CN102251094B - Heat accumulating type soaking pit furnace for burning low-heat value gas - Google Patents

Abstract

The invention discloses a regenerative soaking furnace for burning gas with low calorific value. The soaking furnace includes a furnace body and a furnace cover, wherein the soaking furnace is equipped with a low-temperature heating system for heating with high calorific value gas and A regenerative high-temperature heating system using low-calorific-value gas for heating, and the low-temperature heating system shares air supply and smoke exhaust pipelines with the regenerative high-temperature heating system. The present invention adopts a high-temperature and low-temperature dual heating system. Since the ignition temperature of blast furnace gas is relatively high, the heating of wide and thick plates or steel ingots requires heating and heat preservation in various temperature sections. In order to meet the needs of low-temperature heating, in addition to the regenerative high-temperature heating system, the present invention also sets up a set of low-temperature heating system, which shares the air supply and smoke exhaust pipelines with the regenerative combustion high-temperature heating system, which can realize different Shutdown switch.

Description

Regenerative soaking furnace burning low calorific value gas

technical field

The technology of the present invention relates to a soaking furnace in the metallurgical industry, such as a soaking furnace used in the production of wide and thick plates and heating steel ingots, in particular to a kind of low-calorific-value gas (such as blast furnace gas) that uses high-temperature heat storage combustion technology and uses high-temperature And low-temperature heating double heating system regenerative soaking furnace.

Background technique

The soaking furnace is a traditional furnace structure that first appeared at the end of the 19th century and is used for soaking the steel ingots after demoulding. In recent years, the large-scale and integrated rise of the shipbuilding industry and manufacturing industry has promoted the demand for the rolling and processing industry of wide and thick plates, and the soaking furnace can meet the heating needs of large-sized steel billets required by the wide and thick plate production line, so, In the new wide and thick plate production line, most of the heating equipment adopts or reserves the heating process of the soaking furnace.

Since blast furnace gas cannot organize combustion at low temperature (<750° C.), the existing soaking furnaces using blast furnace gas usually cannot meet the requirements of the low-temperature heating process of soaking furnaces.

In addition, when pure blast furnace gas is used for heating the soaking furnace, if it is not preheated, it cannot be directly used for heating the steel ingot at 1320°C. The previous preheating method was a regenerative soaking furnace using a clay heat exchanger. Due to its large size and high air leakage rate, this technology has been eliminated.

Contents of the invention

The technical problem solved by the present invention is to provide a regenerative soaking furnace for burning low-calorific gas, which can meet the heating temperature requirements of the soaking furnace.

The technical solution of the present invention is: a regenerative soaking furnace for burning low calorific value gas. A low-temperature heating system and a regenerative high-temperature heating system using low-calorific-value gas for heating, and the low-temperature heating system and the regenerative high-temperature heating system share air supply and smoke exhaust pipelines.

The regenerative soaking furnace for burning low-calorific-value gas as described above, wherein the high-temperature heating system includes first and second high-temperature channel combinations and switching mechanisms arranged in pairs on both sides of the soaking furnace, and the first 1. The second high-temperature channel combination includes an air channel structure and a low calorific value gas channel structure arranged on the same side. The air channel is connected to the air supply pipeline and the smoke exhaust pipeline. The low calorific value gas channel is connected to the low calorific value gas pipe The air passage structure and the low calorific value gas passage structure both include a relatively independent heat storage box outside the soaking furnace body, and the switching mechanism makes the first and second high temperature The channel combination alternates as a combustion channel combination or a smoke exhaust channel combination.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein, the air channel structure and the low-calorific gas channel structure both include a high-temperature gas channel, the heat storage box and a low-temperature gas channel, and the heat storage box It includes a heat storage box and a heat storage body arranged inside, one end of the heat storage box is provided with the low-temperature gas passage connected to the pipeline, and the other end is provided with the high-temperature gas passage connected with the furnace body The side wall on one side of the furnace body is provided with air spouts and low calorific value gas spouts respectively connected with the air and low calorific value gas passage structures of the first high temperature passage combination, and the side wall on the other side is provided with Air nozzles and low calorific value gas nozzles respectively connected with the air and low calorific value gas channel structures respectively combined with the second high temperature channel.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein the switching mechanism includes an air/smoke reversing valve arranged on the side of the low-temperature gas passage of each air passage and an air/smoke reversing valve arranged on the low-heat The coal/smoke reversing valve on the side of the low-temperature gas passage of the value gas passage, the air/smoke reversing valve is connected to the low-temperature gas passage of the air passage, the air supply pipeline and the air-smoke pipeline, and the coal/smoke reversing valve The valve is connected to the low-temperature gas channel, the gas supply pipeline and the soot pipeline of the low calorific value gas channel.

The regenerative soaking furnace burning low-calorific-value gas according to claim 1, wherein the low-temperature heating system includes low-temperature heating burners arranged on both side walls of the furnace wall of the soaking furnace, so that The low-temperature heating burner is connected with the high calorific value gas pipeline and the air supply pipeline.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein, the furnace cover of the soaking furnace is an arched furnace cover, and the furnace cover adopts an integral pouring structure, and the hanging bricks inside are double-clamped hanging structure.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein the double-clamped tube hanging structure includes a hanging tube and two hanging clips, and the two hanging clips are in a cross shape to hang the bricks It is hoisted on the hanging pipe, and then poured as a whole to form the furnace cover.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein the furnace mouth of the soaking furnace is composed of a plurality of furnace bricks, and the upper end of the furnace body is provided with a channel steel as a locking structure , The bottom of the furnace mouth brick is provided with an embedding groove matched with the channel steel.

