阅读说明：本技术 一种发泡轻质耐高温的硅藻土保温砖制备方法 (Preparation method of foamed lightweight high-temperature-resistant diatomite insulating brick ) 是由 傅立民 于 2020-12-07 设计创作，主要内容包括：本发明公开了一种发泡轻质耐高温的硅藻土保温砖制备方法。首先去除硅藻土中的有机杂质,将硅藻土高温热定型,然后用自动生产线将硅藻土粉料、高铝水泥、高温辅料混掺入水发泡体系中,制成泡沫浆料,浇筑轻质耐高温硅藻土保温砖,短时间内硬固化成型,即时脱模搬动码放,少时干燥整形出厂。通过整治创新升级,采用新颖材料配方,改造硅藻土保温砖为发泡生产制造工艺,高效的自动机械成型制砖工艺生产线,环保清洁精密的整砖机械,增加了品种,提高了保温砖质量,提高了产量,降低了成本,创收了巨大的经济利益。(The invention discloses a preparation method of a foamed lightweight high-temperature-resistant diatomite insulating brick. Removing organic impurities in diatomite, carrying out high-temperature heat setting on the diatomite, mixing diatomite powder, high-alumina cement and high-temperature auxiliary materials into a water foaming system by using an automatic production line to prepare foam slurry, pouring a light high-temperature-resistant diatomite insulating brick, carrying out hard curing molding in a short time, carrying out immediate demolding, stacking, drying at a small time, shaping and leaving the factory. Through renovation, innovation and upgrading, a novel material formula is adopted, the diatomite insulating brick is transformed into a foaming production and manufacturing process, an efficient automatic mechanical forming brick making process production line and an environment-friendly, clean and precise brick shaping machine are adopted, the variety is increased, the quality of the insulating brick is improved, the yield is improved, the cost is reduced, and huge economic benefits are created.)

1. The preparation method of the foamed lightweight high-temperature-resistant diatomite insulating brick is characterized by comprising the following steps of:

1) adding a forming binder and water into the calcined and shaped diatomite to prepare a raw material of the insulating brick; the mass content of diatomite in the raw materials of the insulating brick is 15-80%, the mass content of a forming binder is 10-70%, and the mass content of water is 10-35%;

2) dissolving a foaming agent and a foam stabilizer in water, introducing compressed air, and stirring to form bubbles; adding air bubbles into the mixed raw materials of the insulating brick, and stirring to obtain the insulating brick with the volume density of 0.4-1.2g/cm²Fluid diatomite cement foam slurry;

3) and (3) injecting the flowing diatomite cement foam slurry into a brick making production line transmission mould, automatically condensing, curing and forming within 10-60min to obtain a wet green brick, and demoulding, dehydrating and drying the wet green brick to obtain the insulating brick.

2. The method for preparing the foamed lightweight high temperature resistant diatomite insulating brick as claimed in claim 1, wherein the insulating brick obtained in step 3) is subjected to secondary high temperature setting, wherein the temperature of the secondary high temperature setting is 1000-1300 ℃, and the setting time is 30-60 min.

3. The preparation method of the foamed lightweight high temperature resistant diatomite insulation brick according to claim 1, wherein the preparation method of the calcined and shaped diatomite comprises the following steps: pulverizing into 100-mesh 400-mesh diatomite powder, feeding into a rotary kiln, adding biomass fuel, and calcining by using liquefied natural gas as a calcining heat source; the calcination temperature is controlled at 200-950 ℃, and the calcination time is 30-60 min; and wherein the combustion time in the temperature interval of 850-950 ℃ must be guaranteed to be not less than 20 min; and cooling and discharging after the calcination is finished.

4. The preparation method of the foamed lightweight high temperature resistant diatomite insulating brick according to claim 1, wherein the step 1) further comprises a step of adding a high temperature auxiliary material and a quick setting reinforcing agent into the insulating brick raw material, wherein the high temperature auxiliary material accounts for 10-70% of the insulating brick raw material by mass, and the quick setting reinforcing agent accounts for 2-18% of the insulating brick raw material by mass.

5. The preparation method of the foamed lightweight high temperature resistant diatomite insulating brick according to claim 4, wherein the high temperature auxiliary material is one or more of kaolin, bauxite and aluminum slag with an alumina content of more than 30%.

