Sintering flue gas circulation seal cover spraying device, method and system

Abstract

The present invention provides a sintering flue gas circulation sealing hood spraying device, which includes: a flue gas sealing hood for being arranged above sintered ore and a process water pipeline for conveying process water. The process water pipeline includes a process water spraying pipe, and the process water spraying pipe is arranged inside the flue gas sealing hood. The present invention also provides a sintering flue gas circulation spraying method. In this method, the device as described above is used to spray process water on the sintered ore. The sintering flue gas circulation sealing hood spraying device provided by the present invention is provided with a process water spraying pipe inside it. The process water spraying pipe sprays according to the operating state of the sintering machine and the temperature of the sintered ore. The process water spraying pipe is arranged inside the flue gas sealing hood. It can not only realize the spraying of the sintered ore, but also the spraying of the process water is relatively uniform, ensuring the effect of preventing overburning of the sintered ore on the premise of saving water resources.

Description

Technical Field

[0001] The present invention relates to the technical field of sintering equipment, and more specifically, to a spray device for a sintering flue gas circulation seal cover, a sintering flue gas circulation spraying method, and a sintering machine flue gas internal and external combined circulation purification and waste heat utilization system. Background Art

[0002] The "sintering flue gas hierarchical circulation purification and waste heat utilization technology" (hereinafter referred to as "sintering flue gas circulation technology") is a flue gas circulation utilization technology that selects the flue gas of a specific wind box section to be led out from the sintering machine wind box according to the differences in the discharge characteristics (temperature, oxygen content, flue gas volume, pollutant concentration, etc.) of the sintering wind box flue gas, and finally circulates back to the flue gas seal cover and is introduced into the sintering material layer. In the sintering flue gas circulation technology, a series of complex physical and chemical reactions occur between the circulating flue gas and the sintering material layer, and finally the purpose of reducing the consumption of sintered solid fuel, improving the quality of the surface sintered ore, and improving the physical and chemical indexes such as the temperature uniformity and crushing strength of the sintered ore material layer is achieved. The sintering flue gas circulation technology realizes the coupling of multiple functions such as energy conservation, emission reduction, and production increase.

[0003] In the flue gas circulation system equipment, the flue gas seal cover plays a very important role, and the specific roles are as follows: 1. Collect the circulating flue gas and adjust the gas volume through the regulating valve at the top of the seal cover according to the different flue gas demand on the material surface in different areas of the sintering machine; 2. Adjust the parameters such as the selection position of the upstream wind box and the oxygen supplement amount of the system according to the flue gas parameters in the flue gas seal cover. Compared with the traditional sintering process, the sintering flue gas circulation technology has many advantages, but to better apply this technology to the existing sintering machines, there are still many practical problems that need to be solved and improved, which specifically include: 1. How to ensure that the sintering machine suddenly stops and prevent overburning of the sintered ore; 2. During the operation of the sintering machine, how to judge the overburning of the sintered ore caused by non-stop states and how to take measures.

[0004] At present, to prevent overburning of the sintered ore caused by shutdown, the general measures taken by the sintering machine production management personnel are: when the sintering machine stops, a large amount of process water is sprayed onto the sintered ore material surface with a plastic hose to achieve the purpose of quenching the sintered ore. This measure has the disadvantages of being extensive, disorderly, and completely relying on experience for operation, and there is a lack of effective management for the spraying consumption and control of the process water. In addition, since the flue gas circulation system is provided with a seal cover above the material surface, the above direct spraying process water measure cannot be implemented. The above problems are all common problems faced by the sintering flue gas circulation technology at present. Summary of the Invention

[0005] In summary, how to solve the problem that it is impossible to spray process water with a plastic hose due to the setting of the seal cover has become an urgent problem to be solved by those skilled in the art.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides a spray device for a sintering flue gas circulation seal cover, and the spray device for the sintering flue gas circulation seal cover includes:

[0008] A flue gas seal cover configured to be disposed above the sintered ore;

[0009] A process water pipeline for conveying process water, the process water pipeline including a process water spray pipe disposed within the flue gas seal cover.

[0010] Preferably, in the spray device for the sintering flue gas circulation seal cover provided by the present invention, the flue gas seal cover includes at least two seal cover units, and the adjacent seal cover units are detachably connected, and the process water spray pipe is disposed within each seal cover unit.

[0011] Preferably, in the spray device for the sintering flue gas circulation seal cover provided by the present invention, the seal cover unit includes a frame body and a cover surface, the frame body includes an arched top frame, and the cover surface is disposed on the top frame.

[0012] Preferably, in the spray device for the sintering flue gas circulation seal cover provided by the present invention, the frame body further includes a rectangular bottom frame, side brackets are disposed on both sides of the bottom frame along the length direction of the bottom frame, and the top frame is disposed on the top of the side brackets.

[0013] Preferably, in the spray device for the sintering flue gas circulation seal cover provided by the present invention, the process water pipeline includes a process water tank, a process water pump connected to the process water tank for pumping process water, a process water primary pipeline connected to the process water pump, a process water secondary pipeline connected to the process water primary pipeline for realizing the first diversion of the process water, a process water tertiary pipeline connected to the process water secondary pipeline for realizing the second diversion of the process water, and a process water quaternary pipeline connected to the process water tertiary pipeline, and one end of the process water quaternary pipeline extends into the seal cover unit and is connected to the process water spray pipe.

[0014] Preferably, in the spray device for the sintering flue gas circulation seal cover provided by the present invention, each seal cover unit corresponds to one process water quaternary pipeline; the process water quaternary pipelines disposed on the same flue gas seal cover are connected in parallel.

[0015] Preferably, in the spray device for the sintering flue gas circulation seal cover provided by the present invention, process water nozzles are disposed on the process water spray pipe.

[0016] Preferably, in the sintering flue gas circulation sealing hood spraying device provided by the present invention, the present invention further includes an automatic control system; the automatic control system includes a main control device, a temperature sensor that is signal-connected to the main control device and is used to obtain a temperature signal, a flow meter that is signal-connected to the main control device and is used to obtain the process water flow rate in the pipeline, and a regulating valve that is control-connected to the main control device; the temperature sensor is arranged on the flue gas sealing hood and is used to obtain the temperature on and around the surface of the sintered ore in the sintering furnace; the flow meter is arranged on the primary process water pipeline and the secondary process water pipeline; the regulating valve is arranged on the primary process water pipeline and the tertiary process water pipeline.

[0017] The present invention also provides a sintering flue gas circulation spraying method, and this sintering flue gas circulation spraying method uses the sintering flue gas circulation sealing hood spraying device as described above to spray process water on the sintered ore.

[0018] Preferably, in the sintering flue gas circulation spraying method provided by the present invention, the temperature on and around the surface of the sintered ore is obtained, and when the temperature is greater than the set threshold value, process water spraying is carried out; the operating state of the sintering machine is obtained, and when the sintering machine stops, process water spraying is carried out.

