CN1557762A - Method for research and development of mullite heat-insulating fireproof materials using industrial sludge from aluminium section factory - Google Patents
Method for research and development of mullite heat-insulating fireproof materials using industrial sludge from aluminium section factory Download PDFInfo
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- CN1557762A CN1557762A CNA2004100161902A CN200410016190A CN1557762A CN 1557762 A CN1557762 A CN 1557762A CN A2004100161902 A CNA2004100161902 A CN A2004100161902A CN 200410016190 A CN200410016190 A CN 200410016190A CN 1557762 A CN1557762 A CN 1557762A
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
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Abstract
The present invention is the process of producing light heat insulating mullite refractory material with industrial sludge from aluminum section factory as main material, and belongs to the field of comprehensive solid waste utilizing technology and ecological environment material technology. The production process includes following steps: depositing waste liquid from aluminum section factory to obtain solid waste slag; mixing the solid waste slag with inflammable matter or foaming agent, forming, stoving and sintering at 1350-1450 deg.c for 1-6 hr to obtain light heat insulating refractory material with main crystal phase of mullite. The present invention has excellent performance and low cost.
Description
Technical field
The present invention relates to utilize the method for waste aluminum sludge development light-weight mullite thermal insulation fire-resistant material, it is to be the comprehensive utilization that main raw material development light-weight mullite thermal insulation fire-resistant material belongs to solid waste with the waste aluminum sludge, belongs to the ecological environment material nd technical field.
Technical background
Waste aluminum sludge is that the aluminium shape surface process produces a large amount of waste liquids, and it is milky colloidal solution, the ultra-fine and high dispersing of particle.This waste liquid is in case discharge inevitable serious environment pollution and river waters, destruction ecology.Therefore before the discharging of waste liquid, a large amount of mud that treating processes must be produced are removed.Factory adopts precipitation and filter method, filters solid mud, remaining clarifying filtrate discharge.This solid mud main component is γ-AlOOH, Al (OH)
3With solid matter with amorphous body structure.Sludge moisture content is up to 70-80%, and this amount of sludge is very big, and a large aluminum profile factory can produce 25-30 ton mud every day, the 800-900 ton is arranged, annual recyclable more than 10,000 tons in every month.There are tens families in domestic large aluminum profile enterprise, and there is family more than 100 in medium and small sized enterprises, and annual to produce industrial sludge quantity very big.Have a strong impact on the comprehensive regulation and the ordinary production of aluminium section bar plant waste liquid, seriously cause the secondary pollution of aluminium section bar plant.Therefore the comprehensive utilization of mud is essential, has important environment protection significance.The present invention utilizes aluminium section bar industrial sludge and clay to be main raw material, with flammable admixture method and foaming process, and development light-weight mullite thermal insulation fire-resistant material.Light-weight mullite thermal insulation fire-resistant material has excellent high-temperature thermal property and mechanical property.It is the important heat-insulation and heat-preservation material of thermal kiln furnace.Because anti-rapid heat cycle performance and good heat insulating make it well received in thermal kiln furnace is built.Because it is main raw material that industrial sludge is adopted in this invention, raw materials cost is very low, economic benefit and social benefit highly significant.
By retrieval as can be known: Chinese patent publication number 1051541 relate to employing with aluminium section bar processing waste residue directly with the operational path of hydrochloric acid reaction, decolouring by charcoal absorption obtains water white liquid polymeric aluminum oxide; Chinese patent publication number 1350065 relates to the sulfur waste acid that produces with waste Aluminum slag and aluminium shape surface chemical treatment, useless sodium hydroxide is raw material, preparation Tai-Ace S 150, sodium aluminate and aluminium hydroxide; Light reel number: 1993GC14 relates to and utilizes Al (OH)
3Gel waste residue is produced polymer alumina; Light reel number: 2000GC26 relates to the research that utilizes aluminum dross to produce water conditioner one Tai-Ace S 150; Light reel number: 1995GC23 relates to and utilizes the alumilite process aluminum dross to produce Tai-Ace S 150.Therefore, Shang Weiyou utilizes waste aluminum sludge to prepare the report of mullite thermal insulation fire-resistant material method, can set up technology and technology that the aluminium section bar industrial sludge with autonomous property right is developed light-weight mullite thermal insulation fire-resistant material.
