-forming agent are respectively crushed to below 100 meshes to obtain Aluminum-titanium slag powder, high-activity calcium oxide powder, high-alumina bauxite clinker powder, and bio-organic pore-forming agent powder are mixed in proportion and finely ground, then put into a pelletizer, add water to obtain aluminum-titanium slag pellets, and place Curing at room temperature for 12-24 hours, and then drum drying to obtain titanium-aluminum slag pellets and sintering at high temperature in a rotary kiln to obtain aluminum-titanium slag lightweight aggregate. Although this prior art utilizes some bio-organic matter, its content is small, and it is still dominated by industrial materials, and its density is still 1.45g/cm ³ , which cannot meet the requirements of lightweight aggregate.

In view of this, how to obtain new lightweight aggregates with light weight, high strength and safety by using waste is a problem that needs to be solved at present.

Contents of the invention

Aiming at the deficiencies of the prior art, the object of the present invention is to provide a lightweight aggregate, a preparation process and its application. The lightweight aggregate uses agricultural waste and industrial waste as the main raw materials. By optimizing the distribution ratio of the components, the design The preparation process, the obtained lightweight aggregate has low bulk density, high strength, good water resistance, stability, and safety, and can be used as a raw material for lightweight aggregate concrete for non-load-bearing walls, exterior walls, and long-span buildings of high-rise buildings. walls etc.

In order to achieve the above object, the present invention provides a lightweight aggregate, which includes the following raw material components: straw charcoal fiber, industrial sludge, inorganic material, organic gel material, organic silicon;

The weight of the organogel material is 5-8% of the weight of the industrial sludge;

The weight of the organosilicon is 1-2% of the weight of the industrial sludge;

The mass ratio of the straw fiber, industrial sludge and inorganic material is 20-25:60-70:5-10.

In this technical solution, straw charcoal fiber and industrial sludge are used as main raw materials, and straw charcoal fiber has an irregular skeleton structure and light weight characteristics, and is combined with industrial sludge, and at the same time, holes are further made by organic gel materials, inorganic materials Increase the strength, and finally absorb a layer of organic silicon on the inside and outside surface of the obtained lightweight bone particles, and the obtained lightweight bone particles have the characteristics of high packing density, high strength, good stability and water resistance.

Further, in the above technical solution, the straw charcoal fiber is obtained by drying straw, crushing, drying, dry distillation, and cooling in a charcoal making equipment, and the particle diameter of the straw charcoal fiber is 100-120 mesh. Specifically, the straw carbonization process can be a conventional process. In the present invention, the carbonized straw fiber is used as a lightweight material for lightweight aggregate. After carbonization, the protein and other substances in the straw are destroyed, the pores are further released, the hardness is strengthened, the weight is light, and the subsequent water absorption will not deteriorate, and it is realized. Resource utilization of straw.

Further, in the above technical solution, the industrial sludge is sludge after heavy removal treatment in a large industrial sewage station, and its moisture content is 70-75%. Industrial sludge is currently a major problem in solid waste treatment. After removing heavy metals, the sludge is safe and mainly contains silica, aluminum oxide, ferric oxide, calcium oxide, magnesium oxide, titanium oxide, Potassium oxide, sodium oxide, manganese dioxide and other components, used in building materials, can greatly alleviate the problem of sludge solid waste treatment and realize resource utilization.

Further, in the above technical solution, the inorganic cementitious material is a mixture of Portland cement and alumina in any proportion.

Further, in the above technical solution, the organic gelling material is one or more of polyvinyl alcohol, polyacrylamide, and polyurethane.

The present invention also provides a preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the ratio, granulate, and dry quickly to obtain the sludge fiber granules with pores;

S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 1-3 hours, use a disc to granulate, and finally wrap the inorganic material on the outermost layer for curing 1-3h, get the aggregate pellets;

S3. Put the aggregate particles obtained in S2 into a rotary kiln for drying and calcining. After cooling, mix them with organic silicon, and place them in a closed negative pressure state for 0.5-1h to obtain lightweight aggregates.

In the present invention, the straw carbon fiber is first mixed with a certain amount of industrial sludge and granulated to obtain sludge fiber particles with fibers as the skeleton, in which some carbon fiber pores are filled with sludge, and because the sludge contains a large amount of water, After high-temperature rapid drying, the internal water vapor quickly rushes out to form pores, further increasing the pores of sludge fiber particles, and at the same time, the partial filling of sludge can increase the strength of straw carbon fibers and increase the stability of aggregates; After mud and organic gel are mixed, sludge fiber particles are added, and a layer of sludge organic gel mixture can be wrapped on the surface of sludge fiber particles. In the process of disc granulation, inorganic materials are coated on the outermost layer. In the process of drying and calcining in the rotary kiln, due to the low boiling point of the organic gel material, it volatilizes after high temperature, leaving a large number of holes in the sludge layer, and due to the existence of the outer layer of inorganic materials, its strength is not affected.

