CN104654266A - Water boiler with single boiler barrel and four return strokes - Google Patents

Water boiler with single boiler barrel and four return strokes Download PDF

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Publication number
CN104654266A
CN104654266A CN201510064136.3A CN201510064136A CN104654266A CN 104654266 A CN104654266 A CN 104654266A CN 201510064136 A CN201510064136 A CN 201510064136A CN 104654266 A CN104654266 A CN 104654266A
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CN
China
Prior art keywords
flue
drum
backhaul
threaded
tube
Prior art date
Application number
CN201510064136.3A
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Chinese (zh)
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CN104654266B (en
Inventor
何崇锋
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昌图县锅炉制造厂
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Priority to CN201510064136.3A priority Critical patent/CN104654266B/en
Publication of CN104654266A publication Critical patent/CN104654266A/en
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00Combustion technologies with mitigation potential
    • Y02E20/30Technologies for a more efficient combustion or heat usage

Abstract

The invention discloses a water boiler with a single boiler barrel and four return strokes. The boiler comprises a furnace body, wherein a pot body is arranged in the furnace body, the pot body comprises a longitudinal boiler barrel, a left header, a right header, a descending pipe and a water wall tube group, the water wall tube group is formed by an inner side heat exchange tube group, a middle heat exchange tube group and an outer side heat exchange tube group, a threaded flue tube group is arranged in the boiler barrel, the threaded flue tube group in the boiler barrel is formed by an upper threaded flue tube group and a lower threaded flue tube group, after high-temperature flue gas generated by combustion of fuel in a hearth is subjected to heat exchange of four returns strokes in the furnace body in sequence, the high-temperature flue gas is discharged out of the furnace body. The water boiler with the single boiler barrel and the four return strokes has the advantages of long heat exchange stroke of the high-temperature flue gas and the water in the pot body, thorough heat exchange, low flue gas discharge temperature, thorough fuel combustion and low blackness level of the discharged flue gas.

Description

A kind of single drum four pass hot water boiler

Technical field

The present invention relates to a kind of hot-water boiler, especially a kind of single drum longitudinal smoke-fire-tube hot-water boiler.

Background technology

Single drum longitudinal smoke-fire-tube hot-water boiler is a kind of common hot-water boiler, single drum longitudinal smoke-fire-tube hot-water boiler of the prior art adopts three backhaul designs usually, namely the first backhaul is burner hearth face arch trailing edge to rear wall section by interior side water wall tube group, the determined flue in drum bottom surface, second backhaul is left wing's shape flue and the right flank shape flue of drum side-lower, 3rd backhaul is drum internal thread smoke pipe group flue, and the high-temperature flue gas that fuel combustion produces discharges body of heater successively after three backhaul heat exchange.There is following shortcoming in the boiler of this structure: one is that high-temperature flue gas stroke of heat exchange in body of heater is shorter, and be unfavorable for flue gas and the abundant heat exchange of water, smog discharge temperature is high, and energy loss is many; Two is that the combustible particles combust carried secretly in high-temperature flue gas is not thorough, unburnt burnable granule is together discharged with flue gas, fuel availability is low, and containing the flue gas meeting contaminated air of unburnt burnable granule, need to arrange special dust arrester, just can reach discharge standard, add the environmental protection cost of boiler; Three is that the partial particulate carried secretly in flue gas can sedimentation in wing flue and threaded flue, needs to carry out ash disposal cleaning every 2-3 weeks, affects the effective run time of boiler.

In addition, during common three backhaul list drum longitudinal smoke-fire-tube hot-water boiler work, high-temperature flue gas only has a backhaul heat exchange at drum, therefore heat exchange is not thorough, smog discharge temperature is higher, and due to no third backhaul air-supply arrangement, the burnable granule in flue gas is caused to burn not thorough, fuel availability is not high, the flue gas blackness grade discharged is high, just discharge standard can be reached after needing special fume dust remover process, and, this boiler only can select the fuel of more than two class bituminous coal (containing two class bituminous coal), and be not suitable for selection one class bituminous coal, the smuts such as brown coal.

Summary of the invention

The technical problem that invention will solve is: provide a kind of single drum four pass hot water boiler, water heat exchange stroke in this single drum four pass hot water boiler high-temperature flue gas and pot body is long, and heat exchange is thorough, and smog discharge temperature is low, fuel combustion is thorough, and the flue gas blackness grade of discharging is low.