Summary of the invention
The objective of the invention is to invent a kind of method of utilizing waste aluminum sludge development light-weight mullite thermal insulation fire-resistant material.
The present invention is achieved in that this production stage is: (1) is main raw material with waste aluminum sludge, this mud is that the aluminium shape surface treating processes produces a large amount of waste liquids, through the solid slag that sedimentation and filtration obtains, this mud main component is γ-AlOOH, Al (OH)
3With the solid matter with amorphous body structure, fat clay content is 10-80% in the material that prepare, and dewatered sludge content is 20-90%, requires bonding clay plasticity-good, refractoriness height, R
2O content is low; (2) flammable admixture or foaming agent development light-weight mullite thermal insulation fire-resistant material are mixed in employing, dewatered sludge, plastic clay and flammable admixture or foaming agent mix, add the water batch mixing, carry out plastic molding, base substrate drying, base substrate are through sintering, and sintering temperature is 1350-1450 ℃, soaking time is 1-6 hour, and obtaining with the mullite is the lightweight refractory of principal crystalline phase; (3) mullite content is 50-95% in the product of producing, and volume density is 0.6-1.0g/cm
3, anti-to tear intensity open be 0.7-3Mpa, refractoriness 〉=1600 ℃.
The present invention compared with prior art has following novelty and advantage:
1) raw material and technological innovation: it is main raw material that prior art adopts commercial alumina, and this project employing waste aluminum sludge is a raw material, innovation with raw material and technology belongs to the comprehensive utilization of solid waste and the project that turns waste into wealth, and therefore has great environment protection significance.
2) the present invention compared with prior art, the industrial sludge that this project adopts has that particle is ultra-fine, surface-area is big, active high characteristics help solid state reaction and sintering, help forming the mullite crystalline phase, reduce firing temperature, save energy.
3) product performance of the present invention are better than the performance of prior art, and product density is little, the folding strength height, and good heat insulating, thermally-stabilised good, long service life.
4) compared with prior art raw materials cost is very low in the present invention, and economic benefit and social benefit be very remarkable to have the very strong market competitiveness.
The present invention relates to a kind of light-weight mullite thermal insulation fire-resistant preparation methods, it is main raw material with the waste aluminum sludge, adopts and mixes flammable admixture method and foaming process development light-weight mullite thermal insulation fire-resistant material.With aluminium section bar industrial sludge dewatered drying, obtain dewatered sludge through 1200-1350 ℃ of light-burned formation mud grog.Mud grog, clay and expanded plastic ball (whipping agent) mix, and add the water pugging then, form the plasticity-walk.Walk becomes the base substrate of different specification size in die for molding.After the base substrate drying, place High Temperature Furnaces Heating Apparatus 1350-1450 ℃ sintering, be incubated after 1-6 hour, naturally cool to room temperature.
Embodiment
With aluminium section bar industrial sludge dewatered drying, obtain dewatered sludge, its composition: SiO
22-3%, Al
2O
3Be 60-65%, loss on ignition is 33-35%, and other impurity are 0.8-1.2%.With dewatered sludge through 1200-1350 ℃ of light-burned formation mud grog, α-Al in the grog
2O
3Content be 90-98%.Grog is broken and grind to form the 200-320 sieve mesh, as one of main raw material.Raw clay must be drawn and wash, and removes sand grains, increases raw material plasticity-.