Further, in the above technical solution, in S1, the granulated particle size is 0.5-2mm, and the drying temperature is 100-120°C; in S2, the granulated particle size is 2-6mm.

Further, in the above technical scheme, in S3, the temperature of the rotary kiln is raised in two stages, the first stage starts from room temperature to 100°C, the temperature rises for 20-30min, and the rotation speed is 1-2r/min; the second stage heats up from 100°C to 1050°C, the heating time is 30-40min, and the speed is controlled at 3-4r/min. In this technical solution, by heating up in stages, the first stage of low-temperature drying can pre-solidify the sludge and inorganic materials in the aggregate granules, and the second stage of high-temperature calcination can burn off the organic gel material, and the sludge in the aggregate granules A large number of holes are formed in the layer, and at the same time, the overall strength of the aggregate particles is improved through high-temperature calcination, and the obtained lightweight aggregate has low density and high strength.

Further, in the above technical solution, in S3, the pressure in the airtight negative pressure state is negative 200-500kPa. In this technical solution, a small amount of organic silicon is added in a closed negative pressure state, and the organic silicon is infiltrated into the interior and surface of the lightweight aggregate through the effect of negative pressure, thereby increasing the hydrophobicity.

The present invention also provides an application of the above-mentioned lightweight aggregate in high-rise buildings, exterior walls and long-span walls.

The beneficial effects that the present invention has are:

The invention uses straw charcoal fiber and industrial sludge as main raw materials, utilizes straw charcoal fiber with irregular skeleton structure and light weight characteristics, cooperates with industrial sludge, optimizes component distribution ratio and preparation process design, and obtains light weight Bone pellets have the characteristics of low bulk density, high strength, good stability and water resistance, and high safety; while realizing the resource utilization of waste, they can reduce the consumption of natural aggregates and have broad market application prospects.

The preparation process of the present invention firstly mixes straw charcoal fiber with part of sludge, granulates, and quickly dries at high temperature to obtain sludge fiber granules with high porosity and high strength, and then adds them to the sludge mixed with organic gel material The surface is coated with a layer of high-strength inorganic material. After high-temperature calcination, the organic gel material and water volatilize to form pores, and form a pore structure in the sludge layer, which can further increase the strength of the material. Finally Adsorb a layer of organic silicon on the inside and outside surface of the obtained lightweight bone particles to improve the waterproof, temperature resistance and weather resistance of the material. The obtained material can be used as a raw material for lightweight aggregate concrete, and can be used for non-load-bearing walls of high-rise buildings, External walls, large-span walls and other fields.

Detailed ways

The experimental methods in the following examples are conventional methods unless otherwise specified. Unless otherwise specified, the raw materials involved in the following examples are commercially available and can be purchased from the market. Below in conjunction with embodiment the present invention is described in further detail:

Example 1

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the proportion, the granulation particle size is 0.5mm, and dry at 100°C to obtain the sludge fiber granules with pores;

S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 1 hour, use a disc to granulate, the particle size is 4mm, and finally wrap the inorganic material on the outermost layer, cured for 1 hour to obtain aggregate pellets;

S3. Put the aggregate obtained in S2 into a rotary kiln for drying and calcination. In the first stage, the temperature is raised from room temperature to 100°C for 20 minutes at a speed of 1r/min; in the second stage, the temperature is raised from 100°C to 1050°C and The time is 30min, the speed is controlled at 4r/min, the material is discharged, cooled, mixed with organic silicon, and placed in a negative airtight pressure of 200kPa negative pressure for 1h to obtain lightweight aggregate.

Wherein, the weight of the organogel material is 5% of the weight of the industrial sludge;

The weight of described organosilicon is 1% of described industrial sludge weight;

The mass ratio of the straw fiber, industrial sludge (moisture 70%), and inorganic material is 20:60:5.

Example 2

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the proportion, the granulation particle size is 1mm, and dry at 110°C to obtain the sludge fiber granules with pores;

S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 2 hours, use a disc to granulate, the particle size is 4mm, and finally wrap the inorganic material on the outermost layer, cured for 2 hours to obtain aggregate pellets;

S3. Put the aggregate pellets obtained in S2 into a rotary kiln for drying and calcination. In the first stage, the temperature is raised from room temperature to 100°C for 25 minutes at a speed of 2r/min; in the second stage, the temperature is raised from 100°C to 1050°C and The time is 35 minutes, the rotation speed is controlled at 3r/min, after discharging and cooling, it is mixed with organic silicon, and placed in a negative airtight pressure of 400kPa for 0.8h to obtain lightweight aggregate.

