CN1800762A - Hot-air furnace combined by combustion chamber and dustproof multi-stage heat exchanger with burning-resistant device - Google Patents

Hot-air furnace combined by combustion chamber and dustproof multi-stage heat exchanger with burning-resistant device Download PDF

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Publication number
CN1800762A
CN1800762A CN 200610018117 CN200610018117A CN1800762A CN 1800762 A CN1800762 A CN 1800762A CN 200610018117 CN200610018117 CN 200610018117 CN 200610018117 A CN200610018117 A CN 200610018117A CN 1800762 A CN1800762 A CN 1800762A
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CN
China
Prior art keywords
heat exchanger
hot
air
burning
blast
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Pending
Application number
CN 200610018117
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Chinese (zh)
Inventor
李开发
王卫明
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NANJING MAPLE KING STARCH EQUIPMENT CO Ltd
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NANJING MAPLE KING STARCH EQUIPMENT CO Ltd
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Application filed by NANJING MAPLE KING STARCH EQUIPMENT CO Ltd filed Critical NANJING MAPLE KING STARCH EQUIPMENT CO Ltd
Priority to CN 200610018117 priority Critical patent/CN1800762A/en
Publication of CN1800762A publication Critical patent/CN1800762A/en
Pending legal-status Critical Current

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Abstract

The invention relates to a combined wind heater with an anti-burn device and the functions of multi-step heat exchange and de-dust, which is formed by a burning room and a heat exchange. The heat exchanger comprises a horizontal multi-step heat exchange, whose tubes are vertically downwards arranged, and the tube plane at the upper end of first heat exchanger has an anti-burn anti-corrosion device; a safety gate is arranged at the front of heat exchanger integration; the cold wind via the fan from the tail to first heat exchanger is transformed into horizontal hot wind; the high-temperature smoke via the first heat exchanger from up-to-down and via the multi-step heat exchanger pip is discharged via wind outlet. The invention can save 65% coal energy than steam boiler and save 30% coal energy than the heat conductive oil furnace, while it has lower maintenance cost, quick temperature increase, quick stop, and automatic control, while its temperature adjusting range is between 100-350Deg. C and the recycle rate of hot wind is between 85-95%.