The prescription of material: light-burned mud grog 20-90%, clay 10-80% adds expanded plastic ball 1.5-3%.Light-burned mud grog, clay and expanded plastic ball mix, and add the water pugging then, form the plasticity-walk.The plasticity walk is molded into the base substrate of different specification size in punching block or wooden model.Base substrate moves into the baking room oven dry behind one day airing, bake out temperature is 100 ℃, and controlling moisture content is 5-6%.
The dry body body places rib formula kiln (other kilns) to burn till, and sintering temperature is 1350-1450 ℃.Heat-up rate: room temperature → 500 ℃ are 100 ℃/hour; 500 ℃ of insulations 1 hour, allow the perfect combustion of expanded plastic ball; 500 → 600 ℃ is 50 ℃/hour; 600 → 1200 ℃ is 150 ℃/hour; 1350-1450 ℃ of insulation 1-6 hour, naturally cool to room temperature then.
Utilize step 2 employing of the method for waste aluminum sludge development light-weight mullite thermal insulation fire-resistant material to mix flammable admixture or foaming agent development light-weight mullite thermal insulation fire-resistant material, add the water batch mixing, carry out plastic molding, the base substrate drying, base substrate is 1350-1450 ℃ through sintering temperature, soaking time is 1-6 hour, and obtaining with the mullite is the lightweight refractory of principal crystalline phase; The flammable admixture of its narration is expanded plastic ball, sawdust, rice husk, coke powder or reclaims useless poly-stupid vinyl plastics.Foaming agent is that sodium abietate prepares foaming agent, and the flammable admixture of narration adds the expanded plastic ball in the dewatered sludge through grinding to form fine powder, and particle diameter is 1-3mm, and addition is 1.2-3.0%.
Embodiment 1:
1) development light-weight mullite thermal insulation fire-resistant material main raw material is that water content is 70-80% with the industrial sludge of Nan Ping, Fujian Province Chinalco, and the drying dehydration is dewatered sludge, its chemical constitution: SiO
2Be 2.34%, Al
2O
3Be 61.16%, Fe
2O
3Be 0.27%, CaO is 0.48%, and MgO is 0.37%, K
2O is 0.03%, Na
2O is 0.34%, and IL is 34.26%.Clay is formed: SiO
2Be 72.06%, Al
2O
3Be 18.56%, Fe
2O
3Be 1.05%, TiO
2Be 0.09%, CaO is 0.07%, and MgO is 0.21%, K
2O is 0.85%, Na
2O is 0.09%, and IL is 7.01%.Expanded plastic spherolite degree is 1-3mm.
2) dewatered sludge with the fragmentation of mud grog, grinds to form 200-320 order powder through 1300 ℃ of light-burned formation mud grogs.Clay places the pond to draw and washes, flush away sand grains and other impurity, and oven dry breaks into powder.Selecting expanded plastic spherolite degree is 1-3mm.
3) light-burned mud grog 60%, clay 40% adds expanded plastic ball 1.6-2.4% and mixes, and adds water batch mixing pugging 30 minutes then, forms the plasticity-walk.The plasticity walk is molded into the base substrate of different specification size in punching block.Base substrate moves into the baking room oven dry behind one day airing, bake out temperature is 100 ℃, and controlling moisture content is 5-6%.The dry body body places rib formula kiln to burn till, and sintering temperature is 1380 ℃.Heat-up rate: room temperature → 500 ℃ are 100 ℃/hour; 500 ℃ of insulations 1 hour, allow the perfect combustion of expanded plastic ball; 500 ℃ → 600 ℃ is 50 ℃/hour; 600 ℃ → 1200 ℃ is 150 ℃/hour; 1380 ℃ of insulations 2 hours, naturally cool to room temperature then.Carry out the experimental study of differing temps and different soaking times simultaneously.Each sample is carried out performance and structural analysis, analytical results: density is 0.72-9.2g/cm
3, folding strength is 1.10-1.60Mpa.