The technical scheme that technical solution problem is taked: a kind of single drum four pass hot water boiler, comprise body of heater, a pot body is provided with in body of heater, described pot body comprises the drum of longitudinal, left header, right header, down-comer and water screen tube group, described water screen tube group is by inner side set of heat exchange tubes, intermediate heat transfer pipe group and outside set of heat exchange tubes are formed, threaded flue group is provided with in drum, threaded flue group in drum is made up of upper threaded flue group and lower threaded flue group, the high-temperature flue gas that fuel produces in burner hearth combustion discharging body of heater successively in body of heater after four backhaul heat exchange, first backhaul is burner hearth face arch trailing edge to rear wall section by interior side water wall tube group, the determined flue in drum bottom surface, second backhaul is left wing's shape flue and the right flank shape flue of drum side-lower, 3rd backhaul is the lower threaded flue group flue in drum, 4th backhaul is the upper threaded flue group flue in drum, the smokestack making the first backhaul flue gas enter the wing flue of the second backhaul is provided with in both sides, burner hearth rear portion, lower flue before front tube sheet place is provided with the wing flue outlet of connection and lower threaded flue group flue entrance, the rear revolution smoke box of threaded flue group flue outlet and upper threaded flue group flue entrance under back tube sheet place is provided with connection, upper smoke box before threaded flue group flue outlet and fume emission mouth is provided with in connection above front lower smoke box, the 3rd backhaul ajutage into high-temperature flue gas supplemental oxygen is provided with in front lower smoke box.

As improvement of the present invention: be also provided with the analytical sampling pipe gathering high-temperature flue gas sample in front lower smoke box.

As a further improvement on the present invention: in left wing's shape flue, right flank shape flue, be respectively provided with the second backhaul ajutage into high-temperature flue gas supplemental oxygen.

As another improvement of the present invention: intermediate heat transfer pipe group heat exchanger tube upper exposed is in the middle part of wing flue, and bottom exposed is in burner hearth.

Improve as another kind of the present invention: inner side set of heat exchange tubes is made up of staggered wall heat exchanger tube and furnace chamber heat exchange tube.

