阅读说明：本技术 一种干法制粉静态烧结生产煤矸石陶粒的新工艺 (Novel process for producing coal gangue ceramsite by dry powder preparation and static sintering ) 是由 徐顺涛 姚长青 刘纯杰 郑灵棋 于 2021-08-17 设计创作，主要内容包括：本发明的实施例公开一种干法制粉静态烧结生产煤矸石陶粒的新工艺,属于煤矸石的综合利用的技术领域。所述新工艺的具体工艺流程先进行煤矸石的破碎和堆存均化,将均化好的煤矸石及辅料进行干法制粉,干法制粉得到的粉末在均化仓内储存均化,均化好的原料细粉增湿预混形成母粒,将母粒加水制成生坯陶粒,过筛获得合格的生球颗粒,铺底料及铺边料,之后将生球颗粒布料入台车,最后将布好料的台车经推车系统送入静态烧结隧道窑进行静态烧结生产煤矸石陶粒。本发明烧成段采用静态烧结,利用余热循环实现陶粒的干燥,焙烧段将陶粒均热段的热风作为二次风送入高温段进行再利用,助燃利用冷却一段余热作为助燃风,提高了助燃风温,节约了燃气能耗。(The embodiment of the invention discloses a novel process for producing coal gangue ceramsite by dry powder preparation and static sintering, belonging to the technical field of comprehensive utilization of coal gangue. The specific process flow of the new process comprises the steps of firstly crushing and stockpiling homogenization of the coal gangue, carrying out dry-process powder preparation on the homogenized coal gangue and auxiliary materials, storing and homogenizing powder obtained by the dry-process powder preparation in a homogenizing bin, humidifying and premixing homogenized raw fine powder to form master batches, adding water into the master batches to prepare green ceramsite, sieving to obtain qualified green pellets, paving a bottom material and a side material, then distributing the green pellets into a trolley, and finally conveying the trolley with the distributed raw material into a static sintering tunnel kiln through a trolley system to carry out static sintering to produce the coal gangue ceramsite. The sintering section of the invention adopts static sintering, realizes the drying of the ceramsite by utilizing the circulation of waste heat, and the hot air of the uniform heating section of the ceramsite is used as secondary air to be sent into the high temperature section for recycling in the sintering section, and the waste heat of the cooling section is used as combustion-supporting air for supporting combustion, thereby improving the temperature of the combustion-supporting air and saving the energy consumption of fuel gas.)

1. A new process for producing coal gangue ceramsite by dry powder preparation and static sintering is characterized by comprising the following steps:

s1, crushing, stockpiling and homogenizing, and performing dry milling on the homogenized coal gangue and auxiliary materials to obtain coal gangue powder;

s2, storing and homogenizing the coal gangue powder in a homogenizing bin to obtain raw material fine powder;

s3, humidifying and premixing the raw material fine powder to form master batches, adding water into the master batches to prepare green ceramic granules, and sieving to obtain green spherical granules;

s4, paving bottom materials and edge materials on the trolley, distributing the green pellets into the trolley, and conveying the trolley into a static sintering tunnel kiln through a trolley system for static sintering to obtain the coal gangue ceramsite.

2. The new process for producing the coal gangue ceramsite by the dry pulverizing and static sintering process as claimed in claim 1, wherein the coal gangue is crushed in S1 into small pieces with a particle size of less than or equal to 50mm before use.

3. The new process for producing coal gangue ceramsite by dry pulverizing and static sintering according to claim 1, wherein stacking homogenization in S1 is performed by stacking and leveling with stacking and reclaiming equipment in a layered manner, and vertical reclaiming is performed when in use.

4. The new process for producing coal gangue ceramsite by dry milling and static sintering according to claim 1, wherein the dry milling in S1 comprises the steps of respectively feeding homogenized coal gangue and auxiliary materials into different feeders, proportionally mixing the coal gangue and the auxiliary materials by an electronic batching device, and feeding the mixed coal gangue and the auxiliary materials into a mill for dry milling; grinding to a fineness of 3-5% of the residue after 250 mesh sieve, and controlling the water content within 1.5%.

5. The new process for producing coal gangue ceramsite by dry milling and static sintering according to claim 1, wherein the moisture content of the master batch in the S3 is 2-4%.