[0019] The present invention also provides a sintering machine flue gas internal and external combined cycle purification and waste heat utilization system. A smoke exhaust device is provided at the bottom of the sintering machine, and a flue gas sealing hood is arranged above the material surface of the sintering machine. The smoke exhaust device includes: a front machine wind box group, a middle machine wind box group, and a tail machine wind box group, and each wind box group includes several wind boxes; the system has: a flue gas external circulation subsystem and a flue gas internal circulation subsystem; the flue gas external circulation subsystem includes: a first main flue, a third main flue, and an external smoke exhaust flue. The first main flue is communicated with the front machine wind box group, the third main flue is communicated with the tail machine wind box group, the external smoke exhaust flue includes an external exhaust main flue, an external circulation flue, and an external exhaust branch flue. One end of the external exhaust main flue is respectively communicated with the first main flue and the third main flue, the other end of the external exhaust main flue is respectively communicated with the external circulation flue and the external exhaust branch flue, and the external exhaust branch flue is also communicated with the chimney; the flue gas internal circulation subsystem includes: a second main flue and an intake flue. The second main flue is communicated with the middle machine wind box group, one end of the intake flue is respectively communicated with the second main flue and the external circulation flue, and the other end of the intake flue is communicated with the flue gas sealing hood; the system also has: a process water pipeline for transporting process water. The process water pipeline includes a process water spraying pipe (38), and the process water spraying pipe is arranged in the flue gas sealing hood. The process water pipeline and the flue gas sealing hood are collectively called a spraying device, and the spraying device is the above-mentioned sintering flue gas circulation sealing hood spraying device.

[0020] Preferably, in the system provided by the present invention, the front blower group, the middle blower group, and the tail blower group of the sintering machine are arranged in sequence along the technological process direction of the sintering machine; an external circulation flue gas valve is arranged on the external circulation flue; the flue gas external circulation subsystem further includes: a denitration device, the inlet of the denitration device is communicated with the external discharge branch flue, and the outlet of the denitration device is communicated with the chimney.

[0021] Preferably, in the system provided by the present invention, along the flue gas flow direction, the second main flue is communicated with the inlet flue through a high-SO 2 flue; the system further includes: a gas-gas heat exchanger for transferring the heat of the flue gas conveyed by the third main flue to the flue gas conveyed by the high-SO 2 flue; a desulfurization reaction device arranged on the high-SO 2 flue for desulfurizing the flue gas conveyed by the high-SO 2 flue heated by the gas-gas heat exchanger and conveying the desulfurized flue gas to the inlet flue.

[0022] Preferably, in the system provided by the present invention, the system further includes: an internal circulation bypass flue, which is arranged in parallel with the desulfurization reaction device on the high-SO 2 flue.

[0023] Preferably, in the system provided by the present invention, the system further includes: a first blower for pumping the flue gas conveyed by the second main flue; a second blower arranged on the external discharge main flue for pumping the flue gas conveyed by the first main flue and the third main flue; and a dust collector for dust-removing treatment of the flue gas conveyed by the first main flue, the second main flue, and the third main flue; preferably, the number of the dust collectors is two, namely: a first dust collector for dust-removing treatment of the flue gas conveyed by the second main flue and located in front of the first blower and behind the desulfurization reaction device in the flue gas flow direction; and a second dust collector for dust-removing treatment of the flue gas conveyed by the first main flue and the third main flue and located in front of the second blower in the flue gas flow direction.

[0024] Preferably, in the system provided by the present invention, the system further includes: an ammonia supply device arranged on the inlet flue for inputting ammonia into the inlet flue.

[0025] Preferably, in the system provided by the present invention, the system further includes: a first flue gas mixer, two inlets of the first flue gas mixer are respectively communicated with the second main flue and the other end of the external circulation flue, and the outlet of the first flue gas mixer is communicated with one end of the inlet flue.

[0026] Preferably, in the system provided by the present invention, the system further includes: a first oxygen supply device, disposed on the intake flue, for supplying oxygen into the intake flue; or a second oxygen supply and mixing device, including: an oxygen buffer tank and a second flue gas mixer, the oxygen buffer tank is used for supplying oxygen, and the three intake ports of the second flue gas mixer are respectively communicated with the second main flue, the other end of the external circulation flue, and the outlet of the oxygen buffer tank, and the outlet of the second flue gas mixer is communicated with one end of the intake flue.

[0027] Preferably, in the system provided by the present invention, the intake flue is communicated with the flue gas sealing hood through a plurality of flue branches, and the plurality of flue branches are arranged at intervals along the length direction of the flue gas sealing hood. A regulating valve is arranged on the flue branch, and an oxygen concentration analyzer and a pressure detection device are arranged on the flue gas sealing hood corresponding to the flue branch.

[0028] Preferably, in the system provided by the present invention, the contents of nitrogen oxides and carbon oxides in the flue gas conveyed by the first main flue are greater than those in the flue gas conveyed by the second main flue and the flue gas conveyed by the third main flue; the content of sulfur dioxide in the flue gas conveyed by the second main flue is greater than those in the flue gas conveyed by the first main flue and the flue gas conveyed by the third main flue; the temperature of the flue gas conveyed by the third main flue is greater than those of the flue gas conveyed by the first main flue and the second main flue.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] The present invention provides a sintering flue gas circulation sealing hood spraying device, which includes: a flue gas sealing hood for being arranged above the sintered ore and a process water pipeline for conveying process water. The process water pipeline includes a process water spraying pipe, and the process water spraying pipe is arranged in the flue gas sealing hood. The present invention also provides a sintering flue gas circulation spraying method. In this method, the present invention uses the device as described above to spray process water on the sintered ore.

[0031] Through the above structural design, the sintering flue gas circulation sealing hood spraying device provided by the present invention and the sintering flue gas circulation spraying method are used to control the overburning of the sintered ore in the sintering machine. Compared with the prior art, it can achieve the following technical effects:

[0032] 1. In the case of a sudden shutdown of the sintering machine, the process water pump is signal-linked with the sintering machine, so as to realize automatic spraying for cooling. After the cooling is completed, the spraying can be automatically shut down according to the detected temperature signal. It has a high degree of automation, can quickly react to spray and cool down after the sintering machine shuts down, and can also automatically stop when the sintered ore cools down to a certain extent, saving water resources;

[0033] 2. Due to the increased automation level, during the operation of the sintering machine, the present invention can achieve remote control. Without going to the site, it can determine whether there is overburning in the sintered ore, reducing the labor intensity of the on-site inspection during the operation of the sintering machine. At the same time, the present invention can provide data reference for the overburning of the sintered ore, which is very helpful for preventing overburning;

[0034] 3. Compared with the extensive operation of manual spraying, the present invention can accurately control. According to the temperature parameters in each single sealing hood and the readings of the flow meters, the spraying amount of process water in each single sealing hood can be accurately controlled, so as to achieve the purpose of avoiding waste and saving costs;

[0035] 4. The single sealing hood is connected to the pipeline and between pipelines by flanges, which facilitates the layout and disassembly of the pipelines.

[0036] On this basis, the beneficial effects brought by the sintering machine flue gas internal and external combined cycle purification and waste heat utilization system provided by the embodiments of the present invention are as follows:

[0037] 1. The internal cycle process and the external cycle process are combined for the first time, giving full play to their respective advantages and avoiding their respective disadvantages.

[0038] 2. The internal cycle flue gas avoids taking flue gas from the wind box branch pipe, but directly takes flue gas from the main flue of the sintering machine, reducing the project volume and investment;

[0039] 3. Pure O 2 is used to supplement the oxygen content of the circulating flue gas, greatly improving the sintering flue gas circulation rate;

[0040] 4. SCR and SNCR denitrification are organically combined, and the temperature window in the sintering material layer is utilized to achieve SNCR denitrification of the sintering machine for the first time.

