High-capacity sand-heating regeneration roaster

Abstract

A high-capacity sand heat regeneration roasting furnace, used for heat treatment of granules, comprises a furnace chamber, a working chamber, an isolation plate, a boiling head, and an air intake device; a boiling head connected to the air intake device is arranged on the bottom of the furnace chamber, and at least one isolation plate is arranged in the furnace chamber, the isolation plate divides the furnace chamber into several layers, each layer is a working chamber for accommodating granules, the isolation plate is provided with the boiling head, and the boiling head connects two adjacent spaces. The high-temperature gas in the roasting furnace is fully utilized in a layered manner, and under the same heat source condition, the heat energy is fully utilized, the yield of heat-treated particles is increased, and high efficiency and energy saving are achieved.

Description

Technical Field

[0001] The invention relates to the field of sand-heating regeneration roasting furnaces, in particular to the field of high-capacity sand-heating regeneration roasting furnaces. Background Art

[0002] Sand thermal regeneration is to roast the unusable part of the old sand by combustion or heat exchange, and obtain reusable regenerated sand after dust removal and screening. The combustion roasting furnace needs non-renewable natural gas to provide heat energy through combustion, and the heat exchange roasting furnace needs electricity to provide heat. However, whether it is heat exchange or combustion, the temperature in the furnace is relatively high, and the energy consumption is very large. How to use the generated heat more efficiently and realize the reuse of unit heat requires improvement of the existing roasting furnace. Summary of the invention

[0003] The invention overcomes the problem of insufficient heat utilization of existing natural gas roasting furnaces, provides a sand heat method regeneration roasting furnace, realizes the reuse of upper layer heat, reduces energy consumption, and improves production capacity.

[0004] A technical solution adopted by the present invention to solve its technical problem is:

[0005] A high-capacity sand heat regeneration roasting furnace, used for heat treatment of particulate matter, comprises a furnace chamber, a working chamber, an isolation plate, a boiling head, and an air intake device; a boiling head connected to the air intake device is arranged on the bottom surface of the furnace chamber, and at least one isolation plate is arranged in the furnace chamber, the isolation plate divides the furnace chamber into several layers, each layer is a working chamber for accommodating particulate matter, the boiling head is arranged on the isolation plate, and the boiling head connects two adjacent spaces.

[0006] The heat from the lower layer is transferred to the upper layer using an isolation plate with a boiling head. Because the organic matter in the lower layer is burned again, the temperature of the gas transferred upward is still high enough to heat the particulate matter. This not only increases the output but also makes full use of energy. Using the same energy, the output can at least double.

[0007] Preferably, the boiling head comprises a cavity, an air inlet and an air outlet, the air inlet and the air outlet are arranged on the cavity, and the upper surface of the cavity is a closed surface, the area of ​​the air inlet is 0.8 to 1.2 times the area of ​​the air outlet, the air inlet is connected to the air inlet device or the lower working chamber, the boiling heads are arranged in a matrix, the gas ejected from the boiling head air outlet is sprayed upward, or the gas ejected from the adjacent boiling head air outlet acts to generate an upward convective airflow.

[0008] The upper surface of the cavity is closed so that the boiling particles will not fall into the outlet or even block the outlet. The area of ​​the air inlet and outlet is controlled to control the pressure. At the same time, the boiling head is arranged so that the gas ejected from the boiling head outlet is sprayed upward or the gas ejected from the adjacent boiling head outlet generates an upward convection airflow after the action, thereby ensuring a certain height of boiling and improving the heat exchange effect.

[0009] Preferably, the wall thickness of the boiling head air outlet is greater than or equal to the maximum length between two points on the bottom surface of the accumulation body formed by the particles at the air outlet.

[0010] The movement direction of boiling particles is uncertain, and there is a high probability that they will enter the air outlet. The thickened wall design of the air outlet, that is, extending the passage of the air outlet, has a flow stabilizing effect on the one hand, and on the other hand, it makes the particles hit the wall in the passage and be blown out, or even if they accumulate at the air outlet when the blowing stops, they will not fall into the boiling head, which extends the life of the boiling head and prevents the particles on the upper layer from falling into the lower layer.

[0011] Preferably, it also includes a heating device arranged in each working cavity, the heating device includes an electric heating tube, the cavity extends along the bottom surface in the working cavity, the electric heating tube is arranged in the cavity, an air inlet is arranged at the upper part or one end of the cavity, and exhaust holes with downward openings are arranged at intervals at the bottom of the cavity, and the exhaust holes are at a set distance from the bottom surface of the working cavity.

