CN101628813A - SiC ceramic heat exchanger, SiC ceramic material and production method thereof - Google Patents
SiC ceramic heat exchanger, SiC ceramic material and production method thereof Download PDFInfo
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- CN101628813A CN101628813A CN200810140565A CN200810140565A CN101628813A CN 101628813 A CN101628813 A CN 101628813A CN 200810140565 A CN200810140565 A CN 200810140565A CN 200810140565 A CN200810140565 A CN 200810140565A CN 101628813 A CN101628813 A CN 101628813A
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Abstract
The invention discloses a SiC ceramic heat exchanger, a SiC ceramic material and a production method thereof. A formulation of the Sic ceramic material contains a base material component A, an aggregate component B and a bonding agent. In percentage by weight as unit, the A contains 10 to 20 percent of SiC powder, 15 to 25 percent of clay powder, 10 to 15 percent of mullite powder, 5 to 10 percent of silica micro powder, 5 to 10 percent of metal silicon powder, and 2 to 5 percent of talcum powder. The B contains 50 to 60 percent of SiC aggregate; and the weight ratio of the component A to the component B is 1-1.5: 1-1.5. When the ceramic material is produced, the A is prepared into mud cakes first, then the B and the bonding agent are added into the A, and the mixture is prepared into the ceramic material through mud stirring, ageing, mixing, molding, drying and sintering. The sintering temperature is between 1,350 and 1,450 DEG C, and the sintering time is 36 to 52 hours. The SiC ceramic heat exchanger has the advantages of high temperature resistance, high heat conduction, thermal shock resistance, corrosion resistance, long service life and energy conservation; and the production method for the SiC ceramic heat exchanger is mature, and is put into the industrialized production for more than one year.
Description
One, technical field:
The present invention relates to a kind of interchanger, refractory materials and production method thereof, particularly a kind of sic ceramic heat exchanger, sic stupalith and production method thereof.
Two, background technology:
Produce and use the novel high-efficiency and energy-saving sic ceramic heat exchanger that can satisfy various kilns not find as yet at present, for example: (1) with high alumina and compound clay be raw material through mix, steps such as moulding, oven dry, sintering produce coiled heat-exchange ceramic pipe with integral seamless structure; (2) to give birth to localized raw materials such as ripe flint clay, soft clay, be wedding agent, adopt and roll membrane process synthetic cordierite high temperature ceramic heat-exchanger with water-soluble organic polymer.But the interchanger great majority that now use are metallic recuperator, and can only use at low temperatures, can not directly use when fuel gas temperature is higher, mix a large amount of freezing airs, and necessary high temperature protection, as drum cold blast engine and Controlling System.The temperature that interchanger reclaims after mixing freezing air will reduce, and poor, the heat exchange weak effect of interchanger heat conductivility of material produce such as trichroite, mullite, high alumina, flint clay causes energy dissipation.
Owing to be becoming tight current energy day, and rate of energy is lower, has caused a large amount of wastes of the energy since like this, in order to improve rate of energy, is badly in need of producing and the product of use good energy-conserving effect.And ceramic heat exchanger is one of torch plan of country, is Chinese power-saving technology policy outline appointed product, also is one of new high-tech product of encouraging foreign investment.Therefore and sic matter ceramic heat exchanger has improved a class to ceramic heat exchanger, steps on a new stage again, produces a kind of efficient, environmental protection, energy-conservation, sic ceramic heat exchanger is very important.
Three, summary of the invention:
The object of the invention: be to overcome the problem that exists in the above-mentioned background technology, invent a kind of sic ceramic heat exchanger, the object of the invention also is to provide a kind of sic stupalith and production method thereof.
Technical scheme of the present invention:
The present invention proposes a kind of efficient sic ceramic heat exchanger, stupalith and production method thereof, and its production technique may further comprise the steps:
Raw material is chosen and preparation, wet ball mill, filtration, magnetic separation, filter mud, stirring, pugging, old, concise, extrusion molding, drying, sintering, inspection after construction, assembling warehouse-in, and its detailed step is:
1, the weight percent of choosing and filling a prescription of raw material is:
The weight ratio of A, B two components is 1～1.5: 1～1.5, adds the wedding agent methylcellulose gum that accounts for A, B two component gross weights 0.5～1% again.