In the regenerative soaking furnace burning low-calorific-value gas as described above, a groove corresponding to the sand sealing structure is provided on the upper part of the furnace mouth brick, and bendable lifting lugs are provided in the groove.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein the low-temperature heating system includes low-temperature heating burners arranged on both side walls of the furnace wall of the soaking furnace, and the low-temperature heating burners It is connected with the high calorific value gas pipeline and the air supply pipeline; the furnace cover of the soaking furnace is an arched furnace cover, and the furnace cover adopts an integral pouring structure, and the hanging bricks inside adopt a double-clamp hanging structure; The double-clamp tube type hanging structure includes a hanging tube and two hanging clips, and the two hanging clips are in a cross shape to hang the hanging bricks on the hanging tubes, and then perform integral casting to form a furnace cover; The furnace mouth of the soaking furnace is composed of a plurality of furnace mouth bricks, the bottom of the furnace mouth brick is provided with an embedded groove matching the channel steel; the upper part of the furnace mouth brick is corresponding to the groove of the sand seal structure There are bendable lifting lugs inside.

The regenerative soaking furnace for burning low calorific value gas as described above, wherein the first end of the regenerator box is dispersedly provided with a plurality of low-temperature gas passages, and the low-temperature gas passages are located at the outlet of the regenerator box There is also a structure that can disperse and rectify the airflow.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein, the high-temperature gas channel and the inner wall of the top of the heat storage box are provided with an insulating lining as a heat preservation structure; the side walls of the heat storage box are cast The overall pouring structure of the material; the heat storage box adopts the fiber module ceiling structure, and the top uses high temperature resistant refractory fiber as the working layer and the heat insulation layer.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein each air channel and/or the high-temperature gas channel of the low-calorific gas channel is connected to the combustion furnace body in a bend, and the joint has a flexible sealing structure.

The regenerative soaking furnace for burning low-calorific gas as described above, wherein the low-calorific gas nozzles used in conjunction with the furnace body are located on the same side and the corresponding air nozzles are arranged up and down and meet obliquely.

The regenerative soaking furnace for burning low-calorific-value gas as described above, wherein the air nozzle and the low-calorific-value gas nozzle have a large intersection angle of 30-90°, which is conducive to the high-temperature combustion of air and gas under large gas flow conditions. Under the rapid and thorough mixing, and the uniformity of the temperature distribution of the temperature field in the furnace.

The regenerative soaking furnace for burning low-calorific-value gas as described above, wherein the width of the air nozzle is similar to or equal to that of the low-calorific-value gas nozzle.

The regenerative soaking furnace for burning low-calorific-value gas as described above, wherein the low-calorific-value gas nozzles and air nozzles arranged up and down are provided with convex rectification structures to form a rectification-type nozzle combination structure, so that the air flow Combustion mixes better and has less resistance to flow.

Features and advantages of the present invention are as follows:

① The present invention adopts high-temperature and low-temperature dual heating systems.

The ignition temperature of blast furnace gas is relatively high (>750°C), while the heating of wide and thick plates or steel ingots requires heating and heat preservation in various temperature ranges. In order to meet the needs of low-temperature heating, in addition to the regenerative high-temperature heating system, the present invention also sets up a set of low-temperature heating system, which shares air supply and smoke exhaust pipelines with the regenerative combustion high-temperature heating system, which can realize different Furnace shutdown switch.

② The present invention adopts the regenerative combustion system of the high-temperature regenerative combustion technology, so that the gas with low calorific value (blast furnace gas) can be used as fuel.

The heating temperature of the soaking furnace is relatively high. When pure blast furnace gas is used for heating the soaking furnace, if it is not preheated, it cannot be directly used for heating the steel ingot at 1320°C. The invention adopts the modern thermal storage combustion method to realize the full recovery technology of waste heat which directly uses the blast furnace gas in the heating process.

The high-temperature heating system adopts an independent air and gas heat storage box with high-temperature external channels, which can preheat air and gas to above 1000°C. Since the air and gas heat storage boxes are independent structures, no air and gas will occur The risk of explosion due to mixing ensures the safety of production.

Due to the high temperature of the soaking furnace and the high dust content of the furnace gas, the regenerator adopts a spherical regenerator, which is not only resistant to high temperature, but also easy to replace the regenerator.

③A long-life arched furnace cover with double-clamp type suspension is adopted.

Most of the existing soaking furnaces adopt the roof structure with prefabricated bricks or castables suspended from the flat top, and the unreasonable force causes the service life to be short. In order to improve the service life of the furnace cover, the present invention changes the flat-top furnace cover into an arched furnace cover, and the force of such a structure is more reasonable. The suspension structure is made more compact, and the adaptability to angle changes is better.

The furnace cover adopts a multi-layer composite thermal insulation structure, which is lighter in weight and better in thermal insulation.

④Adopt replaceable furnace mouth brick and notch locking structure to enhance maintainability.