[0012] When heating by electric heat, the electric heating tube is arranged in the cavity of the boiling head, and the cavity extends along the bottom surface to increase the length of the electric heating tube. At the same time, the exhaust hole is designed to open downward, so that the reaction of the bottom surface is utilized to make the air flow spray upward to boil the particles.

[0013] Preferably, it also includes a heating device, which is arranged in the lowest working chamber, or is arranged in the lowest working chamber and simultaneously arranged in at least one upper working chamber; the heating device includes a gas input pipe and an ignition device, and the working chamber is provided with an ignition device, the cavity extends upward, the gas input pipe is inserted into the cavity from the air inlet end pipe or is inserted outside the cavity, the gas input pipe at the end is connected to the cavity, and the air outlet is provided on the outermost side wall of the end.

[0014] When heating with gas, the best situation is that the gas and air or combustion-supporting gas are mixed in a certain space and then sprayed out from the gas outlet, ignited in the working chamber, so as to achieve complete combustion and make full use of the natural gas.

[0015] Preferably, it also includes a particle outlet, and a particle outlet is provided at one end of each of the working chambers; or it also includes a particle outlet and a particle outlet passage, and a particle outlet is provided at one end of at least one of the working chambers, and the working chamber with the particle outlet is located below the working chamber without the particle outlet, and the working chamber without the particle outlet is connected to the adjacent working chamber at the bottom through the particle outlet passage, and the particle outlet passage is located below the particle inlet.

[0016] Preferably, it also includes a particle inlet, and a particle inlet is set at one end of each of the working chambers; or it also includes a particle inlet and a particle inlet passage, and a particle inlet is set at one end of at least one of the working chambers, and the working chamber with the particle inlet is located above the working chamber without the particle inlet, and the working chamber without the particle inlet is connected to the upper adjacent working chamber through the particle inlet passage, and the particle inlet passage is located below the particle inlet.

[0017] Each working chamber can be an independent particle inlet and particle outlet, or one or more particle inlets and several particle inlet passages can be used to allow particles entering from above to be diverted at the particle passage, with one part in the upper working chamber and another part falling into the lower working chamber, or one or more particle outlets and several particle outlet passages can be used to allow upper particles to pass through the particle outlet passage. The appropriate particle inlet and outlet method can be selected according to the on-site conditions.

[0018] Preferably, it further includes a flow control device, and the particle inlet, the particle inlet passage, the particle outlet, and the particle outlet passage are all provided with a flow control device for controlling the amount of particles passing through.

[0019] A flow control device is set up to accurately know the flow rate, thereby controlling the amount of particles in each working chamber to complete the heat treatment work reasonably and efficiently.

[0020] Preferably, it also includes a cooling device and a dust removal device, wherein the cooling device is connected to the particle outlet, and the cooling device exchanges heat with the particles through the coolant or cold air in the spiral pipe, and the dust removal device is connected to the upper part of the furnace chamber and to the upper part of the cooling device.

[0021] The particles after high temperature treatment need to be cooled before they can be reused. The cooling pipe is used to exchange heat with the high temperature particles, so as to achieve the cooling effect. The gas can be heated at the cooling device before entering the furnace cavity, which can improve the energy utilization rate. A lot of dust will be generated during the heat treatment process, which is removed by the dust removal device set in the furnace cavity and the cooling device. The fineness of the final particles meets the requirements.

[0022] Preferably, the boiling heads on the isolation plates are arranged in a matrix, and the isolation plates are arranged obliquely, that is, the isolation plates are inclined from one end of the particle inlet to one end of the particle outlet.

[0023] The tilt setting is to make the thickness of the particles just entering thinner so that they can be heated more quickly, and the thickness of the subsequent layers will gradually thicken, so that the particles can be discharged more efficiently. A moderate tilt angle can improve work efficiency.

[0024] It can be seen from the above technical scheme that one beneficial effect brought about by one aspect of the present invention is to fully utilize the 600°C high-temperature gas in the roasting furnace in a layered manner, and under the same heat source conditions, fully utilize the thermal energy, increase the output of heat-treated particles, and achieve high efficiency and energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Attached Figure 1 It is a schematic diagram of the overall structure of a high-capacity sand-heating regeneration roasting furnace according to an embodiment disclosed in the present invention.