[0041] 5. The flue gas containing high SO 2 is enriched and removed inside the flue gas circulation system, saving the investment and operation costs of the subsequent desulfurization device. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The schematic drawings of the specification forming a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. Among them:

[0043] Figure 1 is a schematic diagram of the system composition of the sintering flue gas circulation sealing hood spraying device in an embodiment of the present invention;

[0044] Figure 2 is a schematic structural diagram of a single sealing hood in an embodiment of the present invention;

[0045] Figure 3This is the front view of a sealing cover monomer in an embodiment of the present invention.

[0046] Figure 4 This is a schematic structural diagram of a sintering machine flue gas internal and external combined cycle purification and waste heat utilization system provided by an embodiment of the present invention. In Figures 1 to 3 the corresponding relationship between the component names and the reference numerals is as follows:

[0047] Process water spray pipe 38, cover surface 39, top frame 40, bottom frame 41, side bracket 42, process water tank 43,

[0048] process water pump 44, process water first-stage pipeline 45, process water second-stage pipeline 46, process water third-stage pipeline 47, process water fourth-stage pipeline 48, flowmeter 49, regulating valve 50, temperature sensor 51.

[0049] In Figure 4 the corresponding relationship between the component names and the reference numerals is as follows:

[0050] 1 Sintering machine, 2 Gas-gas heat exchanger, 3 Desulfurization reaction device, 4 Bag filter, 5 First fan, 6 Second flue gas mixer, 7 Oxygen buffer tank, 8 Ammonia distributor, 9 Regulating valve, 10 Oxygen concentration analyzer, 11 Pressure detection device, 12 Flue gas sealing cover, 13 Electrostatic precipitator, 14 Second fan, 15 Hot air heating furnace, 16 Ammonia injection system, 17 SCR reactor, 18 Third fan, 19 Chimney, 20 First SO 2 Concentration analyzer, 21 Second SO2 concentration analyzer, 22 NO X Concentration analyzer, 23 CEMS analyzer, 24 Front-section flue of sintering machine, 25 High-SO 2 Flue, 26 Tail-end high-temperature flue, 27 Internal circulation bypass flue, 28 Main external discharge flue, 29 External circulation flue, 30 Bypass flue valve, 31 External circulation flue valve, 32 First main flue, 33 Second main flue, 34 Third main flue, 35 External discharge branch flue, 36 Intake flue, 37 Flue branch pipe. Detailed implementation manners

[0051] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present invention rather than limitation thereof. In fact, those skilled in the art will clearly understand that modifications and variations can be made to the present invention without departing from the scope or spirit thereof. For example, features shown or described as part of one embodiment can be used in another embodiment to yield yet another embodiment. Therefore, it is desirable that the present invention includes such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0052] In the description of the present invention, the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and does not require the present invention to be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. The terms "connected" and "coupled" used in the present invention should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be directly connected or indirectly connected through an intermediate component. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0053] Please refer to Figures 1 to 3 , wherein, Figure 1 is a schematic diagram of the system composition of the spray device for the sintering flue gas circulation seal hood in an embodiment of the present invention; Figure 2 is a structural schematic diagram of a seal hood monomer in an embodiment of the present invention; Figure 3 is the front view of a seal hood monomer in an embodiment of the present invention.

[0054] The object of the present invention is to provide a sintered ore anti-overburning solution applicable to the sintering flue gas circulation technology (a flue gas seal hood is provided in the sintering flue gas circulation technology). Based on the technical solution provided by the present invention, on the one hand, it can ensure that when the sintering machine suddenly stops, the sintered ore is prevented from overburning; on the other hand, when the sintering machine is operating normally, it can avoid the occurrence of the sintered ore overburning problem caused by other reasons than the sintering machine stopping.

[0055] For this reason, the present invention provides a sintering flue gas circulation seal hood spray device and a sintering flue gas circulation spraying method.

[0056] In the present invention, the specific structure of the sintering flue gas circulation seal hood spray device is as follows: it includes a flue gas seal hood, a process water pipeline, a process water spray pipe 38, a process water regulating valve 50 and a flow meter 49 arranged on the pipeline, and a process water pump 44 and a process water tank 43, etc.

[0057] Among them, the flue gas seal hood is composed of a plurality of seal hood monomers. The seal hood monomers are arranged in a straight line, and adjacent seal hood monomers are connected by bolts, which is convenient for the disassembly and assembly between the seal hood monomers.

[0058] The process water pipeline is divided into four levels, namely, the first-level process water pipeline 45 connected to the process water tank 43 (a process water pump 44 is provided between the process water tank 43 and the first-level process water pipeline 45), the second-level process water pipeline 46 connected to the first-level process water pipeline 45, multiple third-level process water pipelines 47 arranged in parallel and connected to the second-level process water pipeline 46, and the fourth-level process water pipeline 48 connected to the third-level process water pipeline 47 and leading to each sealing hood monomer. After the fourth-level process water pipeline 48 is introduced into the sealing hood monomer, it is connected to the process water spray pipe 38. The process water introduced by the fourth-level process water pipeline 48 flows into the process water spray pipe 38. Process water nozzles are provided on the process water spray pipe 38, and the process water is sprayed on the sintered ore in the flue gas sealing hood by the process water nozzles.

[0059] A temperature sensor 51 is provided at a position near the surface of the sintered ore at the lower part of the sealing hood monomer. The temperature sensor 51 monitors the temperature above the sintering machine material surface at any time to assist in judging whether overburning of the sintered ore occurs.

[0060] In the present invention, the judgment of the non-stop overburning situation of the sintered ore is mainly based on the following points: 1. The temperature displayed by the temperature sensor at the lower part near the material surface in the sealing hood continuously rises; 2. The flue gas temperature in the wind box below the material surface corresponding to this sealing hood continuously rises compared with the flue gas temperature during normal operation. Based on these two points, it can be basically judged that overburning of the sintered ore occurs.

[0061] According to the overburning situation of the sintered ore, in order to quantitatively spray the process water into the sealing hood monomer, flow meters 49 and regulating valves 50 are respectively provided on each level of the pipeline of the process water pipeline.

[0062] As the source of process water, a process water tank 43 is provided in the present invention. The process water tank 43 can be a concrete structure water tank, or a metal water tank, or a plastic water tank provided with a reinforcement device.

[0063] It should be noted that: in the present invention, according to the conventional design of pipeline connection, the pipelines in the present invention can be connected by a flange structure, or can be connected by an elbow (in a threaded manner).

[0064] In the present invention, the flow meter 49 is mainly provided on the first-level process water pipeline 45 and the second-level process water pipeline 46, and the regulating valve 50 is provided on the first-level process water pipeline 45 and the third-level process water pipeline 47. Of course, according to the improvement of the control accuracy requirements, the flow meter 49 and the regulating valve 50 can also be provided on the fourth-level process water pipeline 48.

[0065] For a single sealing cover, its specific structure is as follows: The single sealing cover includes a frame body and a cover surface 39. The frame body includes a bottom frame 41 with a rectangular frame structure. Side brackets 42 are arranged on both sides of the bottom frame 41 along the length direction of the bottom frame 41. An arched top frame 40 is arranged on the upper side of the side brackets 42. The bottom frame 41, the side brackets 42, and the top frame 40 can be made of metal profiles provided with an anti-corrosion coating. The bottom frame 41, the side brackets 42, and the top frame 40 are connected by welding, and a reinforcement device is arranged at the connection part, such as a reinforcement plate is arranged by welding. The cover surface 39 adopts a curved surface structure adapted to the structure of the top frame 40. The cover surface 39 can be made of a plastic sheet resistant to corrosion and high temperature, or a metal thin plate provided with an anti-corrosion coating.

