CN1151992C - Method for preparing spheric closed pore expanded perlite, and products thereby - Google Patents
Method for preparing spheric closed pore expanded perlite, and products thereby Download PDFInfo
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- CN1151992C CN1151992C CNB991163567A CN99116356A CN1151992C CN 1151992 C CN1151992 C CN 1151992C CN B991163567 A CNB991163567 A CN B991163567A CN 99116356 A CN99116356 A CN 99116356A CN 1151992 C CN1151992 C CN 1151992C
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- perlite
- temperature
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- closed pore
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B14/02—Granular materials, e.g. microballoons
- C04B14/04—Silica-rich materials; Silicates
- C04B14/14—Minerals of vulcanic origin
- C04B14/18—Perlite
- C04B14/185—Perlite expanded
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
- C04B20/02—Treatment
- C04B20/04—Heat treatment
- C04B20/06—Expanding clay, perlite, vermiculite or like granular materials
- C04B20/068—Selection of ingredients added before or during the thermal treatment, e.g. expansion promoting agents or particle-coating materials
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- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Civil Engineering (AREA)
- Silicates, Zeolites, And Molecular Sieves (AREA)
Abstract
The present invention discloses a method for preparing a spheric pore closed expanded perlite. In the method, materials are pulverized, sieved into materials of which the fineness is from 40 to 325 meshes; the sieved materials are mixed and stirred; silica-rich materials and/or metal oxide of which the weight proportion is 20 to 100 % of that of micropowder of the materials is added; the micropowder is preheated; the temperature is controlled at from 400 DEG C to 700 DEG C; the micropowder is expanded; the perlite micropowder is expanded in an expansion furnace at a plurality of temperature zones at the temperature from 800 to 1300 DEG C for 5 to 20 seconds; and then the perlite miropowder is discharged from the furnace. The particle surfaces after being expanded are in continuous and smooth spheroids, the ball-shaped rate can reach 80%, the particles are not easy to crush, the closed porosity of the product can reach 95%, and the water absorption rate is reduced to 38 %.
Description
The present invention relates to a kind of manufacture method of lightweight insulation product, relate in particular to a kind of manufacture method of spherical expanded perlite with closed pore.
Expanded perlite product always, basic production technology is that ore is through pulverizing, screening, preheating, expansion, its expansion temperature is 1400 ℃, sieve size is the 20-40 order, this vesicular structure product has irregular profile, the surface has no successive such as many holes seam, crackle, convex-concave surface outer shape, and inside also is pore character.Because its porous and water absorption character, they are in soil improvement, sorbing material, show unique function in the application in fields such as aids,filter, in application, though himself have the excellent insulating heat-insulating property as building insulation lagging material or matrix material, but because density stabilized poor performance, not durable, frangible too big with water-intake rate, tend to cause the serious decline in quality product and life-span; Produce the opening structural reason of this porous or pore be to produce in material generally on the low side in the removal amount of pre-heating stage adhesive water, or, often cause residual amount, particularly adhere to hypervolia because the ore in sand form of preheating temperature, warm up time and different moisture content mates improperly; In this case, high-temperature roasting, moisture that ore in sand form moment in expansion furnace is subjected to about 1400 ℃ are sharply broken through particle surface and are evaporated, thereby forming porous pipeline slit and be full of cracks with regard to irregular material surface and inside originally, formed the expanded perlite product of vesicular structure thus, test shows, this product immersion is after 120-150 minute, water-intake rate can reach 300-800%, mirror is observed the no successive of its material surface down, concavo-concave, the corner angle part is more, is the shape of irregular.This feature also is to cause the not good major reason of frangible, the density stabilized performance of product simultaneously.
