Annular cooling medium and low temperature waste gas upgrading utilization system

Abstract

The utility model discloses a system for upgrading and utilizing medium-temperature and low-temperature waste gas in ring cooling. The method comprises the following steps: sequentially carrying out heat and oxygen supplementation treatment, stepped heat exchange and selective split-flow steam supplementation treatment on sintering ring cold medium and low temperature waste gas to obtain oxygen-enriched hot waste gas and oxygen-enriched steam-enriched hot waste gas which can be directly used for sintering, and intermediate products such as high-parameter steam and industrial hot water; therefore, the waste heat of the sintering ring cooling medium-temperature and low-temperature waste gas is recovered at low cost and high efficiency, and meanwhile, the discharge amount of the waste gas is also remarkably reduced; and further, the oxygen-enriched hot waste gas and the oxygen-enriched steam-enriched hot waste gas are respectively returned to the sintering front-end material surface and the sintering rear-end material surface for oxygen-enriched hot air sintering and oxygen-enriched steam injection sintering, and the quality index of a sintered ore product is further improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the treatment of sintering ring cold waste gas, specifically relates to a system of middle and low temperature waste gas upgrading utilization in ring cooling belongs to sintering ring cold waste gas treatment technical field. BACKGROUND

[0002] In the sinter production process, the sinter cake is unloaded from the sintering machine, and the temperature can reach 700~800 DEG C, and the physical sensible heat resource carried is the most important part of the sintering waste heat resource. In the process of using air to cool the sinter, the sinter temperature drops to below 150 DEG C, and a large amount of hot air is generated. Generally, the cooling waste gas temperature of different parts of the sintering ring cooling machine is different, and the temperature gradually decreases from the material receiving end to the discharge end, which is generally divided into three sections: high temperature zone with temperature higher than 250 DEG C, medium temperature zone with temperature of 150 DEG C~250 DEG C and low temperature zone with temperature lower than 150 DEG C.

[0003] In actual production, many enterprises have built sintering waste heat recovery systems to utilize the high-temperature cooling waste gas of the ring cooling machine in the form of waste heat power generation. The middle and low temperature section cooling waste gas has low temperature, and the boiler heat exchange can only produce low parameter steam, so the waste heat utilization efficiency is low, the utilization cost is high, and some enterprises even directly discharge, which not only wastes resources but also pollutes the environment. In addition, some enterprises use part of the flue gas in the ring cooling machine to return to the upper sealing cover of the sintering machine in the form of hot air sintering to improve the heat utilization rate of the ring cooling waste gas, hoping to reduce the sintering fuel consumption and improve the sinter quality while reducing the ring cooling flue gas emission. For example, patent CN108731486A proposes a middle and low temperature waste gas recycling system and recycling method in the ring cooling machine, which sets a smoke hood above the sintering machine and connects it with the ring cooling machine, and the middle and low temperature waste gas of 80 DEG C~250 DEG C in the ring cooling machine is converted from direct discharge into the atmosphere to direct reuse in the bed layer of the sintering machine, so as to replace the air sucked from the surrounding atmosphere for the sintering of raw and auxiliary fuels, so as to fully utilize the sensible heat in the middle and low temperature waste gas and eliminate the pollution of direct discharge of dust-containing waste gas to the atmosphere. Patent CN106931792B proposes a method and device for comprehensive utilization of ring cooling machine waste gas, which uses the middle temperature waste gas of 150-220 DEG C for ORC low temperature power generation through heat exchange, and the used waste gas is used for hot air sintering in the sintering process, or it is mixed with the ring cooling low temperature cooling waste gas below 150 DEG C to form waste gas of about 100 DEG C, and returned to the sintering machine trolley for hot air sintering.

[0004] In summary, in the prior art, directly using the medium and low temperature section cooling waste gas for boiler heat exchange can only produce low parameter steam, the waste heat preheating utilization efficiency is low, the utilization cost is high, and returning the medium and low temperature waste gas to the sintering instead of air can utilize the waste heat to some extent from the energy angle, but since the cooling waste gas temperature is much higher than air, the gas volume expansion leads to the oxygen concentration being much lower than air (about 310 mg / L), the oxygen amount drawn into the sintering material layer is reduced, which is not conducive to fuel combustion and affects the sinter production quality, and the waste gas must be cooled to about 100℃ before being returned to the sintering, so the waste heat utilization efficiency in the sintering process is low. Practical new type content

[0005] In view of the problems in the prior art that the sintering ring cooling medium and low temperature waste gas direct waste heat recovery utilization efficiency is low, the cost is high, the temperature must be reduced before being returned to the sintering, and the waste heat utilization efficiency is low, the utility model provides a system for upgrading and utilizing ring cooling medium and low temperature waste gas, which obtains oxygen-rich hot waste gas and oxygen-rich and steam-rich hot waste gas which can be directly used for sintering, and intermediate products such as high parameter steam and industrial hot water by sequentially treating the sintering ring cooling medium and low temperature waste gas through heat and oxygen supplementing, step-by-step heat exchange and selective shunt steam supplementing, thereby realizing the recovery of the sintering ring cooling medium and low temperature waste heat at low cost and high efficiency, significantly reducing the waste gas emission, and further improving the sinter production quantity and quality index.