The furnace mouth brick of the soaking furnace is a vulnerable part. In order to reduce the maintenance cost, the present invention adopts a replaceable prefabricated brick structure. Prefabricated bricks can not only be replaced, but also have uniform specifications and are interchangeable, which facilitates partial maintenance and replacement.

The bottom of the prefabricated brick has an embedded groove, combined with the channel steel locking structure, which can effectively prevent the inclination of the furnace wall caused by the sliding of the sealing sand, and can reliably position the furnace mouth brick.

Description of drawings

Fig. 1 is a schematic diagram of a combustion system of a specific embodiment of the regenerative soaking furnace of the present invention.

Fig. 2 is a schematic cross-sectional view of a specific embodiment of the regenerative soaking furnace of the present invention (not all are shown, and the gas channel and the air channel outside the furnace body are respectively shown on both sides).

FIG. 2A is an enlarged schematic diagram of a partial structure of FIG. 2 .

Fig. 3 is a schematic top view of the regenerative soaking furnace in Fig. 2 .

FIG. 3A is an enlarged schematic diagram of a partial structure of FIG. 3 .

Fig. 4 is a schematic diagram of a partial structure of a heat storage box adopted in a specific embodiment of the present invention, mainly showing a schematic diagram of a combined lining structure of a castable material and a fiber module.

Fig. 5 is a schematic diagram of a model of a rectification spout with a large angle of intersection and gas up and down converging and rectifying nozzles adopted in a specific embodiment of the present invention.

Fig. 6 is a schematic structural view of the arched furnace cover used in a specific embodiment of the present invention.

Fig. 6A is a schematic structural diagram of the double-clamp tube suspension used in the arched furnace cover in Fig. 6, which also shows the metal skeleton on the upper part of the furnace cover for hanging the hanging tubes.

Fig. 6B is a structural schematic view in another direction of the double-clamp-type hanging used in the arched furnace cover in Fig. 6 .

Fig. 7 is a schematic structural diagram of replaceable furnace mouth bricks used in a specific embodiment of the present invention.

Fig. 7A is a schematic diagram of the furnace mouth brick in Fig. 7 being applied to the furnace mouth of a regenerative soaking furnace.

Explanation of reference numbers:

10, 10’, 30’, 30’, channel structure 11, 11’, high temperature gas channel

12, 12’, heat storage tank 13, 13’, low temperature gas channel

103, 103’, 303’, 303’, nozzle 105, 105’, nozzle section

107, 107', connection section 108, raised structure

13. Low temperature gas channel 101. Furnace body 102. Furnace cover

120. Heat storage box 121. Heat storage body 122. Metal frame

123. Shell 124. Insulation lining 125. Fiber module

126. Heat-resistant steel components 127. Side walls 131. Furnace mouth bricks

132. Double pinch type hanging structure 133. Hanging tube 134. Hanging steel wire

135. Hanging bricks 136. Inserting groove 137. Hanging lugs

138. Channel steel 143. Metal furnace shell 144. Composite furnace lining

21. High temperature heating system 23. Low temperature heating system 200. Soaking furnace

211. Blast furnace gas channel 212. The first coal/smoke reversing valve 213. The second coal/smoke reversing valve

215. Air channel 216. First air/smoke reversing valve 217. Second air/smoke reversing valve

222. Blast furnace gas pipeline 224. Natural gas pipeline 225. Air supply pipeline

226. Combustion fan 227. Empty smoke pipeline 228. Soot pipeline

231. Low-temperature heating burner 234. High calorific value gas pipeline 271. Air-smoke induced draft fan

273. Empty smoke chimney 281. Soot induced draft fan 283. Soot chimney

Detailed ways

In order to be able to understand the technical means of the present invention more clearly, it can be implemented according to the contents of the description, and in order to make the above-mentioned and other purposes, features and advantages of the present invention more obvious and understandable, the following preferred embodiments are specially cited and combined with Accompanying drawing, detailed description is as follows.

As shown in Figure 1, it is a schematic diagram of the combustion system of a regenerative soaking furnace burning blast furnace gas according to the present invention. The furnace 200 is equipped with a regenerative high-temperature heating system 21 using blast furnace gas for heating and a low-temperature heating system 23 using high-calorific-value gas for heating, and the low-temperature heating system 23 and the high-temperature heating system 21 share the air supply pipeline 225 and the smoke exhaust pipeline (empty smoke pipeline 227).

In this embodiment, the high-temperature heating system 21 preferably includes first and second high-temperature channel combinations and switching mechanisms arranged in pairs on both sides of the soaking furnace 200, and each high-temperature channel combination includes blast furnace gas channels 211 arranged on the same side It is connected with the air channel 215, the blast furnace gas channel 211 is connected with the blast furnace gas pipeline 222 and the soot pipeline 228, and the air channel 215 is connected with the air supply pipeline 225 and the air smoke pipeline 227; the switching mechanism makes the first and second The combination of high temperature passages can be switched to alternately act as a combination of combustion passages or a combination of smoke exhaust passages. In this embodiment, in order to better ensure smoke exhaust safety, the smoke exhaust pipeline is divided into an empty smoke pipeline 227 and a soot pipeline 228 , which communicate with the air channel 215 and the blast furnace gas channel 211 respectively.