Description

But combustion chamber and the hot-air furnace combined of burning-resistant device, multi-stage heat exchanger dedusting arranged
Technical field
The present invention relates to a kind of hot-blast furnace equipment, especially a kind of suitable to dry with hot blast various products, with the supporting hot-blast stove of multiple drying plant.
Background technology
In the various industrial and agricultural productions, be mostly steam boiler and heat conducting oil boiler, by the radiator indirect heat exchange, hot blast is provided so long as carry out dry employed hot blast main source with hot blast.This indirect heat exchange boiler efficiency is low, complicated, technical security content height.Another is energy-conservation, be exactly with combustion gas, coal, scoot etc. easily, directly burning in the heat exchange body, air changes the warm-air supply drying plant into and uses in heat pipe.The long-term use of safety that how to guarantee this calandria (stove) is the previous the most key technical big problem of order, pipe outer makes a fire simultaneously, intraductal heat exchange wind all is unscientific, strengthen management howsoever and keep the safety in production, all be pain in the neck feelings the most, mainly be not durable, leak cigarette, leak fire, the life-span is not long.
Summary of the invention
The purpose of this invention is to provide that a kind of thermal loss is little, dust removing effects is remarkable from designing and producing the safety that has guaranteed heat exchanger, it is again multistage dedusting simultaneously that multi-stage heat exchanger is arranged, and the rate of recovery of hot blast is 85%~95%, energy-conservation, practical combined hot-blast stove.
The technical solution used in the present invention is:
Form by combustion chamber and heat exchanger assembly.Be horizontally disposed with multi-stage heat exchanger in the heat exchanger assembly, the tubulation in the heat exchanger is arranged vertically downward, is provided with the wear-resistant device of anti-the burning on tubulation plane, first heat exchanger upper end, at heat exchanger assembly front end safety gate is set.The temperature difference heat exchange mode of hot-blast stove is: cold wind is discharged hot blast by afterbody to first order heat exchanger through the blower level straight line, high-temperature flue gas from first heat exchanger from top to down, through the multi-stage heat exchanger walking in pipe, discharge air-vent at last.
The described wear-resistant device of anti-the burning is that stuffy place is filled and led up with the insulation baking proof material at the tube head of one section same diameter of each mouth of pipe place spot welding of heat exchanger tube air inlet.Safety gate is square three interlock gates, and flashboard is arranged on main air duct, the connecting rod of ining succession on the flashboard, and two pull bars are adorned at connecting rod top dress jacking equipment, middle part, and pull bar one headband has two interlock doors.This heat exchanger assembly is made up of secondary or multi-stage heat exchanger, and hot blast adopts secondary, 150~200 ℃ of employings to adopt more than the Pyatyis for three grades, 250~350 ℃ at 100 ℃.
Specifically, exactly the hot-blast stove of existing disjunctor hot-blast stove and directly burning type has been carried out many-sided improvement:
(1) combustion chamber and heat exchanger are separated, the combustion chamber is the high heat insulation effect that the performance requirement of based on fuel is manufactured, can air blast be arranged clean-burning combustion chamber (burner), Fig. 1 is seen in blast pipe, fire grate fire door, slag-drip opening, heavy grey dedusting mouth, high-temperature flue gas outlet.
(2) the heat exchanger assembly is made up of secondary or multi-stage heat-exchanger, high-temperature flue gas import, heat exchanger, security exhaust door, shutter, dedusting ash-draining gate, cold wind air inlet (being provided with air blast), hot blast flue dust air inducing outlet (outlet is provided with water dedusting and air-introduced machine), exchange hot-blast outlet and safety gate are arranged, see Fig. 1.
(3) the heat exchanger first order also is that the high temperature interchanger has burning-resistant device, has guaranteed the service life of interchanger.
(4) interchanger tubulations at different levels are arranged verticals, utilize whirlwind sedimentation principle to reclaim dust automatically, have formed multistage dust removing effects.
(5) heat exchangers at different levels are provided with shutter and go out air door at the high-temperature flue gas passage, under urgent situation, open air door, guarantee not hyperthermia and superheating of heat exchanger, accomplish safe and reliable.
(6) air blast is equipped with in the import of heat exchanger assembly cold air, and the hot blast air outlet is equipped with safety gate, as long as dry when not wanting hot blast, closes the tail gates hot blast and discharges, and cold wind enters oven dry simultaneously.
(7) main is that heat exchange mode has changed, and is the new method of logical high-temperature flue gas, heat transfer outside a tube in the pipe, and heat exchanger can be made with stainless steel material and high temperature resistant steel and two kinds of materials of tubing.
Through trying out in tapioca factory, act as a fuel with coal, steam oven, hot-blast stove, the employed coal of heat-conducting oil furnace all are the coals with a kind of caloric value, the starch of oven dry is under same temperature, employed dryer also is with the same negative pressure one-level drying plant, briefly, is exactly that experimental condition is the same, the effect of using is different, as shown in the table.
3 Starch coal (Kg) 160Kg 100kg 70Kg
4 Per hour produce starch 4.5 ton 4.5 ton 4.5 ton
5 Processing mode in emergency circumstances Hypertonia, the discharging steam, when not having electricity, the easy lack of water of boiler. Conduction oil heats up too high, the oil flow is slow, and is unfavorable to service life. Close the hot-blast outlet gate, open all safety door air doors and go out slag.