[0006] To achieve the above technical purpose, the technical scheme adopted by the utility model is specifically as follows:

[0007] A system for upgrading and utilizing ring cooling medium and low temperature waste gas, which comprises a shell and an inner cavity. The shell bottom is provided with a waste gas inlet connected with the inner cavity. The inner cavity is divided into a heat and oxygen supplementing area, a first heat exchange area, a second heat exchange area and a shunt steam supplementing area in sequence from bottom to top. The ring cooling medium and low temperature waste gas is converted into oxygen-rich hot waste gas and oxygen-rich and steam-rich hot waste gas which can be directly used for sintering process after sequentially passing through the heat and oxygen supplementing area, the first heat exchange area, the second heat exchange area and the shunt steam supplementing area.

[0008] As a preferred, the system further comprises a sintering machine and a ring cooling machine. According to the sintering material direction: a front section smoke hood and a rear section smoke hood are sequentially arranged on the sintering machine, and a one section air hood, a two section air hood and a three section air hood are sequentially arranged on the ring cooling machine. The air outlets of the two section air hood and the three section air hood are connected with the waste gas inlet through air inlet pipes. The oxygen-rich hot waste gas outlet of the shunt steam supplementing area is connected with the air inlet of the front section smoke hood through a first circulating gas conveying pipe, and the oxygen-rich and steam-rich hot waste gas outlet of the shunt steam supplementing area is connected with the air inlet of the rear section smoke hood through a second circulating gas conveying pipe. Preferably, an electric plug-in valve is arranged in the waste gas inlet.

[0009] As preferred, on the sintering machine: the front section hood covers the 1 / 10 to 4 / 10 section of the material surface between the sintering ignition point and the sintering end point; the rear section hood covers the 5 / 10 to 8 / 10 section of the material surface between the sintering ignition point and the sintering end point.

[0010] As preferred, on the circular cooler: the air outlet of the third section hood is connected to the bottom air inlet of the second section of the circular cooler through an air supply pipe, and the air outlet of the second section hood is connected to the exhaust gas inlet through an air inlet pipe.

[0011] As preferred, an oxygen-enriched burner is arranged in the heat and oxygen supplementing area, and a combustible gas pipeline and an oxygen-enriched gas pipeline are connected to the oxygen-enriched burner.

[0012] As preferred, a plurality of oxygen-enriched burners are arranged in the heat and oxygen supplementing area, and a combustible gas pipeline and an oxygen-enriched gas pipeline are independently connected to each oxygen-enriched burner.

[0013] As preferred, in the primary heat exchange area, from bottom to top, a high-parameter steam superheater, a high-parameter steam evaporator, a high-parameter economizer, a deoxygenated evaporator, and a low-parameter economizer are arranged in sequence. Outside the primary heat exchange area, a steam drum, a deoxygenator, a desalted water pipe network, and a steam power generation device are arranged. The front end of the high-parameter steam superheater is connected to the steam power generation device through a pipeline and a valve, and the rear end thereof is connected to the steam drum through a pipeline. The front end and the rear end of the high-parameter steam evaporator are both connected to the steam drum through a pipeline. The front end of the high-parameter economizer is connected to the deoxygenator through a pipeline, and the rear end thereof is connected to the steam drum through a pipeline. The front end and the rear end of the deoxygenated evaporator are both connected to the deoxygenator through a pipeline. The front end of the low-parameter economizer is connected to the desalted water pipe network through a pipeline and a valve, and the rear end thereof is connected to the deoxygenator through a pipeline.

[0014] As preferred, in the secondary heat exchange area, an industrial water heater is arranged, and outside the secondary heat exchange area, an industrial water pipe network and a hot water utilization pipeline are arranged. The front end of the industrial water heater is connected to the industrial water pipe network, and the rear end thereof is connected to the hot water utilization pipeline.

[0015] As preferred, in the shunt steam supplementing area, a water mist spray pipe and a shunt baffle are arranged. The top end of the shunt baffle is connected to the shell and separates the shunt steam supplementing area into two horizontally parallel shunt chambers. The water mist spray pipe is arranged in one of the shunt chambers and has an oxygen-enriched and steam-enriched hot exhaust gas outlet at the top of the shunt chamber, and an oxygen-enriched hot exhaust gas outlet at the top of the other shunt chamber. Preferably, the top end of the shunt baffle is hinged to the shell, so that the shunt baffle can swing in the horizontal direction to adjust the size of the two shunt chambers.

[0016] As preferred, according to the material flow direction, the ring cooler comprises a ring cooling front section, a ring cooling middle section and a ring cooling rear section, and the bottom air inlet of the ring cooling front section and the bottom air inlet of the ring cooling rear section are independently connected with cooling fans respectively.

[0017] In the utility model, the height of the shell is 1-300m, preferably 3-100m, more preferably 5-50m; the thickness of the shell is 1-100cm, preferably 1.5-60cm, more preferably 3-40cm. The height of the heat supplementing and oxygen supplementing area, the primary heat exchange area, the secondary heat exchange area and the shunt steam supplementing area in the vertical direction is same or different.