[0066] Specifically, inside the bottom frame 41, that is, inside the rectangular frame, reinforcing bars are arranged on its diagonal. There are two reinforcing bars, and the two reinforcing bars cross to form an X-shaped structure.

[0067] Specifically, the side bracket 42 includes side bracket rods. The side bracket rods are arranged at intervals radially at the midpoints of the long sides of the bottom frame 41 (rectangular frame). Then, an arc-shaped rod arranged vertically is led out from the end of the bottom frame 41. One end of the side bracket rod is connected to the bottom frame 41, and the other end of the side bracket rod is connected to the arc-shaped rod.

[0068] The top frame 40 can adopt a truss structure. After the top frame 40 is integrally bent, it is arranged on the side bracket 42 and fixedly connected to the arc-shaped rod of the side bracket 42.

[0069] In the present invention, the arc-shaped rod can be made of angle iron. One side of the arc-shaped rod is connected to the side bracket rod, and the other side of the arc-shaped rod is connected to the top frame 40.

[0070] In order to reinforce the installation of the flue gas sealing cover, the present invention is provided with reinforcement bases at both ends of the bottom frame 41. The reinforcement bases are made of metal.

[0071] The fourth-stage process water pipeline 48 is horizontally inserted into the single sealing cover at the midpoint position in the width direction of the single sealing cover and at the position from one-half to two-thirds in the height direction. Then, a process water spray pipe 38 perpendicular and horizontally arranged is provided at its end. A plurality of process water nozzles are arranged on the process water spray pipe 38. The process water nozzles are arranged at intervals on the process water spray pipe 38.

[0072] A tee is arranged at one end of the fourth-stage process water pipeline 48 located inside the single sealing cover. A process water spray pipe 38 is arranged on each side of the fourth-stage process water pipeline 48 by the tee.

[0073] The present invention also provides a sintering flue gas circulation spraying method, which is realized based on the above-mentioned sintering flue gas circulation sealing hood spraying device, and its specific technological process is as follows: The process water pump 44 pumps process water out of the process water tank 43 and sends it into the first-stage process water pipeline 45. A flowmeter for the first-stage process water pipeline and a regulating valve for the first-stage process water pipeline are arranged on the first-stage process water pipeline 45 to accurately measure and control the total water output of the process water. In addition to adjusting the water volume with the regulating valve 50, the process water pump 44 is equipped with a variable-frequency motor, and the water volume can also be adjusted by changing the motor frequency, so as to achieve the purpose of saving electric energy.

[0074] The first-stage process water pipeline 45 is connected to a number of second-stage process water pipelines 46. In the present invention, preferably, the second-stage process water pipelines 46 are set to two. A flowmeter for the second-stage process water pipeline is arranged on one of the second-stage process water pipelines 46, and the flow rate of the other second-stage process water pipeline 46 is the difference between the readings of the flowmeter for the second-stage process water pipeline and the flowmeter for the first-stage process water pipeline. Therefore, there is no need to add a new flowmeter to the other second-stage process water pipeline 46, which simplifies the system composition and saves costs.

[0075] The second-stage process water pipelines 46 continue to branch and are connected to a total of four third-stage process water pipelines 47. On each of the four third-stage process water pipelines 47, a regulating valve for the third-stage process water pipeline is arranged to adjust the water inflow of a single sealing hood unit.

[0076] When the value of the temperature sensor 51 set for a certain sealing hood unit deviates greatly from the normal operating condition value (mainly high temperature), a larger amount of process water is input for spraying. If the value of the temperature sensor 51 of the sealing hood deviates slightly from the normal operating condition value, a smaller amount of process water is input for spraying, and the specific spraying amount is determined according to the actual situation during system debugging. In addition, a number of flowmeters for the third-stage process water pipelines are arranged on the third-stage process water pipelines 47 to measure and feedback signals to the regulating valve 50.

[0077] In a preferred embodiment of the present invention, each third-stage process water pipeline 47 is connected to three fourth-stage process water pipelines 48. One end of the fourth-stage process water pipeline 48 passes through the hood surface 39 of the sealing hood unit and is fixedly arranged inside the sealing hood unit, and then a process water spraying pipe 38 is arranged on each of the left and right sides of the fourth-stage process water pipeline 48 through a tee. A process water nozzle is arranged on the process water spraying pipe 38. The process water nozzle is a solid cone nozzle, and the material of the process water nozzle can be selected from stainless steel, carbon steel, high-temperature resistant plastics, etc. The spraying coverage rate should be ≥120% to ensure full coverage of the sintering machine material surface. Compared with manual large-area flooding cooling, nozzle spraying is more uniform on the one hand, and on the other hand, it will not cause the quenching of sintered ore and the decrease of the hardness of sintered ore.

[0078] To facilitate the disassembly and assembly of components such as pipelines at all levels, flowmeter 49, and regulating valve 50, several flanges are provided on the pipeline. In particular, one flange is provided on each side of the upper surface 39 of a single sealing cover unit.

[0079] The process water pump 44 is interlocked with the start / stop signal of the sintering machine, and the regulating valve 50 is interlocked with the start / stop signal of the process water pump 44. Once the sintering machine stops, the process water pump 44 starts immediately, and the regulating valve 50 opens accordingly, and water spraying starts inside the sealing cover. The water spraying amount and spraying duration are automatically adjusted according to the deviation value between the temperature displayed in real time by the temperature sensor 51 and the temperature under normal operating conditions. When the temperature is adjusted to the normal level, the water spraying stops.

[0080] During the operation of the sintering machine, when the deviation value between the temperature displayed in real time by the temperature sensor 51 and the temperature under normal operating conditions continuously increases, it can be preliminarily judged that the sintered ore is overburned. At this time, combined with the flue gas temperature of the corresponding air box below the sealing cover, it is determined whether the sintered ore is indeed overburned. After the final determination, the process water spraying device is started.

[0081] The sintering flue gas circulation spraying method provided by the present invention is realized by means of the sintering flue gas circulation sealing cover spraying device. It detects the temperature inside the sealing cover unit, especially near the sintered ore surface, and controls the process water spraying and spraying amount according to the detected temperature. It can achieve the purpose of preventing sintering problems during the normal operation of the sintering machine. The present invention can also control the process water spraying according to the operating state of the sintering machine, and can achieve the purpose of preventing sintering problems when the sintering machine stops. Compared with the traditional manual operation method of holding a pipe for rough, disorderly, and full-of-experience large-water flooding operation, the present invention has been greatly improved in terms of automation degree and spraying effect.

[0082] In the sintering flue gas circulation spraying method provided by the present invention, for the two states of the sintering machine, namely normal operation and shutdown, there are the following different spraying schemes.

[0083] When the sintering machine is operating normally, first, the temperature sensor 51 obtains the temperature of the sinter ore surface and its surrounding environment, and the temperature signal is sent to the main control device (the core component for realizing automatic control in the sintering flue gas circulation and sealing hood spraying device provided by the present invention). Different thresholds are set in the main control device according to different application scenarios. When the sintering machine is operating normally, the temperature sensor 51 obtains the temperature inside the sintering machine. If the temperature exceeds the threshold, the process water spraying is started. If the temperature does not exceed the threshold, but it is detected that the temperature of the sinter ore continues to rise. At this time, the temperature of the sintering machine wind box flue gas should be obtained again. If this temperature continues to rise relative to the preset threshold (i.e., the temperature during normal operation), it can be judged that there is an overburn phenomenon in the sinter ore, that is, the process water nozzle is controlled by combining these two sets of temperature signals. When the sintering machine suddenly stops, the operating state of the sintering machine is obtained. When the main control device judges that the sintering machine stops, it immediately controls the process water pump 44 to start, and the process water pump 44 sprays the process water in the process water tank 43 for shutdown spraying.