6. The method for preparing the foamed lightweight high temperature resistant diatomite insulation brick as claimed in claim 4, wherein the quick setting enhancer is one or a mixture of calcium sulfate, calcium hydroxide, sodium silicate and silicon oxide.

7. The preparation method of the foamed lightweight high-temperature-resistant diatomite insulating brick as claimed in claim 1, wherein the foaming agent and the foam stabilizer are mixed according to a mass ratio of 1:1, the foaming agent is K12, and the foam stabilizer is sodium silicate.

8. The preparation method of the foamed lightweight high temperature resistant diatomite insulation brick as claimed in claim 7, characterized in that a water reducing agent is added into the mixed solution of the foaming agent and the stabilizing agent, and the water reducing agent is triisopropanolamine.

9. The preparation method of the foamed lightweight high temperature resistant diatomite insulating brick as claimed in claim 1, wherein the forming binder is one or two of high alumina cement and sulphoaluminate cement.

10. The preparation method of the foamed lightweight high temperature resistant diatomite insulation brick according to claim 1, wherein the diatomite mass content in the raw material of the insulation brick is 50-70%.

Technical Field

The invention relates to a preparation method of a foamed lightweight high-temperature-resistant diatomite insulating brick. The diatomite insulation brick has the innovative technical products of preparation upgrading innovation, application range expansion, energy conservation, high yield and value increment of the diatomite insulation brick.

Background

There is a great gap between the products of diatomite and foreign products such as western europe, usa and japan in comparison with quality, function and added value.

From the production technology of the diatomite insulating brick, the traditional process method of adding sawdust powder into pure diatomite, mixing with water, extruding and forming, drying in the shade to dewater by time weather, burning in a kiln for ten days, and finishing and forming is mainly adopted. Simple technology, backward process, large occupied area, long production process, low yield and poor comprehensive integration efficiency. The long-term single product is used for manufacturing the low-grade insulating brick, the traditional manual workshop type manufacturing management mode is kept, the scale is small, the production equipment is backward, the degree of professional automatic production equipment is low, the management and technical strength are seriously insufficient, and the innovation capability is lacked. Because the grade is low, the profit is little, and the economic benefit is not good all the time, the research and development investment of enterprises is relatively difficult, and the method is the root cause influencing the slow development of the industry.

Over forty years, scientific technology has been rapidly developed, higher requirements on diatomite attached products are met, and the quality and quantity of the diatomite insulating brick are higher. The insulating brick obtained by the traditional insulating brick preparation method at present has the advantages of few varieties, long time consumption, low strength and no environmental protection. Therefore, the research on the light high-temperature-resistant insulating brick with environmental protection and high strength is of great significance.

Disclosure of Invention

The invention provides a preparation method of a foamed lightweight high-temperature-resistant diatomite insulating brick, aiming at solving the problems of long time consumption, low strength and environmental pollution in the preparation process of the traditional insulating brick. The traditional annular kiln brick firing process is changed into an environment-friendly rotary kiln powder firing process, so that the time required for calcining the diatomite bricks in the original annular kiln is shortened to 350 hours (14 days) to 1 hour, the energy can be saved, and the pollution caused by the exhaust emission of the annular kiln is avoided. The low water formula process is adopted, so that the time for drying and dehydrating the original diatomite wet green bricks in the shade is 60-90 days, and the time for leaving the factory is shortened to 28 days at most. The super-strong light multifunctional heat-insulating brick with the temperature resistance of 1000-.

In order to achieve the purpose, the invention adopts the following technical scheme:

a preparation method of a foamed lightweight high-temperature-resistant diatomite insulating brick comprises the following steps:

1) adding a forming binder and water into the calcined and shaped diatomite to prepare a raw material of the insulating brick; the mass content of the diatomite in the raw materials of the insulating brick is 15-80%, preferably 50-70%; the mass content of the forming binder is 10-70%, and the forming binder is preferably one or two of high-alumina cement and sulphoaluminate cement; the mass content of water is 10-35%;

2) dissolving a foaming agent and a foam stabilizer in water, introducing compressed air, and stirring to form bubbles; adding air bubbles into the mixed raw materials of the insulating brick, and stirring to obtain the insulating brick with the volume density of 0.4-1.2g/cm²Fluid diatomite cement foam slurry;

3) and (3) injecting the flowing diatomite cement foam slurry into a brick making production line transmission mould, automatically condensing, curing and forming within 10-60min to obtain a wet green brick, and demoulding, dehydrating and drying the wet green brick to obtain the insulating brick.