6. The new process for producing coal gangue ceramsite by dry pulverizing and static sintering as claimed in claim 1, wherein the green ceramsite in S3 is 8-20mm in diameter and 12-16% in water content.

7. The new process for producing coal gangue ceramsite by dry pulverizing and static sintering according to claim 1, wherein the thickness of the bed charge and the edge charge in S4 is 30-100 mm.

8. The new process for producing the coal gangue ceramsite by dry pulverizing and static sintering according to claim 1, wherein the static sintering tunnel kiln in the S4 comprises an air blowing drying section, an air draft drying section, a preheating section, a sintering section, a soaking section, a quenching section and a cooling section which are sequentially arranged in front and at the back.

9. The new process for producing coal gangue ceramsite by dry pulverizing and static sintering as claimed in claim 8, wherein the heat of the forced air drying section is derived from the waste heat generated by slow cooling of ceramsite at 200 ℃ and 250 ℃, and the treatment time is 10-16 minutes; the heat of the air draft drying section is derived from the waste heat of 250-350 ℃ generated in the sintering section, and the treatment time is 10-16 minutes; the waste heat of the quenching section is sent into a firing section through a pipeline at the top of the kiln, firing guns are arranged on two sides of the firing section, the temperature is heated to 1080 ℃ of the firing temperature of the ceramsite, and the treatment time is 22-35.2 minutes; a decarbonization zone is arranged in the preheating section, the temperature is 600-950 ℃, and the time is 16-25.6 minutes, so that the redundant carbon in the coal gangue ceramsite is removed, and the sintering quality of the coal gangue ceramsite is ensured; the temperature of the soaking section is 1080 ℃, and the soaking time is 6-9.6 minutes; the rapid cooling section rapidly cools the sintered ceramsite to 600 ℃ at a speed of 0.16-0.31 ℃/s so as to facilitate the formation of quartz crystals; the slow cooling section cools the ceramsite to about normal temperature at a speed of 0.59-0.94 ℃/s, so that the sieving, grading and packaging of the ceramsite are facilitated.

10. The novel process for producing coal gangue ceramsite by dry pulverizing and static sintering according to any one of claims 1-9, wherein the coal gangue ceramsite has a cylinder pressure strength of 6.5MPa or more and a bulk density of 0.8-1.1g/cm³Apparent density of 1.65-1.80g/cm³(ii) a The coal gangue ceramsite is classified into three grades of 5mm below, 5-10mm and 10-20mm through screening.

Technical Field

The invention belongs to the technical field of comprehensive utilization of coal gangue, and relates to a novel process for producing coal gangue ceramsite by dry powder preparation and static sintering.

Background

The coal gangue is a co-associated mineral of coal, is solid waste which is low in calorific value and hard in texture and is discharged in the processes of coal mining and washing processing, the calorific value of the solid waste is generally lower than 6.3MJ/kg, and the solid waste contains Al₂O₃、SiO₂And Fe₂O₃The total content of the inorganic ash content reaches 60-95% of the total amount of the coal gangue, and the inorganic ash content also contains CaO, MgO and Na with different quantities₂O、K₂O、P₂O₅、SO₃And trace rare elements (gallium, vanadium, titanium, cobalt). Generally, 0.15-0.2 ton of coal gangue is produced per 1 ton of raw coal.

The accumulated stockpiling amount of coal gangue in China exceeds 50 hundred million tons, the occupied land is about 20 more than ten thousand mu, the coal gangue is increased by 6.5 million tons each year, and the comprehensive utilization rate is less than 70 percent. At present, the method is industrial solid waste with the largest stockpiling amount and annual output and the largest occupied land for stockpiling in China.

At present, the treatment mode mainly adopts landfill and stockpiling, and a small part of the treatment mode is used for burning bricks, tiles, light aggregates, burning power generation and the like.

The traditional production process of the coal gangue ceramsite mainly adopts a rotary kiln, and has the defects of low yield and high energy consumption, and the production of 1t of ceramsite consumes 50m of natural gas³In the above way, the daily production capacity of one production line is about 300t at most, and the massive treatment of the coal gangue is difficult to realize.