[0084] In the prior art, a plurality of wind boxes (i.e., smoke exhaust devices) are arranged at the bottom of the sintering machine, and the outlets of the wind boxes are communicated with the main flue of the sintering machine, so that the sintering machine discharges flue gas through the wind boxes. Due to the characteristics of the sintering process, the properties of the flue gas discharged from each wind box are different. On the basis of considering the pollutant components and temperature distribution characteristics of the flue gas discharged from each wind box, in the embodiments of the present application, the plurality of wind boxes are divided into: the front wind box group, the middle wind box group, and the tail wind box group, and each wind box group includes several wind boxes. Preferably, the plurality of wind boxes are sequentially divided along the process flow direction of the sintering machine.

[0085] Taking the example that the sintering machine is equipped with 23 wind boxes to illustrate the wind box group: the 23 wind boxes are numbered 1#, 2#,..., 22#, 23#, and are arranged in sequence along the process flow direction of the sintering machine (i.e., from the feeding end to the discharging end). The 1# - 3# wind boxes correspond to the head position, and the characteristics of the flue gas discharged from them are: high oxygen, low temperature, low dust, and low pollutants. This flue gas can be directly discharged into the atmosphere after dust removal; the 4# - 8# wind boxes correspond to the front section position, and the characteristics of the flue gas discharged from them are: high CO, NO x ; the 9# - 19# wind boxes correspond to the middle section position, and the characteristics of the flue gas discharged from them are: high SO 2; The 20#-23# bellows correspond to the tail position of the machine. The characteristics of the flue gas discharged from the outer row are: high temperature, and this flue gas can be directly discharged into the atmosphere after dust removal. Therefore, the 1#-8# bellows can be called the front-machine bellows group and connected to the first main flue 32; the 9#-19# bellows can be called the middle-machine bellows group and connected to the second main flue 33; the 20#-23# bellows can be called the tail-machine bellows group and connected to the third main flue 34. In other words, the main flue of the sintering machine is divided into three parts with non-communicating flue gases: the first main flue 32, the second main flue 33, and the third main flue 34. In other embodiments, other divisions of multiple bellows can also be made. For example, multiple bellows can be divided into: the head-machine bellows group, the front-section bellows group of the machine, the middle-machine bellows group, and the tail-machine bellows group. Among them, the head-machine bellows group and the front-section bellows group of the machine are combined into the front-machine bellows group. Corresponding to the aforementioned 23 bellows, the 1#-3# bellows can be called the head-machine bellows group and connected to the fourth main flue; the 4#-8# bellows can be called the front-section bellows group of the machine and connected to the first main flue 32. As long as it satisfies: the content of nitrogen oxides and carbon oxides in the flue gas transported by the first main flue 32 is greater than the content in the flue gas transported by the second main flue 33 and the third main flue 34, the content of sulfur dioxide in the flue gas transported by the second main flue 33 is greater than the content in the flue gas transported by the first main flue 32 and the third main flue 34, and the temperature of the flue gas transported by the third main flue 34 is greater than the temperature of the flue gas transported by the first main flue 32 and the second main flue, this embodiment does not limit this.

[0086] See Figure 1 , The embodiment of the present invention provides a sintering machine flue gas internal and external combined cycle purification and waste heat utilization system, which includes: a flue gas external circulation subsystem and a flue gas internal circulation subsystem.

[0087] The flue gas external circulation subsystem includes: a first main flue 32, a third main flue 34 and an external exhaust flue. One end of the first main flue 32 is connected to the outlets of each wind box in the front wind box group, and the other end is connected to the front section flue 24 of the sintering machine. One end of the third main flue 34 is connected to the outlets of each wind box in the rear wind box group, and the other end is connected to the rear high-temperature flue 26. The external exhaust flue includes: an external exhaust main flue 28, an external circulation flue 29 and an external exhaust branch flue 35. One end of the external main flue 28 is connected to the first main flue 32 and the third main flue 34 through the front flue 24 of the sintering machine and the high-temperature flue 26 at the rear of the machine, that is, the flue gas transported by the front flue 24 of the sintering machine and the flue gas transported by the high-temperature flue 26 at the rear of the machine are mixed and enter the external main flue 28, and the other end of the external main flue 28 is connected to one end of the external circulation flue 29 and one end of the external branch flue 35 respectively, and the other end of the external branch flue 35 is also connected to the chimney 19, and the other end of the external circulation flue 29 is connected to one end of the following intake flue 36, so as to form a flue gas external circulation path. In other words, the flue gas in the external flue has two flow paths, one is discharged into the atmosphere through the chimney 19, and the other is to enter the intake pipe 36 to realize the external circulation of flue gas. The flue gas internal circulation subsystem includes: the second main flue 33 and the intake flue 36. One end of the second main flue 33 is connected to the outlet of each wind box in the wind box group in the machine, and the other end is connected to the high SO 2 The flue 25 is connected, so that the high SO 2 Flue gas passes through high SO 2 The flue duct 25 is led out. Since this part of the flue gas is led out from the second main flue duct 33 belonging to the main flue of the sintering machine, that is, the flue gas is directly taken from the second main flue duct 33, thus avoiding the disadvantage of taking the flue gas from the wind box branch pipe, which can reduce the engineering workload and investment. One end of the air intake flue duct 36 is also connected to the high SO 2 The flue 25 is connected, and the other end of the air intake flue 36 is connected to the flue gas sealing cover 12, so as to form a flue gas internal circulation path. The flue gas sealing cover 12 is arranged above the material surface of the sintering machine, which can play a role in evenly distributing the flue gas, and can evenly distribute the flue gas to the material surface of the middle and rear sections of the sintering machine trolley to participate in the sintering process, such as the sintering machine material surface corresponding to the 15#~23# wind boxes. The system also has: a process water pipeline for conveying process water, the process water pipeline includes a process water spray pipe 38, the process water spray pipe is arranged in the flue gas sealing cover, the process water pipeline and the flue gas sealing cover are collectively referred to as a spray device, and the spray device is the above-mentioned sintering flue gas circulation sealing cover spray device.

[0088] By providing the first main flue 32, the third main flue 34 and the external exhaust flue as well as the second main flue 33 and the air intake flue 36, the internal circulation process of the sintering machine flue gas can be combined with the external circulation process to achieve the comprehensive advantages of the two technologies and maximize their strengths while minimizing their weaknesses.

[0089] The sintering machine flue gas contains a certain concentration of NO xPollutants. To meet the emission standards, the flue gas external circulation subsystem further includes: a denitration device for removing nitrogen oxides from the flue gas, whose inlet is connected to the other end of the external discharge branch flue 35, and the outlet is connected to the chimney 19, so that the flue gas can reach the ultra-low emission level and then be discharged into the atmosphere by the chimney 19. Specifically, the denitration device includes: a heating furnace, an ammonia injection system 16, an SCR (Selective Catalytic Reduction) reactor 17, and a third fan 18 that are sequentially arranged on the external discharge branch flue along the denitration process flow. The heating furnace is used to heat the flue gas entering the external discharge branch flue 35, and it can be a hot air heating furnace 15. The ammonia injection system 16 is arranged after the heating furnace and is used to inject ammonia into the external discharge branch flue 35 and mix it with the heated flue gas. The SCR reactor 17 is arranged after the ammonia injection system 16 and is used to carry out denitration reaction on the flue gas entering it. The third fan 18 is arranged after the SCR reactor 17 and is used to provide pumping power for the flue gas.