[0018] In the utility model, aiming at the problems that the sintering ring cooling middle and low temperature waste gas (the ring cooling middle temperature waste gas discharged by the ring cooling middle section and the ring cooling low temperature waste gas discharged by the ring cooling rear section) is difficult to utilize efficiently in the prior art, the utility model obtains oxygen-rich high temperature hot flue gas by setting the waste gas upgrading conversion mechanism with the heat supplementing and oxygen supplementing area, the primary heat exchange area, the secondary heat exchange area and the shunt steam supplementing area to supplement oxygen and heat for the ring cooling middle and low temperature waste gas, the oxygen-rich high temperature hot flue gas can directly carry out cascade heat exchange to obtain high parameter hot steam for power generation, then carries out shunt steam supplementing treatment, obtains oxygen-rich hot waste gas and oxygen-rich and steam-rich hot waste gas which can be directly used for sintering. That is to say, the utility model realizes efficient utilization of the sintering ring cooling middle and low temperature waste gas by the upgrading conversion mechanism, and also realizes full quality consumption of the waste gas, without redundant waste gas emission.

[0019] In the utility model, for the high temperature waste gas (the waste gas discharged by the ring cooling front section) of the sintering ring cooling, since the temperature of the part of high temperature waste gas is high (the air temperature is generally > 250 DEG C), the waste heat utilization can be directly carried out, for example, the high parameter steam is obtained by being transported to the preheating boiler to produce and is used for power generation or other metallurgical procedures.

[0020] In the utility model, the low-temperature waste gas discharged from the ring cooling machine ring cooling rear section is recycled to the ring cooling machine ring cooling middle section cooling air inlet to replace all or part of the cooling air as the cooling air of the ring cooling middle section to cool the sintered material, through the recycling of the low-temperature waste gas, on the one hand, the direct discharge of the low-temperature waste gas can be completely avoided, and the temperature of the medium-temperature waste gas discharged from the ring cooling middle section is increased to 200-300 DEG C from the original 150-250 DEG C, the sensible heat of the material is enriched, and the efficient recovery of the subsequent heat is beneficial; on the other hand, through the replacement of all or part of the cooling air entering the ring cooling middle section, the total amount of the cooling air of the ring cooling machine is significantly reduced, and then the production of the hot waste gas is significantly reduced, and finally the heat discharged with the waste gas is also significantly reduced.

[0021] In the utility model, although the temperature of the medium-temperature waste gas discharged from the ring cooling middle section is increased compared with the waste gas temperature of the traditional process, the direct utilization still has the disadvantage that the waste heat utilization efficiency is relatively low due to the relatively low air temperature (that is, it is difficult to obtain high-parameter steam through heat exchange with industrial hot water), therefore, the medium-temperature waste gas is transported into the heat-supplying and oxygen-supplying area to realize oxygen-supplying and heat-supplying through oxygen-enriched combustion, the heat-supplying and oxygen-supplying area generally uses low-value combustible gas (such as blast furnace gas, converter gas and other low-value combustible gas easily obtained in the steel plant area, which can realize self-sufficiency, and at the same time, the low-value combustible gas is also fully recycled; if necessary, high-value fuel or gas can also be used, but the relative cost will be higher) to combust with oxygen-enriched gas to supplement the oxygen-enriched gas (oxygen excess), which is beneficial to promoting the full combustion of the low-value combustible gas, and then improving the flue gas temperature, and on the other hand, the oxygen concentration in the flue gas can be improved, that is, the oxygen concentration is improved while the heat of the sintering ring cooling medium-temperature and low-temperature waste gas is supplemented, and after the oxygen-enriched combustion, the medium-temperature and low-temperature waste gas is changed into oxygen-enriched high-temperature hot flue gas with a temperature of 400 DEG C or more and an oxygen concentration of 140 mg / L or more. That is, through the oxygen-enriched reheating of the medium-temperature and low-temperature waste gas, the medium-temperature and low-temperature waste gas which is difficult to directly utilize is changed into oxygen-enriched high-temperature hot flue gas which is easy to directly utilize, and at the same time, the efficient recycling of the low-value combustible gas in the plant area is realized.