The chinese patent CN 113105258A relates to a method for preparing undoped single coal gangue ceramsite based on a moving bed, wherein the moving bed is a horizontally moving grate, the grate is sequentially divided into a drying section, a preheating section, a roasting section, a cooling section i and a cooling section ii from a feeding port to a discharging port, and it is obvious that the homogenization of coal gangue, the prolonged service life of side bottom materials and the quality of sintered ceramsite are not considered.

The Chinese patent CN 112521174A relates to a preparation method of coal gangue ceramsite, because the dried material enters a rotary kiln for calcination, and the temperature treatment after coal gangue homogenization and calcination is not carried out, the prepared ceramsite has uneven quality, low production capacity and poor treatment capability.

Disclosure of Invention

The invention solves the technical problems that in the traditional preparation process of the coal gangue ceramsite, the production capacity of a rotary kiln is low, the consumption of natural gas is high, the loss of a conveying plate of a chain grate machine is large, the quality of the used coal gangue raw material green ceramsite is uneven, and the quality of the produced coal gangue ceramsite changes greatly from top to bottom.

In order to solve the technical problems, the invention provides a novel process for producing coal gangue ceramsite by dry powder preparation and static sintering, which comprises the following steps:

s1, crushing, stockpiling and homogenizing, and performing dry milling on the homogenized coal gangue and auxiliary materials to obtain coal gangue powder;

s2, storing and homogenizing the coal gangue powder in a homogenizing bin to obtain raw material fine powder;

s3, humidifying and premixing the raw material fine powder to form master batches, adding water into the master batches to prepare green ceramic granules, and sieving to obtain green spherical granules;

s4, paving bottom materials and edge materials on the trolley, distributing the green pellets into the trolley, and conveying the trolley into a static sintering tunnel kiln through a trolley system for static sintering to obtain the coal gangue ceramsite.

Preferably, the coal gangue crushed in the S1 is crushed into small blocks with the granularity less than or equal to 50mm before use.

Preferably, in the step S1, stacking homogenization is performed by layering stacking and reclaiming equipment, and a vertical direction is adopted for reclaiming materials when in use.

Preferably, the dry milling in S1 is to respectively load the homogenized coal gangue and auxiliary materials into different feeders, and proportionally mix them by an electronic batching device and send them into a mill for dry milling; grinding to a fineness of 3-5% of the residue after 250 mesh sieve, and controlling the water content within 1.5%.

Preferably, the raw material which is ground to fineness by the dry method is collected by cloth bag dust removal and is conveyed into a homogenizing bin S2 by a conveying system for storage and homogenization.

Preferably, the moisture content of the master batch in the S3 reaches 2-4%.

Preferably, the moisture of the master batch in the step S3 is controlled by feeding the homogenized fine raw material powder into a humidifying premixing device (EG2400) through a metering screw for humidifying and premixing, so as to achieve the effect of humidifying and dedusting to form the master batch.

Preferably, the green ceramsite in the S3 is a green ceramsite which has the diameter of 8-20mm and contains 12-16% of water.

Preferably, unqualified green ball particles are screened out by a multi-roller screen, then the green ball particles are uniformly distributed into a firing trolley in S4, and a bedding material and a rim charge of 30-100mm are added into the firing trolley before the green balls are distributed into the firing trolley; the specification of the firing trolley can be determined according to the output requirement of a user, and the daily treatment capacity can reach more than kiloton.

Preferably, the thickness of the bottom layer and the edge layer in the step S4 is 30-100mm, and the bottom layer and the edge layer are sintered ceramic particles, so as to protect the trolley and prolong the service life.

Preferably, the static sintering tunnel kiln in the S4 includes a blowing drying section, an exhausting drying section, a preheating section, a firing section, a soaking section, a quenching section and a cooling section which are sequentially arranged in series.

Preferably, the heat of the forced air drying section is derived from the afterheat of the ceramsite slow cooling at the temperature of 200 ℃ and 250 ℃, and the treatment time is 10-16 minutes; the heat of the air draft drying section is derived from the waste heat of 250-350 ℃ generated in the sintering section, and the treatment time is 10-16 minutes; the waste heat of the quenching section is sent into a firing section through a pipeline at the top of the kiln, firing guns are arranged on two sides of the firing section, the temperature is heated to 1080 ℃ of the firing temperature of the ceramsite, and the treatment time is 22-35.2 minutes; a decarbonization zone is arranged in the preheating section, the temperature is 600-950 ℃, and the time is 16-25.6 minutes, so that the redundant carbon in the coal gangue ceramsite is removed, and the sintering quality of the coal gangue ceramsite is ensured; the temperature of the soaking section is 1080 ℃, and the soaking time is 6-9.6 minutes; the rapid cooling section rapidly cools the sintered ceramsite to 600 ℃ at a speed of 0.16-0.31 ℃/s so as to facilitate the formation of quartz crystals; the slow cooling section cools the ceramsite to about normal temperature at a speed of 0.59-0.94 ℃/s, so that the sieving, grading and packaging of the ceramsite are facilitated.

