阅读说明：本技术 一种热量梯级回收废气全循环的烧结矿竖式冷却装置 (Vertical sinter ore cooling device with heat gradient recovery and waste gas full circulation ) 是由 许相波 张文成 孙俊杰 于 2019-09-30 设计创作，主要内容包括：一种热量梯级回收废气全循环的烧结矿竖式冷却装置。本发明涉及一种所述装置包括烧结机、下料管、料车、竖冷炉、料仓、布料管、排料管、皮带、重力除尘器、余热锅炉、多管除尘器、热水发生器、循环风机、布风器、汽轮发电机组、冷凝器、水泵、蓄热站以及热水车,所述料仓设置在竖炉的顶部,布料管设置在料仓的下方,所述排料管设置在竖炉的底部,所述竖炉通过重力除尘器、余热锅炉连接多管除尘器、热水发生器、循环风机,所述蓄热站连接热水发生器,所述汽轮发电机组通过冷凝器、水泵连接余热锅炉。该竖炉采用优化的结构形式,实现高效换热,保证烧结矿冷却需求。(A sintering ore vertical cooling device with heat gradient recovery and full circulation of waste gas. The invention relates to a device which comprises a sintering machine, a blanking pipe, a skip car, a vertical cooling furnace, a storage bin, a distributing pipe, a discharging pipe, a belt, a gravity dust collector, a waste heat boiler, a multi-pipe dust collector, a hot water generator, a circulating fan, an air distributor, a turbo generator set, a condenser, a water pump, a heat storage station and a hot water car. The shaft furnace adopts an optimized structural form, realizes high-efficiency heat exchange, and ensures the cooling requirement of sinter.)

1. The utility model provides a vertical cooling device of sintering deposit of heat step recovery waste gas complete cycle, a serial communication port, the device includes unloading pipe, skip, vertical cooling furnace, feed bin, distributing pipe, row's material pipe, belt, gravity dust remover, exhaust-heat boiler, multitube dust remover, hot water generator, circulating fan, air distributor, turbo generator set, condenser, water pump, heat accumulation station and hot-water vehicle, the feed bin sets up at the top of shaft furnace, and the distributing pipe sets up the below at the feed bin, arrange the material pipe setting in the bottom of shaft furnace, the shaft furnace passes through gravity dust remover, exhaust-heat boiler and connects multitube dust remover, hot water generator, circulating fan, the hot water generator is connected to the heat accumulation station, turbo generator set passes through condenser, water pump and connects exhaust-heat boiler.

2. The vertical sinter cooler with the heat gradient recovery and the full circulation of the waste gas as recited in claim 1, wherein a wear-resistant lining plate is arranged on the lower half part of the cross-section circle in the blanking pipe, so that the wear resistance of the pipe is improved; and a discharging gate is arranged at the bottom of the discharging pipe to control the charging of the trolley.

3. The vertical sinter cooler with stepped heat recovery and full exhaust gas circulation as claimed in claim 2, wherein the cross section of the shaft furnace is rectangular or square, and the cross section of the shaft furnace is preferably square to ensure that the materials in the furnace are uniformly distributed on the sections with different heights; the cross section of a top stock bin of the shaft furnace is rectangular/square or circular, and the cross section of the top stock bin is preferably circular in order to inhibit the particle size segregation of the top stock bin when a skip car dumps materials; the material center falling point of the material dumping of the skip coincides with the center of the storage bin so as to inhibit the granularity segregation in the storage bin caused by the material dumping of the skip.

4. The vertical sinter cooler with stepped heat recovery and full exhaust gas circulation as claimed in claim 3, wherein a plurality of distributing pipes are arranged to distribute the material into the furnace simultaneously, and the distributing pipes are matched with the discharging pipes with the same number, so that the material uniformity on the horizontal sections at different heights in the furnace is realized.