In order to improve the strength and performance of the insulating brick, the insulating brick obtained in the step 3) is subjected to secondary high-temperature shaping, wherein the temperature of the secondary high-temperature shaping is 1000-1300 ℃, the shaping time is 30-60min, and cooling is carried out. The glass phase produced by diatoms at high temperature can be cooled to improve strength and dimensional stability and shape.

The invention combines the primary calcination and shaping process and the secondary high-temperature shaping process. The once calcining and setting process includes adding diatomite powder alone or compounded into rotary kiln for calcining. The one-time calcination shaping process specifically comprises the following steps: pulverizing into 100-mesh 400-mesh diatomite powder, feeding into a rotary kiln, adding biomass fuel, and calcining by using liquefied natural gas as a calcining heat source; the calcination temperature is controlled at 200-950 ℃, the calcination time is 30-60min, and the qualitative effect of removing organic impurities and high-temperature heat setting and preventing subsequent shrinkage deformation of the glass phase of the diatomite powder or the product at 900 ℃ is achieved. And wherein the combustion time in the temperature interval of 850-950 ℃ must be guaranteed to be not less than 20 min; and cooling and discharging after the calcination is finished.

Preferably, the step 1) further comprises the step of adding a high-temperature auxiliary material and a quick-setting reinforcing agent into the insulating brick raw material, wherein the high-temperature auxiliary material accounts for 10-70% of the insulating brick raw material by mass, and the quick-setting reinforcing agent accounts for 2-18% of the insulating brick raw material by mass. The high-temperature auxiliary material is one or more of kaolin, bauxite and aluminum slag with the content of aluminum oxide being more than 30%, and the quick-setting reinforcing agent is one or more of calcium sulfate, calcium hydroxide, sodium silicate and silicon oxide.

Preferably, the foaming agent and the foam stabilizer are mixed according to the mass ratio of 1:1, the foaming agent is K12, the foam stabilizer is sodium silicate, and the mass ratio of the foaming agent to the foam stabilizer to water is preferably 1:1 (5-15); preferably, a water reducing agent is added into a mixed solution of the foaming agent and the stabilizing agent, wherein the water reducing agent is triisopropanolamine, and accounts for 0.1-5% of the mass of the foaming agent and the foam stabilizing agent aqueous solution. The foam amount is set and controlled by the volume density of the insulating bricks with different designs, and the light bricks with different volume densities can be manufactured.

The diatomite thermal insulation brick obtained by the preparation method has the temperature resistance of 900-1250 ℃, and the brick density of 0.2-1.0g/cm²The strength is 0.4-3Mpa, the re-burning line change is less than 2%, and the heat conductivity coefficient is less than 0.20 w/M.k.

The invention has the beneficial effects that:

(1) compared with the traditional preparation method of diatomite crushing, sawdust adding, water adding and mixing, extrusion forming, air drying and dehydration, kiln burning and finishing and packaging, the invention adopts the preparation process of diatomite crushing, quick calcination and shaping, bonding auxiliary agent adding, foam molding, finishing and packaging and secondary shaping, and the original 336-hour annular kiln calcined brick is changed into rotary kiln diatomite powder calcination and shaping, so that the required time for original annular kiln calcination of the diatomite brick is shortened to 1 hour from 350 hours (14 days), thereby saving energy and avoiding the pollution caused by exhaust gas emission of the annular kiln.

(2) The process of the invention is a low water consumption process, shortens the time of about 60 days required by the green brick dehydration shade drying process to 28 days, saves the time by more than 30 days, and saves the whole green brick wind drying dehydration field and the annular kiln field (occupying more than half of the area of an enterprise).

(3) The invention is a continuous production process, is easy to establish into an automatic production line, improves the production efficiency by more than 50 percent, and improves the yield by 2 to 4 times in the same time; the flowing diatomite cement foam slurry with different densities can be obtained by controlling the amount of bubbles introduced into the raw materials of the insulating brick, and the light bricks with different volume densities are prepared.

(4) The heat-insulating brick prepared by the invention has the advantages of high strength, high temperature resistance up to 1000-plus-1200 ℃, shrinkage rate lower than 2%, high dimensional stability, heat conductivity lower than 0.20w/M.k and good heat-insulating property.