Preferably, in the static firing of the ceramsite, hot air passes through the ceramsite, the ceramsite is fired from top to bottom, and finally the uniform temperature section is achieved, wherein the surface and the inside are the same.

Preferably, the coal gangue ceramsite has the cylinder pressure strength of more than 6.5MPa and the bulk density of 0.8-1.1g/cm³Apparent density of 1.65-1.80g/cm³(ii) a The coal gangue ceramsite is classified into three grades of 5mm below, 5-10mm and 10-20mm through screening.

The technical scheme provided by the embodiment of the invention at least has the following beneficial effects:

(1) in the method, hot air passes through the ceramsite from top to bottom in the static firing of the ceramsite, and the uniform heating section achieves uniform heat of the ceramsite.

(2) The stockpiling homogenization and the storage homogenization of the invention ensure that the granularity and the moisture of the coal gangue are controlled more accurately, and lay a foundation for the subsequent structure and performance control of the coal gangue ceramsite.

(3) The moisture of the master batch is accurately controlled by feeding homogenized raw material fine powder into a humidifying premixing device (EG2400) through a metering screw for humidifying and premixing.

(4) The bedding material and the edge material are sintered ceramic grains and aim to protect the trolley and prolong the service life.

(5) The arrangement of the blast drying section, the air draft drying section, the preheating section, the sintering section, the soaking section, the quenching section and the slow cooling section of the static sintering tunnel kiln and the arrangement of the trolley ensure that the daily treatment capacity can reach more than kiloton grade, which is more than 3 times of that of the traditional method, thereby being beneficial to industrial large-scale production and popularization.

(6) The heat of each section is effectively utilized, the production cost is saved, and compared with the prior art, the heat control and the high-efficiency utilization among the sections can further improve the quality of the sintered gangue ceramsite on the basis of improving the daily treatment capacity.

In conclusion, the firing section of the invention adopts static sintering, the waste heat circulation is utilized to realize the drying of the ceramsite, the hot air in the uniform heating section of the ceramsite is used as secondary air to be sent to the high temperature section for recycling in the firing section, and the waste heat in the cooling section is used as combustion-supporting air for combustion supporting, so that the temperature of the combustion-supporting air is improved, and the energy consumption of fuel gas is saved.

In a word, the process and the equipment are simple, the occupied area is small, the energy consumption is low, the treatment capacity is large, the comprehensive treatment of massive solid wastes such as coal gangue is very suitable, and the 'drying and squeezing' of the coal gangue can be realized.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a process flow diagram of a new process for producing coal gangue ceramsite by dry pulverizing and static sintering according to the present invention;

FIG. 2 is a hot air circulation diagram of static sintering in a static sintering tunnel kiln of the new process for producing coal gangue ceramsite by dry pulverizing and static sintering.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

As shown in figures 1 and 2, the invention provides a new process for producing coal gangue ceramsite by dry powder preparation and static sintering, which comprises the following steps:

s1, crushing, stockpiling and homogenizing, and performing dry milling on the homogenized coal gangue and auxiliary materials to obtain coal gangue powder;

s2, storing and homogenizing the coal gangue powder in a homogenizing bin to obtain raw material fine powder;

s3, humidifying and premixing the raw material fine powder to form master batches, adding water into the master batches to prepare green ceramic granules, and sieving to obtain green spherical granules;

s4, paving bottom materials and edge materials on the trolley, distributing the green pellets into the trolley, and conveying the trolley into a static sintering tunnel kiln through a trolley system for static sintering to obtain the coal gangue ceramsite.

In particular, the coal gangue crushed in the S1 is crushed into small blocks with the granularity less than or equal to 50mm before use.