5. The vertical sinter cooler with stepped heat recovery and full exhaust gas circulation as claimed in claim 4, wherein the number of the distributing pipes is even and the distributing pipes are symmetrically distributed in the horizontal direction in the furnace; the number of the distributing pipes is preferably 4 corresponding to the square shaft furnace, the cross section of the hearth is divided into 4 squares in average, and the centers of the distributing pipes are superposed with the center of each square; the material discharging pipes are the same in number and correspond to the material distributing pipes up and down in position, so that the material in the furnace falls integrally, and a flowing dead zone is avoided.

6. The apparatus as claimed in claim 5, wherein the shaft furnace is arranged in a bottom center manner, the number of the air distributors and the number of the discharge pipes are the same, the air distributors are arranged at the center of the discharge pipes, four corners of the rectangular/square shaft furnace are chamfered at 45 degrees, and the chamfer distance is 0.4-0.6m, so as to reduce the air flow concentration at the corners.

7. The vertical sinter cooler with the heat gradient recovery waste gas complete cycle as claimed in claim 5 or 6, wherein the cross section of the central channel of the air distributor is square, the top of the air distributor is provided with an air cap, the side of the air distributor is provided with an air outlet, and the area of the side air outlet is equivalent to that of the central channel so as to reduce the airflow resistance of the air distributor.

8. The vertical sinter cooler with full heat step recovery exhaust gas circulation according to claim 7,

the waste heat boiler is provided with two steam drums, a medium-pressure superheater, a medium-pressure evaporator, a low-pressure superheater, a medium-pressure economizer, a low-pressure evaporator and a low-pressure economizer are sequentially arranged from the high-temperature side of flue gas, the inlet waste gas temperature of the waste heat boiler is 380 ℃, and the outlet waste gas temperature is 120 ℃; the parameters of the generated steam are 1.3MPa 380 ℃ and 0.3MPa 220 ℃, the steam is completely sent into a steam-supplementing and condensing type steam turbine generator unit to generate electricity, and the condensed water is sent into a waste heat boiler again to be recycled.

9. The vertical sinter cooler with full heat gradient recovery and waste gas circulation of claim 8, wherein the particle size of the mineral aggregate loaded into the skip car is kept stable, and the maximum particle size is controlled not to exceed 150 mm; the average temperature of the mineral aggregate should be kept stable and not lower than 400 ℃; the pressure at the top of the shaft furnace is controlled to be in a micro negative pressure state of-0.2 kPa-0kPa, so that the waste gas and dust are prevented from overflowing; the temperature of the waste gas at the outlet of the waste heat boiler is controlled to be not higher than 130 ℃, the temperature of the waste gas at the outlet of the hot water generator is controlled to be not higher than 90 ℃, and the cooled waste gas meets the requirement of mineral aggregate cooling; the medium pressure steam temperature parameter is 360-380 ℃, and the low pressure steam temperature parameter range is 200-220 ℃; the temperature of hot water at the outlet of the hot water generator is controlled within 90-95 ℃.

Technical Field

The invention relates to a cooling device, in particular to a sintering ore vertical cooling device with heat step recovery and full circulation of waste gas, and belongs to the technical field of sintering ore waste heat recovery.

Background

In the whole-flow steel production process, the energy consumption of the sintering process is high, the emission of waste gas and dust is large, and the traditional ring-type cooling process for sintered ores brings huge challenges to the development and upgrading of green manufacturing of the current steel industry. The vertical cooling of the sintering ore can obviously reduce the exhaust emission and the dust raising in the sintering production process, improve the energy recycling effect, solve the technology of the sintering development bottleneck, and is the future technology development direction.

