CN101774791A - High-strength acid- and wear-resistant spray paint for acid medium atmosphere industrial furnace lining - Google Patents
High-strength acid- and wear-resistant spray paint for acid medium atmosphere industrial furnace lining Download PDFInfo
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- CN101774791A CN101774791A CN200910060473A CN200910060473A CN101774791A CN 101774791 A CN101774791 A CN 101774791A CN 200910060473 A CN200910060473 A CN 200910060473A CN 200910060473 A CN200910060473 A CN 200910060473A CN 101774791 A CN101774791 A CN 101774791A
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Abstract
The invention discloses high-strength acid- and wear-resistant spray paint for an acid medium atmosphere industrial furnace lining, which belongs to the technical field of refractory material. The spray paint comprises the following raw material components in percentage by weight: 55 to 65 percent of industrial ceramic waste, 5 to 15 percent of flint clay powder, 3 to 6 percent of micro silicon powder, 20 to 30 percent of portland cement, 0.1 to 0.8 percent of FND high-efficiency water reducer, and 1 to 1.5 percent of dextrin. The chemical composition of the ceramic waste is as follows: Al2O3<=30 percent, SiO2<=60 percent. The ceramic waste is crushed into 0.088 to 5mm granular material. The high-strength acid- and wear-resistant spray paint of the invention has the advantages of compact structure, stable volume, high strength, erosion resistance, simple construction method and higher mechanical degree. Because the ceramic waste is adopted to serve as the aggregate of the high-strength acid- and wear-resistant spray paint of the invention, the spray paint of the invention not only has excellent performance, but also has low cost, and is applicable to large-area popularization and use.
Description
Technical field
The invention belongs to technical field of refractory materials, be specifically related to that a kind of acid resistance that is used for acidic medium atmosphere industrial furnace equipment liner is good, intensity is high, volume stability, the anti-spray material that washes away.
Background technology
In the prior art, blast furnace raw gas system's cyclone dust or gravitational precipitator are the one-level depositing dust treating plants that blast furnace produces coal gas aborning, its groundwork principle is: the velocity of flow of utilizing the space of fly-ash separator to slow down furnace gas, rely on the deadweight of stove dirt, with the sedimentation of stove dirt, removal big slightly in the furnace gas.Because the fly-ash separator inwall brute force that is subjected to high velocity air is washed away (gas velocity is about 10m/s) in the course of the work; and long term operation is in the gas of acidic medium (as P, S, N, water of condensation etc.); therefore be the protection inwall; usually build or spray the inner lining material of one deck acid-proof wear-proof by laying bricks or stones on its surface; convention liner is generally built by laying bricks or stones by high alumina brick or one-level clay brick; have yet and use spray material FH-140, but work-ing life is all not long, is generally 3~6 months.
Sinter machine large flue groundwork principle is: in the sintering pallet operational process, along the equally distributed vacuum fan of large flue bellows the agglomerate zone of combustion on the chassis is progressively burnt downwards, until the whole sintering of sintering ore bed.Equally; for not being subjected to the brute force of high velocity air in the course of the work, protection sinter machine large flue do not wash away that (gas velocity is about 15~25m/s); and the erosion of the acidic medium in the gas (as P, S, N, water of condensation etc.); also will be or cover the inner lining material of one deck acid-proof wear-proof on its surface; generally build by laying bricks or stones by clay brick; thickness of inner lining is generally 115mm, 30~50 days work-ing life.
In metallurgy industry, also have many and the similar equipment of aforesaid device, in the prior art, their liner all adopts neutral material, aluminium content is higher, and the applicant thinks that their damage mechanism is: at first under acidic medium corrodes, cause inner lining material self strength degradation, and then under the washing away of high velocity air, progressively form and peel off damage, have a strong impact on the normal operation of equipment.At present, still there are not available techniques scheme that successfully solves above-mentioned technical barrier and the high-strength acid-proof wear-proof spray material of the high-quality that is applicable to above-mentioned condition.
Summary of the invention
Above-mentioned deficiency at prior art, the technical problem to be solved in the present invention provides a kind of high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining, overcome the convention liner material and under long-term acidic medium effect, peeled off the defective serious with acid etching, and with low cost, use suits large area to popularize.