Wherein, the weight of the organogel material is 8% of the weight of the industrial sludge;

The weight of described organosilicon is 1.5% of described industrial sludge weight;

The mass ratio of the straw fiber, industrial sludge (moisture 70%), and inorganic material is 22:65:8.

Example 3

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the proportion, the granulation particle size is 2mm, and dry at 120°C to obtain the sludge fiber granules with pores;

S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 3 hours, use a disc to granulate, the particle size is 6mm, and finally wrap the inorganic material on the outermost layer, cured for 3 hours to obtain aggregate pellets;

S3. Put the aggregate obtained in S2 into a rotary kiln for drying and calcination. In the first stage, the temperature is raised from room temperature to 100°C for 30 minutes at a speed of 2r/min; in the second stage, the temperature is raised from 100°C to 1050°C and The time is 40min, and the speed is controlled at 3r/min. After discharging and cooling, it is mixed with organic silicon, and placed in a negative airtight pressure of 500kPa for 0.5h to obtain lightweight aggregate.

Wherein, the weight of the organogel material is 6% of the weight of the industrial sludge;

The weight of described organosilicon is 2% of described industrial sludge weight;

The mass ratio of the straw fiber, industrial sludge (moisture 75%), and inorganic material is 25:70:10.

Comparative example 1

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the proportion, the granulation particle size is 0.5mm, and dry at 100°C to obtain the sludge fiber granules with pores;

S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 1 hour, use a disc to granulate, the particle size is 4mm, and finally wrap the inorganic material on the outermost layer, cured for 1 hour to obtain aggregate pellets;

S3. Put the aggregate obtained in S2 into a rotary kiln for drying and calcination. In the first stage, the temperature is raised from room temperature to 100°C for 20 minutes at a speed of 1r/min; in the second stage, the temperature is raised from 100°C to 1050°C and The time is 30min, the speed is controlled at 4r/min, the material is discharged, cooled, mixed with organic silicon, and placed in a negative airtight pressure of 200kPa negative pressure for 1h to obtain lightweight aggregate.

Wherein, the weight of the organogel material is 10% of the weight of the industrial sludge;

The weight of described organosilicon is 1% of described industrial sludge weight;

The mass ratio of the straw fiber, industrial sludge (moisture 70%), and inorganic material is 20:60:5.

Comparative example 2

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the proportion, the granulation particle size is 0.5mm, and dry at 100°C to obtain the sludge fiber granules with pores;

S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 1 hour, use a disc to granulate, the particle size is 4mm, and finally wrap the inorganic material on the outermost layer, cured for 1 hour to obtain aggregate pellets;

S3. Put the aggregate obtained in S2 into a rotary kiln for drying and calcination. In the first stage, the temperature is raised from room temperature to 100°C for 20 minutes at a speed of 1r/min; in the second stage, the temperature is raised from 100°C to 1050°C and The time is 30min, the speed is controlled at 4r/min, the material is discharged, cooled, mixed with organic silicon, and placed in a negative airtight pressure of 200kPa negative pressure for 1h to obtain lightweight aggregate.

Wherein, the weight of the organogel material is 2% of the weight of the industrial sludge;

The weight of described organosilicon is 1% of described industrial sludge weight;

The mass ratio of the straw fiber, industrial sludge (moisture 70%), and inorganic material is 20:60:5.

Comparative example 3

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the proportion, the granulation particle size is 0.5mm, and dry at 100°C to obtain the sludge fiber granules with pores;

S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 1 hour, use a disc to granulate, the particle size is 4mm, and finally wrap the inorganic material on the outermost layer, cured for 1 hour to obtain aggregate pellets;

S3. Put the aggregate obtained in S2 into a rotary kiln for drying and calcination. In the first stage, the temperature is raised from room temperature to 100°C for 20 minutes at a speed of 1r/min; in the second stage, the temperature is raised from 100°C to 1050°C and The time is 30min, the speed is controlled at 4r/min, and the lightweight aggregate is obtained after discharging and cooling.

Wherein, the weight of the organogel material is 5% of the weight of the industrial sludge;

The mass ratio of the straw fiber, industrial sludge (moisture 70%), and inorganic material is 20:60:5.