4) development prescription and performance
The prescription of table 1 embodiment 1 and processing condition and performance (the batch mixing pugging time is 30 minutes)
The anti-intensity of analysing of sample mud grog clay expanded plastic ball sintering temperature soaking time density
(wt%) (wt%) (wt%) (℃) (hour) (g/m
3) (Mpa)
Sample 1 60 40 1.6 1,380 2 0.92 1.25
Sample 2 60 40 1.8 1,380 2 0.82 1.50
Sample 3 60 40 2.0 1,380 2 0.81 1.60
Sample 4 60 40 2.2 1,380 2 0.78 1.46
Sample 5 60 40 2.4 1,380 2 0.72 1.10
Principal crystalline phase is a mullite in embodiment 1 sample, and paracrystalline phase is a corundum etc.
Embodiment 2:
The 2 batch mixing pugging times of present embodiment are 15 minutes, and other preparation technologies are identical with embodiment 1, inquire into different sintering temperatures to effect of material performance.
The prescription of table 1 embodiment 2 and processing condition and performance (the batch mixing pugging time is 15 minutes)
The anti-intensity of analysing of sample mud grog clay expanded plastic ball sintering temperature soaking time density
(wt%) (wt%) (wt%) (℃) (hour) (g/cm
3) (Mpa)
Sample 1 60 40 2.0 1,340 2 0.695 0.86
Sample 2 60 40 2.0 1,360 2 0.735 1.40
Sample 3 60 40 2.0 1,380 2 0.710 1.49
Sample 4 60 40 2.0 1,400 2 0.680 1.70
Sample 5 60 40 2.0 1,420 2 0.695 1.80
Principal crystalline phase is a mullite in embodiment 2 samples, and paracrystalline phase is a corundum etc.The batch mixing pugging time shortens, and the density of material reduces, and sintering temperature raises, and the anti-intensity of analysing of material increases.
Embodiment 3:
It is 15 minutes that present embodiment 3 batch mixings are practiced the dirty time, and other preparation technologies are identical with embodiment 1, inquire into the different sintered heat insulating times to effect of material performance.
The prescription of table 1 embodiment 3 and processing condition and performance (the batch mixing pugging time is 15 minutes)
The anti-intensity of analysing of sample mud grog clay expanded plastic ball sintering temperature soaking time density
(wt%) (wt%) (wt%) (℃) (hour) (g/cm
3) (Mpa)
Sample 11 60 40 2.0 1,380 1 0.727 1.60
Sample 12 60 40 2.0 1,380 2 0.714 1.90
Sample 13 60 40 2.0 1,380 3 0.712 2.00
Sample 14 60 40 2.0 1,380 4 0.705 1.70
Sample 15 60 40 2.0 1,380 5 0.697 0.95
Principal crystalline phase is a mullite in embodiment 3 samples, and paracrystalline phase is a corundum etc.The sintering temperature soaking time increases, and density of material reduces; Soaking time 1 → 3 hour, folding strength are to increase, soaking time 3 → 5 hours, and folding strength reduces.
Claims (4)
1. utilize the method for waste aluminum sludge development light-weight mullite thermal insulation fire-resistant material, it is characterized in that:
This production stage is:
(1) be main raw material with waste aluminum sludge, this mud is that the aluminium shape surface treating processes produces a large amount of waste liquids, and through the solid slag that sedimentation and filtration obtains, this mud main component is γ-AlOOH, Al (OH)
3With the solid matter with amorphous body structure, fat clay content is 10-80% in the material that prepare, and dewatered sludge content is 20-90%, requires bonding clay plasticity-good, refractoriness height, R
2O content is low;
(2) flammable admixture or foaming agent development light-weight mullite thermal insulation fire-resistant material are mixed in employing, dewatered sludge, plastic clay and flammable admixture or foaming agent mix, add the water batch mixing, carry out plastic molding, base substrate drying, base substrate are through sintering, and sintering temperature is 1350-1450 ℃, soaking time is 1-6 hour, and obtaining with the mullite is the lightweight refractory of principal crystalline phase;
(3) mullite content is 50-95% in the product of producing, and volume density is 0.6-1.0g/cm
3, anti-to tear intensity open be 0.7-3Mpa, refractoriness 〉=1600 ℃.