In order to overcome the perlitic above-mentioned defective of traditional vesicular structure, people have carried out all effort, and interpolation hydrophober is a kind of method wherein, still, carry out hydrophobic on irregular surface and handle just makeshift.In other words, the rete that forms at the hole oral area behind the hydrophobic can be along with particle during puddling processing
SelfBroken and ineffective, in fact remain high water absorbing capacity, and cost increases thereupon also; The way that someone has adopted cement to apply is stitched with the hole of sealing porous surface, and the result is ideal very, and the one, output is not high, and the 2nd, capacity increases; In recent years, Japanese kokai publication hei 9-183612 has announced a kind of manufacture method of spherical pearlstone, it is to utilize the common roasting in stove of a kind of high-melting-point micro mist and perlite, though this method helps the formation of spherical product, has but increased unit weight and cost.
The purpose of this invention is to provide a kind ofly produce that density stabilized performance is good, water-intake rate is low, mortar is mobile good and reduce the manufacture method of the spherical closed-cell expanded perlite of environmental pollution.
Technical scheme of the present invention realizes in the following manner:
A kind of manufacture method of spherical expanded perlite with closed pore comprises the following steps:
(1) pulverizes, will pulverize with pulverizer after material-glassy rock drying;
(2) screening, glassy rock is after crushed sieved, and isolates 40-325 purpose perlite powder;
(3) puddle, in perlite powder, mix the 20-100% silica-rich material and/or the metal oxide dielectric of its weight;
(4) preheating is carried out preheating with the mixture of perlite powder and dielectric material in preheating oven, preheating temperature is controlled at 400-700 ℃, perlite powder water content≤2% after the preheating;
(5) expand, allow the perlite powder that mixes dielectric material enter in the expansion furnace in plurality of temperature district, its cold zone is controlled to be 〉=800 ℃, and the high-temperature zone is controlled to be≤and 1300 ℃, the expansion time dimension is held in 5-20 and comes out of the stove after second;
(6) separate, pearlstone with mix medium and separate.
The glassy rock grinding particle size is preferably the 60-200 order.
Metal oxide is that manganese oxide, aluminum oxide, chromic oxide, silica-rich material are quartz sand, and its granularity is less than the perlite powder granularity.
Be controlled at warm up time 10-40 minute.
Rock preferably carries out drying treatment before pulverizing.
The effect of technology of the present invention and product is:
Particle surface after the expansion is the spherule of continuously smooth, spherical rate reaches 80%, be difficult for fragmentation, product rate of closed hole height can reach 95%, water-intake rate is low, reduce to 38%, the raw material availability height can utilize the following micro mist as waste material of traditional technology 60 orders, the mortar flowing property strengthens, and has reduced the pollution to environment.
The present invention mixed siliceous abundant material or metal oxide etc. with perlite powder before preheating mutually, in the time of pre-heating stage perlite thermal dehydration, also can be subjected to the processing of above-mentioned materials, rough and uneven in surface place is by further " reduction ", through 10-35 minute pre-hot-work, perlite particle further was spherule.
Expansion temperature and expansion effect depend on factors such as the kind, granularity, preheating condition of mineral products, and for the ore in sand form that natural moisture content is 4-6% (weight), residual amount is controlled at below 2%, and expansion temperature is generally 800-1300 ℃.Because of place of production mineralogical chemistry composition difference, water ratio is different, or even the former mineral products of the different ore deposit points in same orefield, its expansion temperature all has marked difference, expansion rate is also had nothing in common with each other, can fully expand under the temperature about 900 ℃ as some ore in sand form, some then also is difficult to reach ideal and expands or foaming effect under 1300 ℃.But various perlite mineral products all can expand under the temperature of the scope of the invention after having controlled remaining moisture content.
The granularity of ore in sand form and expansion temperature have direct relation, in general, the ore in sand form expansion temperature that granularity is bigger is higher, as the 20-40 order, granularity is that the following then expansion temperature of 60 orders distributes lower, even can be at temperature expansion below 1100 ℃, best ore in sand form granularity is the 60-200 order in the technology of the present invention.
