CN1281912C - Blaze insulating fluidized forge furnace - Google Patents
Blaze insulating fluidized forge furnace Download PDFInfo
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- CN1281912C CN1281912C CN 200410098988 CN200410098988A CN1281912C CN 1281912 C CN1281912 C CN 1281912C CN 200410098988 CN200410098988 CN 200410098988 CN 200410098988 A CN200410098988 A CN 200410098988A CN 1281912 C CN1281912 C CN 1281912C
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- burner hearth
- flue
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Abstract
A flame insulating fluidized calcining furnace of the present invention relates to the technical field of calcining devices. The present invention indirectly heats a calcining furnace of a fluidized bed by using high-temperature flame in combustion, flame is prevented from being directly contacted with material, and the phenomenon that calcinated material in the furnace is over-calcinated is effectively overcome; simultaneously, high-temperature flue gas from a flue is used as fluidized gas to enter a furnace chamber from a passage at the bottom of the furnace chamber from top to bottom to make the furnace chamber of the fluidized calcining furnace heated inside and outside, and the heating time is increased by one time; compared with a fluidized calcining furnace which is provided with a combustion chamber at the bottom and directly burns to heat material, the present invention has the advantage of greatly improvement of heat efficiency. The average residence time of material in the flame insulating fluidized calcining furnace of the present invention can be adjusted from several seconds to numbers of hours, the furnace temperature can be adjusted from 500 DEG C to 1300 DEG C, and the temperature difference of the furnace chamber is between minus 5 and plus 5 DEG C. The flame insulating fluidized calcining furnace of the present invention has the advantages of high heat transferring and mass transferring speed, uniform temperature in the furnace and low energy consumption.
Description
Technical field
Blaze insulating fluidized forge furnace of the present invention and using method relate to the calciner technical field.
Background technology
At present, calciner has fluidized bed calcination stove, rotary kiln, multihearth, tunnel cave etc.Calcine for powder material, fluidized bed calcination stove material conducts heat, mass transfer is fast, and energy consumption is low, and the single device production capacity is big, but directly heating or the combustion chamber is set outward in the existing fluidized bed calcination stove heat-supplying mode stove, cause following problem like this: the one,, fuel is in the stove internal combustion, and flame directly contacts with material, flame holding is poor during concentrated phase, local temperature is too high in the stove, and the material heating temperature is too high around making, causes the material burning; In addition, fuel is emitted heat to external world's heat radiation greatly when external combustion chambers burn, and the heat effective rate of utilization reduces.
Summary of the invention
The objective of the invention is to overcome the defective of existing fluidized bed calcination stove, a kind of blaze insulating fluidized forge furnace is provided, not only have heat transfer, mass transfer is fast, temperature is even in the stove, and energy consumption is hanged down characteristics; And effectively avoid the material burning, and effectively utilize the combustion chamber liberated heat.
For achieving the above object, technical solution of the present invention provides a kind of blaze insulating fluidized forge furnace, comprises furnace top cover, combustor nozzle, the combustion-supporting airduct of secondary, combustion chamber, furnace outer wall, hearth wall, flue, burner hearth, feed pipe, passage, furnace bottom lid, the outlet connecting pipe road, gas-solid separator and cooling discharger; Wherein:
Furnace outer wall is a ducted body, and a plurality of combustor nozzles and feed pipe are set on its lateral circle surface; Combustor nozzle uniform setting on vertical uniform a plurality of contour Zhou Yuan, each combustor nozzle is inner to communicate with the combustion chamber, and both are corresponding one by one, and each combustor nozzle side is provided with the combustion-supporting airduct of secondary;
The combustion chamber is a bell mouth shape, is located at the internal face of furnace outer wall;
Furnace top cover and furnace bottom cover down the two ends up and down that are fixed in furnace outer wall; The furnace top cover central part is provided with the outlet connecting pipe road upward, and outer end, outlet connecting pipe road is the outlet of calciner gas solid mixture, and this outlet communicates with the High Temperature Gas solid separator, and the separator below is the cooling discharger; The outlet connecting pipe road is inner to communicate with the fluidized calcinator burner hearth, and burner hearth is in the middle part of furnace outer wall, is centered on by hearth wall to constitute tubular, with furnace outer wall totally one axis; Hearth wall outer peripheral face and furnace outer wall inner peripheral surface have a gap, and the gap is a flue; The burner hearth bottom position is provided with the passage that flue is connected with burner hearth on hearth wall;
Feed pipe is located at the furnace outer wall bottom to declivity, and the pipeline of feed pipe passes flue and communicates with burner hearth;
Flame partition wall vertically is provided with in the gap of hearth wall outer peripheral face and furnace outer wall inner peripheral surface, and the vertical passage that flame partition wall is separated out is a flue;
Ash removing opening is located at furnace bottom and is covered, and is positioned at the bottom of flue.