[0090] To adapt to different working conditions, an external circulation flue valve 31 is arranged on the external circulation flue 29. During normal use, this valve is in the open state. According to different demands for flue gas, the opening degree of this valve can be adjusted. When this valve is in the closed state, the flue gas transported in the external discharge main flue 28 does not enter the intake flue 36 and is only discharged by the chimney 19.

[0091] Since the flue gas discharged from the chimney 19 directly enters the atmosphere, to make the pollutant indexes of the flue gas reach the emission standards, this system further includes: a CEMS (Continuous Emission Monitoring System) analyzer 23, which is arranged on the external discharge branch flue 35 close to the chimney 19. For example, it can be located on the external discharge branch flue 35 between the following third fan 18 and the chimney 19. Since the flue gas transported in the first main flue 32 and the third main flue 34 is low-sulfur flue gas and there is basically no situation of SO 2 exceeding the standard, therefore, the CEMS analyzer 23 is mainly used to monitor NO X and dust concentration. When the NO X concentration exceeds the standard, it is necessary to increase the parameters in the denitration device, such as the ammonia injection amount, to make the flue gas meet the standard; when the dust concentration exceeds the standard, it is necessary to adjust the operating parameters of the following second dust collector to make the flue gas meet the standard. To improve the denitration efficiency, a NO x concentration analyzer 22 is arranged on the external discharge branch flue 35 in front of the SCR reactor 17 and is used to monitor the NO x concentration of the flue gas entering the SCR reactor 17. In this way, the ammonia injection amount of the ammonia injection system 16 can be determined according to this concentration. When the NO xWhen the concentration remains high, the ammonia injection amount of the ammonia injection system 16 is increased; otherwise, the injection amount is decreased.

[0092] From the high SO 2 The flue gas temperature led out from the flue 25 can reach 160 - 170 °C. Generally, the desulfurization reaction of the desulfurization reaction device 3 requires a certain reaction temperature, such as above 220 °C. And the flue gas temperature conveyed by the third main flue 34 is relatively high. In order to make full use of the waste heat of this part of the flue gas and carry out desulfurization treatment on the flue gas conveyed by the second main flue 33, this system further includes: a gas-gas heat exchanger 2 and a desulfurization reaction device 3. The gas-gas heat exchanger 2 is used to utilize the heat of the flue gas conveyed by the third main flue 34 to heat the flue gas conveyed by the high SO 2 flue 25, that is, the flue gas conveyed by the high SO 2 flue 25 and the flue gas conveyed by the tail-end high-temperature flue 26 are exchanged heat in the gas-gas heat exchanger 2. After heat exchange, the reaction temperature can be reached. Specifically, the heat source inlet and heat source outlet of the gas-gas heat exchanger 2 are arranged on the tail-end high-temperature flue 26 so that the flue gas conveyed by the tail-end high-temperature flue 26 enters the gas-gas heat exchanger 2 from the heat source inlet and flows out from the heat source outlet after heat exchange; the cold source inlet and cold source outlet of the gas-gas heat exchanger 2 are arranged on the high SO 2 flue 25 so that the flue gas conveyed by the high SO 2 flue 25 enters the gas-gas heat exchanger 2 from the cold source inlet and flows out from the cold source outlet after heat exchange. The desulfurization reaction device 3 is used to carry out desulfurization treatment on the flue gas conveyed by the high SO 2 flue 25 after being heated by the gas-gas heat exchanger 2 and convey the desulfurized flue gas to the intake flue 36. It is arranged on the high SO 2 flue 25. In this way, the end treatment of sintering flue gas pollutants can be advanced to the process control. Inside this system, the flue gas containing high SO 2 is enriched, and the desulfurization reaction device 3 is embedded inside this system, saving the investment and operation costs of configuring a desulfurization reaction device (or desulfurization device) in the subsequent flue gas purification system. In order to effectively monitor the operation of the desulfurization reaction device 3, this system further includes: a second SO 2 concentration analyzer 21, which is used to monitor the SO 2 concentration in the flue gas after being treated by the desulfurization reaction device 3. It is arranged on the high SO 2 flue 25 after the desulfurization reaction device 3, for example, it can be on the high SO 2 flue 25 after the following first blower 5. The first blower 5 is located after the desulfurization reaction device 3. When the monitored SO 2 concentration value continuously remains higher than the normal operating value under normal conditions, an alarm message indicating the failure of the desulfurization reaction device 3 is prompted, and the maintenance personnel need to check whether the desulfurization reaction device 3 fails accordingly.

[0093] When the desulfurization reaction device 3 needs to be overhauled, it is usually shut down for maintenance. At this time, in order to still maintain the normal operation of the flue gas internal circulation subsystem, this system further includes: an internal circulation bypass flue 27, which is arranged in parallel with the desulfurization reaction device 3 on the high-SO 2 flue 25, that is, on the high-SO 2 flue 25 between the cold source outlet of the gas-gas heat exchanger 2 and one end of the intake pipe 36, an internal circulation bypass flue 27 is arranged in parallel. The internal circulation bypass flue 27 is provided with a bypass flue valve 30. When this system operates normally, this valve is in the closed state; when this system needs to be overhauled, this valve is in the open state. On this basis, a desulfurization flue valve can be arranged in front of the desulfurization reaction device 3. At this time, this valve is in the closed state.

[0094] The SNCR (Selective Non-Catalytic Reduction) denitration reaction temperature range can be 900°C - 1100°C, and the temperature of the sinter ore layer can be 1000°C - 1100°C. The temperature ranges of the two are the same, making the denitration reaction temperature window. In order to further remove NO x , this system further includes: an ammonia supply device for inputting ammonia into the intake flue, which is arranged on the intake flue 36, such as near the flue gas seal cover 12 side. In this way, the flue gas containing NO x reacts with NH 3 in the sintering material layer to carry out the SNCR reaction, realizing the organic combination of SCR and SNCR denitration and improving the removal rate of NO x . Specifically, the ammonia supply device includes: an ammonia tank and an ammonia distributor 8. The ammonia tank is communicated with the intake flue 36, and the ammonia distributor 8 is arranged in the intake flue 36 for making the ammonia entering the intake flue 36 from the ammonia tank evenly distributed in the flue gas, so as to facilitate the full mixing with the flue gas.