The combustion system of the present invention is equipped with corresponding valves on each pipeline, wherein the switching mechanism of the high temperature heating system 21 includes an air/smoke reversing valve arranged on the pipeline on one side of each air channel and a valve on one side of each blast furnace gas channel. Each air/smoke reversing valve is connected to the air channel, air supply pipeline and air-smoke pipeline, and each coal/smoke reversing valve is connected to the blast furnace gas channel, gas supply pipeline and soot pipeline. Specifically in FIG. 1 , the switching mechanism includes a first coal/smoke reversing valve 212 , a first air/smoke reversing valve 216 , a second coal/smoke reversing valve 213 , and a second air/smoke reversing valve 217 . Preferably, each reversing valve is a two-position three-way valve, including a closed position, and the action sequence of each reversing valve is, for example: close->open a valve plate of the three-way valve->exhaust smoke->close-> Open the other valve plate of the three-way valve -> air intake, wherein the first external interface of the first coal/smoke reversing valve 212 is connected to the blast furnace gas passage through a pipeline, and its second external interface and third external interface The interface is respectively connected to the blast furnace gas pipeline and the soot pipeline, and the switching of blast furnace gas/soot discharge function is realized through the reversing valve; the first external interface of the first air/smoke reversing valve 216 is connected to the The air passage, its second external interface and third external interface are respectively connected to the air supply pipeline 225 and the air-smoke pipeline 227, through which the reversing valve realizes the switching of the function of introducing air/expelling air and smoke. The setting methods of the second coal/smoke reversing valve 213 and the second air/smoke reversing valve 217 on the other side are similar and will not be repeated here.

As shown in Figure 1, the low-temperature heating system 23 includes low-temperature heating burners 231 arranged on both sides of the furnace wall of the soaking furnace 200, and the low-temperature heating burners 231 are connected to a high calorific value gas pipeline 234 and an air supply pipeline 225, In this embodiment, natural gas is used as the fuel of the low-temperature heating system, that is, the high calorific value gas is natural gas, but it is not limited thereto. The natural gas combustion system used for low-temperature heating in this embodiment is equipped with independent natural gas pipelines and air pipelines, and the natural gas burner is used to realize combustion and heat supply. The air pipeline of the natural gas burner is a branch pipeline of the high-temperature heating system. That is, it is taken from the air main of the high temperature heating system. When the low-temperature heating system is in use, the blast furnace gas part (including pipelines and channels) of the regenerative combustion system is closed, but the reversing switching of the regenerative combustion and the air supply are still in working state, so it can realize low-temperature heating. Combustion heat supply and waste heat recovery function of natural gas combustion system.

The preferred embodiment of the present invention adopts a dual heating system of high temperature and low temperature heating, which can fully meet the needs of low temperature heating. The low-temperature heating system and the regenerative combustion system share the air supply and smoke exhaust pipelines, which can realize non-stop furnace switching.

The working principle of this embodiment is briefly described below:

For the high-temperature heating system, the normal-temperature air blown out by the combustion-supporting blower 226 passes through the air supply duct 225 and passes through the first air/smoke reversing valve 216 on one side of the furnace body (as shown in FIG. 1 on the left side) and enters the side of the furnace body The air channel (the high-temperature channel combination on the other side has been switched to the smoke exhaust state) is then heated in the regenerator of the air channel, so that the normal temperature air is heated to close to the furnace temperature in a very short time, at this time Since the first coal/smoke reversing valve 212 on the blast furnace gas pipeline 222 on this side is in the air intake position, the blast furnace gas enters the blast furnace gas channel on this side through the reversing valve, and is absorbed in the heat storage tank of the channel. Heating to close to the furnace temperature, therefore, after the heated high-temperature hot air enters the soaking furnace body, it is mixed with the blast furnace gas for combustion, and at the same time, part of the hot flue gas after combustion in the furnace body is in the soot induced draft fan 281, the air smoke induced draft fan Under the action of 271, it is discharged to the outside of the soot chimney 283 and the empty smoke chimney 273 through the combination of high-temperature channels in the smoke exhaust state on the other side of the furnace body (the right side shown in Figure 1). The heat storage bodies in the channels and air channels store heat.

After burning for a predetermined time (such as 120-150s), the first coal/smoke reversing valve 212 and the first air/smoke reversing valve 216 can be closed, and then the high temperature channel combination on this side can be switched to the smoke exhausting state by using the switching mechanism , and switch the combination of high-temperature channels on the other side to the intake state, so as to realize the conversion of functions, and the input gas is rapidly heated by the heat storage body that has completed heat storage, so that the temperature is raised to a level close to the furnace temperature, so that It is beneficial to realize high-temperature heating and combustion, so that a cycle of high-temperature regenerative combustion process is completed.

When low-temperature heating is required, the blast furnace gas pipeline and soot pipeline for regenerative combustion should be closed, the natural gas pipeline and air supply pipeline should be opened, and the natural gas burner on the side wall of the furnace body should be used to realize combustion and heat supply. At this time, The air supply pipelines and related reversing valves on both sides work normally, that is, the air channel on one side (as shown on the left in Figure 1) is switched to the air inlet position by the reversing valve, and the air channel on the other side (as shown in Figure 1 The air channel on the right (shown on the right) is switched to the smoke exhaust position by the corresponding reversing valve to realize the functions of smoke exhaust and heat storage; after working for a period of time, switch the reversing valve corresponding to the air channel on one side to the smoke exhaust position position, and switch the reversing valve corresponding to the air channel on the other side to the air intake position. Since the heat storage box of this air channel has exhausted and stored heat before, the normal temperature air entering at this time can be stored at an extremely high temperature. It is heated to close to the furnace temperature in a short period of time, and participates in the combustion as part of the air required for the combustion of the natural gas burner, which is beneficial to the recovery of waste heat from the flue gas.