Beneficial effect: single drum four pass hot water boiler of the present invention, because the threaded flue group that have employed in drum is made up of upper threaded flue group and lower threaded flue group, the high-temperature flue gas that fuel produces in burner hearth combustion discharging body of heater successively in body of heater after four backhaul heat exchange, first backhaul is burner hearth face arch trailing edge to rear wall section by interior side water wall tube group, the determined flue in drum bottom surface, second backhaul is left wing's shape flue and the right flank shape flue of drum side-lower, 3rd backhaul is the lower threaded flue group flue in drum, 4th backhaul is the upper threaded flue group flue in drum, the smokestack making the first backhaul flue gas enter the wing flue of the second backhaul is provided with in both sides, burner hearth rear portion, lower smoke box before front tube sheet place is provided with the wing flue outlet of connection and lower threaded flue group flue entrance, the rear revolution smoke box of threaded flue group flue outlet and upper threaded flue group flue entrance under back tube sheet place is provided with connection, upper smoke box before threaded flue group flue outlet and fume emission mouth is provided with in connection above front lower smoke box, the technical characteristic of the 3rd backhaul ajutage into high-temperature flue gas supplemental oxygen is provided with in front lower smoke box, more common single drum longitudinal smoke-fire-tube hot-water boiler adds a threaded flue heat exchange backhaul, extend the stroke of the water heat exchange in high-temperature flue gas and pot body, make the water heat exchange in high-temperature flue gas and pot body more abundant, reduce the exhaust temperature of flue gas, decrease heat-energy losses, adopt simultaneously and be provided with as the 3rd backhaul ajutage of high-temperature flue gas supplemental oxygen is for entering the high-temperature flue gas supplemental oxygen of the 3rd backhaul in front lower smoke box, on the one hand the unburnt combustible granules of carrying secretly in high-temperature flue gas is burnt away in threaded flue, until after-flame, improve the fuel availability of boiler, reduce the blackness levels of discharge flue gas, flue gas flow rate can be drawn high on the other hand, prevent the high-temperature flue gas caused owing to increasing a backhaul from passing through apart from long in threaded flue, particle in flue gas is stall settlement influence heat transfer effect in spiral smoke pipe.Owing to have employed the technical characteristic being also provided with the analytical sampling pipe gathering high-temperature flue gas sample in front lower smoke box, sample analysis can be carried out to the high-temperature flue gas in front lower smoke box in real time by analytical sampling pipe, and according to the air output of analysis result adjusting and optimizing the 3rd backhaul ajutage, make the duty that boiler keeps best, prevent that air output is excessive causes flue-gas temperature to decline and flue gas flow rate is too fast, heat exchange is not thorough on the one hand; Prevent the too small oxygen that necessity can not be provided for the uncombusted combustible granules of carrying secretly in flue gas of air output on the other hand.Owing to have employed on a left side, the technical characteristic of the second backhaul ajutage into high-temperature flue gas supplemental oxygen is provided with in right flank shape flue, the fuel gas of the cigarette after-flame carried secretly in high-temperature flue gas and particle are burnt away in wing flue, and the particle be deposited in wing flue can be blown afloat, make it burn or together enter next backhaul with high-temperature flue gas, final discharge body of heater, therefore, not only increase the utilization rate of fuel, and extend the ash disposal cycle of wing flue, the wing flue of single drum four pass hot water boiler of the present invention and the ash disposal cycle of threaded flue are 3 months, and the ash disposal cycle of common single drum wing flue of longitudinal smoke-fire-tube hot-water boiler and threaded flue is 2-3 week, not only reduce the maintenance cost of boiler, and improve the effective time of boiler.Owing to have employed intermediate heat transfer pipe group heat exchanger tube upper exposed in the middle part of wing flue, the technical characteristic of bottom exposed in burner hearth, make that intermediate heat transfer pipe top fully can contact with the high-temperature flue gas in wing flue, heat exchange, and flow-disturbing is carried out to the high-temperature flue gas in wing flue, the air supplemented into is fully mixed, for flammable thing is combustion-supporting, simultaneously with high-temperature flue gas, high-temperature flue gas forms turbulent flow and advances in wing flue, and heat transfer effect is better.Owing to have employed the technical characteristic that inner side set of heat exchange tubes is made up of staggered wall heat exchanger tube and furnace chamber heat exchange tube, make furnace chamber heat exchange tube full angle and thermal-flame or smoke contacts, be combined to form three-dimensional set of heat exchange tubes with wall heat exchanger tube, further increase the efficiency of boiler.Single drum four pass hot water boiler of the present invention can select two class bituminous coal, a class bituminous coal or brown coal to be fuel, can reach the discharge standard that GB3271-2014 specifies when using a class bituminous coal or brown coal without the need to increasing special soot processing device.

Accompanying drawing explanation

Fig. 1 is that single drum four pass hot water boiler of the present invention is along drum axial section structural representation;

Fig. 2 is that single drum four pass hot water boiler of the present invention partly cuts open structural representation along drum radial direction.

Detailed description of the invention

Below in conjunction with accompanying drawing, single drum four pass hot water boiler of the present invention is described in further detail.

As shown in Figure 1 and Figure 2, single drum four pass hot water boiler of the present invention is made up of body of heater and metal pan two large divisions, body of heater comprises the structures such as furnace wall, fire grate 8, coal bunker 7, air compartment 9, face arch 6, rear arch 17, pot body is arranged in body of heater, described pot body comprises longitudinal drum 12, left header 26, right header, down-comer and water screen tube group, in drum, be provided with water recovery apparatus 10, discharging device 11, water replanishing device 18, drum is also provided with the auxiliary equipments such as safety valve, manhole, hand hole.

As shown in Figure 2, described water screen tube group is made up of inner side set of heat exchange tubes, intermediate heat transfer pipe group and outside set of heat exchange tubes, intermediate heat transfer pipe group heat exchanger tube 24 upper exposed is in the middle part of wing flue, bottom exposed is in burner hearth, inner side set of heat exchange tubes is made up of staggered many endwalls face heat exchanger tube 23 and Duo Gen furnace chamber heat exchange tube 25, outside set of heat exchange tubes is made up of the many outside heat exchanger tubes 20 pasting furnace wall setting, in drum, be provided with threaded flue group, the threaded flue group in drum is made up of upper threaded flue group 14 and lower threaded flue group 13.