In the related documents at present, the existing vertical cooling technology for sintered ores has a phenomenon of discharging cooling exhaust gas to different degrees, such as documents CN105627755A and CN106482530A, etc., and the exhaust gas after heat exchange has a high temperature (up to 120 ℃), and direct discharge causes a large amount of heat loss. However, if the coal is sent to the sintering shaft furnace for recycling, the high temperature of the inlet air cannot meet the requirement of mineral aggregate cooling, so that the ore discharge temperature is high, and normal production is difficult to continue. For the existing vertical cooling technology, the sufficient recovery of waste gas waste heat and the suitable vertical cooling ore discharging temperature have outstanding contradictions, the waste gas discharge cannot realize the full utilization of heat energy resources and the effective solution of waste gas dust discharge, and the long-term continuous and safe operation of the shaft furnace equipment is influenced if the waste gas is not discharged. Therefore, a new solution to solve the above technical problems is urgently needed.

Disclosure of Invention

The invention provides a sintering ore vertical cooling device with heat gradient recovery waste gas complete circulation, aiming at the problems in the prior art, the technical scheme is that the hot waste gas at the outlet of a shaft furnace is subjected to multi-section gradient recovery and utilization, various coupled waste heat products are produced by utilizing waste gas waste heat to meet the requirements of production and life, and simultaneously, the temperature of the waste gas is reduced to a reasonable level meeting the cooling requirement of sintering ore and then the waste gas is completely sent into the shaft furnace for cyclic utilization; the shaft furnace adopts an optimized structural form, realizes high-efficiency heat exchange, and ensures the cooling requirement of the sinter.

In order to achieve the purpose, the technical scheme of the invention is that the vertical sinter cooling device with the heat gradient recovery waste gas complete circulation comprises a blanking pipe, a skip car, a vertical cooling furnace, a storage bin, a distributing pipe, a discharging pipe, a belt, a gravity dust collector, a waste heat boiler, a multi-pipe dust collector, a hot water generator, a circulating fan, an air distributor, a turbo generator set, a condenser, a water pump, a heat storage station and a hot water car, wherein the storage bin is arranged at the top of the vertical furnace, the distributing pipe is arranged below the storage bin, the discharging pipe is arranged at the bottom of the vertical furnace, the vertical furnace is connected with the multi-pipe dust collector, the hot water generator and the circulating fan through the gravity dust collector and the waste heat boiler, the heat storage station is connected with the hot water generator, and the turbo generator set is connected with the waste heat boiler through the condenser and. The shaft furnace structure and the material distribution structure are optimally designed by the scheme, so that the heat exchange and cooling requirements of the mineral aggregate at the circulating air temperature are met; the air distribution structure matched with the furnace body structure realizes that air flow uniformly passes through the material layer and fully exchanges heat with the material; and a plurality of heat exchange surfaces coupled with the temperature level are arranged in the waste gas heat recovery link, so that the gradient reduction of the waste gas temperature is realized, waste heat products with poor temperature gradient are generated, and the waste gas temperature is reduced to a temperature range required by the shaft furnace process. The produced multi-stage waste heat products can be completely consumed by external users, and the continuous and stable operation of the process of the shaft furnace under the condition of no influence on the working condition change can be realized.

As an improvement of the invention, a wear-resistant lining plate is arranged in the lower half part of the cross section circle in the blanking pipe, so that the wear resistance of the pipeline is improved; and a discharging gate is arranged at an outlet at the bottom of the discharging pipe to control the charging of the trolley.

As an improvement of the invention, the cross section of the shaft furnace adopts a rectangle or a square, and the cross section of the shaft furnace is preferably square in order to ensure that materials in the furnace are uniformly distributed on the cross sections with different heights; the cross section of a bin at the top of the shaft furnace is rectangular/square or circular, and the cross section of the bin at the top is preferably circular in order to inhibit the particle size segregation of the bin at the top when a skip car dumps materials; the material center falling point of the material dumping of the skip coincides with the center of the storage bin so as to inhibit the granularity segregation in the storage bin caused by the material dumping of the skip.