After a period of heating or soaking with the low-temperature heating system, if further high-temperature heating of steel ingots or wide and thick plates in the furnace is required, the natural gas pipeline only needs to be closed, and the high-temperature heating system (especially blast furnace gas Pipeline) can be realized by appropriate switching, since its implementation method is consistent with the foregoing content, it will not be repeated here.

In this embodiment, the low-temperature heating system 23 can be used to realize heating or soaking at a temperature below 800° C., and the high-temperature heating system can be used to realize heating or soaking at a temperature between 800° C. and 1320° C., thereby realizing dual heating functions of high and low temperatures.

As shown in Figure 1, in this embodiment, manual cut-off valves (with "M" symbol), temperature detection elements (with "P" symbol) and automatic flow adjustment are also provided on each blast furnace gas pipeline and each air pipeline as required. Valve (with "V" symbol), etc., to facilitate the control and maintenance of the overall combustion system. Those skilled in the art can accurately understand the setting of the relevant valves based on the foregoing content and the accompanying drawings, so details will not be repeated here.

As shown in Figure 1, this embodiment burns gas with low calorific value (such as blast furnace gas), adopts a regenerative combustion system with high-temperature regenerative combustion technology, is equipped with an independent empty gas regenerator, and cooperates with the use of a reversing valve to complete High temperature regenerative combustion function.

In addition, in addition to natural gas, the fuel used for low-temperature heating can also use other gaseous fuels with high calorific value, such as coke oven gas, mixed gas, city gas, etc., and the fuel used in the regenerative combustion system can also use other low-calorific Value gas fuel, such as producer gas, etc.

As shown in FIG. 2 , it is a structural schematic diagram of a specific embodiment of the regenerative soaking furnace of the present invention. In this embodiment, the side wall of the soaking furnace body is provided with a low-temperature heating burner 14. The specific setting method can refer to other embodiments, and will not be repeated here. The main feature of this embodiment is that its high-temperature heating system Each channel structure is equipped with a heat storage box independent of the furnace body.

Specifically, in this embodiment of the present invention, the soaking furnace includes a furnace body 101 and a furnace cover 102. The furnace body of the soaking furnace includes a metal furnace shell 143 and a composite lining 144 inside, and its high-temperature heating system adopts Independent air and gas heat storage tank with high temperature external channel and spherical heat storage body. 2A to 3A, the high-temperature heating system of the soaking furnace includes first and second channel structures 10, 10' arranged in pairs on one side of the soaking furnace and third channel structures 10, 10' arranged in pairs on the opposite side. , the fourth channel structure 30, 30 ', the basic structure of the first and second channel structures and the third and fourth channel structures are the same, all including high temperature gas channel 11, heat storage box 12 and low temperature gas channel 13, each heat storage The box 12 includes a heat storage box 120 and a heat storage body 121 arranged inside it. One end of the heat storage box 120 is provided with a low-temperature gas passage 13 connected to a pipeline, and the other end is provided with a high-temperature gas channel connected to the furnace body 101. Passage 11; the side wall on one side of the furnace body 101 is provided with a first nozzle 103 corresponding to the first passage structure 10 for connecting with the first passage structure, and corresponding to the second passage structure 10' is provided with a nozzle 103 for connecting with the second passage structure. The connected second nozzle 103', similarly, the third nozzle 303 for connecting with the third channel structure 30 and the third nozzle 303 for connecting with the fourth channel structure are provided on the side wall on the other side corresponding to the third and fourth channel structures The channel structure 30' connects with the fourth nozzle 303'.

In this embodiment, blast furnace gas is used as the fuel of the high-temperature heating system. Therefore, the above-mentioned first and second passage structures actually correspond to blast furnace gas passages and air passages, and the first nozzle 103 and the third nozzle 303 are blast furnace gas nozzles. The second nozzle 103' and the fourth nozzle 303' are air nozzles. The specific composition and characteristics of each channel structure will be described in detail below.

As shown in Fig. 3 and Fig. 3A, in this embodiment, each high-temperature gas channel 11 is bent and connected with the furnace body 101. As shown in the figure, the high-temperature gas channel 11 is connected after two bends in the extending direction. To the furnace body 101, this can effectively absorb the structural stress and strain caused by the temperature expansion of the high-temperature channel at high temperature; in addition, please refer to Figure 2A, and perform flexible sealing treatment on the joint A of the two to ensure the sealing Effect. As for the specific structure and process of the flexible sealing process, those skilled in the art can fully implement it by using the existing technology, so it will not be repeated here.

Optionally, please refer to FIG. 2 and FIG. 2A , the first end of the blast furnace gas heat storage tank 12 is dispersedly provided with a plurality of low-temperature gas channels 13 .