[0026] Attached Figure 2 The present invention discloses a gas-fired high-capacity sand-heating regeneration roasting furnace with a furnace chamber structure schematically.

[0027] Attached Figure 3 It is a structural schematic diagram of a furnace chamber portion of an electric high-capacity sand-heating regeneration roasting furnace disclosed in the present invention.

[0028] Attached Figure 4 It is a schematic structural diagram of the isolation plate portion of a high-capacity sand thermal regeneration roasting furnace according to the first embodiment disclosed in the present invention.

[0029] Attached Figure 5 It is a schematic structural diagram of the isolation plate portion of a high-capacity sand thermal regeneration roasting furnace according to the second embodiment disclosed in the present invention.

[0030] Attached Figure 6 It is a schematic structural diagram of the isolation plate portion of a high-capacity sand-heating regeneration roasting furnace according to the third embodiment disclosed in the present invention.

[0031] Attached Figure 7 The present invention discloses a schematic structural diagram of a boiling head portion of a gas-fired high-capacity sand-heating regeneration roasting furnace with a gas pipe input pipe.

[0032] In the figure: working chamber 20, isolation plate 30, boiling head 40, cavity 41, air inlet 42, air outlet 43, air intake device 50, heating device 60, electric heating tube 61, gas input pipe 62, particle outlet 70, particle outlet passage 80, particle inlet 90, particle inlet passage 100, cooling device 120, dust removal device 130. DETAILED DESCRIPTION

[0033] In conjunction with the accompanying drawings of the present invention, a technical solution of an embodiment of the invention is further elaborated in detail.

[0034] Thermal regeneration equipment can be used for heat treatment of sand with suitable particle size. The printed sand core is burned to remove the resin glue, and the remaining sand particles can be reused. The existing thermal regeneration equipment can only achieve single-layer sand burning. Because the flame burns directly in the boiling sand layer, it is traditionally believed that the sand layer is the place with the highest temperature. However, we found that the sand layer is not the hottest part of the furnace cavity. Specifically, when the surface temperature of the sand layer reaches 600°C, the organic matter on the upper layer of the furnace body is undergoing secondary combustion. This secondary combustion makes the upper air temperature reach above 700°C. This subverts the traditional concept. The heat generated by the secondary combustion can be used to heat treat the sand again or even multiple times. In this way, the problems of high energy consumption and heat energy waste in the sand regeneration process in the existing technology are solved, and the production efficiency is greatly improved.

[0035] The high-capacity sand heat regeneration roasting furnace provided by this scheme generally divides the traditional horizontal sand regeneration equipment into two or even multiple layers, and uses the original lower heating module for ignition heating to regenerate the lower sand while using the generated waste heat to regenerate the upper old sand. When it is designed into multiple layers, a partial heating device 60 can be added to the third layer, so as to use part of the lower heat and part of the new heat to complete the regeneration, and the generated waste heat is also sufficient to process the particles of the fourth layer. The air intake device 50 or the waste heat at the bottom blows the sand into the air through the outlet 43 of the boiling head 40 to form a sand suspension layer, thereby ensuring the adequacy of sand regeneration; the sand regeneration equipment is also provided with a dust removal device 130 and a remote monitoring system. The sand regeneration equipment realizes the equipment operation status such as start and stop through automatic operation and remote monitoring, thereby improving the utilization rate of the equipment and reducing the consumption in the non-working state.

[0036] Embodiment 1:

[0037] See attached Figure 1 As shown, a high-capacity sand heat regeneration roasting furnace is used for heat treatment of particulate matter, including a furnace chamber, a working chamber 20, an isolation plate 30, a boiling head 40, an air intake device 50, a heating device 60, a particle inlet 90, a particle outlet 70, and a flow control device.

[0038] The bottom surface of the furnace cavity is provided with a boiling head 40 connected to the air intake device 50 and the heating device 60, and at least one isolation plate 30 is provided in the furnace cavity. Figure 4 As shown, the isolation plate 30 divides the furnace cavity into several layers, each layer is a working chamber 20 for accommodating particulate matter, and the boiling head 40 is arranged on the isolation plate 30, and the boiling head 40 connects two adjacent spaces.