[0022] In the utility model, adopt the way of gradient heat exchange (high temperature heat exchange in primary heat exchange area, low temperature heat exchange in secondary heat exchange area) to realize the efficient recycling of oxygen-rich high temperature hot flue gas, that is, the oxygen-rich high temperature hot flue gas is sequentially subjected to high temperature indirect heat exchange in the primary heat exchange area, secondary low temperature indirect heat exchange in the secondary heat exchange area and shunt atomization temperature control cooling homogenization in the shunt steam supplement area, respectively producing high quality steam, industrial hot water and oxygen-rich hot waste gas and oxygen-rich steam-rich hot waste gas which can be directly reused for sintering. Specifically, first, the oxygen-rich high temperature hot flue gas is subjected to heat exchange with industrial hot water in the primary heat exchange area to produce high parameter steam with pressure >=1.5MPa and temperature >=350 DEG C which is used for power generation, and the outlet flue gas temperature of the primary heat exchange area is reduced to 160 DEG C-200 DEG C (oxygen-rich medium temperature hot flue gas); then, the oxygen-rich medium temperature hot flue gas is subjected to heat exchange with normal temperature water (industrial water) in the secondary heat exchange area to produce industrial hot water with temperature >=90 DEG C, which can be reused in the primary heat exchange area for heat exchange with the oxygen-rich high temperature hot flue gas to produce high quality steam or used in the sintering production process, and the outlet flue gas temperature of the secondary heat exchange area is reduced to 130-160 DEG C (oxygen-rich hot waste gas); finally, part (for example, 30%-55%) of the oxygen-rich hot waste gas is subjected to atomized water spray heat exchange cooling in the shunt steam supplement area, further reducing the flue gas temperature, while the atomized water absorbs heat and vaporizes into water vapor, finally producing oxygen-rich steam-rich hot waste gas with temperature of 120 DEG C-155 DEG C, oxygen concentration of 320mg / L-420mg / L and water vapor concentration of 3%-5% which can be directly reused for sintering. That is to say, the utility model realizes the step-by-step efficient use of oxygen-rich high temperature hot flue gas by the way of gradient heat exchange, and obtains multiple products which can be directly internally circulated, realizes the complete consumption and utilization of oxygen-rich high temperature hot flue gas without waste gas emission.

[0023] In the utility model, the oxygen-rich hot waste gas and the oxygen-rich steam-rich hot waste gas are respectively sent to the front and rear sintering sections of the sintering machine through the circulating gas pipes to replace normal temperature air to enter the sintering material layer to promote the sintering reaction. The front sintering section refers to the section where the first tenth to the fourth tenth of the material surface between the sintering ignition point and the sintering endpoint are located, and the rear sintering section refers to the section where the fifth tenth to the eighth tenth of the material surface between the sintering ignition point and the sintering endpoint are located. The oxygen-rich hot waste gas is directly returned to the front sintering section material surface for hot air sintering to improve the upper limit of the hot air allowable temperature and realize oxygen-rich sintering, optimize the sintering reaction process of the front and middle sintering sections and improve the sinter production quality index; and the oxygen-rich steam-rich hot waste gas is directly returned to the rear sintering section material surface for oxygen-rich steam injection sintering to optimize the sintering reaction process of the middle and rear sintering sections and improve the sinter production quality.

[0024] In this invention, an oxygen-enriched burner is provided in the supplementary heating and oxygenation zone to increase the temperature and oxygen concentration of the medium and low temperature exhaust gas in the annular cooling system. It can be an independent supplementary heating burner and oxygenation nozzle, or an oxygen-enriched combustion burner. The upper end of the supplementary heating and oxygenation zone is connected to the lower end of the primary heat exchange zone.

[0025] In this invention, a high-parameter steam superheater, a high-parameter steam evaporator, a high-parameter economizer, a deaerator evaporator, and a low-parameter economizer are arranged sequentially from bottom to top in the primary heat exchange zone. A steam drum, a deaerator, a demineralized water pipeline network, and a steam power generation device are arranged on the outside of the primary heat exchange zone. The oxygen-enriched high-temperature hot flue gas from the supplementary heat and oxygenation zone undergoes indirect heat exchange with the industrial hot water sent into the primary heat exchange zone. After absorbing the heat carried by the oxygen-enriched high-temperature hot flue gas, the industrial hot water is converted into high-parameter steam for power generation. The oxygen-enriched high-temperature hot flue gas is then transformed into oxygen-enriched medium-temperature hot flue gas and enters the secondary heat exchange zone.

[0026] In this invention, an industrial water heater is installed in the secondary heat exchange zone, and the industrial water heater is connected to an external industrial water pipeline network. The industrial water pipeline network sends industrial cold water (at ambient temperature) into the industrial water heater to indirectly exchange heat with the oxygen-enriched medium-temperature hot flue gas from the primary heat exchange zone. After absorbing heat, the industrial cold water produces industrial hot water, which is supplied to the primary heat exchange zone and the sintering production process. After heat exchange and cooling, the oxygen-enriched medium-temperature hot flue gas is transformed into oxygen-enriched hot waste gas and enters the diversion and steam replenishment zone.

[0027] In this invention, a water mist spray pipe and a diversion baffle are installed in the diversion steam replenishment zone. The top of the diversion baffle is connected to the shell and divides the diversion steam replenishment zone into two horizontally parallel diversion chambers. The diversion baffle can swing between the two diversion chambers, thereby adjusting the amount of oxygen-rich hot waste gas from the secondary heat exchange zone entering the two diversion chambers (for example, the ratio of the intake volume of the left diversion chamber to the right diversion chamber is 30-55%:45-70%). In one of the diversion chambers (e.g., Figure 1 The left-side diversion chamber is equipped with a water mist spray pipe, which is used to spray water mist onto the oxygen-rich hot waste gas entering the diversion chamber. This reduces the temperature of the waste gas while increasing the concentration of water vapor in the waste gas, thereby obtaining oxygen-rich and steam-rich hot waste gas that can be directly sintered and reused.