Described blaze insulating fluidized forge furnace, its described furnace outer wall, hearth wall, flue, the geometry of burner hearth is cylindrical, square column type or abnormity.
A kind of method of using described blaze insulating fluidized forge furnace, its course of work is as follows:
The combustion air of fuel by burner and secondary air channel be in combustion chamber mixed combustion, and thermal-flame during burning and high-temperature flue gas be by combustion chamber and flue, indirect fluidized bed calcination stove burner hearth; Under the blower fan dynamic action, the high-temperature flue gas in the flue enters burner hearth from the passage of burner hearth bottom as fluidizing gas; The material that enters burner hearth from feed pipe forms fluidization with high temperature fluidized gas in burner hearth mixes, and makes high-temperature gas and material produce heat transfer, mass transfer efficiently; The material that calcining the is good ascension that makes progress is sent into the High Temperature Gas solid separator through the outlet connecting pipe road and is carried out gas solid separation, and hot gas is used for the material preheating, and thermal material crashes into the cooling discharger, through the laggard warehouse of supercooling discharger.
Described method, its burner are automation control, and temperature can be regulated arbitrarily in 500 ℃ of-1300 ℃ of scopes in the stove, in the burner hearth temperature difference ± 5 ℃; This high-temperature flue gas is heated inside and outside making fluidized calcinator, and double heat time heating time, has fully effectively utilized the fuel liberated heat, thermal efficiency height, and make that the interior temperature of fluidized bed calcination stove burner hearth is even, stable.
Described method, its described fluidizing gas, its speed is 0.1---6.0 meter per second scopes.
Described method, its described fuel is combustion gas, fuel oil or coal dust
Described method, its described material, particle mean size is 0---5000 micrometer ranges.
Blaze insulating fluidized forge furnace of the present invention not only has heat transfer, mass transfer is fast, and temperature is even in the stove, and energy consumption is hanged down characteristics; And effectively avoid the material burning, this is narrow for calcination temperature range, it is extremely important to require active high high-performance powder calcination to prepare, and effectively utilizes the combustion chamber liberated heat.
The present invention is a kind of blaze insulating fluidized forge furnace, it is to utilize combustion high temperature flame indirect fluidized bed calcination stove, avoided flame directly to contact with material, combustion flame is stable, effectively overcome calcining materials burn-off phenomenon in the stove, simultaneously, high-temperature flue gas leads to fluidized bed calcination stove passage by flue from the bottom process from top to bottom, enter fluidized bed calcination stove burner hearth, high-temperature flue gas makes in the fluidized calcinator like this, be heated outward, make fluidized calcinator double heat time heating time, this compares with the direct burning heating fluidized calcinator of band combustion chamber, bottom, has improved heat utilization efficiency greatly; And temperature is more even in the calcining furnace.High-temperature flue gas fully mixes with fluidization of material in blaze insulating fluidized forge furnace, has greatly improved the heat transfer of high-temperature flue gas and material, mass transfer rate, and temperature is even in the burner hearth, and the temperature difference is less than ± 5 ℃.
This blaze insulating fluidized forge furnace, be applicable to calcinings such as material decarburization, organic matter, hydroxy water, the crystallization water, CO2, especially the active high powder material of narrow for calcination temperature range, requirement, as: the activation burning of materials such as kaolin, magnesite, talcum, lime stone, aluminium hydroxide prepares the high-performance powder.
Description of drawings
Fig. 1 is a blaze insulating fluidized forge furnace structure chart of the present invention;
Fig. 2 is a blaze insulating fluidized forge furnace structure A-A cutaway view of the present invention;
Fig. 3 is a blaze insulating fluidized forge furnace structure B-B cutaway view of the present invention;
The specific embodiment
As Fig. 1, Fig. 2 and shown in Figure 3, be blaze insulating fluidized forge furnace structure chart of the present invention.Blaze insulating fluidized forge furnace comprises furnace top cover 1, combustor nozzle 2, the combustion-supporting airduct 3 of secondary, combustion chamber 4, furnace outer wall 5, hearth wall 6, flue 7, burner hearth 8, feed pipe 9, path 10, ash removing opening 11, furnace bottom lid 12, flame partition wall 13, outlet connecting pipe road 14, High Temperature Gas solid separator 15, cooling discharger 16.