[0039] A particle inlet 90 is provided at one end of each of the working chambers 20, and a particle outlet 70 is provided at the other opposite end. Flow control devices are provided at the particle inlet 90 and the particle outlet 70 to control the amount of particles passing through. A cooling device 120 is communicated with the particle outlet 70, and the cooling device 120 performs heat exchange with the particles through the coolant or cold air in the spiral pipe. The dust removal device 130 is communicated with the upper part of the furnace chamber and is communicated with the upper part of the cooling device 120.

[0040] The boiling head 40 includes a cavity 41, an air inlet 42 and an air outlet 43. The cavity 41 is provided with the air inlet 42 and the air outlet 43, and the upper surface of the cavity 41 is a closed surface. The area of ​​the air inlet 42 is 0.8 to 1.2 times the area of ​​the air outlet 43. The air inlet 42 is connected to the air inlet device 50 or the lower working chamber 20. The wall thickness of the air outlet 43 of the boiling head 40 is greater than or equal to the maximum length between two points on the bottom surface of the accumulation body formed by the accumulation of the particles at the air outlet 43.

[0041] The boiling heads 40 are arranged in a matrix, and the gas ejected from the gas outlets 43 of the boiling heads 40 is ejected upward or the gas ejected from the gas outlets 43 of the adjacent boiling heads 40 reacts to generate an upward convection airflow. The arrangement of the boiling heads 40 is to ensure that the gas ejected from the gas outlets 43 can form an upward airflow instead of a turbulent flow.

[0042] The isolation plate 30 is tilted, that is, the isolation plate 30 is tilted from one end of the particle inlet 90 to one end of the particle outlet. When the isolation plate 30 is tilted, the air outlets 43 of all boiling heads 40 are preferably on the same horizontal plane, so that the airflows ejected from the air outlets 43 of adjacent boiling heads 40 collide with each other, and after interaction, an upward airflow is formed. If the boiling heads 40 are arranged randomly, then turbulence is formed between the adjacent air outlets 43, and there is no way to boil the particles, and it cannot work.

[0043] Specifically, an isolation plate 30 is provided in the middle of the furnace cavity of the roasting furnace, and the isolation plate 30 divides the furnace body of the roasting furnace into an upper space and a lower space. The roasting furnace with this structure can regenerate 5 to 6 tons of old sand, which is twice the previous regeneration amount.

[0044] High-temperature resistant electric butterfly valves are installed on the particle inlet 90 and the particle outlet 70 to control the amount of sand entering and exiting, ensuring that the entire boiling system is in a stable operating state. The middle dividing layer can be increased or decreased according to the actual production capacity requirements; the corresponding combustion plate at the bottom of the lower space can also be increased or decreased according to the roasting amount.

[0045] The split layer is welded to the inner wall of the furnace body and can be set horizontally or tilted downward from the sand inlet to the sand outlet to facilitate the flow of sand, that is, to conveniently flow the old sand from the sand inlet to the sand outlet, so as to realize the movement of the high-concentration sand from the sand inlet to the low-concentration sand at the sand outlet, and the tilt angle is 10 to 15 degrees. At the same time, an igniter is also provided on the side wall of the furnace body to realize the ignition of the bottom combustion plate. At the same time, a high-temperature electric butterfly valve can also be provided on the drop hole of the split layer to realize the control of the roasting amount of the old sand in the lower space; the electric butterfly valve on the sand inlet and the electric butterfly valve on the drop hole can also be linked to realize the effective control of the sand inlet amount in the furnace body to ensure the comprehensiveness of roasting regeneration.

[0046] Embodiment 2:

[0047] See attached Figure 2 As shown, the only difference from Example 1 is that the isolation plate 30 is arranged horizontally, the structure is easy to assemble, and there is no need to level the air outlets 43 of all boiling heads 40 on the isolation plate 30 as in Example 1, which is easier to manufacture.