As an improvement of the invention, a plurality of distributing pipes are arranged to distribute materials into the furnace simultaneously, and the distributing pipes are matched with the discharging pipes with the same number, so that the materials on the horizontal sections with different heights in the furnace are uniform. The number of the distributing pipes is even and the distributing pipes are symmetrically distributed in the horizontal direction in the furnace; the number of the distributing pipes is preferably 4 corresponding to the square shaft furnace, the cross section of the hearth is divided into 4 squares in average, and the centers of the distributing pipes are superposed with the center of each square; the material discharging pipes are the same in number and correspond to the material distributing pipes up and down in position, so that the material in the furnace falls integrally, and a flowing dead zone is avoided.

As an improvement of the invention, the shaft furnace adopts a bottom center air distribution mode, and the air distributors and the discharge pipes are the same in number and are positioned in the center of the discharge pipes. Four corners of the rectangular/square shaft furnace are chamfered at 45 degrees, and the chamfer angle distance is 0.4-0.6m, so that the air flow concentration at the corners is reduced.

As an improvement of the invention, the section of the central channel of the air distributor is square, the top of the air distributor is provided with an air cap, the side of the air distributor is provided with an air outlet, and the area of the side air outlet is equivalent to that of the central channel, so that the air flow resistance of the air distributor is reduced. The air distributor extends a certain distance into the furnace chamber, namely the air distributor is buried in the furnace burden to a certain depth, so as to shorten the distance difference from the top point of the blast cap to the side wall of the furnace and from the top point of the blast cap to the normal direction of the inclined plane of the material pile, and ensure that the air flow uniformly penetrates through the material. The air cavity at the bottom of the shaft furnace adopts bilateral symmetry air inlet to ensure that the air quantity of each air distributor is as uniform as possible. The gravity dust collector is adopted for primary dust removal of the waste gas, and the multi-tube dust collector is adopted for secondary dust removal, so that the stable operation requirements of the high-temperature section boiler, the low-temperature section heat exchanger and the circulating fan are met.

As an improvement of the invention, the waste heat boiler is provided with two steam drums, a medium-pressure superheater, a medium-pressure evaporator, a low-pressure superheater, a medium-pressure economizer, a low-pressure evaporator and a low-pressure economizer are sequentially arranged from the high-temperature side of flue gas, the inlet waste gas temperature of the waste heat boiler is 380 ℃, and the outlet waste gas temperature is 120 ℃; the parameters of the generated steam are 1.3MPa 380 ℃ and 0.3MPa 220 ℃, the steam is completely sent into a steam-supplementing and condensing type steam turbine generator unit to generate electricity, and the condensed water is sent into a waste heat boiler again to be recycled.

As an improvement of the invention, the grain diameter of the mineral aggregate loaded into the skip car is kept stable, and the maximum grain diameter is controlled not to exceed 150 mm; the average temperature of the mineral aggregate should be kept stable and not lower than 400 ℃; the pressure at the top of the shaft furnace is controlled to be in a micro negative pressure state of-0.2 kPa-0kPa, so that the waste gas and dust are prevented from overflowing; the temperature of the waste gas at the outlet of the waste heat boiler is controlled to be not higher than 130 ℃, the temperature of the waste gas at the outlet of the hot water generator is controlled to be not higher than 90 ℃, and the cooled waste gas meets the requirement of mineral aggregate cooling; the medium pressure steam temperature parameter is 360-380 ℃, and the low pressure steam temperature parameter range is 200-220 ℃; the temperature of hot water at the outlet of the hot water generator is controlled within 90-95 ℃. Under the working condition, the average discharging temperature of the outlet of the shaft furnace is 150 ℃, the short-time discharging temperature is not higher than 180 ℃, and the safe operation of the conveying belt is met.