6 Method for safe operation and processing mode Multiple security monitoring and treatment process, complexity, be awkward. Multiple security monitoring and have strict fire prevention measure, complexity to be awkward. Turn off air-introduced machine and open safety door, simple to operate as long as temperature raises to report to the police.
7 The operating maintenance maintenance Complicated, workload is big, cost is high. Complicated, workload is big, cost is high. Simply, workload is little, cost is low.
8 Studio environment and dust treatment Studio environment, stove external environment flue dust are bigger, simultaneously the dust treatment complexity, water consumption is big, cost is high. Studio environment, stove external environment flue dust are bigger, and the complicated water consumption of dust treatment is big simultaneously, cost is high. 80 percent flue dust reclaims at the heat exchanger place, exhaust-gas treatment is simple, water is few, operating room's negative pressure state clean environment.
Advantage and good effect thereof:
Hot-blast stove of the present invention is energy-conservation, safe, durable, environmental protection, than steam boiler (energy) 65% of economizing on coal, than heat-conducting oil furnace (energy) 30% of economizing on coal, simultaneously it still is that a kind of operation expense is low, intensification, blowing out be the fastest, in emergency circumstances preferably handle, control simple equipment automatically, can design the hot-blast stove of all size specification according to customer requirements, the temperature adjustable extent of hot-blast stove is between 100 ℃~350 ℃, the rate of recovery of hot blast is 85~95%, and energy-saving effect is remarkable.
Description of drawings
Fig. 1 is a hot-blast stove structural representation of the present invention.
Fig. 2 is the front view of Fig. 1 Combustion of Hot Air Furnace chamber.
Fig. 3 is the cutaway view of Fig. 1 combustion chamber.
Fig. 4 is Fig. 1 heat exchanger assembly front view.
Fig. 5 is Fig. 1 heat exchanger assembly cutaway view.
Fig. 6 is a hot-blast outlet safety gate structural representation.
Indicate among the figure: combustion chamber 1, heat exchanger assembly 2, air blast 3, hot-blast outlet 4, safety gate 5, cold wind import 6, big air blast 7, clean room 8, dedusting and air inducing 9, ash gate 10, fire door 11, combustion chamber Steel bar rack 12, heavy grey chamber ash-draining gate 13, combustion chamber blast pipe 14, burner hearth 15, fire grate 16, high-temperature flue gas outlet portal 17, heavy grey chamber 18, first heat exchanger 19, high-temperature flue gas exhaust door 20, second heat exchanger 21, exhaust gases passes shutter 22, exhaust gases passes goes out air door 23, the 3rd heat exchanger 24, the 4th heat exchanger 25, exhaust gases passes shutter 26, primary dust removing mouth and barricade 27, two-stage dust removal mouth and barricade 28, the first heat exchanger burning-resistant device 29, heat exchanger assembly and insulated wall 30, become windscreen wall 31 on the 3rd heat exchanger, flue dust tail wind outlet 32, safety gate device: flashboard 33, interactive Door lock with linakage locking bar 34, connecting rod 35, power set 36, pull bar 37, fixed support 38.
The specific embodiment
Hot-blast stove is made up of the two large divisions: first is combustion chamber (burner), the combustion chamber is according to the fuel that is provided, at the combustion chamber that is made into high insulation, this part is fuel combustion to be become high-temperature flue gas (500 ℃~1000 ℃) supply with second portion heat exchanger assembly.Second portion heat exchanger assembly is that the high-temperature flue gas that will burn converts 150 ℃~350 ℃ hot blasts to by heat exchange, can directly dry with the mixing of materials and the displacement of oven dry.The flue gas that lead to high-temperature flue gas in this heat exchanger process innovating reform, tubulation heat exchange, the pipe, burning-resistant device is arranged, physical life is long, multistage dedusting, smoke evacuation is arranged needs only simple process and reaches emission request fully; a plurality of safe ventilation doors are arranged; guarantee the safety of heat exchanger during power failure; after the displacement; tail cigarette Controllable Temperature has guaranteed energy-conservation effect built in below 80 ℃.
Combustion chamber 1 is the burner hearth that produces high-temperature flue gas, the front have the fire door 11 that feeds intake, burner hearth 15, in have fire grate 16, fire grate downside back to have air blast 3 and combustion chamber blast pipe 14, front that ash gate 10, heavy grey chamber 18, high-temperature flue gas outlet 17 are arranged.See Fig. 3.
Heat exchanger assembly 2 is by four heat exchangers 19; 21; 24; 25 form; horizontal linear is placed; the tubulation arranged vertical; hot-blast outlet 4 and safety gate 5 are arranged before first heat exchanger; afterbody has cold wind import 6 and big air blast 7; clean room 8; hot flue gas enters first heat exchanger 19 from 17 outlets of high-temperature flue gas outlet portal; be provided with burning-resistant device 29 on tubulation plane, first heat exchanger upper end; see Fig. 5; the shoe of anti-the burning is the tube head in one section same diameter of each mouth of pipe place spot welding of heat exchanger tube air inlet; above stuffy place fill and lead up with the insulation baking proof material; just formed the protective device of a special use; this device can repeat after impaired to change and the not burning heat exchanger tube also is provided with a hot flue gas ejection door 20 and barricade simultaneously.There is the elevated temperature heat exhaust gases passes to go out air door 23 at the second heat exchanger downside elevated temperature heat exhaust gases passes shutter 22, upside, also have a flue gas shutter 26 at the 4th heat exchanger downside flue place, the second, the 4th shutter downside is provided with primary dust removing mouth and barricade, two-stage dust removal mouth and barricade 27,28, also be provided with simultaneously the twice windbreak, the 3rd heat exchanger also has change windscreen wall 31 one to upside, is mainly used to change hot flue gas direction.Insulated wall 30 protections are all carried out except that being welded into steel plate the casing of full envelope in heat exchanger assembly periphery.