Wherein, furnace outer wall 5 is a hollow circular cylinder, and a plurality of combustor nozzles 2 and feed pipe 9 are set on its lateral circle surface.Combustor nozzle 2 uniform setting on vertical uniform a plurality of contour Zhou Yuan.Each combustor nozzle 2 the inner communicates with combustion chamber 4, and both are corresponding one by one, and referring to the profile A-A among Fig. 2, each combustor nozzle 2 side is provided with the combustion-supporting airduct 3 of secondary.Combustion chamber 4 is a bell mouth shape, referring to the profile A-A among Fig. 2, is located at the internal face of furnace outer wall 5, and its angle of flare α is determined by the burner combustion situation.
Furnace top cover 1 and furnace bottom lid 12 are fixed in the two ends up and down of furnace outer wall 5 up and down.Furnace top cover 1 central part is provided with outlet connecting pipe road 14 upward, and 14 outer ends, outlet connecting pipe road are the outlets of calciner gas solid mixture, and this outlet communicates with High Temperature Gas solid separator 15, and separator 15 belows are cooling discharger 16.Outlet connecting pipe road 14 is inner to communicate with fluidized calcinator burner hearth 8, and fluidized calcinator burner hearth 8 is in the middle part of furnace outer wall 5, by hearth wall 6 center on constitute cylindric, with furnace outer wall 5 totally one axis; Hearth wall 6 outer peripheral faces and furnace outer wall 5 inner peripheral surface gaps constitute cylinder shape, vertically are provided with flame partition wall 13 in the cylinder shape gap, and the vertical passage that flame partition wall 13 is separated out is a flue 7, referring to the B-B profile of the A-A profile among Fig. 2, Fig. 3.Burner hearth 8 bottom positions are provided with the path 10 that flue 7 is connected with fluidizing calcination burner hearth 8 on hearth wall 6, referring to the B-B profile among Fig. 3.
Furnace bottom lid 12 is provided with ash removing opening 11, and ash removing opening 11 is positioned at the bottom of flue 7.
Blaze insulating fluidized forge furnace burner 2 and combustion chamber 4 the position is set, determine that according to blaze insulating fluidized forge furnace height, cross section size in a longitudinal direction by the decision of calcining furnace height, burner 2 is arranged and is provided with 1 from top to bottom to dozens of; The burner setting can be 1 to dozens of by the size decision of calcining furnace cross section on the cross section.Burner 2 is arranged as top type and staggered.Burner 2 is installed quantity, size is just come to determine by calcining materials character, quantity and calcining heat; Burner 2 setting angles are determined by burner and combustion chamber 4 combustion positions.
The blaze insulating fluidized forge furnace course of work of the present invention is as follows:
Fuel is by burner 2 combustion air 4 mixed combustions in the combustion chamber with secondary air channel 3, and the thermal-flame during burning and high-temperature flue gas pass through combustion chamber 4 and flue 7, indirect fluidized bed calcination stove burner hearth 8; Under the blower fan dynamic action, the high-temperature flue gas in the flue 7 enters fluidized bed calcination stove burner hearth 8 from the path 10 of burner hearth 8 bottoms as fluidizing gas; The material that enters fluidized bed calcination stove burner hearth 8 from feed pipe 9 forms fluidization with high temperature fluidized gas in burner hearth 8 mixes, and makes high-temperature gas and material produce heat transfer, mass transfer efficiently.The material that calcining the is good ascension that makes progress is sent into High Temperature Gas solid separator 15 through outlet connecting pipe road 14 and is carried out gas solid separation, and hot gas is used for the material preheating, and thermal material crashes into cooling discharger 16, through supercooling discharger 16 laggard warehouses.Temperature is regulated control (closed loop is controlled or manually control automatically) by burner 4 fuel quantities and air quantity in the burner hearth 8.When 930 ℃ of design temperatures, when burner hearth 8 is heated to design temperature, burner hearth 8 internal upper parts, middle part, temperature of lower are in 930 ± 5 ℃, at this moment, hard kaoline powder (2 microns of average grain diameters) is added in the fluidized bed calcination stove burner hearth 8 by feed pipe 9, high temperature fluidized gas forms fluidization with powder in fluidized bed calcination stove burner hearth 8 mixes, and carries out flash heat transfer, mass transfer; When reaching material balance, burner hearth 8 temperature stabilizations, still in 930 ± 5 ℃, this moment, sample analysis saw Table one for burner hearth 8 internal upper parts, middle part, temperature of lower, and burning crystallization phenomenon does not take place powder.The blaze insulating fluidized forge furnace heat utilization ratio improves about 10% than external combustion chamber fluidized calcinator.