Compared with the prior art, the invention has the advantages that 1) the waste heat boiler and the hot water generator are arranged to carry out two-stage heat exchange to recycle the heat of the waste gas, the temperature of the waste gas after the two-stage heat exchange is reduced to be below 90 ℃, and the waste gas is completely sent into the shaft furnace for cyclic utilization through the blower; 2) the waste heat boiler is provided with two steam drums, the superheaters, the evaporators and the coal economizers of two paths of steam are arranged in a matching and staggered mode according to the temperature of waste gas to generate superheated steam with two parameters, and a steam supplementing and condensing type steam turbine is adopted to realize all power generation; 3) the hot water generator further cools the waste gas by cold water through the heat exchanger to generate hot water with the temperature of 90-95 ℃. The cold water is municipal domestic water, and the generated hot water enters the heat storage station and is delivered to a hot water user by using a hot water vehicle; 4) the method effectively improves the uniformity of material distribution in the furnace and the gas-solid heat transfer effect by adopting an optimized shaft furnace structure and a cooling process of temperature coupling matching, improves the temperature of waste gas at the outlet of the shaft furnace, reduces the ore discharge temperature, simultaneously realizes the complete recycling of waste gas and waste heat resources of the vertical cooling furnace, eliminates the discharge of waste gas and dust in the cooling process of the sintered ore, greatly improves the waste heat recycling efficiency of sensible heat of the sintered ore, and improves the heat efficiency of the vertical cooling furnace of the sintered ore by more than 70 percent compared with the traditional annular cooling mode.

Drawings

FIG. 1 is a schematic view of a sinter vertical cooling energy cascade recycling system;

in the figure: 1-sintering machine, 2-blanking pipe, 3-skip, 4-vertical cooling furnace, 5-stock bin, 6-distributing pipe, 7-discharging pipe, 8-belt, 9-gravity dust remover, 10-waste heat boiler, 11-multi-pipe dust remover, 12-hot water generator, 13-circulating fan, 14-air distributor, 15-turbo generator set, 16-condenser, 17-water pump, 18-heat storage station, and 19-hot water truck.

The specific implementation mode is as follows:

for the purpose of enhancing an understanding of the present invention, the present embodiment will be described in detail below with reference to the accompanying drawings.

Example 1: referring to fig. 1, a sintering ore vertical cooling device with heat gradient recovery and full circulation of waste gas, the device comprises a sintering machine 1, a blanking pipe 2, a skip 3, a vertical cooling furnace 4, a bin 5, a distributing pipe 6, a discharging pipe 7, a belt 8, a gravity dust collector 9, a waste heat boiler 10, a multi-pipe dust collector 11, a hot water generator 12, a circulating fan 13, an air distributor 14, a turbo generator set 15, a condenser 16, a water pump 17, a heat storage station 18 and a hot water truck 19, wherein the bin 5 is arranged at the top of the vertical furnace 4, the distributing pipe 6 is arranged below the bin 5, the discharging pipe 7 is arranged at the bottom of the vertical furnace, the vertical furnace 4 is connected with the dust collector 11, the hot water generator 12 and the circulating fan 13 through the gravity dust collector 9 and the waste heat boiler 10, the heat storage station 18 is connected with the hot water generator 12, the turbo generator set 15 is connected with the condenser 16, The water pump 17 is connected with the waste heat boiler 10, and a wear-resistant lining plate is arranged in the lower half part of the cross section circle in the blanking pipe, so that the wear resistance of the pipeline is improved; and a discharging gate is arranged at an outlet at the bottom of the discharging pipe to control the charging of the trolley. The cross section of the shaft furnace is rectangular or square, and the cross section of the shaft furnace is preferably square in order to ensure that materials in the furnace are uniformly distributed on the cross sections with different heights; the cross section of a bin at the top of the shaft furnace is rectangular/square or circular, and the cross section of the bin is preferably circular in order to inhibit the particle size segregation of the bin at the top when a skip car dumps materials; the material center falling point of the material dumping of the skip coincides with the center of the storage bin so as to inhibit the granularity segregation in the storage bin caused by the material dumping of the skip. The shaft furnace is provided with a plurality of distributing pipes for distributing materials into the furnace simultaneously, and the distributing pipes are matched with the discharging pipes with the same number, so that the materials on the horizontal cross sections with different heights in the furnace are uniform. The number of the distributing pipes is even and the distributing pipes are symmetrically distributed in the horizontal direction in the furnace; the number of the distributing pipes is preferably 4 corresponding to the square shaft furnace, the cross section of the hearth is divided into 4 squares in average, and the centers of the distributing pipes are superposed with the center of each square; the material discharging pipes are the same in number and correspond to the material distributing pipes up and down in position, so that the material in the furnace falls integrally, and a flowing dead zone is avoided. The number of the discharge ports is the same as that of the distributing pipes, and the positions of the discharge ports correspond to those of the distributing pipes up and down. The shaft furnace adopts a bottom center air distribution mode, and the number of the air distributors is the same as that of the discharge pipes and is positioned in the center of the discharge pipes. Four corners of the rectangular/square shaft furnace are chamfered at 45 degrees, and the chamfer angle distance is 0.4-0.6m, so that the air flow concentration at the corners is reduced. The cross section of the channel of the air distributor is square, the top of the air distributor is provided with an air cap, the side of the air distributor is provided with an air outlet, and the area of the air outlet is equivalent to the cross section of the corresponding channel so as to reduce the airflow resistance. The air distributor extends a certain distance into the furnace chamber, namely the air distributor is buried in the furnace burden to a certain depth, so as to shorten the distance difference from the top point of the blast cap to the side wall of the furnace and from the top point of the blast cap to the normal direction of the inclined plane of the material pile, and ensure that the air flow uniformly penetrates through the material. The air cavity at the bottom of the shaft furnace adopts bilateral symmetry air inlet to ensure that the air quantity of each air distributor is as uniform as possible. The gravity dust collector is adopted for primary dust removal of the waste gas, and the multi-tube dust collector is adopted for secondary dust removal, so that the stable operation requirements of the high-temperature section boiler, the low-temperature section heat exchanger and the circulating fan are met.