In particular, in the step S1, stacking homogenization is performed by layering stacking and reclaiming equipment, and a vertical direction is adopted for reclaiming materials when in use.

Particularly, the dry milling in the S1 is to respectively load the homogenized coal gangue and auxiliary materials into different feeders, and proportionally mix the materials by an electronic batching device and send the materials into a mill for dry milling; grinding to a fineness of 3-5% of the residue after 250 mesh sieve, and controlling the water content within 1.5%.

Particularly, the raw materials which are ground to be fine by the dry method are collected by cloth bag dust removal and are sent into a homogenizing silo S2 by a conveying system for storage and homogenization.

Particularly, the moisture content of the master batch in the S3 reaches 2-4%.

Particularly, the moisture of the master batch in the S3 is controlled by feeding the homogenized raw material fine powder into a humidifying premixing device (EG2400) through a metering screw for humidifying and premixing, so as to achieve the effect of humidifying and dedusting to form the master batch.

Particularly, the green ceramsite in the S3 is a green ceramsite which has the diameter of 8-20mm and contains 12-16% of water.

Particularly, unqualified green ball particles are screened out by a multi-roller screen, then the green ball particles are uniformly distributed into a firing trolley in S4, and a bedding material and a rim charge of 30-100mm are added into the firing trolley before the green balls are distributed into the firing trolley; the specification of the firing trolley can be determined according to the output requirement of a user, and the daily treatment capacity can reach more than kiloton.

Particularly, the thickness of the bottom layer and the edge layer in the step S4 is 30-100mm, and the bottom layer and the edge layer are sintered ceramic grains and are used for protecting the trolley and prolonging the service life.

Particularly, the static sintering tunnel kiln comprises a blast drying section, an air draft drying section, a preheating section, a sintering section, a soaking section, a quenching section and a slow cooling section which are sequentially arranged in front and back.

Particularly, the heat of the forced air drying section is derived from the afterheat of the ceramsite slow cooling at the temperature of 200 ℃ and 250 ℃, and the treatment time is 10-16 minutes; the heat of the air draft drying section is derived from the waste heat of 250-350 ℃ generated in the sintering section, and the treatment time is 10-16 minutes; the waste heat of the quenching section is sent into a firing section through a pipeline at the top of the kiln, firing guns are arranged on two sides of the firing section, the temperature is heated to 1080 ℃ of the firing temperature of the ceramsite, and the treatment time is 22-35.2 minutes; a decarbonization zone is arranged in the preheating section, the temperature is 600-950 ℃, and the time is 16-25.6 minutes, so that the redundant carbon in the coal gangue ceramsite is removed, and the sintering quality of the coal gangue ceramsite is ensured; the temperature of the soaking section is 1080 ℃, and the soaking time is 6-9.6 minutes; the rapid cooling section rapidly cools the sintered ceramsite to 600 ℃ at a speed of 0.16-0.31 ℃/s so as to facilitate the formation of quartz crystals; the slow cooling section cools the ceramsite to about normal temperature at a speed of 0.59-0.94 ℃/s, so that the sieving, grading and packaging of the ceramsite are facilitated.

Particularly, in the static firing of the ceramsite, hot air passes through the ceramsite, the ceramsite is fired from top to bottom, and finally the uniform temperature section is achieved, wherein the upper part and the lower part are consistent, and the surface and the inner part are the same.

Particularly, the cylinder pressure strength of the coal gangue ceramsite is more than 6.5MPa, and the bulk density is 0.8-1.1g/cm³Apparent density of 1.65-1.80g/cm³(ii) a The coal gangue ceramsite is classified into three grades of 5mm below, 5-10mm and 10-20mm through screening.

The new process for producing the coal gangue ceramsite by dry powder preparation and static sintering is described by combining the following embodiment and the attached drawings 1-2:

example 1

The daily throughput of 166m was prepared according to the process scheme shown in FIG. 1³Coal gangue ceramsite

Before use, the coal gangue is crushed into small blocks with the granularity less than or equal to 50mm, stacking and homogenizing are carried out by adopting stacking and taking equipment for layering and tiling, and material is taken in the vertical direction when in use.