[0028] In this invention, the system and method employ a combination of technologies such as cascade utilization of low-temperature waste gas from sintering ring cooling, simultaneous heating and oxygenation of medium-temperature waste gas for quality improvement, and staged heat exchange for rich steam. This eliminates the direct emission of low-temperature waste gas. Then, low-value coal gas from the steel plant is used for combustion to supplement heating and oxygenation, or oxygen-enriched combustion. This raises the temperature of the medium and low-temperature waste gas to meet the requirements for producing high-parameter steam while significantly increasing the oxygen content in the waste gas. After heat exchange to produce high-quality steam and industrial hot water, selective diversion and water mist spraying are used to further control the flue gas temperature, while simultaneously achieving the goal of containing a certain amount of water vapor in the waste gas. By adopting the above technical measures, firstly, the recovery of waste heat from the intermediate and low-temperature exhaust gases in the sintering ring cooler has been transformed from direct emission or recovery of low-parameter steam to recovery of high-parameter steam, thus improving the quality and efficiency of waste heat recovery; secondly, while supplementing heat, oxygen and steam are added to the intermediate and low-temperature exhaust gases, increasing the oxygen concentration in the exhaust gas finally returned to sintering (≥ 310 mg / L of oxygen in ambient air), ensuring that the oxygen content of the exhaust gas entering sintering at temperatures > 120°C can still meet the needs of the sintering reaction, eliminating the adverse effects of oxygen scarcity on sintering at high temperatures. The negative impacts of the process are mitigated by improving the utilization rate of waste heat from the sintering process. Third, oxygen-enriched hot waste gas and oxygen-enriched steam-enriched hot waste gas are selectively returned to the waste gas at the front and rear material surfaces of the sintering process for oxygen-enriched hot air sintering and oxygen-enriched steam injection sintering. Compared with ordinary air, this waste gas contains both excess oxygen and some steam, thus combining the improvement effects of existing "oxygen-enriched sintering technology" and "material surface steam injection technology" on sintering. When this waste gas is used to replace air for sintering, the quality indicators of sintered minerals can be significantly improved and pollutant emissions can be reduced.

[0029] Compared with the prior art, the beneficial technical effects of this utility model are as follows:

[0030] 1. The system and method provided by this utility model realize the transformation of the recovery of waste heat from the medium and low temperature exhaust gas of sintering ring cooling from direct emission or recovery of low-parameter steam to recovery of high-parameter steam, achieving zero exhaust gas emission and significantly improving the quality and efficiency of waste heat recovery. At the same time, oxygen is added to the medium and low temperature exhaust gas during the heat replenishment, increasing the oxygen concentration in the exhaust gas finally returned to sintering. When the exhaust gas temperature is >120℃, the oxygen content of the exhaust gas entering the sintering material layer can still meet the reaction requirements, eliminating the negative impact of oxygen scarcity at high temperatures on the sintering process and improving the utilization rate of waste heat in the sintering process. In addition, oxygen-enriched hot exhaust gas and oxygen-enriched steam-enriched hot exhaust gas can be generated separately and returned to the front and rear material surfaces of the sintering for oxygen-enriched hot air sintering and oxygen-enriched steam injection sintering, respectively, improving the quality of sintered ore and reducing pollutant emissions.

[0031] 2: The system and method provided by this utility model integrates units such as heat replenishment, oxygen enrichment, temperature control, and steam injection. It combines the positive effects of technologies such as cascade utilization of low-temperature waste gas from sintering ring coolers, simultaneous heat and oxygen replenishment and quality improvement of medium-temperature waste gas, and staged heat exchange and steam enrichment, which greatly improves the waste heat utilization efficiency of low-temperature waste gas in the ring cooler and reduces waste gas emissions. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the system for upgrading and utilizing medium and low temperature waste gas in the ring cooling system of this utility model.

[0033] Figure 2 This is a schematic diagram of the structure of the system described in this utility model when it has a sintering machine and an annular cooler.

[0034] Attached reference numerals: 1: Exhaust gas inlet; 101: Electric gate valve; 2: Heat and oxygen supplementation zone; 201: Oxygen-enriched burner; 202: Combustible gas pipeline; 203: Oxygen-enriched gas pipeline; 3: Primary heat exchange zone; 301: High-parameter steam superheater; 302: High-parameter steam evaporator; 303: High-parameter economizer; 304: Deaerator evaporator; 305: Low-parameter economizer; 306: Steam drum; 307: Deaerator; 308: Demineralized water pipeline network; 309: Pipeline valves 310: Steam power generation unit; 4: Secondary heat exchange zone; 401: Industrial water heater; 402: Industrial water pipeline; 403: Hot water utilization pipeline; 5: Diversion steam supply zone; 501: Water mist nozzle; 502: Diversion baffle; 503: First circulation gas supply pipe; 504: Second circulation gas supply pipe; 6: Sintering machine; 601: Front fume hood; 602: Rear fume hood; 7: Circular cooler; 701: First stage air hood; 702: Second stage air hood; 703: Third stage air hood. Detailed Implementation

[0035] The technical solution of this utility model is illustrated below. The scope of protection of this utility model includes, but is not limited to, the following embodiments.