2, earlier 〉=200 purpose matrix material are added water (weight ratio of water and matrix material is 1: 3) and send into the wet bulb grinding machine and grind 10-12h, the standard of Assay size is: granularity 〉=320 orders.
3, sending the mud worn into to the plate hole mud press by sieving, magnetic separation, to filter into mud cake standby.
4, with mud cake with after aggregate mixes, send into mixed milling in the double-shaft two-way mixer, and add the wedding agent methylcellulose gum, moisture controlled is advisable at 16%-20%, mixes 2-3 time by pug mill, send old old.
5, after old old the depositing (15 ± 1 days winters, 10 ± 1 days summers), by behind concise 2 times of the pug mill, send forcing machine specification on request to carry out extrusion moulding again.
6, seasoning 20-24h after the moulding enters baking room and dries moisture content≤1.5% and can go into stove.
7, base substrate is used the shuttle kiln sintering, sintering temperature is controlled between 1350--1450 ℃, and the son of fighting routinely burns till 36-52h, and insulation 4-6h is cooled to come out of the stove below 500 ℃.
8, the qualified back assembling of the component test that sintering is finished warehouse-in (high-temperature seal adhesive is used in assembling, with anti-gas-leak).
A kind of sic ceramic heat exchanger, contain inlet of cold air and hot air outlet, last heat exchange box, following heat exchange box, heat pipe, inlet of cold air is connected on last heat exchange box both sides respectively with hot air outlet, between the inlet of cold air hot air outlet of last heat exchange box, be provided with seal diaphragm, the heat pipe of some amount to be installed between last heat exchange box base plate and following heat exchange box upper plate, carry out heat exchange by air in the heat pipe, form exhaust gases passes between the heat pipe at interval.
The heat pipe of some amount is connected and fixed at upper and lower heat exchange box and is uniform arrangement between the plate, and perhaps staggered arrangement is arranged, and the cross section of heat pipe is a hollow circular.
The heat pipe of some amount is built bent sealing by laying bricks or stones and is decided between the web plate to be uniform layout upper and lower.Or staggered arrangement arranges, and bent envelope web plate or sic heat pipe are connected with heat exchange box up and down, and the employing high-temperature seal adhesive is tightly connected, and the cross section of heat pipe is a hollow circular.
Build large-scale sic ceramic heat exchanger by laying bricks or stones and adopt bent envelope web plate, bent envelope warming plate, long 600-1200mm, wide 400-600mm, thickness 40-50mm, the middle connection adopted the high-temperature seal adhesive connection, and leak rate is low, and it is more flexible to build the interchanger specification by laying bricks or stones.
Positive beneficial effect of the present invention: mainly be save energy, the protection environment.
(1) sic ceramic heat exchanger of the present invention is high temperature resistant, thermal conductivity is high, anti-thermal shock, anti-erosion, save energy ratio are big.The sic ceramic heat exchanger is put into the highest place of the nearest temperature of flue outlet, if when the temperature of kiln is 1500 ℃, the flue outlet temperature should can exchange for about temperature 400-800 ℃ at 1200-1300 ℃; Utilize 600 ℃ of heat exchange air and combustion gas to form gas mixture and burn, originally every stove uses 2.6 tons of diesel oil, uses 1.25 tons of diesel oil, capable of saving fuel 52% after utilizing the sic ceramic heat exchanger.
(2) the sic ceramic heat exchanger of the invention, suitability is strong, can adapt to all temps and environment, good effect of heat exchange (400-800 ℃ of heat exchange temperature), long service life (kiln 5-10 continuously).
(3) the production method maturation of sic ceramic heat exchanger of the present invention, sic stupalith to drop into formal production more than a year, is suitable for suitability for industrialized production, has good social, economic benefit.
Four, description of drawings
Fig. 1 is the technological process of production figure of sic stupalith of the present invention.
Fig. 2 is whole sic ceramic heat exchanger.
Fig. 3 is two circulations and many circulations sic ceramic heat exchanger.
Fig. 4 is bent envelope, heat pipe, web plate.
Fig. 5 is bent envelope warming plate.
Five, embodiment
Embodiment one: sic stupalith and production method thereof
Its production craft step comprises that raw material is chosen with preparation, ball milling, sieving, magnetic separation, filtration, stirring, pugging, old, concise, extrusion moulding, drying, sintering, inspection after construction, assembling and puts its detailed step in storage and be:
Prescription: 1, take by weighing the matrix material: sic powder 10%, clay powder 15%, mullite powder 10%, silicon powder 5%, metallic silicon power 5%, talcum powder 5%.