Carrying out dry powder preparation on the homogenized coal gangue and auxiliary materials: the homogenized coal gangue and the auxiliary materials are respectively loaded into different feeding machines and are mixed and fed into a vertical mill for dry grinding according to a proportion through an electronic batching device. Grinding to 250 mesh (mesh aperture 58 μm), and sieving with 2.5% (weight percentage of the rest sample on the sieve) to control water content at 1 + -0.5%.

The raw materials which are ground to be fine are collected by cloth bag dust removal and are sent into a homogenizing silo by a conveying system for storage and homogenization.

The homogenized fine powder of the raw materials is fed into a humidifying premixing device (EG2400) through a metering screw for humidifying and premixing, and the moisture reaches 3.0 percent so as to achieve the effect of humidifying and dedusting to form master batches.

The pre-humidified master batch containing 3.0% of water is conveyed to a granulating disc by conveying equipment, further water is added to prepare green ceramsite with the diameter of 8mm and the water content of 12%, unqualified green pellet particles are sieved by a multi-roller sieve and then uniformly distributed to a firing trolley, 50mm of bottom material and edge material are laid on the trolley before the green pellets are distributed, and the raw material is the fired ceramsite and aims to protect the trolley and prolong the service life. The trolley specification can be determined according to the user output requirement, and the daily throughput can reach more than kiloton.

As shown in fig. 2, after the material is distributed by the trolley according to the output requirement of a user, the trolley is sent into a static sintering tunnel kiln, and is sequentially treated by an air blast drying section, an air draft drying section, a preheating section, a firing section, a soaking section, a quenching section and a slow cooling section, so that the coal gangue ceramsite meeting the requirement is finally prepared.

Wherein the heat of the forced air drying section is derived from the waste heat generated by slow cooling of the ceramsite at the temperature of 200 ℃, and the treatment time is 10 minutes; the heat of the air draft drying section is derived from the 250 ℃ waste heat generated by the firing section, and the treatment time is 10 minutes; the waste heat of the quenching section is sent into a firing section through a pipeline at the top of the kiln, firing guns are arranged on two sides of the firing section, the temperature is heated to 1080 ℃ of the firing temperature of the ceramsite, and the treatment time is 22 minutes; a decarbonization zone is arranged in the preheating section, the temperature is 600 ℃, and the time is 16 minutes, so that the redundant carbon in the coal gangue ceramsite is removed, and the sintering quality of the coal gangue ceramsite is ensured; the temperature of the soaking section is 1080 ℃, and the soaking time is 6 minutes; the sintered ceramsite is rapidly cooled to 600 ℃ by the quenching section at the speed of 0.31 ℃/S so as to facilitate the formation of quartz crystals; the slow cooling section cools the ceramsite to about normal temperature at the speed of 0.94 ℃/s, so that the sieving, grading and packaging of the ceramsite are facilitated.

In the static firing of the ceramsite, hot air passes through the ceramsite, the ceramsite is fired from top to bottom, and finally the upper part and the lower part of the ceramsite are consistent in a soaking section, and the surface and the inside of the ceramsite are consistent.

The properties of the sintered coal gangue ceramsite are as follows: the cylinder pressure is 7.2MPa, and the bulk density is 0.97g/cm³Apparent density of 1.72g/cm³。

The sintered ceramsite is sieved into three grades of less than 5mm, 5-10mm and 10-20mm, and the three grades are respectively packaged and put in storage.

Example 2

The daily throughput of 138m was prepared according to the process flow shown in FIG. 1³Coal gangue ceramsite

Before use, the coal gangue is crushed into small blocks with the granularity less than or equal to 50mm, stacking and homogenizing are carried out by adopting stacking and taking equipment for layering and tiling, and material is taken in the vertical direction when in use.

Carrying out dry powder preparation on the homogenized coal gangue and auxiliary materials: the homogenized coal gangue and the auxiliary materials are respectively loaded into different feeding machines and are mixed and fed into a vertical mill for dry grinding according to a proportion through an electronic batching device. Grinding to 250 mesh (mesh aperture 58 μm), sieving residue 3 + -1% (weight percentage of the rest sample on the sieve), and controlling water content at 1 + -0.5%.

The raw materials which are ground to be fine are collected by cloth bag dust removal and are sent into a homogenizing silo by a conveying system for storage and homogenization.