[0036] A system for upgrading and utilizing intermediate and low-temperature waste gas from an annular cooling system is disclosed. The system includes a shell and an inner cavity. A waste gas inlet 1, connected to the inner cavity, is located at the bottom of the shell. The inner cavity is divided from bottom to top into a series of interconnected heating and oxygen replenishment zones: a primary heat exchange zone 2, a primary heat exchange zone 3, a secondary heat exchange zone 4, and a diversion steam replenishment zone 5. The intermediate and low-temperature waste gas from the annular cooling system is converted into oxygen-enriched hot waste gas and oxygen-enriched steam-enriched hot waste gas, which can be directly used in the sintering process, after passing through the heating and oxygen replenishment zone 2, the primary heat exchange zone 3, the secondary heat exchange zone 4, and the diversion steam replenishment zone 5.

[0037] Preferably, the system also includes a sintering machine 6 and an annular cooler 7. According to the direction of the sintered material: a front fume hood 601 and a rear fume hood 602 are sequentially installed on the sintering machine 6, and a first-stage air hood 701, a second-stage air hood 702, and a third-stage air hood 703 are sequentially installed on the annular cooler 7. The outlets of the second-stage air hood 702 and the third-stage air hood 703 are connected to the exhaust gas inlet 1 via inlet pipes. The oxygen-enriched hot exhaust gas outlet of the diversion and steam replenishment zone 5 is connected to the inlet of the front fume hood 601 via a first circulating air supply pipe 503, and the oxygen-enriched and steam-enriched hot exhaust gas outlet of the diversion and steam replenishment zone 5 is connected to the inlet of the rear fume hood 602 via a second circulating air supply pipe 504. Preferably, an electric slide gate valve 101 is installed inside the exhaust gas inlet 1.

[0038] Preferably, on the sintering machine: the area covered by the front fume hood 601 is the 1 / 10 to 4 / 10 section of the material surface between the sintering ignition point and the sintering endpoint. The area covered by the rear fume hood 602 is the 5 / 10 to 8 / 10 section of the material surface between the sintering ignition point and the sintering endpoint.

[0039] As a preferred embodiment, in the annular cooler: the air outlet of the three-section shroud 703 is first connected to the bottom air inlet of the second section of the annular cooler located below the second-section shroud 702 through an air supply pipe, and the air outlet of the second-section shroud 702 is then connected to the exhaust gas inlet 1 through an air inlet pipe.

[0040] Preferably, an oxygen-enriched burner 201 is installed in the supplementary heating and oxygenation zone 2, and a combustible gas pipeline 202 and an oxygen-enriched gas pipeline 203 are connected to the oxygen-enriched burner 201.

[0041] Preferably, multiple oxygen-enriched burners 201 are installed in the supplementary heating and oxygenation zone 2, and each oxygen-enriched burner 201 is independently connected to a combustible gas pipeline 202 and an oxygen-enriched gas pipeline 203.

[0042] Preferably, within the primary heat exchange zone 3, a high-parameter steam superheater 301, a high-parameter steam evaporator 302, a high-parameter economizer 303, a deaerator evaporator 304, and a low-parameter economizer 305 are arranged sequentially from bottom to top. Outside the primary heat exchange zone 3, a steam drum 306, a deaerator 307, a demineralized water pipeline network 308, and a steam power generation unit 310 are arranged. The front end of the high-parameter steam superheater 301 is connected to the steam power generation unit 310 via pipes and valves, and its rear end is connected to the steam drum 306 via pipes. Both the front and rear ends of the high-parameter steam evaporator 302 are connected to the steam drum 306 via pipes. The front end of the high-parameter economizer 303 is connected to the deaerator 307 via pipes, and its rear end is connected to the steam drum 306 via pipes. Both the front and rear ends of the deaerator evaporator 304 are connected to the deaerator 307 via pipes. The front end of the low-parameter economizer 305 is connected to the demineralized water network 308 via a pipeline valve 309, and its rear end is connected to the deaerator 307 via a pipeline.

[0043] Preferably, an industrial water heater 401 is installed in the secondary heat exchange zone 4, and an industrial water pipeline 402 and a hot water utilization pipeline 403 are installed outside the secondary heat exchange zone 4. The front end of the industrial water heater 401 is connected to the industrial water pipeline 402, and its rear end is connected to the hot water utilization pipeline 403.

[0044] Preferably, a water mist nozzle 501 and a flow divider baffle 502 are provided in the flow divider replenishment zone 5. The top end of the flow divider baffle 502 is connected to the housing and divides the flow divider replenishment zone 5 into two horizontally parallel flow divider chambers. The water mist nozzle 501 is disposed in one of the flow divider chambers and has an oxygen-enriched and steam-enriched hot exhaust gas outlet at the top of the other flow divider chamber. Preferably, the top end of the flow divider baffle 502 is hinged to the housing, allowing the flow divider baffle 502 to swing horizontally to adjust the size of the two flow divider chambers.