Safety gate 5 is three interlock gates of a square, at main air duct flashboard 33 is arranged, the flashboard upper end connecting rod 35 of ining succession, power set 36 are equipped with on connecting rod top, two pull bars 37 are equipped with at the connecting rod middle part, pull bar one headband has two interactive Door lock with linakage locking bar 34, and the linkage of emergency lock is interactive Door lock with linakage locking bar 34, connecting rod 35, power set 36, pull bar 37 is fixed on the fixed support 38 and warm-air pipe outlet oven dry pipe two ends.
Operation principle:
1., fuel (coal) is lighted in combustion chamber 1 after, sufficient oxygen is arranged under the effect of air blast and air inducing, guaranteed the completing combustion of fuel in burner hearth 15, produced enough high-temperature flue gas, through heavy grey chamber 18, by high-temperature flue gas outlet portal 17, enter the heat exchanger assembly.In this process, the hot blast temperature that can provide according to oven dry is again through the fire door coal, close down with air inducing and adjust required temperature (automatically and manually), in normal operation, air blast can, thereby guaranteed the supply of high-temperature flue gas.
2., heat exchanger assembly 2 is that the high-temperature flue gas that the combustion chamber provides is changed into the used hot blast of drying plant that designs, transfer process is finished in two sub-sections: the course of work of high-temperature flue gas and hot blast conversion work process.
A. high-temperature flue gas enters the first heat exchanger upper inlet through high-temperature flue gas outlet portal 17; burning-resistant device 29 is equipped with at 19 upper inlet places at first heat exchanger; the highest temperature flue gas that is used for protecting heat exchanger to begin does not directly burn the weld of heat exchanger plain furnaces pipe and high temperature plate; and can not produce damage; have only first heat exchanger to be subjected to the influence of the highest temperature; other grades are all lowered the temperature in the process of heat exchange, and can not damage.The (see figure 5) flue gas is according to designing the route walking; walk downwards through first heat exchanger; laterally enter the second heat exchanger lower flue and be subjected to the barricade effect; this moment, flue dust fell into primary dust removing device and barricade 27 places; high-temperature flue gas returns upwards walking; laterally be subjected to the 3rd heat exchanger barricade effect again; return downward walking; through the upwards walking of the 4th heat exchanger downside; flue dust falls into secondary ash collector and barricade 28 places again, is exported 32 suction dedusters and air-introduced machine is discharged in the air by air-introduced machine through flue dust tail wind at last, and a plurality of safe inlet/outlets and dedusting mouth are arranged in the lower channel on flue; guaranteed that flue gas in case of emergency can reduce channel temperature by advancing emptying gas, protection heat exchanger safety.The supply of high-temperature flue gas is that to act in the whole flue through air inducing be negative pressure work, and does not lose heat energy.
B. the conversion of hot blast: be that the heat exchange mode natural air that designs by Fig. 5 in the heat exchanger assembly enters heat exchanger assembly air inlet through clean air compartment 8 under big air blast 7 air blast, from the 4th heat exchanger 25 to first heat exchanger, 19 direction straight line bottom horizontal flow sheet, be subjected in the front multi-stage heat exchanger vertically the heat exchanger tube of product word arrangement stop, air is through the friction of each tubulation, carried out heat exchange, cold air is by cold heating, finish the hot blast conversion that designs, about the tubulation, both sides all are the hot blast heat exchanger channels by steel plate welding formation sealing, guaranteeing heat exchange, is positive pressure air in this passage, outwards exhaust, not having flue gas enters, so hot gas is environmental protection, safety, hot blast enters safety gate control through outlet, can provide hot blast to drying system fully when oven dry.Emergency lock can be controlled automatically and manually, when opening a sluice gate plate to the oven dry hot wind supply, two upper side cover can be closed down simultaneously, are dried the effect of air inducing, in the convection current in a basic balance of emergency lock place positive and negative pressure air quantity.Work as emergency, close upper flashboard, two upper side cover are driven by connecting rod, open automatically, and hot blast is discharged in the air, and cold wind enters in the drying system.
At whole hot-blast stove, the total Chengdu of combustion chamber and heat exchanger requires to be incubated with the high-quality insulation material, is effective well, and the combustion chamber high temperature flue gas all is that the thermal source of working under negative pressure does not run off.And hot blast is in basic direct draught work; can not advance dust; shutting down or in emergency circumstances; open all safety-valves, see Fig. 4, coal fire cleaning in the combustion chamber; the hot blast safety gate is closed down and opens exhaust gases passes air-out and shutter; heat exchanger just can not burn out, and the safety of this hot-blast stove has been subjected to protection, has accomplished that safety provides the cleaning hot blast.By multistage heat-exchange dedusting, add the environment protection emission flue gas quality that the water mill dedusting has guaranteed hot-blast stove.