Please refer to FIG. 4 , which is a partial structural diagram of the heat storage box used in a specific embodiment of the present invention, mainly showing the combined inner lining structure of castable and fiber modules. The heat storage box 120 includes a metal frame 122 , an outer shell 123 and an inner heat insulating liner 124 . Please refer to FIG. 4 , the high-temperature gas channel 11 and the heat storage box 120 are made and reserved together, and the inner wall of the high-temperature gas channel 11 and the top inner wall of the heat storage box 120 are preferably equipped with thermal insulation linings as heat preservation structures.

As shown in Figure 4, the side wall 127 of the heat storage box 120 is preferably an integral casting structure of castables, and further, the side walls can be made of light and high-strength castables with high strength and low thermal conductivity (such as lightweight mullite Stone castables, etc.) pouring, and the heat-resistant steel anchor hook 129 can be used as the anchor. Preferably, the heat storage box 120 adopts a fiber module ceiling structure, specifically, the top uses light weight, high temperature-resistant refractory fiber as the refractory working layer and heat insulation layer in contact with high-temperature gas, preferably a temperature-resistant 1350 The special refractory fiber above ℃ is suspended on the top metal skeleton 122 with heat-resistant steel anchors 129, and the fiber modules 125 are interspersed and fixed with heat-resistant steel members 126. Of course, the top of the heat storage box 120 can also be made of the same material and structure as the side walls, such as integral casting or sequential casting, which will not be repeated here.

Based on the passage structure with the above-mentioned compositional characteristics, please refer to Fig. 3A and Fig. 5, in a specific embodiment of the present invention, the high-temperature gas passages 11, 11' on the same side of the furnace body 101 as the blast furnace gas passage and air passage The connected first nozzle 103 and the second nozzle 103' form a nozzle combination structure in which air and gas meet up and down, so as to facilitate rapid and sufficient mixing of high-temperature combustion under large gas flow conditions.

In a specific embodiment of the present invention, gas nozzles and air nozzles corresponding to a combination of high-temperature passages are arranged up and down and obliquely intersect to form a nozzle combination structure. Taking the first high-temperature channel combination as an example, the corresponding first (gas) nozzle 103 and second (air) nozzle 103' are arranged up and down and obliquely converging to form a nozzle combination structure.

Combined with the combination of the aforementioned channel structure and the furnace body, since each high-temperature gas channel is connected to the furnace body 101 in a bend, the furnace body 101 has inclined nozzle sections 105, 105' near the second nozzle. The spout segments 105, 105' intersect obliquely to form a combined spout structure. Preferably, in order to facilitate the smooth connection between the furnace body and each channel structure, in this embodiment, between the two nozzle sections 105, 105' and the two high-temperature gas channels 11, 11', the furnace body is also provided with straight The connecting sections 107, 107', the two connecting sections 107, 107' are parallel to each other and vertically arranged in a vertical relationship.

In a specific embodiment of the present invention, the centerlines of the two nozzle sections 105, 105' preferably have a large angle of intersection between 30° and 90°, for example, a large angle of intersection of about 45° can be used, which is beneficial to air, The high-temperature combustion of gas can be quickly and fully mixed under the condition of large gas flow rate, and can improve the uniformity of temperature distribution in the temperature field in the furnace.

In order to further strengthen the high-temperature combustion of air and gas under the condition of large gas flow rate, the rapid and sufficient mixing and improve the uniformity of temperature distribution in the furnace temperature field, the width of the second nozzle 103' and the first nozzle 103 are preferably kept close to or Equal, but there is no specific requirement on the height, which can be determined according to the needs.

In order to make the combustion mixing of the air flow better and the flow resistance smaller, in the present invention, the combined nozzle structure is preferably a rectified nozzle combined structure, that is, the first (gas) nozzle 103, the second (air) nozzle 103 arranged up and down A rectification structure is provided between the nozzles 103' to form a rectification nozzle structure. The rectification structure is preferably a structure with a smooth convex surface, such as an arc-shaped convex surface, preferably a semi-cylindrical convex structure 108 as shown in FIG. 5 , of course , it can also be a convex surface that has been smoothed by polygons, such as a smooth transition convex surface formed by trapezoidal, triangular, etc. Quality mixed.

As shown in the figure, the realization process of high-temperature regenerative combustion is through the switching function of the reversing valve, so that the air heat storage box and the gas heat storage box on one side are in the state of air supply and gas supply, and through the nozzle in the furnace , The fuel is fed into the furnace to realize combustion and heat supply. At the same time, the air heat storage box and the gas heat storage box on the other side suck the waste gas generated by combustion through the nozzle and high-temperature passage in the furnace, so that the waste gas can store heat on the heat storage body in the heat storage box, and will realize The exhaust gas from heat storage and heat exchange passes through the air smoke and soot pipes at extremely low temperature (150°C), and is discharged into the atmosphere through the induced draft fan and the chimney, thus realizing the combustion and heat supply on one side. After a certain period of time (120-150s), through the reversing function of the reversing valve, the combustion supply state on one side is switched to the exhaust gas discharge state, and the exhaust gas discharge state on the other side is switched to the combustion supply state. , the realization method is similar to that described above, so that a cycle of regenerative combustion process is completed.

It can be known from the above that this embodiment adopts a single-body (independent from the furnace) heat storage tank to obtain a heat storage combustion device with a large cross-section and a large gas exchange capacity, so that the internal channel size of the cross-sectional area can be greater than 1m ² , which can It is more than 1.5m ² , and reaches 2.88m ² in an application embodiment of the present invention, and the gas exchange rate can reach 12000Nm ³ /h, which cannot be realized by the existing regenerative combustion equipment.