Technical scheme of the present invention is: the high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining is made up of following material component and weight percentage:
Industrial ceramics waste material 55~65%;
Flint clay powder 5~15%;
SILICA FUME 3~6%;
Silicate cement 20~30%;
With above-mentioned material component mixture weight is that benchmark adds following admixture:
FDN high efficiency water reducing agent 0.1~0.8%;
Dextrin 1~1.5%.
Described industrial ceramics waste material is broken for the particulate state material of 0.088~5mm.
Described industrial ceramics waste material is meant high temperature electromagnetism bottle ceramic waste material or civilian tableware ceramic waste material or sanitary equipment ceramic waste material or vase ceramic waste material, or the two or more hybrid ceramic waste material among the above ceramic waste material.
In the chemical constitution of described industrial ceramics waste material: AL
2O
3≤ 30%, SiO
2〉=60%.
The granularity of described flint clay powder≤180 orders.
Described SILICA FUME is SiO
2〉=92%, meso-position radius is 0.3 μ m, the powder of granularity≤1 μ m.
Described silicate cement is the 525# ordinary portland cement.
Main component in the high-strength acid-proof wear-proof spray material of the present invention is formed by the higher raw material of silicone content, itself has acidproof erosive excellent properties, therefore overcome the convention liner material effectively and under long-term acidic medium effect, peeled off the defective serious with acid etching, high-strength acid-proof wear-proof spray material compact structure of the present invention, volume stability, intensity height, anti-washing away, constructional method is simple, and mechanization degree is higher.Owing to adopted ceramic waste material to do the aggregate of the high-strength acid-proof wear-proof spray material of the present invention, make not only excellent property of spray material of the present invention, and also with low cost, use suits large area to popularize.
Embodiment
Below the specific embodiment of the present invention and relevant technologies problem are described in further detail.The applicant had carried out a large amount of investigation to existing acidic medium atmosphere industrial furnace equipment liner short problem in work-ing life in the prior art before making the present invention, now lift an example explanation.
Certain producer successively attempts various high-strength wearable materials in order to overcome fly-ash separator inner lining material not long defective in work-ing life, in order to improve the work-ing life of equipment liner, below is two inner lining material performance and service conditions that factory produced.
Table 1 certain factory's high-abrasive material performance and service condition
Though the material of two producers enumerating in the table is all pretty good from index, also useful corundum ceramic piece assembling, but actual service condition is not ideal, and the situation of peeling off is serious, do not grow work-ing life (all being less than 1 year), this mainly is because above-mentioned working lining main component is Al
2O
3, being neutral material, it exists the disadvantage of tradition with material equally, acidproof aggressiveness is poor, and acidic medium at first eats away the matrix part, causes the strength of materials to reduce, carry secretly at blast air under the washing away of dust, inner lining material progressively peels off, damage at last, and the thermal stability of goods is very poor, so even intensity is good also of no avail again, the unfavorable major cause of its service condition that Here it is, and its material price is all higher, and the general user is beyond affordability.
Be described in detail technological thought of the present invention below.At first narrate the technological thought that the present invention selects framework material.At present, the domestic material that is used for working conditions of the present invention generally is as framework material with high alumina matter or corundum material.They belong to neutral material together, and aluminum content is higher, and its acid resistance is all not ideal enough, and compact structure, have played negative impact for the heat insulation effect of equipment.Corundum material cost is higher, and unsuitable large-scale popularization is used.
Through relatively proving repeatedly, the applicant determines that (the ceramic industry waste material belongs to product waste materials such as high temperature electromagnetism bottle, aluminium content AL with the aggregate of ceramic industry waste material as this material
2O
3≤ 30%, SiO
2〉=60%), the reason of selecting: at first, ceramic waste material silicone content height, the sintering temperature that needs is low, is forging back ceramicization degree height through the high temperature burning, the particle densification, the hardness height, and volume stability is good, and importantly ceramic waste material belongs to the semi silica material, have acid resistance preferably, be applicable to the industrial and mineral condition of equipment used fully.And ceramic waste material proportion is little with respect to high alumina or corundum material, and is highly beneficial to the insulation of equipment.Ceramic waste material is the waste material utilization, has not only reduced the cost of spray material, has saved resource, hews out a new road for the development and use of ceramic industry waste material simultaneously.