The waste heat boiler is provided with two steam drums, a medium-pressure superheater, a medium-pressure evaporator, a low-pressure superheater, a medium-pressure economizer, a low-pressure evaporator and a low-pressure economizer are sequentially arranged from the high-temperature side of flue gas, the inlet waste gas temperature of the waste heat boiler is 380 ℃, and the outlet waste gas temperature is 120 ℃; the parameters of the generated steam are 1.3MPa 380 ℃ and 0.3MPa 220 ℃, the steam is completely sent into a steam-supplementing and condensing type steam turbine generator unit to generate electricity, and the condensed water is sent into a waste heat boiler again to be recycled. The particle size of the mineral aggregate loaded into the skip car is kept stable, and the maximum particle size is controlled to be not more than 150 mm; the average temperature of the mineral aggregate should be kept stable and not lower than 400 ℃; the pressure at the top of the shaft furnace is controlled to be in a micro negative pressure state of-0.2 kPa-0kPa, so that the waste gas and dust are prevented from overflowing; the temperature of the waste gas at the outlet of the waste heat boiler is controlled to be not higher than 130 ℃, the temperature of the waste gas at the outlet of the hot water generator is controlled to be not higher than 90 ℃, and the cooled waste gas meets the requirement of mineral aggregate cooling; the medium pressure steam temperature parameter is 360-380 ℃, and the low pressure steam temperature parameter range is 200-220 ℃; the temperature of hot water at the outlet of the hot water generator is controlled within 90-95 ℃. Under the working condition, the average discharging temperature of the outlet of the shaft furnace is 150 ℃, the short-time discharging temperature is not higher than 180 ℃, and the safe operation of the conveying belt is met.