The high-temperature flue gas that fuel produces in burner hearth combustion discharging body of heater successively in body of heater after four backhaul heat exchange, first backhaul I is burner hearth face arch trailing edge to 19 sections, rear wall by interior side water wall tube group, the determined flue in drum bottom surface, second backhaul II is left wing's shape flue 21 and the right flank shape flue of drum side-lower, 3rd backhaul III is the lower threaded flue group flue in drum, 4th backhaul IV is the upper threaded flue group flue in drum, the smokestack 16 making the first backhaul flue gas enter the wing flue of the second backhaul is provided with in both sides, burner hearth rear portion, lower smoke box 4 before front tube sheet place is provided with the wing flue outlet of connection and lower threaded flue group flue entrance, the rear revolution smoke box 15 of threaded flue group flue outlet and upper threaded flue group flue entrance under back tube sheet place is provided with connection, upper smoke box 2 before threaded flue group flue outlet and fume emission mouth 1 is provided with in connection above front lower smoke box, the 3rd backhaul ajutage 5 into high-temperature flue gas supplemental oxygen and the sample analysis pipe 3 gathering high-temperature flue gas sample is provided with in front lower smoke box, at left wing's shape flue, the second backhaul ajutage 22 into high-temperature flue gas supplemental oxygen is respectively provided with in right flank shape flue.

Single drum four pass hot water boiler of the present invention is the high-temperature flue gas supplemental oxygen entering threaded flue by arranging the 3rd backhaul ajutage, promote that uncombusted particle burns away in the 3rd backhaul, until thorough after-flame, therefore, single drum four pass hot water boiler of the present invention can select two class bituminous coal, a class bituminous coal or brown coal as fuel, when employing one class bituminous coal or brown coal are as fuel, particle in flue gas all can thoroughly burn, without the need to increasing special fume dust remover, the discharge standard of national regulation just can be reached.Air-supply due to the 3rd backhaul ajutage accelerates the flow velocity of flue gas in threaded flue, avoid particle sedimentation in threaded flue of carrying secretly in flue gas and form dust stratification, but, the too fast contracting of flue gas flow rate is by the time of short high-temperature flue gas heat exchange in threaded flue, cause flue gas heat exchange insufficient, therefore, present invention employs four backhaul designs, threaded flue in drum is divided into upper threaded flue group and lower threaded flue group, make high-temperature flue gas in drum, experience two backhaul heat exchange, add flue gas stroke, overcome flue gas flow rate too fast and be unfavorable for the drawback of heat exchange.

The air entering the second backhaul ajutage and the 3rd backhaul ajutage through the pre-heat treatment, should can be avoided Cryogenic air to enter flue and absorb flue gas heat, reduction flue-gas temperature like this.The mode of preheating can, by arranging air preheater at boiler smoke floss hole, also can adopt alternate manner to carry out preheating to the air entering the second backhaul ajutage and the 3rd backhaul ajutage.

Table 1 is common single drum longitudinal smoke-fire-tube hot-water boiler performance indications correction data of single drum four pass hot water boiler of the present invention and same model.

Table 1

Claims (5)