Narrate the technological thought that the present invention selects substrate material again.Flint clay is the representative of China's high-quality flint clay, the flint clay Al after the calcining
2O
3Content about 40~44%, Fe
2O
3Be not more than 2%, stable components, quality is even, compact structure, water-intake rate is low, and section is conchoidal.The flint clay powder belongs to the semi silica material, has acid resistance preferably, is more satisfactory substrate material.
At last, the technological thought of wedding agent is selected in narration.Bond material is to guarantee that spray material possesses the key of higher intensity, and thermohardening wedding agent (resin) and air-setting wedding agent (colloidal sol) are because the restriction of equipment work temperature all can not obtain the ideal structural strength, and wear resistance also can be had a greatly reduced quality.And hydraulicity wedding agent (silicate cement) belongs to basic material, enough structural strengths are arranged under normal temperature and medium temperature condition, and acidproof aggressiveness is strong, produce simple, easy construction, though decrease, in aforesaid device normal working temperature scope, still can satisfy the required requirement of strength of liner works better with temperature rising intensity.
Principal feature of the present invention: the characteristic of selecting to utilize the higher starting material of silicone content (comprising ceramic waste material) self acid resistance excellence; it is good to develop the acidproof aggressiveness that is fit under the corresponding working condition; the spray material that antistripping and wear resistance are strong; traditional to replace as similar industrial furnace apparatus inner lining material---high alumina matter or corundum materials such as fly-ash separator and sinter machine large flue liners; reach the work-ing life that prolongs the lining body; reduce cost the purpose of protection environment.
A specific embodiments of the present invention is described below.Adopt before the present invention, the used inner lining material of certain 5# of iron and steel group blast furnace cyclone dust is spray material FN-130 and FN-140, what 4# blast furnace cyclone dust liner adopted is the assembling corundum ceramic piece, general all after using three months working face begin to take place serious acidic medium and corrode, peel off, progressively cause liner to form the cavity, have a strong impact on the normal operation of this equipment.
Through relatively selection in many ways, the new No. 5 blast furnace raw gas system cyclone dusts of certain iron and steel group were finally selected high-strength acid-proof wear-proof spray material of the present invention for use in 2008, and its ingredient groups becomes to see Table 2.
The high-strength acid-proof wear-proof spray material of table 2 the present invention material mixture ratio
Material is formed (%) | The industrial ceramics waste material | The flint clay powder | SILICA FUME | Silicate cement | ??FDN | Dextrin |
High-strength acid-proof wear-proof spray material | ??60 | ??15 | ??5 | ??20 | ??0.4 | ??1 |
The spray material performance test results that the applicant provides sees the following form:
The high-strength acid-proof wear-proof spray material of table 3 the present invention physicals detected result
The high-strength acid-proof wear-proof spray material of table 4 the present invention acid resistance detected result
Annotate: test is a sulfuric acid with acid
High-strength acid-proof wear-proof spray material of table 5 the present invention and the contrast of corundum pouring material wear resisting property detected result
Find out that from table 1,3 spray material of the present invention (about 400 ℃) volume density in operating temperature range is 1.95g/cm
3, and high alumina matter spray material and corundum matter coating volume density generally are respectively 〉=2.4g/cm
3With 〉=2.7g/cm
3, fast from normal angled volume density high heat transfer.Obviously, spray material heat insulation effect of the present invention is far better with respect to high alumina matter spray material and corundum matter coating in the above-mentioned materials.From intensity spray material of the present invention in operating temperature range folding strength all 〉=11MPa, ultimate compression strength all 〉=71MPa, the intensity of it and high alumina matter spray material and corundum matter coating is equally matched, and (folding strength of corundum matter coating is 10~16MPa), the test of associative list 5 as can be seen, spray material of the present invention is close substantially with corundum matter spray material abrasion loss in operating temperature range, and (spray material of the present invention is 1.8~2.8cm
3, corundum matter coating is 1.7~2.4cm
3), this has proved that effectively spray material of the present invention and high alumina matter spray material and corundum matter coating have very close physical property under the working order that does not have the acidic medium effect, can replace fully.