[0045] Example 1

[0046] like Figures 1-2 As shown, a system for upgrading and utilizing intermediate and low-temperature waste gas from an annular cooling system is disclosed. The system includes a shell and an inner cavity. A waste gas inlet 1, connected to the inner cavity, is located at the bottom of the shell. The inner cavity is divided from bottom to top into a series of interconnected heating and oxygen replenishment zones: a primary heat exchange zone 2, a primary heat exchange zone 3, a secondary heat exchange zone 4, and a diversion steam replenishment zone 5. The intermediate and low-temperature waste gas from the annular cooling system is converted into oxygen-enriched hot waste gas and oxygen-enriched steam-enriched hot waste gas, which can be directly used in the sintering process, after passing through the heating and oxygen replenishment zone 2, the primary heat exchange zone 3, the secondary heat exchange zone 4, and the diversion steam replenishment zone 5.

[0047] Example 2

[0048] The system repeats Example 1, except that it also includes a sintering machine 6 and an annular cooler 7. According to the direction of the sintering material: a front fume hood 601 and a rear fume hood 602 are sequentially installed on the sintering machine 6; a first-stage air hood 701, a second-stage air hood 702, and a third-stage air hood 703 are sequentially installed on the annular cooler 7. The outlets of the second-stage air hood 702 and the third-stage air hood 703 are connected to the exhaust gas inlet 1 via inlet pipes. The outlet of the oxygen-enriched hot exhaust gas in the diversion and steam replenishment zone 5 is connected to the inlet of the front fume hood 601 via a first circulating air pipe 503; and the outlet of the oxygen-enriched and steam-enriched hot exhaust gas in the diversion and steam replenishment zone 5 is connected to the inlet of the rear fume hood 602 via a second circulating air pipe 504.

[0049] Example 3

[0050] The same method as Example 2 is used, except that an electric slide gate valve 101 is installed in the exhaust gas inlet 1.

[0051] Example 4

[0052] Repeat Example 3, except that on the sintering machine: the area covered by the front fume hood 601 is the 1 / 10 to 4 / 10 section of the material surface between the sintering ignition point and the sintering endpoint. The area covered by the rear fume hood 602 is the 5 / 10 to 8 / 10 section of the material surface between the sintering ignition point and the sintering endpoint.

[0053] Example 5

[0054] Repeat Example 4, except that on the annular cooler: the air outlet of the three-section hood 703 is first connected to the bottom air inlet of the second section of the annular cooler located below the second-section hood 702 through an air supply pipe, and the air outlet of the second-section hood 702 is then connected to the exhaust gas inlet 1 through an air inlet pipe.

[0055] Example 6

[0056] Example 5 is repeated, except that an oxygen-enriched burner 201 is provided in the supplementary heating and oxygenation zone 2, and a combustible gas pipeline 202 and an oxygen-enriched gas pipeline 203 are connected to the oxygen-enriched burner 201.

[0057] Example 7

[0058] Example 6 is repeated, except that multiple oxygen-enriched burners 201 are provided in the supplementary heating and oxygenation zone 2, and each oxygen-enriched burner 201 is independently connected to a combustible gas pipeline 202 and an oxygen-enriched gas pipeline 203.

[0059] Example 8

[0060] The embodiment 7 is repeated, except that within the primary heat exchange zone 3, a high-parameter steam superheater 301, a high-parameter steam evaporator 302, a high-parameter economizer 303, a deaerator evaporator 304, and a low-parameter economizer 305 are arranged sequentially from bottom to top. Outside the primary heat exchange zone 3, a steam drum 306, a deaerator 307, a demineralized water pipeline network 308, and a steam power generation unit 310 are arranged. The front end of the high-parameter steam superheater 301 is connected to the steam power generation unit 310 via pipes and valves, and its rear end is connected to the steam drum 306 via pipes. Both the front and rear ends of the high-parameter steam evaporator 302 are connected to the steam drum 306 via pipes. The front end of the high-parameter economizer 303 is connected to the deaerator 307 via pipes, and its rear end is connected to the steam drum 306 via pipes. Both the front and rear ends of the deaerator evaporator 304 are connected to the deaerator 307 via pipes. The front end of the low-parameter economizer 305 is connected to the demineralized water network 308 via a pipeline valve 309, and its rear end is connected to the deaerator 307 via a pipeline.

[0061] Example 9

[0062] The embodiment 8 is repeated, except that an industrial water heater 401 is installed in the secondary heat exchange zone 4, and an industrial water pipeline 402 and a hot water utilization pipeline 403 are installed outside the secondary heat exchange zone 4. The front end of the industrial water heater 401 is connected to the industrial water pipeline 402, and its rear end is connected to the hot water utilization pipeline 403.

[0063] Example 10

[0064] The embodiment 9 is repeated, except that a water mist nozzle 501 and a diversion baffle 502 are provided in the diversion steam replenishment zone 5. The top end of the diversion baffle 502 is connected to the housing and divides the diversion steam replenishment zone 5 into two horizontally parallel diversion chambers. The water mist nozzle 501 is located in one of the diversion chambers and has an oxygen-enriched and steam-enriched hot exhaust gas outlet at the top of the diversion chamber, while an oxygen-enriched hot exhaust gas outlet is located at the top of the other diversion chamber.

[0065] Example 11

[0066] The embodiment 10 is repeated, except that the top of the diversion baffle 502 is hinged to the housing, so that the diversion baffle 502 can swing in the horizontal direction to adjust the size of the two diversion chambers.