In the forming process of closed pores infrastructure product; precise dose control is the factor of most critical with the control of expansion time; the present invention utilizes several different flat-temperature zones; material is progressive to be heated; and be heated evenly, residual moisture in the ore in sand form discharges also can be slow relatively, controls when proper when the residence time in the stove; material can not produce and anxious poly-burst phenomenon, thus formed have complete vitreous shell, the inner basic hollow unicellular structure that is.In the technology of the present invention, going into the residence time of stove ore in sand form in stove is 5-20 second,
Temperature variationScope is 800-1300 ℃, and the closed pore ratio defective product of formation can reach more than 90%, examines under a microscope, and expanded granular has continuous, level and smooth surface, and most of is spherical substantially, and through the test of water flotation process, rate of expansion reaches more than 95%.
In the technology of the present invention, the purpose that adds silica-rich material or metal oxide dielectric material is to improve the sphericity and the wall shell intensity of expansion product.Going into the stove material is subjected in the thermal process progressive; perlite particle is able to uniformly softening under the encirclement of fine media material; the wall shell does not occur rough and uneven in surface because of softening inequality; thereby make a material keep the shape facility of circle, simultaneously, the wall shell of vitreous under the heat protective effect of dielectric material constantly thickens; thereby improved the intensity of expanded granular relatively; after material was come out of the stove, dielectric material separated with the product that expand, but and overlapping investment use.
The invention will be further described below in conjunction with drawings and Examples:
Fig. 1 is technological process of production figure of the present invention.
Fig. 2 is the stereoscan photograph (amplifying 340 times) of embodiment 1 sample.
Fig. 3 is the stereoscan photograph (amplifying 100 times) of embodiment 2 samples.
Fig. 4 is the stereoscan photograph (amplifying 240 times) of comparative example 1 sample.
Fig. 5 is the stereoscan photograph (amplifying 900 times) of comparative example 2 samples.
As seen from Figure 1, technical process of the present invention is ore drying, pulverizing, sieve, puddle, preheating, to carry out through the feeder charging, in the electric expansion stove that gradient-heated expands, loading head gathers materials, product separates with dielectric material be finished product, in puddling, add dielectric material, bubbling air in the gradient-heated.
Embodiment 1: the crude pearlite drying and crushing is sieved choose 80-200 purpose pellet, mix the silicon ash and the alumina mixture of perlite weight 20%, preheating temperature is controlled to be 400 ℃, preheating made the residual amount of ore in sand form be controlled at below 2% in 35 minutes, the mixture of perlite and dielectric material enters in the electric expansion stove then, the cold zone temperature is 850 ℃ in the stove, and the high-temperature zone temperature is 1300 ℃, mixture by
Cold zone is to highThe warm area time was controlled at for 5 seconds, and the product of coming out of the stove makes dielectric material separate and test with expansible perlite particle with vibratory screening apparatus.Test-results is listed in table 1.Microscopically is observed spherical particle and is accounted for 80% at least.Particle has the surface of continuously smooth, imporosity crackle or tangible convex-concave portion, and constitutional features is seen Fig. 2.
Embodiment 2: with the crude pearlite drying and crushing, sieve and get 40-325 purpose pellet, the concrete operations step is with embodiment 1, mix the silicon ash and the chromic oxide mixture of perlite weight 60%, the preheating controlled temperature is 500 ℃, preheating made the residual amount of ore in sand form be controlled at below 2% in 25 minutes, the mixture of perlite and dielectric material enters in the electric expansion stove then, the cold zone temperature is 800 ℃ in the stove, the high-temperature zone temperature is 1200 ℃, mixture was controlled at for 10 seconds by cold zone to the high-temperature zone time, and the product of coming out of the stove makes dielectric material separate and test with expansible perlite particle with vibratory screening apparatus.Performance data after the products obtained therefrom test is listed in table 1, and constitutional features is seen Fig. 3.
Embodiment 3: with the crude pearlite drying and crushing, sieve and get 40-325 purpose pellet, the concrete operations step is with embodiment 1, mix the silicon ash and the chromic oxide mixture of perlite weight 80%, the preheating controlled temperature is 500 ℃, keeping the residual amount that made ore in sand form in 15 minutes is controlled at below 2%, the mixture of perlite and dielectric material enters in the electric expansion stove then, the cold zone temperature is 800 ℃ in the stove, the high-temperature zone temperature is 1150 ℃, mixture was controlled at for 15 seconds by cold zone to the high-temperature zone time, and the product of coming out of the stove makes dielectric material separate and test with expansible perlite particle with vibratory screening apparatus.