As shown in FIG. 6 , it is a structural schematic diagram of the arched furnace cover adopted in a specific embodiment of the present invention. In this embodiment, in order to improve the service life of the furnace cover, this embodiment changes the flat-top furnace cover structure of the existing soaking furnace into an arched furnace cover structure, and the furnace cover adopts an integral casting structure, so that it is stressed more reasonable.

On the other hand, as shown in FIG. 6A , in this embodiment, the hanging method of the hanging brick 135 is changed to a double-clamp type hanging structure. Each double-clamp hanging structure 132 includes a hanging tube 133 and two hanging bricks The two hanging clips at the end, in a specific embodiment, the two hanging clips are the hanging parts on both sides of the upper part of the hanging brick by the hanging steel wire 134 in a cross shape, and the hooks at the two ends of the hanging steel wire 134 are crossed and fixed. Respectively hook and fix on the positions of the hanging tubes 133 corresponding to the two ends of the hanging bricks to form a double clamp type hanging, so that the hanging bricks 135 are hung on the hanging tubes 133 to make the hanging structure more compact. Better adaptability to angle changes.

The hanging brick 135 is hoisted on the hanging pipe 133 by means of double-clamp-type hanging, and then cast as a whole to form the furnace cover 102 . The insulation structure of the furnace cover is preferably in the form of multi-layer composite, so as to make the weight lighter and the insulation better.

As shown in Fig. 7 and Fig. 7A, it is a schematic diagram of the replaceable furnace mouth brick 131 and the locking structure adopted in a specific embodiment of the regenerative soaking furnace of the present invention. Since the furnace mouth brick of the soaking furnace is a vulnerable part, in order to reduce the maintenance cost, this embodiment adopts a replaceable prefabricated brick structure, that is, the furnace mouth of the soaking furnace is composed of a plurality of furnace mouth bricks 131, so that Prefabricated bricks can not only be replaced, but also have uniform specifications and are interchangeable, which facilitates partial maintenance and replacement.

Further, a channel steel locking structure can be set at the furnace mouth of the furnace body 101, that is, a channel steel 138 is set at the upper end of the furnace body 101 as a locking structure, and the bottom of the furnace mouth brick 131 is preferably provided with a channel steel 138 corresponding to the channel steel 138. Cooperating embedded groove 136, channel steel 138 is arranged on the upper end of the furnace body, one end of which is welded and fixed on the furnace body shell 143, and the other end is combined with the embedded groove 136 at the bottom of the furnace mouth brick 131, thereby effectively preventing the sealing sand from falling. The furnace wall is inwardly inclined, and the furnace mouth brick can be positioned reliably.

Preferably, a bendable lug 137 is provided in the groove corresponding to the sand sealing structure on the upper part of the furnace brick 131, and the lifting lug 137 is made to stand upright when the furnace brick 131 is installed and replaced, so as to provide better It is hoisted and fixed; after the installation is completed, it can be bent horizontally without affecting the sand sealing effect.

In this embodiment, a reasonable structural size and a fixed locking method can be adopted according to actual needs, so as to facilitate the replacement and maintenance of furnace mouth bricks, thereby reducing maintenance costs and improving economic benefits.

To sum up, the present invention proposes a soaking furnace that uses low calorific value gas (such as blast furnace gas) and adopts modern regenerative reversing high-temperature combustion technology. The soaking furnace does not need to reserve an additional smoke exhaust channel (conventional flue), and all the waste heat of the flue gas generated by combustion can be recovered, which has extremely high heating efficiency.

Considering that blast furnace gas usually cannot be combusted at low temperature (<750°C), in order to meet the requirements of the low-temperature heating process of the soaking furnace, the combustion system is also equipped with a natural gas combustion system suitable for low-temperature heating to meet the needs of low-temperature heating . Therefore, the combustion system is a high and low temperature dual heating system with high and low temperature heating functions. In addition, in order to ensure the combustion efficiency of blast furnace gas, the present invention adopts the high-temperature regenerative combustion technology of burning low calorific value gas (blast furnace gas). The air and gas heat storage box in the furnace body.

In order to improve the service performance and service life of the soaking furnace, the preferred embodiment of the present invention also improves the furnace cover and brick structure of the furnace mouth of the soaking furnace, and adopts a long-life arched furnace with double-clamp tube suspension Cover and notch locking structure, replaceable furnace brick, so that the structure of the soaking furnace is more reasonable, and the maintenance cost can be greatly reduced.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any skilled person who is familiar with the profession can use the technical content disclosed above to make some changes or Modified as an equivalent embodiment of an equivalent change, but any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belong to the technical solution of the present invention within range.