Take by weighing aggregate: sic0-0.5,50%, matrix material and aggregate weight ratio 1: 1 add the wedding agent methylcellulose gum of matrix material and aggregate gross weight 0.5%.
2, by matrix material formula computation weigh, 〉=200 purpose matrix material are added water (water and matrix material weight ratio are 1: 3) send into and grind 10-12h in the wet bulb grinding machine, the Assay size standard is: granularity is 〉=320 orders.
3, with the mud worn into by sieving, magnetic separation, sending the plate hole mud press to, to filter into mud cake standby.
4, with mud cake with after aggregate mixes, send into the double-shaft two-way stirrer for mixing and stir, and add the wedding agent methylcellulose gum, moisture controlled is advisable at 16-20%, practices system 2-3 time by pug mill.
5, send old old (summer old 10 days ± 1, winter old 15 days ± 1) mud of practicing after, by behind concise 2 times of the pug mill, send forcing machine specification on request to carry out extrusion moulding again.
6, seasoning 20-24h after the moulding enters baking room and dries moisture content≤1.5% and can advance stove.
7, base substrate is used the shuttle kiln sintering, sintering temperature is controlled at 1400 ℃, and sintering 36h is incubated 6h routinely, is cooled to come out of the stove below 500 ℃.
8, according to the described production method of claim 5, it is characterized in that: described sintering is when heating up, temperature temperature rise rate between 100-200 ℃ is 10-15 ℃/h, temperature rise rate is 30-35 ℃/h between 200-600 ℃, temperature rise rate is 35-45 ℃/h between 600-900 ℃, and temperature rise rate is 55-60 ℃/h between 900-1450 ℃, insulation 1h in the time of 600 ℃, insulation 1h in the time of 900 ℃ finishes firing temperature insulation 4h.
9, the qualified back assembling of the component test that sintering is finished warehouse-in uses the high-temperature seal adhesive sealing, with anti-gas-leak during assembling.
Embodiment two: sic stupalith and production method thereof, and basic identical with embodiment one, something in common is no longer narrated, and difference is:
1, takes by weighing matrix material sic powder 20%, clay powder 10%, mullite powder 10%, silicon powder 3%, metallic silicon power 5%, talcum powder 3%.
Take by weighing aggregate 0-0.5sic50%; Matrix material and aggregate weight ratio are 1: 1, add 1% wedding agent methylcellulose gum of matrix material and aggregate gross weight.
2, sintering temperature is controlled at 1430 ℃, and sintering 48h is incubated 4h routinely, is cooled to come out of the stove below 500 ℃.
Embodiment three: sic stupalith and production method thereof, and it is basic identical to execute example two with embodiment one, and something in common is no longer narrated, and difference is:
1, takes by weighing the matrix material: sic powder 15%, clay 10%, mullite 12%, silicon powder 4%, metallic silicon power 6%, talcum powder 3%.
Aggregate 0-1sic50%, the weight ratio of matrix material and aggregate adds 1% wedding agent methylcellulose gum of matrix material and aggregate gross weight at 1: 1.
2, temperature is controlled at 1450 ℃ during sintering, sintering 48h routinely, and insulation 5h is cooled to come out of the stove below 500 ℃.
Embodiment four: sic stupalith and production method thereof and preceding basic identical, and difference is:
1, takes by weighing the matrix material: sic powder 15%, clay 15%, mullite powder 15%, silicon powder 3%, metallic silicon power 5%, talcum powder 4%.Aggregate 0-0.5sic45%, wedding agent 0.5%
Embodiment five: take by weighing the matrix material: sic powder 10%, clay 13%, mullite 10%, silicon powder 5%, metallic silicon power 5%, talcum powder 3%.
Aggregate: 0-0.5sic55%, wedding agent 1%.
Embodiment six: sic stupalith of the present invention and production method thereof are made the sic ceramic heat exchanger.
Embodiment joins figure (1): be the production technique schema.