Embodiment 4: with the crude pearlite drying and crushing, sieve and get 60-200 purpose pellet, the concrete operations step is with embodiment 1, mix the silicon ash and the manganese oxide mixture of perlite weight 90%, the preheating controlled temperature is 600 ℃, keeping the residual amount that made ore in sand form in 20 minutes is controlled at below 2%, the mixture of perlite and dielectric material enters in the electric expansion stove then, the cold zone temperature is 800 ℃ in the stove, the high-temperature zone temperature is 1150 ℃, mixture was controlled at for 20 seconds by cold zone to the high-temperature zone time, and the product of coming out of the stove makes dielectric material separate and test with expansible perlite particle with vibratory screening apparatus.
Embodiment 5: with the crude pearlite drying and crushing, sieve and get 40-325 purpose pellet, the concrete operations step is with embodiment 1, mix the silicon ash and the chromic oxide mixture of perlite weight 100%, giving the thermal control temperature is 400 ℃, keeping the residual amount that made ore in sand form in 40 minutes is controlled at below 2%, the mixture of perlite and dielectric material enters in the electric expansion stove then, the cold zone temperature is 800 ℃ in the stove, the high-temperature zone temperature is 1100 ℃, mixture was controlled at for 15 seconds by the low temperature difference high-temperature zone time, and the product of coming out of the stove makes dielectric material separate and test with expansible perlite particle with vibratory screening apparatus.
Embodiment 6: with the crude pearlite drying and crushing, sieve and get 40-325 purpose pellet, the concrete operations step is with embodiment 1, mix the silicon ash and the alumina mixture of perlite weight 50%, giving the thermal control temperature is 700 ℃, keeping the residual amount that made ore in sand form in 10 minutes is controlled at below 2%, the mixture of perlite and dielectric material enters in the electric expansion stove then, the cold zone temperature is 800 ℃ in the stove, the high-temperature zone temperature is 1300 ℃, mixture was controlled at for 5 seconds by cold zone to the high-temperature zone time, and the product of coming out of the stove makes dielectric material separate and test with expansible perlite particle with vibratory screening apparatus.
Comparative example 1 is ground into 40-60 purpose pellet to the crude pearlite powder, not preheating, also do not do the surface and handle to send into to make in the electric expansion stove and stand 1100-1300 ℃ high temperature, and in stove, be detained for 10 seconds, test after coming out of the stove, the results are shown in table 1, structure is seen Fig. 4, table 1 data presentation, the spherical rate of this product, rate of closed hole is starkly lower than example 1 and example 2, and water-intake rate has increased more than 1 times.
Comparative example 2: get commercially available traditional porous pearlstone and carry out spherical rate, rate of closed hole and water-intake rate test, the results are shown in table 1, microstructure is seen Fig. 5.As can be seen from Table 1, the perlitic unit weight of conventional expanded is lower, but water-intake rate is 4-5 times of product of the present invention, and density stabilized property is not good, through test, its mortar poor mobile performance.