Claims

1. A system for upgrading of medium and low temperature exhaust gas of ring cooling, characterized in that: The system comprises a shell and an inner cavity; the bottom of the shell is provided with a waste gas inlet (1) communicating with the inner cavity; the inner cavity is divided into a heat and oxygen supplementing zone (2), a first heat exchanging zone (3), a second heat exchanging zone (4) and a shunt steam supplementing zone (5) in sequence from bottom to top; the medium and low temperature waste gas of the ring cooler passes through the heat and oxygen supplementing zone (2), the first heat exchanging zone (3), the second heat exchanging zone (4) and the shunt steam supplementing zone (5) in sequence and is converted into oxygen-rich hot waste gas and oxygen-rich steam-rich hot waste gas which can be directly used in the sintering process; the height of the shell is 1-300m.

2. The system of claim 1, wherein: The system further comprises a sintering machine (6) and a ring cooler (7); according to the movement direction of the sintering material: the front section hood (601) and the rear section hood (602) are sequentially arranged on the sintering machine (6), and the one section hood (701), the two section hood (702) and the three section hood (703) are sequentially arranged on the ring cooler (7); the air outlets of the two section hood (702) and the three section hood (703) are both communicated with the waste gas inlet (1) through air inlet pipes; the oxygen-rich hot waste gas outlet of the shunt steam supplementing zone (5) is communicated with the air inlet of the front section hood (601) through the first circulating gas pipe (503), and the oxygen-rich steam-rich hot waste gas outlet of the shunt steam supplementing zone (5) is communicated with the air inlet of the rear section hood (602) through the second circulating gas pipe (504).

3. The system of claim 2, wherein: An electric plug valve (101) is arranged in the waste gas inlet (1).

4. The system of claim 2, wherein: On the sintering machine: the area covered by the front section hood (601) is the first 1 / 10 to the fourth 1 / 10 of the material surface between the sintering ignition point and the sintering end point; the area covered by the rear section hood (602) is the fifth 1 / 10 to the eighth 1 / 10 of the material surface between the sintering ignition point and the sintering end point.

5. The system of claim 4, wherein: On the ring cooler: the air outlet of the three section hood (703) is communicated with the bottom air inlet of the second section of the ring cooler below the two section hood (702) through an air supply pipe, and the air outlet of the two section hood (702) is communicated with the waste gas inlet (1) through an air inlet pipe.

6. The system of any one of claims 1-5, wherein: An oxygen-rich burner (201) is arranged in the heat and oxygen supplementing zone (2), and a combustible gas pipeline (202) and an oxygen-rich gas pipeline (203) are connected to the oxygen-rich burner (201).

7. The system of claim 6, wherein: A plurality of oxygen-rich burners (201) are arranged in the heat and oxygen supplementing zone (2), and a combustible gas pipeline (202) and an oxygen-rich gas pipeline (203) are independently connected to each oxygen-rich burner (201).

8. The system of any one of claims 1-5, 7, wherein: The high-parameter steam superheater (301), the high-parameter steam evaporator (302), the high-parameter economizer (303), the deoxygenation evaporator (304) and the low-parameter economizer (305) are sequentially arranged from bottom to top in the primary heat exchange zone (3); the steam drum (306), the deaerator (307), the desalted water pipe network (308) and the steam power generation device (310) are arranged outside the primary heat exchange zone (3); the front end of the high-parameter steam superheater (301) is connected with the steam power generation device (310) through a pipeline and a valve, and the rear end thereof is connected with the steam drum (306) through a pipeline; the front end and the rear end of the high-parameter steam evaporator (302) are both connected with the steam drum (306) through pipelines; the front end of the high-parameter economizer (303) is connected with the deaerator (307) through a pipeline, and the rear end thereof is connected with the steam drum (306) through a pipeline; the front end and the rear end of the deoxygenation evaporator (304) are both connected with the deaerator (307) through pipelines; the front end of the low-parameter economizer (305) is connected with the desalted water pipe network (308) through a pipeline valve (309), and the rear end thereof is connected with the deaerator (307) through a pipeline.

9. The system of any of claims 1-5, 7, wherein: The industrial water heater (401) is arranged in the secondary heat exchange zone (4), and the industrial water pipe network (402) and the hot water utilization pipeline (403) are arranged outside the secondary heat exchange zone (4); the front end of the industrial water heater (401) is connected with the industrial water pipe network (402), and the rear end thereof is connected with the hot water utilization pipeline (403).

10. The system of any one of claims 1-5, 7, wherein: The water mist spray pipe (501) and the shunt baffle (502) are arranged in the shunt steam supplement zone (5); the top end of the shunt baffle (502) is connected with the shell and divides the shunt steam supplement zone (5) into two shunt chambers parallel in the horizontal direction, the water mist spray pipe (501) is arranged in one of the shunt chambers, and an oxygen-rich and steam-rich hot waste gas outlet is formed at the top of the shunt chamber, and an oxygen-rich hot waste gas outlet is formed at the top of the other shunt chamber.

11. The system of claim 10, wherein: The top end of the shunt baffle (502) is hinged with the shell, so that the shunt baffle (502) can swing in the horizontal direction to adjust the size of the two shunt chambers.

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