The homogenized fine powder of the raw materials is fed into a humidifying premixing device (EG2400) through a metering screw for humidifying and premixing, and the moisture reaches 3.5% so as to achieve the effect of humidifying and dedusting to form master batches.

The pre-humidified master batch containing 3.5% of water is conveyed to a granulating disc by conveying equipment, further water is added to prepare green ceramsite with the diameter of 15mm and the water content of 14%, unqualified green pellet particles are sieved by a multi-roller sieve and then uniformly distributed to a firing trolley, a bedding material and a rim charge with the diameter of 80mm are added to the trolley before the green pellets are distributed to the firing trolley, the raw material is the fired ceramsite, and the purpose is to protect the trolley to prolong the service life. The trolley specification can be determined according to the user output requirement, and the daily throughput can reach more than kiloton.

As shown in fig. 2, after the material is distributed by the trolley according to the output requirement of a user, the trolley is sent into a static sintering tunnel kiln, and is sequentially treated by an air blast drying section, an air draft drying section, a preheating section, a firing section, a soaking section, a quenching section and a slow cooling section, so that the coal gangue ceramsite meeting the requirement is finally prepared.

Wherein the heat of the forced air drying section is derived from the afterheat of the ceramsite generated by slow cooling at the temperature of 250 ℃, and the treatment time is 12 minutes; the heat of the air draft drying section is derived from the waste heat of 350 ℃ generated by the firing section, and the treatment time is 12 minutes; the waste heat of the quenching section is sent to a firing section through a pipeline at the top of the kiln, firing guns are arranged on two sides of the firing section, the temperature is heated to 1080 ℃ of the firing temperature of the ceramsite, and the treatment time is 26.4 minutes; a decarbonization zone is arranged in the preheating section, the excess carbon in the coal gangue ceramsite is decarbonized at 950 ℃ for 19.2 minutes, so that the sintering quality of the coal gangue ceramsite is ensured; the temperature of the soaking section is 1080 ℃, and the soaking time is 7.2 minutes; the sintered ceramsite is rapidly cooled to 600 ℃ by the quenching section at the speed of 0.26 ℃/s so as to facilitate the formation of quartz crystals; the slow cooling section cools the ceramsite to about normal temperature at the speed of 0.59 ℃/s, so that the sieving, grading and packaging of the ceramsite are facilitated.

In the static firing of the ceramsite, hot air passes through the ceramsite, the ceramsite is fired from top to bottom, and finally the upper part and the lower part of the ceramsite are consistent in a soaking section, and the surface and the inside of the ceramsite are consistent.

The properties of the sintered coal gangue ceramsite are as follows: cylinder pressure strength of 9.1MPa or more and bulk density of 1.00g/cm³Apparent density of 1.76g/cm³。

The sintered ceramsite is sieved into three grades of less than 5mm, 5-10mm and 10-20mm, and the three grades are respectively packaged and put in storage.

Example 3

The daily throughput of 104m is prepared according to the process flow shown in FIG. 1³Coal gangue ceramsite

Before use, the coal gangue is crushed into small blocks with the granularity less than or equal to 50mm, stacking and homogenizing are carried out by adopting stacking and taking equipment for layering and tiling, and material is taken in the vertical direction when in use.

Carrying out dry powder preparation on the homogenized coal gangue and auxiliary materials: the homogenized coal gangue and the auxiliary materials are respectively loaded into different feeding machines and are mixed and fed into a vertical mill for dry grinding according to a proportion through an electronic batching device. Grinding to 250 mesh (mesh aperture 58 μm), sieving residue 3 + -1% (weight percentage of the rest sample on the sieve), and controlling water content at 1 + -0.5%.

The raw materials which are ground to be fine are collected by cloth bag dust removal and are sent into a homogenizing silo by a conveying system for storage and homogenization.

The homogenized fine powder of the raw materials is fed into a humidifying premixing device (EG2400) through a metering screw for humidifying and premixing, and the moisture content reaches 4% so as to achieve the effect of humidifying and dedusting to form master batches.

Conveying the pre-humidified master batch containing 4% of water to a granulating disc by a conveying device, further adding water to prepare green ceramsite with the diameter of 20mm and the water content of 16%, screening out unqualified green pellet particles by a multi-roller screen, uniformly distributing the green pellet particles to a firing trolley, and walking 100mm of bedding materials and edge materials into the trolley before the green pellets are distributed, wherein the raw material is the fired ceramsite and aims to protect the trolley and prolong the service life. The trolley specification can be determined according to the user output requirement, and the daily throughput can reach more than kiloton.