Detailed Description

Example 1

Uniformly mixing 350 g of the once-calcined and shaped diatomite ore fine powder and 350 g of high-alumina cement, adding 250 g of water, and stirring to form slurry to prepare a raw material of the insulating brick for later use; dissolving 4 g of foaming agent K12+4 g of foam stabilizer sodium silicate and 50 g of clear water into aqueous liquid, and beating water foams with the volume of two liters by using a high-speed stirrer; slowly adding the stirred water body foam into the diatomite cement slurry, stirring while adding, pouring into a mold with the volume of 1 liter when keeping the volume of foam powder slurry to be 1 liter, troweling, curing and demolding after 60 minutes, and drying and hardening. Bulk density 0.7g/cm³Strength > 12kg/cm²The shrinkage is less than 2 percent, and the heat conductivity coefficient is less than 0.20 w/M.k.

Example 2

250 g of diatomite ore fine powder and 250 g of high-alumina cement which are calcined and shaped at one time are uniformly mixed, 180 g of water is added and stirred into slurry, and the raw material of the insulating brick is prepared for standby; 4 g of foaming agent K12+4 g of foam stabilizer sodium silicate, 50 g of clear water and 2g of water reducer triisopropanolamine, wherein the foaming agent and the foam stabilizer are dissolved into water liquid, the water liquid is added into the water reducer, and water body foam with the volume of two liters is beaten by a high-speed stirrer; slowly adding the water foam into the stirred diatomite cement slurry, adding the foam while stirring, pouring into a mold with the volume of 1 liter when keeping the foam slurry to be 1 liter, troweling, curing and demolding after 50 minutes, and removing the water for hardening. Bulk density 0.5g/cm³Strength > 6kg/cm²The shrinkage is less than 2 percent, and the heat conductivity coefficient is less than 0.20 w/M.k.

Example 3

250 g of primary calcined and shaped diatomite ore fine powder, 150 g of kaolin powder, 100 g of high alumina cement, 100 g of sulphoaluminate cement and 100 g of calcium sulfate serving as a quick setting reinforcing agent are uniformly mixed together, and 220 g of water is added and stirred into slurry for later use; 4 g of foaming agent K12+4 g of foam stabilizer sodium silicate, 2g of water reducing agent and 50 g of clear water, wherein the foaming agent and the foam stabilizer are dissolved into water liquid firstly2 liters of water body foam is beaten out by a high-speed stirrer; slowly adding the stirred water body foam into the diatomite cement slurry, stirring while adding the foam, pouring into a mold with the volume of 1 liter when keeping the foam powder slurry to be 1 liter, troweling, curing within 40 minutes, demolding, drying, and hardening. Bulk density 0.7g/cm³Strength > 12kg/cm²The shrinkage is less than 2 percent, and the heat conductivity coefficient is less than 0.20 w/M.k.

Example 4

Primary calcining and shaping: delivering the diatomite powder crushed into 200 meshes into a rotary kiln, adding biomass fuel, and calcining by using liquefied natural gas as a calcining heat source; the calcination temperature is controlled at 250 ℃ and 950 ℃, and the total calcination time is 40 min; and wherein the combustion time within the temperature interval of 850 ℃ and 950 ℃ is 30 min; and cooling and discharging after the calcination is finished.

Uniformly mixing 340 g of primary calcined and shaped diatomite ore fine powder, 100 g of kaolin powder, 80 g of high-alumina cement, 80 g of sulphoaluminate cement and 100 g of calcium sulfate serving as a quick-setting reinforcing agent, adding 150 g of water, and stirring into slurry for later use;

4 g of foaming agent K12+4 g of foam stabilizer sodium silicate, 2g of water reducing agent and 50 g of clear water, dissolving the foaming agent and the foam stabilizer into water liquid, beating out water foam with the volume of 2 liters by using a high-speed stirrer, wherein the stirring speed is not lower than 1000 revolutions per minute, slowly adding the stirred water foam into diatomite cement slurry, adding the foam while stirring, pouring into a mold with the volume of 1 liter when keeping the volume of foam powder slurry to be 1 liter, leveling, curing and demolding within 30 minutes at normal temperature, and removing dry water for hardening; and finally, carrying out secondary high-temperature shaping at 1200 ℃ for 40min, and cooling. The volume density of the obtained insulating brick is 0.7g/cm³Strength > 15kg/cm²The shrinkage is less than 1.6 percent, and the heat conductivity coefficient is less than 0.20 w/M.k.