Comparative example 4

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the industrial sludge with the organic gel material evenly, maintain for 1 hour, use a disc to granulate, the particle size is 4mm, and finally wrap the inorganic material on the outermost layer, and maintain for 1 hour to obtain aggregate particles;

S2. Put the aggregate obtained in S1 into a rotary kiln for drying and calcination. In the first stage, the temperature is raised from room temperature to 100°C for 20 minutes at a speed of 1r/min; in the second stage, the temperature is raised from 100°C to 1050°C and the temperature is raised The time is 30min, the speed is controlled at 4r/min, the material is discharged, cooled, mixed with organic silicon, and placed in a negative airtight pressure of 200kPa negative pressure for 1h to obtain lightweight aggregate.

Wherein, the weight of the organogel material is 5% of the weight of the industrial sludge;

The weight of described organosilicon is 1% of described industrial sludge weight;

The mass ratio of the industrial sludge (70% moisture) to the inorganic material is 60:5.

Comparative example 5

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the proportion, the granulation particle size is 0.5mm, and dry at 100°C to obtain the sludge fiber granules with pores;

S2. First mix the remaining industrial sludge with the organic gel material evenly, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 1 hour, use a disc to granulate, the particle size is 4mm, and cure for 1 hour to obtain aggregate particles;

S3. Put the aggregate obtained in S2 into a rotary kiln for drying and calcination. In the first stage, the temperature is raised from room temperature to 100°C for 20 minutes at a speed of 1r/min; in the second stage, the temperature is raised from 100°C to 1050°C and The time is 30min, the speed is controlled at 4r/min, the material is discharged, cooled, mixed with organic silicon, and placed in a negative airtight pressure of 200kPa negative pressure for 1h to obtain lightweight aggregate.

Wherein, the weight of the organogel material is 5% of the weight of the industrial sludge;

The weight of described organosilicon is 1% of described industrial sludge weight;

The mass ratio of the straw fiber to industrial sludge (moisture 70%) is 20:60.

Comparative example 6

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix straw charcoal fiber, industrial sludge, organic gel material, inorganic material, and organic silicon according to the proportion, and the granulation particle size is 4mm to obtain aggregate granules;

S2. Put the aggregate pellets obtained in S1 into a rotary kiln for drying and calcination. The temperature is raised from 100°C to 1050°C. The heating time is 30min, and the speed is controlled at 4r/min. After discharging and cooling, lightweight aggregate is obtained. .

Wherein, the weight of the organogel material is 5% of the weight of the industrial sludge;

The weight of described organosilicon is 1% of described industrial sludge weight;

The mass ratio of the straw fiber, industrial sludge (moisture 70%), and inorganic material is 20:60:5.

Comparative example 7

A preparation process of lightweight aggregate, comprising the following specific steps:

S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the proportion, the granulation particle size is 0.5mm, and dry at 100°C to obtain the sludge fiber granules with pores;

S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 1 hour, use a disc to granulate, the particle size is 4mm, and finally wrap the inorganic material on the outermost layer, cured for 1 hour to obtain aggregate pellets;

S3. Put the aggregate particles obtained in S2 into a rotary kiln for drying and calcination. The temperature is directly raised from 400°C to 1050°C. The heating time is 30min, and the speed is controlled at 4r/min. After discharging and cooling, mix with organic silicon , and placed in a negative airtight pressure of 200kPa negative pressure for 1h to obtain lightweight aggregate.

Wherein, the weight of the organogel material is 5% of the weight of the industrial sludge;

The weight of described organosilicon is 1% of described industrial sludge weight;

The mass ratio of the straw fiber, industrial sludge (moisture 70%), and inorganic material is 20:60:5.

The properties of the lightweight aggregates prepared in each example and comparative example were tested using the method in GB/T17431-2010 "Lightweight Aggregate and Its Test Methods", and the results are shown in Table 1.

Table 1 Lightweight aggregate performance test results

As can be seen from the results in Table 1, the lightweight aggregate obtained by the preparation process of the present invention has a packing density of 0.58-0.63g/ ^cm3 , a strength of more than 8.5MPa, a low water absorption rate, and a porosity of up to 68.4%. , indicating that the obtained lightweight aggregate has loose structure, light weight, high strength and good stability.

In Comparative Example 1, the amount of organic gel material used reached 10% of the industrial sludge. Compared with Example 1, its porosity increased, and although the bulk density decreased, its strength also decreased greatly, and its water absorption increased, which was not conducive to The stability of subsequent use performance. In comparative example 2, the amount of organogel material used is only 2% of that of industrial sludge. Although the strength has been improved, the porosity has decreased significantly, and the bulk density has also greatly increased, indicating that the porosity is not enough.