[0095] Generally, the flue gas contains dust. In order to reduce the adverse effects of dust on the flue and equipment and the pollution to the atmosphere, this system further includes: a dust collector for dust-removing treatment of the flue gas conveyed by the first main flue 32, the second main flue 33 and the third main flue 34. Preferably, the number of dust collectors is two, and the two dust collectors are divided into: a first dust collector and a second dust collector. The first dust collector is used for dust-removing treatment of the flue gas conveyed by the second main flue 33, and it can be arranged on the high-SO 2On the flue 25. In application, the first dust collector can be the bag filter 4, and the dust removal efficiency of the bag filter 4 is above 99.5%, which can remove most of the particulate matters in the flue gas. Since the bag filter 4 usually needs to be shut down for maintenance when it needs to be overhauled, in order to still maintain the normal operation of the flue gas internal circulation subsystem, the above-mentioned internal circulation bypass flue 27 is arranged in parallel with the desulfurization reaction device 3 and the bag filter 4 on the high SO 2 On the flue 25, that is, on the high SO between the cold source outlet of the gas-gas heat exchanger 2 and the inlet of the first fan 5 2 An internal circulation bypass flue 27 is arranged in parallel on the flue 25. The second dust collector is used for dust removal of the flue gas conveyed by the first main flue 32 and the third main flue 34, and it can be arranged on the external discharge main flue 28. In application, the second dust collector can be the electrostatic precipitator 13. In other embodiments, the first dust collector can also be used for dust removal of the flue gas conveyed by the first main flue 32 and the second main flue 33, and it is arranged on the intake flue 36 for dust removal of the mixed flue gas, and the mixed flue gas is the flue gas after mixing the flue gas conveyed by the external circulation flue 29 and the flue gas conveyed by the high SO 2 Flue gas conveyed by the flue 25. The second dust collector is used for dust removal of the flue gas conveyed by the third main flue 34, and it is arranged on the external discharge branch flue 35. This embodiment does not limit this.

[0096] In order to improve the flow power of the flue gas, the system further includes: a first fan 5 and a second fan 14. The first fan 5 is used for pumping the flue gas conveyed by the second main flue 33, and it can be arranged behind the first dust collector in the flue gas flow direction. The second fan 14 is used for pumping the flue gas conveyed by the first main flue 32 and the third main flue 34, and it can be arranged on the external discharge main flue 28 in the flue gas flow direction and behind the second dust collector.

[0097] In order to enable the two flue gases to be fully mixed, the system further includes: a first flue gas mixer, which has two inlet ports and one outlet port. The two inlet ports are respectively the first inlet port and the second inlet port. The first inlet port is communicated with the high SO 2 Flue 25, the second inlet port is communicated with the other end of the external circulation flue 29, and this outlet port is communicated with one end of the intake flue 36. Specifically, the first flue gas mixer includes: a cylinder body and an outlet straight pipe. Two inlet ports are arranged on the upper part of the cylinder body. The outlet straight pipe is arranged in the cylinder body and is spaced from the cylinder body in the radial direction of the cylinder body to form a mixing interval. The top end of the outlet straight pipe is located outside the cylinder body for the output of the flue gas, and the bottom end of the outlet straight pipe is spaced from the bottom of the cylinder body to form a flow gap. The first inlet port is communicated with the high SO 2The flue 25 is connected, the second air inlet is connected to the other end of the outer circulation flue 29, and the rotation directions of the flue gases entering the cylinder body from the first air inlet and the second air inlet are the same, such as counterclockwise or clockwise, so that the two flue gases first rotate downward and then discharge upward. In this way, the mixing effect of the flue gases is enhanced, and the dust can also be thrown onto the inner wall of the cylinder body, enhancing the dust removal effect. The way the flue gas enters the cylinder body in each flue can be a tangential way or an arc way, and this embodiment does not limit this. A ash hopper is arranged at the bottom of the cylinder body, and the large end of the ash hopper is connected to the bottom of the cylinder body.

[0098] To increase the oxygen content in the flue gas, the system further includes an oxygen supply device, which is arranged on the intake flue 36 and is used to supply oxygen into the intake flue 36, thereby increasing the flue gas circulation rate and enabling the flue gas circulation rate to be increased to more than 65%. Generally, the oxygen supply device includes: an oxygen buffer tank 7 and an oxygen distributor. To reduce the number of devices and make the system structure simple, the system also includes: an oxygen buffer tank 7 and a second flue gas mixer 6. The oxygen buffer tank 7 is used to supply oxygen. The second flue gas mixer 6 has three air inlets and one air outlet. The three air inlets are the first air inlet, the second air inlet and the third air inlet respectively. The first air inlet is connected to the high SO 2 flue 25, the second air inlet is connected to the other end of the outer circulation flue 29, the third air inlet is connected to the oxygen buffer tank 7, and the air outlet is connected to one end of the intake flue 36. The specific structure of the second flue gas mixer 6 can be improved on the basis of the structure of the above first mixer. For example, an additional air inlet, that is, the third air inlet, is added to the cylinder body, and the other structures are the same.

[0099] The intake flue 36 is connected to the flue gas sealing cover 12 through a plurality of flue branches 37. The plurality of flue branches 37 are arranged at intervals along the length direction of the flue gas sealing cover 12, which is beneficial to evenly distribute the flue gas on the sintering machine material surface. A regulating valve 9 is arranged on each flue branch 37. According to the difference in the air permeability of the material layer and the gas demand in different sintering machine areas, the opening degree of the regulating valve is adjusted to keep the flue gas pressure stable in the flue gas sealing cover 12 and maintain a slightly negative pressure state to prevent the flue gas from leaking. The slightly negative pressure range can be -150 Pa to 0 Pa. An oxygen concentration analyzer 10 and a pressure detection device 11 are arranged on the flue gas sealing cover 12 corresponding to the flue branch 37. If the number of flue branches 37 is 4, 4 oxygen concentration analyzers 10 and 4 pressure detection devices 11 can be arranged in total to facilitate accurate monitoring of the oxygen content and flue gas pressure in each area and provide monitoring parameters for the normal operation of the system.

[0100] The following takes the configuration of 23 wind boxes (numbered 1# to 23# in sequence along the process flow direction) for the sintering machine as an example to illustrate the usage method of this system, which is specifically as follows:

[0101] The main flue of the sintering machine is divided into three parts with non - communicating flue gases, namely: the first main flue 32 corresponding to the 1# - 8# wind boxes, the second main flue 33 corresponding to the 9# - 19# wind boxes, and the third main flue 34 corresponding to the 20# - 23# wind boxes. The flues for conveying flue gases also include: the front - section flue 24 of the sintering machine, the high - SO 2 flue 25, the high - temperature flue 26 at the machine tail, the internal - circulation bypass flue 27, the main external - discharge flue 28, the external - circulation flue 29, and the external - discharge branch flue 35. The equipment involved in the internal - circulation process includes: the gas - gas heat exchanger 2, the desulfurization reaction device 3, the bag filter 4, the first fan 5, the second flue - gas mixer 6, the oxygen buffer tank 7, the ammonia distributor 8, the flue - gas seal cover 12, etc. The equipment involved in the external - circulation process includes: the electrostatic precipitator 13, the second fan 14, the SCR reactor 17, the third fan 18, etc.

[0102] The flue gas has two paths: The first - path flue gas, the high - SO 2 flue gas is led out through the high - SO 2 flue 25 connected to the second main flue 33, first passes through the gas - gas heat exchanger 2 for heat exchange with the high - temperature flue gas at the machine tail. After heat exchange, the high - SO 2 flue gas then sequentially passes through the desulfurization reaction device 3, the bag filter 4, the first fan 5, and then mixes with the other part of the flue gas described below in the second flue - gas mixer 6. The mixed flue gas then sequentially passes through the ammonia distributor 8 and the flue - gas seal cover 12 and reaches the sintering surface of the sintering machine to participate in the sintering process.