Embodiment joins figure (2): among the figure 1 in the interchanger top box, figure 2 among interchanger nowel, the figure 3 among sic heat pipe, the figure 4 among exhaust gases passes, the figure 5 among seal diaphragm, the figure 6 for 7 being hot air outlet among inlet of cold air, the figure.The heat pipe of some amount vertical evenly layout between 1-2 arranged or the staggered arrangement arrangement, and heat pipe is a hollow circular.
Embodiment seven: the large-scale sic ceramic heat exchanger of the present invention has two circulations and many circulations comparatively flexible, can according to use producer require the design cycle number of times what, make the sic ceramic heat exchanger.
Embodiment joins figure (3): among the figure 1 in the last heat exchange box, figure 2 among heat exchange box, the figure down 3 among heat pipe, the figure 4 among exhaust gases passes, the figure 5 among seal diaphragm, the figure 6 for 7 being hot air outlet among inlet of cold air, the figure.The heat pipe of some amount arranges evenly in the 1-2 intermediate vertical and arranges or the staggered arrangement arrangement that heat pipe is a hollow circular.
Embodiment joins figure (4): this figure and is bent envelope heat pipe web plate: 13 is bent envelope of bent envelope heat pipe web plate for building in part, figure within the walls 2 by laying bricks or stones in for heat pipe connecting hole, figure among the figure.
Embodiment joins figure (5): this figure and is bent envelope warming plate: 1 connects bent the envelope for building in part, figure within the walls 3 by laying bricks or stones for bent envelope warming plate among the figure.
Claims (10)
1, a kind of sic stupalith is characterized in that: contain the matrix material in the prescription, component A, aggregate component B and wedding agent are unit with the weight percent.
Contain sic powder 10%～20%, clay powder 15%～25%, mullite powder 10%～15%, silicon powder 5%～10%, metallic silicon power 5%～10%, talcum powder 2%～5% among the matrix material component A.
Contain sic50%～60% in the aggregate component B.
The weight ratio of A, B two components is 1～1.5: 1～1.5 in the prescription, and wedding agent accounts for 0.5%～1% of A, B two component gross weights.
2, sic stupalith according to claim 1 is characterized in that: the sic aggregate 50%～60% of 0～0.5mm in the described aggregate component B.
3, sic stupalith according to claim 1 is characterized in that: described wedding agent is a methylcellulose gum.
4, a kind of production method of sic stupalith comprises preparation of raw material, mixes, moulding, oven dry, sintering, inspection after construction, it is characterized in that:
(1) take by weighing matrix material A by prescription, in the matrix material: the ratio of water=3: 1 adds water, advances the wet bulb grinding machine and grinds 10-12h, and grinding back granularity inspecting standard is 〉=320 orders;
(2) then the mud that grinds to form is passed through the screening magnetic separation, enter plate hole filter mud machine filter and become mud cake standby;
(3) aggregate B and mud cake are mixed stirring, add wedding agent, mix by stirrer, by vacuum pugging, water content is controlled at 16%-20%;
(4) mud of practicing is carried out old depositing, the old time is 15 ± 1 days winters, and in 10 ± 1 days summers, it is concise to put into pug mill again, and extrusion moulding then, drying make base substrate moisture below 1.5%;
(5) with blank sintering, sintering temperature 1350-1450 ℃, sintering time is 36-52h, and insulation 2-4h comes out of the stove after the cooling.
5, according to the described production method of claim 4, it is characterized in that: the described dry seasoning that is earlier, be 20～24 hours time of drying, laggard baking room is dried moisture≤1.5.
6, according to the described production method of claim 5, it is characterized in that: described sintering is when heating up, temperature temperature rise rate between 100-200 ℃ is 10-15 ℃/h, temperature rise rate is 30-35 ℃/h between 200-600 ℃, temperature rise rate is 35-45 ℃/h between 600-900 ℃, and temperature rise rate is 55-60 ℃/h between 900-1450 ℃, insulation 1h in the time of 600 ℃, insulation 1h in the time of 900 ℃ finishes firing temperature insulation 4h.
7, a kind of sic ceramic heat exchanger, contain inlet of cold air and hot air outlet, last heat exchange box or following heat exchange box, heat pipe, it is characterized in that: inlet of cold air is connected with last heat exchange box both sides respectively with hot air outlet, is provided with seal diaphragm between the inlet of cold air of last heat exchange box and hot air outlet, and the heat pipe of some amount is installed between web plate at the bottom of the last heat exchange box and following heat exchange box upper junction plate, by the air heat exchange, form exhaust gases passes between the heat pipe at interval in the heat pipe.