In comparative example 3, no silicone was added, and other properties were not greatly affected, but its water absorption rate was greatly improved, which was not conducive to the stability of subsequent use performance.

In Comparative Example 4, no straw carbon fiber was added, and the bulk density and strength were greatly improved, but the porosity was low, that is, the structure was not loose enough to meet the requirements of lightweight aggregate.

In Comparative Example 5, no inorganic material was added, although its porosity, bulk density and water absorption performance were better, but its strength was significantly reduced, which was not conducive to subsequent use.

In Comparative Example 6, all raw materials were mixed at one time, the porosity decreased, and the bulk density increased. It is likely that the one-time mixing failed to form a layered structure, and the pores of straw carbon fibers were completely filled. In comparative example 7, in the subsequent rotary kiln calcination process, direct high-temperature calcination, because the temperature exceeds the boiling point of the organic gel, the surface inorganic materials are directly volatilized and washed out in large quantities without curing the organic gel, which greatly destroys the surface structure and directly affects The strength of the aggregate.

The lightweight aggregate obtained in Examples 1-3 was subjected to a harmful ion leaching test according to the GB5085.3 "Identification Standard for Hazardous Waste Leach Toxicity Identification", and the test results are shown in Table 2. The detection method is as follows: take 10 g of the obtained lightweight aggregate sample and put it into 100 mL of distilled water for 24 hours, shake and stir for 24 hours, then filter, and use atomic absorption spectrometry to detect harmful ions in the filtrate.

Table 2 Harmful ion leaching test results

From the results in Table 2, it can be seen that the leaching data of harmful ions in the lightweight aggregate prepared from wastes in the present invention fully meets the requirements of GB5085.3, is safe, can replace natural high-quality aggregate, and has market application value.

Finally, it should be emphasized that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the principles and principles shall be included within the protection scope of the present invention.

Claims (10)

1. A lightweight aggregate, characterized in that, the lightweight aggregate comprises the following raw material components: straw charcoal fiber, industrial sludge, inorganic material, organic gel material, organic silicon; The weight of the organogel material is 5-8% of the weight of the industrial sludge; The weight of the organosilicon is 1-2% of the weight of the industrial sludge; The mass ratio of the straw fiber, industrial sludge and inorganic material is 20-25:60-70:5-10. 2. A kind of lightweight aggregate according to claim 1, characterized in that, the straw charcoal fiber is obtained after the straw is dried, pulverized, dried, dry-distilled, and cooled in the charcoal-making equipment, and the straw The particle size of the carbon fiber is 100-120 mesh. 3. A kind of lightweight aggregate according to claim 1, characterized in that, the industrial sludge is the sludge after heavy removal treatment in a large industrial sewage station, and its moisture content is 70-75%. 4. A lightweight aggregate according to claim 1, characterized in that the inorganic material is a mixture of Portland cement and alumina in any proportion. 5. A lightweight aggregate according to claim 1, characterized in that the organic gelling material is one or more of polyvinyl alcohol, polyacrylamide, and polyurethane. 6. according to the preparation technology of a kind of lightweight aggregate described in any one of claim 1-5, it is characterized in that, comprising the following specific steps: S1. Mix the straw carbon fiber with 1/3 of the industrial sludge evenly according to the ratio, granulate, and dry quickly to obtain the sludge fiber granules with pores; S2. Mix the remaining industrial sludge with the organic gel material first, then add the sludge fiber particles obtained in S1 and mix evenly, cure for 1-3 hours, use a disc to granulate, and finally wrap the inorganic material on the outermost layer for curing 1-3h, get the aggregate pellets; S3. Put the aggregate particles obtained in S2 into a rotary kiln for drying and calcining. After cooling, mix them with organic silicon, and place them in a closed negative pressure state for 0.5-1h to obtain lightweight aggregates. 7. The preparation process of a lightweight aggregate according to claim 6, characterized in that, in S1, the granulation diameter is 0.5-2mm, and the drying temperature is 100-120°C; in S2, the granulation The diameter is 2-6mm. 8. The preparation process of a lightweight aggregate according to claim 6, characterized in that, in S3, the temperature of the rotary kiln is raised in two stages, the first stage starts from room temperature to 100°C, the temperature is raised for 20-30min, and the rotating speed The temperature is 1-2r/min; in the second stage, the temperature is raised from 100°C to 1050°C, the heating time is 30-40min, and the speed is controlled at 3-4r/min. 9. The preparation process of a lightweight aggregate according to claim 6, characterized in that, in S3, the pressure in the airtight negative pressure state is negative 200-500kPa. 10. An application of the lightweight aggregate according to any one of claims 1-5 in high-rise buildings, exterior walls, and long-span walls.