Claims (14)

1. the regenerative soaking pits of a lower heat of combustion coal gas, described soaking pit comprises body of heater and bell, it is characterized in that, described soaking pit is provided with and utilizes the low-temperature heating system that the high heating value combustion gas heats and the heat-accumulating type high-temperature heating system of utilizing low-heat value gas to heat, and described low-temperature heating system and heat-accumulating type high-temperature heating system share air feed and smoke-exhaust pipeline; Wherein said heat system comprise that described soaking pit both sides arrange in pairs first, the combination of the second high temperature channel and switching mechanism, described first, the combination of the second high temperature channel includes the air passageways structure that homonymy arranges, the low calorific value coal gas channel structure, described air passageways structure and air-supply pipeline, smoke-exhaust pipeline links to each other, described low calorific value coal gas channel structure and low calorific value coal air pipe, smoke-exhaust pipeline links to each other, described air passageways structure, the low calorific value coal gas channel structure includes high temperature gas passage, the cryogenic gas passage reaches the heat storage tank in the outside relatively independent setting of this soaking pit body of heater, described heat storage tank comprises accumulation of heat casing and the inner heat storage that arranges thereof, one end of described accumulation of heat casing is provided with the described cryogenic gas passage that links to each other with pipeline, and its other end is provided with the described high temperature gas passage that joins with body of heater; The sidewall of described body of heater one side is provided with respectively the corresponding air jet that joins of air, low calorific value coal gas channel structure and the low-heat value gas spout with the combination of the first high temperature channel, the sidewall of its opposite side is provided with respectively the corresponding air jet that joins of air, low calorific value coal gas channel structure and the low-heat value gas spout with the combination of the second high temperature channel, described switching mechanism so that described first, second high temperature channel combined and alternatively as combustion channels combination or discharge flue combination; Described low-temperature heating system is included in the low-temperature heat burner that arranges on the furnace wall two side of described soaking pit, and described low-temperature heat burner links to each other with high heating value gas pipeline and air-supply pipeline.

2. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 1, it is characterized in that, described switching mechanism comprises the sky of cryogenic gas passage one side of being located at described air passageways structure/cigarette reversing valve and is located at the coal of cryogenic gas passage one side of described low calorific value coal gas channel structure/cigarette reversing valve, described sky/cigarette reversing valve connects cryogenic gas passage, air-supply pipeline and the empty smoke pipe road of air passageways structure, and described coal/cigarette reversing valve connects cryogenic gas passage, supply air line and the coal smoke pipeline of low calorific value coal gas channel structure.

3. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 1 is characterized in that, the bell of described soaking pit is the arch bell, and this bell adopts integrated poured structure, and the hanger brick in it adopts double fastener tubular type hanging structure.

4. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 3, it is characterized in that described double fastener tubular type hanging structure comprises that hanging pipe and two hangs folder, described two hang cross-shaped hanger brick is hung at of folder hangs on the pipe, then carry out integrated pouredly, form bell.

5. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 1, it is characterized in that, the fire door of described soaking pit is to be combined by polylith fire door brick, and described body of heater upper end is provided with channel-section steel as the lock hanging structure, and the bottom of described fire door brick is provided with the caulking groove that matches with channel-section steel.

6. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 5 is characterized in that, described fire door brick top is provided with the groove corresponding with the sand seal structure, is provided with bent hanger in the described groove.

7. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 2, it is characterized in that, described low-temperature heating system is included in the low-temperature heat burner that arranges on the furnace wall two side of described soaking pit, and described low-temperature heat burner links to each other with high heating value gas pipeline and air-supply pipeline; The bell of described soaking pit is the arch bell, and this bell adopts integrated poured structure, and the hanger brick in it adopts double fastener tubular type hanging structure; Described double fastener tubular type hanging structure comprises to be hung pipe and two hangs folder, and described two hang cross-shaped hanger brick is hung at of folder hangs on the pipe, then carry out integrated poured, the formation bell; The fire door of described soaking pit is to be combined by polylith fire door brick, and the bottom of described fire door brick is provided with the caulking groove that matches with channel-section steel; Be provided with bent hanger in the groove corresponding with the sand seal structure of described fire door brick top.

8. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 1, it is characterized in that, the first end scattering device of described heat storage tank has a plurality of described cryogenic gas passages, and the outlet that described cryogenic gas passage is positioned at heat storage tank also is provided with the structure that air-flow is had the dispersion rectifying action.

9. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 8 is characterized in that, described high temperature gas passage and accumulation of heat casing top inner wall are provided with adiabatic liner as insulation construction; The sidewall of described accumulation of heat casing is the integrated poured structure of mould material; Described accumulation of heat casing adopts the fibre module ceiling structure, and its top adopts resistant to elevated temperatures refractory fibre as working lining and thermal insulation layer.

10. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 1 is characterized in that, the high temperature gas passage of each air passageways and/or low-heat value gas passage and burner block curve and join, and the connecting part has flexible sealing structure.

11. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 1 is characterized in that, it is setting up and down with corresponding air jet and tilt to cross that described body of heater is positioned at low-heat value gas spout that homonymy is used.

12. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 1, it is characterized in that, have 30～90 ° of large angles of cut between described air jet and low-heat value gas spout, the high-temp combustion that is conducive to air, coal gas under the atmospheric flow status fast, fully mix, and for the homogeneity of temperature field in furnace temperature distribution.

13. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 1 is characterized in that, described air jet is similar with the width of low-heat value gas spout or equate.

14. the regenerative soaking pits of lower heat of combustion coal gas as claimed in claim 11, it is characterized in that, be provided with the convex rectifier structure between described low-heat value gas spout setting up and down, air jet, form rectifier type spout unitized construction, resistance better, that flow is less so that the burning of air-flow mixes.

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