The most outstanding characteristics of spray material of the present invention as seen from Table 4 are: have the superior acid resistance energy.Spray material of the present invention (soaks 72h in 20% concentration sulfuric acid) under 80 ℃ of temperature condition under the working order of the most abominable acid effect loss of strength only has 6.7%, saturation 3.64mm, etch degree 1.66mm, and the under equal conditions general etch degree of high alumina matter spray material is 4~6mm, about saturation 10mm, visible its acid-resistant property of spray material of the present invention is that high alumina matter spray material or corundum matter coating are unrivaled.
Since spray material of the present invention was finished from constructing on the new No. 5 blast furnace raw gas system cyclone dusts of certain iron and steel group at the beginning of 2008 8 months, using so far, (in January, 2009) still stood intact.Judge that according to the applicant spray material of the present invention at least can also 5~8 years of works better (early stage commerical test material of the present invention was once used, and used nearly 10 years) in Nanjing Mei Shan coke-oven plant sinter machine smokestack.This compares with the multiple similar spray material of prior art, is a brand-new breakthrough technically, meets the state basic policy of the green anti-material of present promotion fully, for a new road has been opened up in China's energy-saving and emission-reduction.
Claims (7)
1. high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining, it is characterized in that: described high-strength acid-proof wear-proof spray material is made up of following material component and weight percentage:
Industrial ceramics waste material 55~65%;
Flint clay powder 5~15%;
SILICA FUME 3~6%;
Silicate cement 20~30%;
With above-mentioned material component mixture weight is that benchmark adds following admixture:
FDN high efficiency water reducing agent 0.1~0.8%;
Dextrin 1~1.5%.
2. the high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining according to claim 1, it is characterized in that: described industrial ceramics waste material is broken for the particulate state material of 0.088mm~5mm.
3. the high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining according to claim 1, it is characterized in that: described industrial ceramics waste material is meant high temperature electromagnetism bottle ceramic waste material or civilian tableware ceramic waste material or sanitary equipment ceramic waste material or vase ceramic waste material, or the two or more hybrid ceramic waste material among the above ceramic waste material.
4. the high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining according to claim 1 is characterized in that: in the chemical constitution of described industrial ceramics waste material: AL
2O
3≤ 30%, SiO
2〉=60%.
5. the high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining according to claim 1 is characterized in that: the granularity of described flint clay powder≤180 orders.
6. the high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining according to claim 1, it is characterized in that: described SILICA FUME is SiO
2〉=92%, meso-position radius is 0.3 μ m, the powder of granularity≤1 μ m.
7. the high-strength acid-proof wear-proof spray material that is used for acidic medium atmosphere industrial furnace lining according to claim 1, it is characterized in that: described silicate cement is the 525# ordinary portland cement.
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Family Cites Families (3)
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2009
- 2009-01-09 CN CN200910060473XA patent/CN101774791B/en active Active
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CN102173667B (en) * | 2011-01-25 | 2012-11-21 | 常州工程职业技术学院 | Non-intumescent fireproofing coating and preparation method thereof |
CN102815955A (en) * | 2012-08-29 | 2012-12-12 | 江苏恒耐炉料集团有限公司 | Anti-skinning spray coating material for cement kiln |
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CN104418564B (en) * | 2013-08-19 | 2016-04-13 | 上海维乐耐磨材料有限公司 | A kind of wear-resistant ceramic mortar and using method thereof |
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CN103864441A (en) * | 2014-02-17 | 2014-06-18 | 河南省宏达炉业有限公司 | Wear-resistant spray coating |
CN103911029A (en) * | 2014-03-21 | 2014-07-09 | 苏州宇希新材料科技有限公司 | Powder material used for exterior coating |
CN103897445A (en) * | 2014-03-21 | 2014-07-02 | 苏州宇希新材料科技有限公司 | Nano paint for outer walls |
CN103911029B (en) * | 2014-03-21 | 2015-04-22 | 苏州宇希新材料科技有限公司 | Powder material used for exterior coating |
CN110436946A (en) * | 2019-08-15 | 2019-11-12 | 中冶武汉冶金建筑研究院有限公司 | A kind of acidproof spray paint for hot-blast stove vault high temperature position |
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