[0103] The second - path flue gas, after the flue gas led out from the front - section flue 24 of the sintering machine connected to the first main flue 32 and the high - temperature flue gas led out from the high - temperature flue 26 at the machine tail connected to the third main flue 34 converge, enters the electrostatic precipitator 13 for dust removal, passes through the main external - discharge flue 28, and then a part of it sequentially passes through the second fan 14, the hot - air heating furnace 15, the ammonia injection system 16, the SCR reactor 17, the third fan 18, and the chimney 19 for external discharge.

[0104] Through the above - mentioned structural design, the sintering flue - gas circulation seal - cover spraying device provided by the present invention and the application of the sintering flue - gas circulation spraying method can control the over - sintering of sintered ore in the sintering machine. Compared with the prior art, it can achieve the following technical effects:

[0105] 1. In the case of a sudden shutdown of the sintering machine, the process water pump is interlocked with the signal of the sintering machine, so as to realize automatic spraying for cooling. After the cooling is completed, it can also automatically close the spraying according to the detected temperature signal. Its automation degree is high, it can quickly react to spray and cool after the sintering machine shuts down, and moreover, it can automatically stop after the sintered ore cools to a certain degree, saving water resources;

[0106] 2. Due to the increased automation level, during the operation of the sintering machine, the present invention can achieve remote control. Without going to the site, it can determine whether there is overburning in the sintered ore, reducing the labor intensity of the on-site inspection during the operation of the sintering machine. At the same time, the present invention can provide data reference for the overburning of the sintered ore, which is of great help for preventing overburning;

[0107] 3. Compared with the extensive operation of manual spraying, the present invention can be accurately controlled. According to the temperature parameters in each sealing hood monomer and the readings of the flow meters, the spraying amount of process water in each sealing hood monomer can be accurately controlled, so as to achieve the purpose of avoiding waste and saving costs;

[0108] 4. The sealing hood monomers are connected to the pipelines and between the pipelines by flanges, which facilitates the layout and disassembly of the pipelines.

[0109] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, and simplifications made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A sintering flue gas circulation seal cover spraying device, characterized in that, it includes: A flue gas seal cover for being arranged above the sintered ore; A process water pipeline for transporting process water, the process water pipeline includes a process water spray pipe (38), and the process water spray pipe is arranged inside the flue gas seal cover; An exhaust device, the exhaust device includes: a front-of-machine wind box group, a middle-of-machine wind box group and a tail-of-machine wind box group, and each wind box group includes several wind boxes; A flue gas external circulation subsystem and a flue gas internal circulation subsystem; The flue gas external circulation subsystem includes: a first main flue, a third main flue and an external exhaust flue, the first main flue is communicated with the front-of-machine wind box group, the third main flue is communicated with the tail-of-machine wind box group, the external exhaust flue includes an external exhaust main flue, an external circulation flue and an external exhaust branch flue, one end of the external exhaust main flue is respectively communicated with the first main flue and the third main flue, the other end of the external exhaust main flue is respectively communicated with the external circulation flue and the external exhaust branch flue, and the external exhaust branch flue is also communicated with the chimney; The flue gas internal circulation subsystem includes: a second main flue and an intake flue, the second main flue is communicated with the middle-of-machine wind box group, one end of the intake flue is respectively communicated with the second main flue and the external circulation flue, and the other end of the intake flue is communicated with the flue gas seal cover; The flue gas seal cover includes at least two seal cover units, and the adjacent seal cover units are detachably connected, and the process water spray pipe is arranged inside each seal cover unit; Process water nozzles are arranged on the process water spray pipe.

2. The sintering flue gas circulation seal cover spraying device according to claim 1, characterized in that, The seal cover unit includes a frame body and a cover surface (39), the frame body includes an arched top frame (40), and the cover surface is arranged on the top frame.

3. The sintering flue gas circulation seal cover spraying device according to claim 2, characterized in that, The frame body also includes a rectangular bottom frame (41), side brackets (42) are arranged on both sides of the bottom frame along the length direction of the bottom frame, and the top frame is arranged on the top of the side brackets.

4. The sintering flue gas circulation seal cover spraying device according to claim 1, characterized in that, The process water pipeline includes a process water tank (43), a process water pump (44) connected to the process water tank for pumping process water, a process water first-stage pipeline (45) connected to the process water pump, a process water second-stage pipeline (46) connected to the process water first-stage pipeline for realizing the first shunt of process water, a process water third-stage pipeline (47) connected to the process water second-stage pipeline for realizing the second shunt of process water, and a process water fourth-stage pipeline (48) connected to the process water third-stage pipeline, and one end of the process water fourth-stage pipeline extends into the seal cover unit and is connected to the process water spray pipe.

5. The sintering flue gas circulation seal cover spraying device according to claim 1, characterized in that, One process water fourth-stage pipeline is correspondingly arranged for each seal cover unit; The four - stage process water pipelines provided on the same flue gas seal cover are arranged in parallel.

6. The sintering flue gas circulation seal cover spraying device according to claim 4, characterized in that, it further includes an automatic control system; The automatic control system includes a main control device, a temperature sensor (51) signal - connected to the main control device for obtaining temperature signals, a flowmeter (49) signal - connected to the main control device for obtaining the flow rate of process water in the pipeline, and a regulating valve (50) control - connected to the main control device; The temperature sensor is arranged on the flue gas seal cover and is used to obtain the temperature on the surface and around the sintered ore in the sintering furnace; The flowmeter is arranged on the first - stage process water pipeline and the second - stage process water pipeline; The regulating valve is arranged on the first - stage process water pipeline and the third - stage process water pipeline.

7. A sintering flue gas circulation spraying method, characterized in that, using the sintering flue gas circulation seal cover spraying device according to any one of claims 1 to 6 to spray process water on the sintered ore; obtaining the temperature on the surface and around the sintered ore, and when the temperature is greater than the set threshold value, performing process water spraying; obtaining the operating state of the sintering machine, and when the sintering machine stops, performing process water spraying.

8. A sintering machine flue gas internal and external combined cycle purification and waste heat utilization system, with a smoke exhaust device provided at the bottom of the sintering machine, and a flue gas seal cover provided above the material surface of the sintering machine, characterized in that, the smoke exhaust device includes: a front - machine wind box group, a middle - machine wind box group, and a tail - machine wind box group, and each wind box group contains several wind boxes; the system has: a flue gas external circulation subsystem and a flue gas internal circulation subsystem; The flue gas external circulation subsystem includes: a first main flue, a third main flue, and an external smoke exhaust flue. The first main flue is communicated with the front - machine wind box group, the third main flue is communicated with the tail - machine wind box group. The external smoke exhaust flue includes an external exhaust main flue, an external circulation flue, and an external exhaust branch flue. One end of the external exhaust main flue is respectively communicated with the first main flue and the third main flue, the other end of the external exhaust main flue is respectively communicated with the external circulation flue and the external exhaust branch flue, and the external exhaust branch flue is also communicated with the chimney; The flue gas internal circulation subsystem includes: a second main flue and an intake flue. The second main flue is communicated with the middle - machine wind box group, one end of the intake flue is respectively communicated with the second main flue and the external circulation flue, and the other end of the intake flue is communicated with the flue gas seal cover; The system also has: a process water pipeline for transporting process water. The process water pipeline includes a process water spraying pipe (38), and the process water spraying pipe is arranged inside the flue gas seal cover. The process water pipeline and the flue gas seal cover are collectively called a spraying device; The spraying device is the sintering flue gas circulation seal cover spraying device according to any one of claims 2 to 6.

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