8, sic ceramic heat exchanger according to claim 7 is characterized in that: the heat pipe of some amount is connected and fixed at upper and lower heat exchange box and is uniform arrangement between the plate, or is staggered, and the cross section of heat pipe is a hollow circular.
9, a kind of large-scale sic ceramic heat exchanger, the refractory brick that contains two sides is built wall by laying bricks or stones, upper and lower heat exchange box, inlet of cold air or hot air outlet, build bent envelope warming plate by laying bricks or stones, build bent sealing by laying bricks or stones and decide web plate, heat pipe, it is characterized in that: both sides refractory brick is built wall by laying bricks or stones and is built song by laying bricks or stones and seal up warming plate, build song by laying bricks or stones and seal up the heat pipe retaining plate, and the sealing plate at two ends constitutes upward heat exchange box with central dividing plate, be respectively equipped with inlet of cold air, hot air outlet on the both sides of last heat exchange box, between inlet of cold air and hot air outlet, be provided with seal diaphragm.Build bent envelope web plate by laying bricks or stones and build heat pipe retaining plate and sealed at both ends plate by laying bricks or stones at following heat exchange box, there is heat exchange box under the seal diaphragm formation centre.Upper and lower heat exchange box is built the heat pipe that bent sealing decides to be fixedly connected with between the heat pipe web plate some amount by laying bricks or stones, and described heat pipe is communicated with upper and lower heat exchange box, by the air heat exchange, forms exhaust gases passes between the heat pipe in the heat pipe.
10, sic ceramic heat exchanger according to claim 9, it is characterized in that: the heat pipe of some amount is built bent sealing by laying bricks or stones and is decided between the web plate to be uniform distribution upper and lower, or staggered arrangement is arranged, bent shrouding connects, heat pipe is connected with heat exchange box up and down, the employing high-temperature seal adhesive connects, and the cross section of heat pipe is a hollow circular.
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| CN200810140565A CN101628813A (en) | 2008-07-14 | 2008-07-14 | SiC ceramic heat exchanger, SiC ceramic material and production method thereof |
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| CN200810140565A CN101628813A (en) | 2008-07-14 | 2008-07-14 | SiC ceramic heat exchanger, SiC ceramic material and production method thereof |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107421117A (en) * | 2017-06-30 | 2017-12-01 | 翟延军 | A kind of SiC ceramic coil pipe hot-blast stove and preparation method thereof |
| CN107419047A (en) * | 2017-06-30 | 2017-12-01 | 翟延军 | A kind of high temperature constant temperature blast funnace hot blast stove and preparation method thereof |
| CN107892576A (en) * | 2017-10-25 | 2018-04-10 | 深圳市商德先进陶瓷股份有限公司 | Silicon carbide ceramics and preparation method thereof and fin and its application |
| CN110375566A (en) * | 2019-08-15 | 2019-10-25 | 南通三责精密陶瓷有限公司 | A kind of novel silicon carbide heat exchange module and its manufacturing method |
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2008
- 2008-07-14 CN CN200810140565A patent/CN101628813A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107421117A (en) * | 2017-06-30 | 2017-12-01 | 翟延军 | A kind of SiC ceramic coil pipe hot-blast stove and preparation method thereof |
| CN107419047A (en) * | 2017-06-30 | 2017-12-01 | 翟延军 | A kind of high temperature constant temperature blast funnace hot blast stove and preparation method thereof |
| CN107421117B (en) * | 2017-06-30 | 2018-07-06 | 翟延军 | A kind of SiC ceramic coil pipe hot-blast stove and preparation method thereof |
| CN107892576A (en) * | 2017-10-25 | 2018-04-10 | 深圳市商德先进陶瓷股份有限公司 | Silicon carbide ceramics and preparation method thereof and fin and its application |
| CN107892576B (en) * | 2017-10-25 | 2020-05-05 | 深圳市商德先进陶瓷股份有限公司 | Silicon carbide ceramic and preparation method thereof, and radiating fin and application thereof |
| CN110375566A (en) * | 2019-08-15 | 2019-10-25 | 南通三责精密陶瓷有限公司 | A kind of novel silicon carbide heat exchange module and its manufacturing method |
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Open date: 20100120 |