Table one. the situation of the different calcining manners of hard kaoline powder
| The calcining manners index | Burn mistake/% | Crystalline structure | Whiteness/% |
| Blaze insulating fluidized forge furnace | 15.32 | Amorphous state | 90.72 |
| Directly fluidized calcinator is heated in burning | 15.33 | Amorphous state and crystalline state | 90.73 |
| Thermogravimetic analysis (TGA) | 15.32 | Amorphous state | —— |
When blaze insulating fluidized forge furnace of the present invention moves, the thermal-flame indirect of combustion chamber 4 burning the fluidized bed calcination stove, avoided thermal-flame directly to contact with material, overcome material be heated overheated, simultaneously, high-temperature flue gas enters fluidized bed calcination stove burner hearth 8 from burner hearth 8 foot passages 10 as fluidizing gas from top to bottom by flue 7, high-temperature flue gas is heated inside and outside making fluidized calcinator like this, double heat time heating time, fully effectively utilized the fuel liberated heat, thermal efficiency height, and make that the interior temperature of fluidized bed calcination stove burner hearth is even, stable.
Fluidization gas velocity determined by calcinated powder material character, fluidized state, calcination time, is 0.1---6.0 meter per second scopes; Material mean residence time in stove is decided by material stock amount in the burner hearth 8.Blaze insulating fluidized forge furnace height and area of section are determined by material properties, calcination time, treating capacity and fluidized state.
Blaze insulating fluidized forge furnace fuel used for combustion gas, fuel oil or coal dust all can, require to decide according to calcining materials.
Temperature can be regulated arbitrarily by burner automation control in 500-1300 ℃ of scope in the blaze insulating fluidized forge furnace stove, in the burner hearth temperature difference ± 5 ℃; Furnace atmosphere can be regulated (oxidizing atmosphere, reducing atmosphere).
Blaze insulating fluidized forge furnace calcining materials particle mean size is 0---5000 micrometer ranges.
Claims (7)
1, a kind of blaze insulating fluidized forge furnace comprises furnace top cover, combustor nozzle, the combustion-supporting airduct of secondary, combustion chamber, furnace outer wall, hearth wall, flue, burner hearth, feed pipe, passage, furnace bottom lid, outlet connecting pipe road, gas-solid separator and cooling discharger; It is characterized in that:
Furnace outer wall is a ducted body, and a plurality of combustor nozzles and feed pipe are set on its lateral circle surface; Combustor nozzle uniform setting on vertical uniform a plurality of contour Zhou Yuan, each combustor nozzle is inner to communicate with the combustion chamber, and both are corresponding one by one, and each combustor nozzle side is provided with the combustion-supporting airduct of secondary;
The combustion chamber is a bell mouth shape, is located at the internal face of furnace outer wall;
Furnace top cover and furnace bottom cover down the two ends up and down that are fixed in furnace outer wall; The furnace top cover central part is provided with the outlet connecting pipe road upward, and outer end, outlet connecting pipe road is the outlet of calciner gas solid mixture, and this outlet communicates with the High Temperature Gas solid separator, and the separator below is the cooling discharger; The outlet connecting pipe road is inner to communicate with the fluidized calcinator burner hearth, and burner hearth is in the middle part of furnace outer wall, is centered on by hearth wall to constitute tubular, with furnace outer wall totally one axis; Hearth wall outer peripheral face and furnace outer wall inner peripheral surface have a gap, and the gap is a flue; The burner hearth bottom position is provided with the passage that flue is connected with burner hearth on hearth wall;
Feed pipe is located at the furnace outer wall bottom to declivity, and the pipeline of feed pipe passes flue and communicates with burner hearth;
Flame partition wall vertically is provided with in the gap of hearth wall outer peripheral face and furnace outer wall inner peripheral surface, and the vertical passage that flame partition wall is separated out is a flue;
Ash removing opening is located at furnace bottom and is covered, and is positioned at the bottom of flue.