2. according to the method for the described waste aluminum sludge development of claim 1 light-weight mullite thermal insulation fire-resistant material, it is characterized in that: the flammable admixture of step 2 narration is expanded plastic ball, sawdust, rice husk, coke powder or reclaims useless poly-stupid vinyl plastics.
3. according to the method for the described waste aluminum sludge development of claim 1 light-weight mullite thermal insulation fire-resistant material, it is characterized in that: the foaming agent of step 2 narration is that sodium abietate prepares foaming agent.
4. develop the method for light-weight mullite thermal insulation fire-resistant material according to the described waste aluminum sludge of claim 2, it is characterized in that: the flammable admixture of step 2 narration is in the dewatered sludge through grinding to form fine powder, add expanded plastic or useless poly-stupid vinyl plastics, plastics are spherical or irregular granular, particle diameter is 1-3mm, and addition is 1.2-3.0%.
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|---|---|---|---|
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|---|---|---|---|
| CNB2004100161902A CN1293011C (en) | 2004-02-10 | 2004-02-10 | Method for research and development of mullite heat-insulating fireproof materials using industrial sludge from aluminium section factory |
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| CN1293011C CN1293011C (en) | 2007-01-03 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105817463A (en) * | 2016-03-25 | 2016-08-03 | 无锡宇辰工业污泥处理技术研究院有限公司 | Resourceful treatment method for crystalline silicon cutting waste mortar and aluminum oxidation sludge |
| CN106083097A (en) * | 2016-06-28 | 2016-11-09 | 昆明理工大学 | A kind of preparation method of fly ash base mullite fire resistant insulation material |
| CN106747612A (en) * | 2017-02-14 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the alum sludge base porous ceramic grain of the paper powder that adulterates |
| CN106747613A (en) * | 2017-02-14 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the footwear material PU powder waterworks sludge base porous ceramic grains that adulterate |
| CN106747614A (en) * | 2017-02-14 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the waterworks sludge base porous ceramic grain of the scrap rubber powder that adulterates |
| CN106747611A (en) * | 2017-02-14 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the alum sludge base porous ceramic grain of the kitchen garbage that adulterates |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1187280C (en) * | 2003-04-28 | 2005-02-02 | 福州大学 | Method of making mullite refractory using industrial sludge from aluminium section plant |
| CN1202040C (en) * | 2003-04-28 | 2005-05-18 | 福州大学 | Method of making jolite and mullite refractory using industrial sludge from aluminium section plant |
-
2004
- 2004-02-10 CN CNB2004100161902A patent/CN1293011C/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105817463A (en) * | 2016-03-25 | 2016-08-03 | 无锡宇辰工业污泥处理技术研究院有限公司 | Resourceful treatment method for crystalline silicon cutting waste mortar and aluminum oxidation sludge |
| CN106083097A (en) * | 2016-06-28 | 2016-11-09 | 昆明理工大学 | A kind of preparation method of fly ash base mullite fire resistant insulation material |
| CN106747612A (en) * | 2017-02-14 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the alum sludge base porous ceramic grain of the paper powder that adulterates |
| CN106747613A (en) * | 2017-02-14 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the footwear material PU powder waterworks sludge base porous ceramic grains that adulterate |
| CN106747614A (en) * | 2017-02-14 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the waterworks sludge base porous ceramic grain of the scrap rubber powder that adulterates |
| CN106747611A (en) * | 2017-02-14 | 2017-05-31 | 福建师范大学 | A kind of preparation method of the alum sludge base porous ceramic grain of the kitchen garbage that adulterates |
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| CN1293011C (en) | 2007-01-03 |
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