Table 1 spherical expanded perlite with closed pore and traditional porous expansion perlite performance comparison
| The performance sample | Ore in sand form granularity (moon) | Sample unit weight (kg/m 3) | Thermal conductivity (w/mk) | Spheroidization rate (%) | Rate of closed hole (%) | Water-intake rate (%) | The mortar flowing property |
| Embodiment 1 | 80-200 | 112 | 0.041 | 90 | 95 | 38 | Good |
| Embodiment 2 | 40-325 | 140 | 0.046 | 80 | 92 | 57 | Good |
| Embodiment 3 | 40-325 | 180 | 0.050 | 80 | 90 | 86 | Good |
| Embodiment 4 | 60-200 | 135 | 0.041 | 85 | 90 | 80 | Good |
| Embodiment 5 | 40-325 | 160 | 0.045 | 90 | 90 | 83 | Good |
| Embodiment 6 | 40-325 | 180 | 0.042 | 90 | 80 | 137 | Better |
| Comparative example 1 | 40-60 | 100 | 0.048 | ＜20 | 35 | 320 | Difference |
| Comparative example 2 | 20-40 | 80 | 0.051 | 0 | 0 | 460 | Difference |
* the test result behind 120 minutes vacuum filtration surface-moistures of 1 immersion
Claims (4)
1, a kind of manufacture method of spherical expanded perlite with closed pore comprises the following steps:
(1) pulverizes, will pulverize with pulverizer after material-glassy rock drying;
(2) screening, glassy rock is after crushed sieved, and isolates 40-325 purpose perlite powder;
(3) puddle, mix the 20-100% quartz sand and/or the metal oxide of its weight in perlite powder, described metal oxide is: manganese oxide, aluminum oxide, chromic oxide; Quartz sand, manganese oxide, aluminum oxide, chromic oxide granularity are less than the perlite powder granularity;
(4) give heat, the mixture of perlite powder and dielectric material is carried out preheating in giving hot stove, preheating temperature is controlled at 400-700 ℃, perlite powder water content≤2% after the preheating;
(5) expand, allow the perlite powder that mixes dielectric material enter in the expansion furnace in plurality of temperature district, its cold zone is controlled to be 〉=800 ℃, and the high-temperature zone is controlled to be≤and 1300 ℃, the expansion time dimension is held in 5-20 and comes out of the stove after second;
(6) separate, pearlstone with mix medium and separate.
2, the manufacture method of spherical expanded perlite with closed pore according to claim 1 is characterized in that: the glassy rock grinding particle size is the 60-200 order.
3, the manufacture method of spherical expanded perlite with closed pore according to claim 2 is characterized in that: be controlled at warm up time 10-40 minute.
4, the manufacture method of spherical expanded perlite with closed pore according to claim 2 is characterized in that: rock carries out drying treatment before pulverizing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB991163567A CN1151992C (en) | 1999-02-10 | 1999-02-10 | Method for preparing spheric closed pore expanded perlite, and products thereby |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB991163567A CN1151992C (en) | 1999-02-10 | 1999-02-10 | Method for preparing spheric closed pore expanded perlite, and products thereby |
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| CN1232004A CN1232004A (en) | 1999-10-20 |
| CN1151992C true CN1151992C (en) | 2004-06-02 |
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Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN1970484B (en) * | 2006-12-11 | 2010-08-18 | 四川嘉华企业（集团）股份有限公司 | Swelled perlite and its preparation method, its uses as modified microbead in producing high intensity low density oil well cement |
| US7381261B1 (en) * | 2006-12-21 | 2008-06-03 | United States Gypsum Company | Expanded perlite annealing process |
| WO2008118827A1 (en) | 2007-03-23 | 2008-10-02 | World Minerals, Inc. | Metal compound coated particulate mineral materials, methods of making them, and uses thereof |
| CN101503591B (en) * | 2009-03-03 | 2011-06-01 | 公安部四川消防研究所 | Aqueous low smoke low toxicity fire-resisting paint for thin section steel structure and preparation thereof |
| CN102219357A (en) * | 2011-05-16 | 2011-10-19 | 四川嘉华企业（集团）股份有限公司 | Production process and equipment for hollow glass microbeads |
| CN102350135B (en) * | 2011-08-08 | 2013-09-18 | 杰成纯水设备科技(太仓)有限公司 | Production method of pearlite filter element |
| US20200206665A1 (en) * | 2017-08-31 | 2020-07-02 | Imerys Filtration Minerals, Inc. | High density perlite filter aid |
| US11527835B2 (en) * | 2017-09-15 | 2022-12-13 | Commscope Technologies Llc | Methods of preparing a composite dielectric material |
| CN107805084A (en) * | 2017-11-21 | 2018-03-16 | 张家港市华孚实业有限公司 | Perlite expanding method |
| CN113717554A (en) * | 2021-09-27 | 2021-11-30 | 陕西宝塔山创新科技有限公司 | Inorganic weather-resistant concrete protective coating and preparation method thereof |
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