2, blaze insulating fluidized forge furnace as claimed in claim 1 is characterized in that: described furnace outer wall, and hearth wall, flue, the geometry of burner hearth is cylindrical, square column type or abnormity.
3, a kind of use method of blaze insulating fluidized forge furnace as claimed in claim 1 or 2, it is characterized in that: the course of work is as follows:
The combustion air of fuel by burner and secondary air channel be in combustion chamber mixed combustion, and thermal-flame during burning and high-temperature flue gas be by combustion chamber and flue, indirect fluidized bed calcination stove burner hearth; Under the blower fan dynamic action, the high-temperature flue gas in the flue enters burner hearth from the passage of burner hearth bottom as fluidizing gas; The material that enters burner hearth from feed pipe forms fluidization with high temperature fluidized gas in burner hearth mixes, and makes high-temperature gas and material produce heat transfer, mass transfer efficiently; The material that calcining the is good ascension that makes progress is sent into the High Temperature Gas solid separator through the outlet connecting pipe road and is carried out gas solid separation, and hot gas is used for the material preheating, and thermal material crashes into the cooling discharger, through the laggard warehouse of supercooling discharger.
4, method as claimed in claim 3 is characterized in that: burner is automation control, and temperature can be regulated arbitrarily in 500 ℃ of-1300 ℃ of scopes in the stove, in the burner hearth temperature difference ± 5 ℃; This high-temperature flue gas is heated inside and outside making fluidized calcinator, and double heat time heating time, has fully effectively utilized the fuel liberated heat, thermal efficiency height, and make that the interior temperature of fluidized bed calcination stove burner hearth is even, stable.
5, method as claimed in claim 3 is characterized in that: described fluidizing gas, its speed are 0.1---6.0 meter per second scopes.
6, method as claimed in claim 3 is characterized in that: described fuel is combustion gas, fuel oil or coal dust
7, method as claimed in claim 3 is characterized in that: described material, and particle mean size is 0---5000 micrometer ranges.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200410098988 CN1281912C (en) | 2004-12-23 | 2004-12-23 | Blaze insulating fluidized forge furnace |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200410098988 CN1281912C (en) | 2004-12-23 | 2004-12-23 | Blaze insulating fluidized forge furnace |
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|---|---|
| CN1631573A CN1631573A (en) | 2005-06-29 |
| CN1281912C true CN1281912C (en) | 2006-10-25 |
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| CN 200410098988 Expired - Fee Related CN1281912C (en) | 2004-12-23 | 2004-12-23 | Blaze insulating fluidized forge furnace |
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Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102320817A (en) * | 2011-08-15 | 2012-01-18 | 南京西普水泥工程集团有限公司 | Coal-gangue decarburizing system |
| CN106482518B (en) * | 2016-11-29 | 2019-05-10 | 德米特（苏州）电子环保材料有限公司 | Ablation device |
| CN106482519B (en) * | 2016-11-29 | 2019-05-31 | 德米特（苏州）电子环保材料有限公司 | Calcining furnace |
| CN106440798B (en) * | 2016-11-29 | 2019-05-31 | 德米特（苏州）电子环保材料有限公司 | Calciner |
| CN107555178A (en) * | 2017-10-10 | 2018-01-09 | 安徽科达洁能股份有限公司 | A kind of powder conveying apparatus and its application |
| CN108264248B (en) * | 2018-04-18 | 2023-07-18 | 镇江苏博特新材料有限公司 | Suspension calcination production process and device for light burned MgO |
| CN108483950A (en) * | 2018-04-18 | 2018-09-04 | 镇江苏博特新材料有限公司 | A kind of high activity MgO roasting techniques and its dedicated unit |
| CN112250323B (en) * | 2020-10-14 | 2022-07-01 | 沈阳化工大学 | Method for preparing sintered magnesia from powdery magnesite by one-step method |
| CN112250324B (en) * | 2020-10-14 | 2022-08-12 | 沈阳化工大学 | Method for preparing sintered magnesia from powdery magnesite by two-step method |
| CN115011187B (en) * | 2022-06-25 | 2023-04-18 | 科控环保材料(韶关)有限公司 | Preparation method of high-performance modified water-based paint |
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