Claims (5)

  1. But 1, a kind of combustion chamber and the hot-air furnace combined of burning-resistant device, multi-stage heat exchanger dedusting arranged, comprise combustion chamber and heat exchanger assembly, it is characterized in that: be horizontally disposed with multi-stage heat exchanger (19), (21), (24), (25) in the heat exchanger assembly (2), tubulation in the heat exchanger is arranged vertically downward, be provided with the wear-resistant device of anti-burning the (20) on tubulation plane, first heat exchanger (19) upper end, safety gate (5) be set at heat exchanger assembly (2) front end.
  2. 2, according to claim 1 hot-air furnace combined, the temperature difference heat exchange mode that it is characterized in that hot-blast stove is: cold wind is discharged hot blast by afterbody to first order heat exchanger through the blower level straight line, high-temperature flue gas from first heat exchanger from top to down, through the multi-stage heat exchanger walking in pipe, discharge air-vent at last.
  3. 3, according to claim 1 hot-air furnace combined, it is characterized in that: the described wear-resistant device of anti-burning the (20) is that stuffy place is filled and led up with the insulation baking proof material at the tube head of one section same diameter of each mouth of pipe place spot welding of heat exchanger tube air inlet.
  4. 4, according to claim 1 hot-air furnace combined, it is characterized in that: safety gate (5) is square three interlock gates, flashboard (34) is arranged on main air duct, the flashboard upper end connecting rod (37) of ining succession, two pull bars (35) are adorned at connecting rod (37) top dress jacking equipment (36), middle part, and pull bar one headband has two interlock doors (34).
  5. 5, according to claim 1 hot-air furnace combined, it is characterized in that: this heat exchanger assembly (2) is made up of secondary or multi-stage heat exchanger, and hot blast adopts secondary, 150~200 ℃ of employings to adopt more than the Pyatyis for three grades, 250~350 ℃ at 100 ℃.
CN 200610018117 2006-01-05 2006-01-05 Hot-air furnace combined by combustion chamber and dustproof multi-stage heat exchanger with burning-resistant device Pending CN1800762A (en)

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Application Number Priority Date Filing Date Title
CN 200610018117 CN1800762A (en) 2006-01-05 2006-01-05 Hot-air furnace combined by combustion chamber and dustproof multi-stage heat exchanger with burning-resistant device

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Application Number Priority Date Filing Date Title
CN 200610018117 CN1800762A (en) 2006-01-05 2006-01-05 Hot-air furnace combined by combustion chamber and dustproof multi-stage heat exchanger with burning-resistant device

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Publication Number Publication Date
CN1800762A true CN1800762A (en) 2006-07-12

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102213541A (en) * 2011-05-26 2011-10-12 天津华能北方热力设备有限公司 Coal hot air furnace capable of simultaneously generating steam
CN103175296A (en) * 2011-12-26 2013-06-26 谢振斌 Three-level conduction boiler
CN105423735A (en) * 2015-12-25 2016-03-23 安吉中瑞膨润土化工有限公司 Energy-saving environment-friendly heating plant for drying bentonite
CN105841348A (en) * 2016-05-31 2016-08-10 贵州大学 Adjustable combined heat exchanger air heating furnace and working method thereof

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102213541A (en) * 2011-05-26 2011-10-12 天津华能北方热力设备有限公司 Coal hot air furnace capable of simultaneously generating steam
CN103175296A (en) * 2011-12-26 2013-06-26 谢振斌 Three-level conduction boiler
CN103175296B (en) * 2011-12-26 2015-08-19 谢振斌 Three grades of conduction boiler
CN105423735A (en) * 2015-12-25 2016-03-23 安吉中瑞膨润土化工有限公司 Energy-saving environment-friendly heating plant for drying bentonite
CN105423735B (en) * 2015-12-25 2017-11-17 安吉中瑞膨润土化工有限公司 A kind of bentonite drying heating plant of energy-conserving and environment-protective
CN105841348A (en) * 2016-05-31 2016-08-10 贵州大学 Adjustable combined heat exchanger air heating furnace and working method thereof

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