The application example is as follows: referring to fig. 1, a vertical cooling device for sintering ore with heat gradient recovery and full circulation of waste gas, the vertical furnace adopts a rectangular cross section structure, the size of the vertical furnace is 10 m 15m, a top stock bin is provided with 6 distributing pipes, the bottom of the vertical furnace is provided with 6 discharging pipes, the distributing pipes are aligned with the centers of the discharging pipes, and an inner cavity of the vertical furnace is divided into 6 uniform squares. The shaft furnace adopts a bottom center air distribution mode, and 6 air distributors are respectively arranged at the center of the discharge pipe. The top of the air distributor is provided with an air cap which adopts a side air outlet mode. The waste heat boiler is provided with two steam drums, a medium-pressure superheater, a medium-pressure evaporator, a low-pressure superheater, a medium-pressure economizer, a low-pressure evaporator and a low-pressure economizer are sequentially arranged from the high-temperature side of flue gas, the inlet waste gas temperature of the waste heat boiler is 380 ℃, and the outlet waste gas temperature is 120 ℃; the parameters of the generated steam are 1.3MPa 370 ℃ and 0.3MPa 200 ℃, the steam is completely sent into a steam-supplementing and condensing type steam turbine generator unit to generate electricity, and the condensed water is sent into a waste heat boiler again to be recycled. The waste gas at the outlet of the waste heat boiler is further subjected to secondary dust removal by a multi-tube dust remover so as to meet the stable operation requirements of the low-temperature section heat exchanger and the circulating fan; the hot water generator further performs counter-current heat exchange between the live water and the waste gas, the generator adopts a finned tube heat exchanger to reduce the temperature of the waste gas to 80 ℃, and the waste gas enters the shaft furnace again through an air blower; hot water with the temperature of 95 ℃ generated by the hot water generator enters the heat storage station and is transported to a user by a hot water vehicle.

The ore discharging temperature of a plurality of discharging openings is maintained between 120 ℃ and 170 ℃ during production in the embodiment, so that the requirement of continuous and safe production is met; the waste gas and dust emission in the sinter cooling process is eliminated, and the environment is obviously improved; the steam quantity of the waste heat boiler reaches 29-30t/h, the generated energy reaches 5000kW, the steam recovery quantity is improved by over 100 percent compared with the annular cooling steam yield before modification, and the energy-saving effect is obvious.

The working process is as follows: referring to fig. 1, after the hot ore turned down by the sintering trolley 1 is roughly crushed, the granularity is less than 150mm, and the temperature is about 400-450 ℃; a skip car 3 at the bottom of the charging pipe is loaded through a discharging pipe 2, the skip car 3 lifts hot ore to the top of a shaft furnace 4, and the ore is poured into a storage bin 5. Mineral aggregate enters the inner cavity of the shaft furnace 4 along the distributing pipe 6 under the action of self gravity, moves downwards and carries out reverse heat exchange with internal airflow, and the mineral aggregate with the temperature of 120 plus 150 ℃ after being cooled is discharged to the conveying belt 8 from the discharge pipe 7 at the bottom of the shaft furnace.

The 80-90 ℃ cold air blown out by the circulating fan 13 enters the interior of the shaft furnace 4 from the air distributor 14 positioned at the bottom of the shaft furnace 4, exchanges heat with mineral aggregate from bottom to top, generates 380 ℃ hot air, flows out of the shaft furnace 4 from an outlet positioned at the top of the side wall, enters the waste heat boiler 10 after passing through the gravity dust collector 9, generates 1.3MPa 370 ℃ and 0.3MPa 200 ℃ superheated steam respectively, and the steam enters the condensing steam-supplementing type turbo generator unit 15 for power generation and then enters the boiler again for circulation after passing through the condenser 16.

The waste gas with the temperature of less than 120 ℃ at the outlet of the waste heat boiler 10 enters a hot water generator 12 after being dedusted by a multi-tube deduster 11, is subjected to heat exchange with internal cold water to be cooled to 80 ℃, and is sent into the shaft furnace 4 by an air blower 13 for cyclic utilization; the water heater 12 uses municipal domestic water as a cooling medium, generates hot water at 90-95 ℃ and stores the hot water in the heat storage station 16, and the generated hot water is sent to users by using a hot water truck.

It should be noted that the above-mentioned embodiments are not intended to limit the scope of the present invention, and all equivalent modifications and substitutions based on the above-mentioned technical solutions are within the scope of the present invention as defined in the claims.