As shown in fig. 2, after the material is distributed by the trolley according to the output requirement of a user, the trolley is sent into a static sintering tunnel kiln, and is sequentially treated by an air blast drying section, an air draft drying section, a preheating section, a firing section, a soaking section, a quenching section and a slow cooling section, so that the coal gangue ceramsite meeting the requirement is finally prepared.

Wherein the heat of the forced air drying section is derived from the afterheat of the ceramsite generated by slow cooling at 220 ℃, and the treatment time is 16 minutes; the heat of the air draft drying section is derived from 290 ℃ waste heat generated by the firing section, and the treatment time is 16 minutes; the waste heat of the quenching section is sent to a firing section through a pipeline at the top of the kiln, firing guns are arranged on two sides of the firing section, the temperature is heated to 1080 ℃ of the firing temperature of the ceramsite, and the treatment time is 35.2 minutes; a decarbonization zone is arranged in the preheating section, and redundant carbon in the coal gangue ceramsite is decarbonized at 720 ℃ for 25.6 minutes so as to ensure the firing quality of the coal gangue ceramsite; the temperature of the soaking section is 1080 ℃, and the soaking time is 9.6 minutes; the sintered ceramsite is rapidly cooled to 600 ℃ by the quenching section at the speed of 0.16 ℃/s so as to form quartz crystals; the slow cooling section cools the ceramsite to about normal temperature at the speed of 0.59 ℃/s, so that the sieving, grading and packaging of the ceramsite are facilitated.

In the static firing of the ceramsite, hot air passes through the ceramsite, the ceramsite is fired from top to bottom, and finally the upper part and the lower part of the ceramsite are consistent in a soaking section, and the surface and the inside of the ceramsite are consistent.

The properties of the sintered coal gangue ceramsite are as follows: the cylinder pressure strength is more than 10.2MPa, and the bulk density is 1.02g/cm³Apparent density of 1.79g/cm³。

The sintered ceramsite is sieved into three grades of less than 5mm, 5-10mm and 10-20mm, and the three grades are respectively packaged and put in storage.

In summary, the technical solution provided by the embodiment of the present invention at least has the following beneficial effects:

(1) in the method, hot air passes through the ceramsite from top to bottom in the static firing of the ceramsite, and the uniform heating section achieves uniform heat of the ceramsite.

(2) The stockpiling homogenization and the storage homogenization of the invention ensure that the granularity and the moisture of the coal gangue are controlled more accurately, and lay a foundation for the subsequent structure and performance control of the coal gangue ceramsite.

(3) The moisture of the master batch is accurately controlled by feeding homogenized raw material fine powder into a humidifying premixing device (EG2400) through a metering screw for humidifying and premixing.

(4) The bedding material and the edge material are sintered ceramic grains and aim to protect the trolley and prolong the service life.

(5) The arrangement of the blast drying section, the air draft drying section, the preheating section, the sintering section, the soaking section, the quenching section and the slow cooling section of the static sintering tunnel kiln and the arrangement of the trolley ensure that the daily treatment capacity can reach more than kiloton grade, which is more than 3 times of that of the traditional method, thereby being beneficial to industrial large-scale production and popularization.

(6) The heat of each section is effectively utilized, the production cost is saved, and compared with the prior art, the heat control and the high-efficiency utilization among the sections can further improve the quality of the sintered gangue ceramsite on the basis of improving the daily treatment capacity.

In conclusion, the firing section of the invention adopts static sintering, the waste heat circulation is utilized to realize the drying of the ceramsite, the hot air in the uniform heating section of the ceramsite is used as secondary air to be sent to the high temperature section for recycling in the firing section, and the waste heat in the cooling section is used as combustion-supporting air for combustion supporting, so that the temperature of the combustion-supporting air is improved, and the energy consumption of fuel gas is saved.

In a word, the process and the equipment are simple, the occupied area is small, the energy consumption is low, the treatment capacity is large, the comprehensive treatment of massive solid wastes such as coal gangue is very suitable, and the 'drying and squeezing' of the coal gangue can be realized.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.