1. single drum four pass hot water boiler, comprise body of heater, a pot body is provided with in body of heater, described pot body comprises the drum of longitudinal, left header, right header, down-comer and water screen tube group, it is characterized in that: described water screen tube group is by inner side set of heat exchange tubes, intermediate heat transfer pipe group and outside set of heat exchange tubes are formed, threaded flue group is provided with in drum, threaded flue group in drum is made up of upper threaded flue group and lower threaded flue group, the high-temperature flue gas that fuel produces in burner hearth combustion discharging body of heater successively in body of heater after four backhaul heat exchange, first backhaul is burner hearth face arch trailing edge to rear wall section by interior side water wall tube group, the determined flue in drum bottom surface, second backhaul is left wing's shape flue and the right flank shape flue of drum side-lower, 3rd backhaul is the lower threaded flue group flue in drum, 4th backhaul is the upper threaded flue group flue in drum, the smokestack making the first backhaul flue gas enter the wing flue of the second backhaul is provided with in both sides, burner hearth rear portion, lower flue before front tube sheet place is provided with the wing flue outlet of connection and lower threaded flue group flue entrance, the rear revolution smoke box of threaded flue group flue outlet and upper threaded flue group flue entrance under back tube sheet place is provided with connection, upper smoke box before threaded flue group flue outlet and fume emission mouth is provided with in connection above front lower smoke box, the 3rd backhaul ajutage into high-temperature flue gas supplemental oxygen is provided with in front lower smoke box.
2. single drum four pass hot water boiler according to claim 1, is characterized in that: in front lower smoke box, be also provided with the analytical sampling pipe gathering high-temperature flue gas sample.
3. single drum four pass hot water boiler according to claim 1 and 2, is characterized in that: in left wing's shape flue, right flank shape flue, be respectively provided with the second backhaul ajutage into high-temperature flue gas supplemental oxygen.
4. single drum four pass hot water boiler according to claim 3, is characterized in that: intermediate heat transfer pipe group heat exchanger tube upper exposed is in the middle part of wing flue, and bottom exposed is in burner hearth.
5. single drum four pass hot water boiler according to claim 4, is characterized in that: inner side set of heat exchange tubes is made up of staggered wall heat exchanger tube and furnace chamber heat exchange tube.
CN201510064136.3A 2015-02-09 2015-02-09 Water boiler with single boiler barrel and four return strokes CN104654266B (en)

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CN201510064136.3A CN104654266B (en) 2015-02-09 2015-02-09 Water boiler with single boiler barrel and four return strokes

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CN104654266B CN104654266B (en) 2017-02-22

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104848191A (en) * 2015-06-03 2015-08-19 陈小喜 Improved single-drum horizontal type coal-fired steam boiler

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB175737A (en) * 1920-11-18 1922-02-20 William Thomas Bell Improved construction of gas fired multitubular boiler
CN2033481U (en) * 1988-06-08 1989-03-01 大连轻工机械总厂 Water and smoke-tube boiler
CN2104409U (en) * 1991-06-10 1992-05-13 沈阳前进锅炉厂 Single-tube longitudinal shell type water-heating boiler
CN2385270Y (en) * 1998-03-14 2000-06-28 郭保林 Four or five return non-pressure boiler
CN201180981Y (en) * 2008-03-07 2009-01-14 常汝光 Bidirectional combustion environment friendly energy-saving horizontal steam/water boiler
CN101881433A (en) * 2009-05-05 2010-11-10 广州迪森热能技术股份有限公司 Steam boiler capable of burning biomass
CN101963345A (en) * 2010-09-30 2011-02-02 浙江圣普新能源科技有限公司 Chain mobile grate boiler for combustible biomass formed fuel
CN202204144U (en) * 2011-07-28 2012-04-25 山西奥通环保自动锅炉有限公司 Grate boiler burning coal and biomass fuels
CN202484960U (en) * 2012-01-18 2012-10-10 湖北孝锅节能设备有限责任公司 Boiler-shell-type water-fire tube boiler

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB175737A (en) * 1920-11-18 1922-02-20 William Thomas Bell Improved construction of gas fired multitubular boiler
CN2033481U (en) * 1988-06-08 1989-03-01 大连轻工机械总厂 Water and smoke-tube boiler
CN2104409U (en) * 1991-06-10 1992-05-13 沈阳前进锅炉厂 Single-tube longitudinal shell type water-heating boiler
CN2385270Y (en) * 1998-03-14 2000-06-28 郭保林 Four or five return non-pressure boiler
CN201180981Y (en) * 2008-03-07 2009-01-14 常汝光 Bidirectional combustion environment friendly energy-saving horizontal steam/water boiler
CN101881433A (en) * 2009-05-05 2010-11-10 广州迪森热能技术股份有限公司 Steam boiler capable of burning biomass
CN101963345A (en) * 2010-09-30 2011-02-02 浙江圣普新能源科技有限公司 Chain mobile grate boiler for combustible biomass formed fuel
CN202204144U (en) * 2011-07-28 2012-04-25 山西奥通环保自动锅炉有限公司 Grate boiler burning coal and biomass fuels
CN202484960U (en) * 2012-01-18 2012-10-10 湖北孝锅节能设备有限责任公司 Boiler-shell-type water-fire tube boiler

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104848191A (en) * 2015-06-03 2015-08-19 陈小喜 Improved single-drum horizontal type coal-fired steam boiler

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