[0048] At the same time, the entire furnace cavity is provided with a particle inlet 90 at one end of the uppermost working chamber 20, and a particle outlet 70 at one end of the lowermost working chamber 20. The intermediate working boxes are connected by a particle outlet passage 80 and a particle inlet passage 100. Figure 5 As shown, the particle outlet passage 80 and the particle inlet passage 100 are both arranged on the isolation plate 30, the working chamber 20 provided with the particle inlet port 90 is located above the working chamber 20 without the particle inlet port 90, and the working chamber 20 without the particle inlet port 90 is connected with the upper adjacent working chamber 20 through the particle inlet passage 100, and the particle inlet passage 100 is located below the particle inlet port 90, the working chamber 20 provided with the particle outlet port 70 is located below the working chamber 20 without the particle outlet port 70, and the working chamber 20 without the particle outlet port 70 is connected with the lower adjacent working chamber 20 through the particle outlet passage 80, and the particle outlet passage 80 is located below the particle inlet port 90. Wherein, the particle inlet passage 100 and the particle outlet passage 80 are both provided with flow control devices for controlling the amount of particles passing through, such as a high temperature resistant electric butterfly valve, to control the particle flow and flow rate. By reducing the passages, the internal work of the furnace chamber can be better controlled, heat dissipation can be reduced, and efficiency can be improved.

[0049] Embodiment 3:

[0050] See attached Figure 3As shown, on the basis of Example 1 or Example 2, the heating device 60 is an electric heating tube 61, that is, heating is performed by means of the electric heating tube 61. The electric heating tube 61 is arranged in the cavity 41 of the boiling head 40. The cavity 41 extends along the bottom surface in the working chamber 20, thereby increasing the contact area between the electric heating tube 61 and the particulate matter. An air inlet 42 is arranged at the upper part or one end or both ends of the cavity 41. The bottom of the cavity 41 is provided with exhaust holes with downward openings at intervals. The exhaust holes are at a set distance from the bottom surface of the working chamber 20. In the bottom working chamber 20, the air intake device 50 inputs gas into the boiling head 40, and passes through the electric heating tube 61, thereby bringing out hot air, so that the working chamber 20 reaches the working temperature, and the heat released by the secondary combustion of the organic matter in the working chamber 20 is introduced into the upper working chamber 20 for reuse. Refer to the attached Figure 6 As shown, a long device cavity 41 is provided on the isolation plate 30, and connecting pipes at both ends of the cavity 41 are connected to the lower working chamber 20, so that the hot air from the lower working chamber 20 is introduced into the cavity 41. Because it is a long cavity 41, the air outlet 43 of the boiling head 40 is set to open downward, and the gas is sprayed to the bottom and then reflected upward, thereby boiling the particles.

[0051] Embodiment 4:

[0052] On the basis of Example 1 or Example 2, refer to the attached Figure 7 As shown, the heating device 60 is a gas input pipe 62 and an ignition device. The ignition device is arranged in the working chamber 20. The chamber 41 extends upward. The gas input pipe 62 is inserted into the chamber 41 or outside the chamber 41 from the air inlet 42 end pipe. The gas input pipe 62 at the end is connected with the chamber 41, and the outermost side wall of the end is provided with the air outlet 43. The gas heating device 60 is arranged in the bottom working chamber 20, or in the bottom working chamber 20 and at least one upper working chamber 20 at the same time. Heating by natural gas combustion requires sufficient mixing of air and natural gas to improve combustion efficiency and ensure complete combustion, so that the set temperature can be reached as soon as possible.

Claims

1. A high-capacity sand-heating regeneration roasting furnace for heat treatment of particulate matter, characterized in that: It comprises a furnace cavity, a working cavity, an isolation plate, a boiling head, and an air intake device; a boiling head connected to the air intake device is arranged on the bottom surface of the furnace cavity, and at least one isolation plate is arranged in the furnace cavity, the isolation plate divides the furnace cavity into several layers, each layer is a working cavity for accommodating particles, the boiling head is arranged on the isolation plate, the boiling head connects two adjacent spaces, and the isolation plate is inclined from one end of the particle inlet to one end of the particle outlet; The boiling head comprises a cavity, an air inlet and an air outlet, the cavity is provided with the air inlet and the air outlet, and the upper surface of the cavity is a closed surface, the area of ​​the air inlet is 0.8 to 1.2 times the area of ​​the air outlet, and the air inlet is connected with the air inlet device or the lower working chamber; the boiling heads are arranged in a matrix, the gas ejected from the air outlet of the boiling head is ejected upward, or the gas ejected from the air outlet of the adjacent boiling head generates an upward convection airflow after the action, the air outlets are in the same plane, the air outlet is arranged on the outermost side wall of the end of the boiling head, and the wall thickness of the air outlet of the boiling head is greater than or equal to the maximum length between two points on the bottom surface of the accumulation body formed by the accumulation of the particles at the air outlet; It also includes a particle outlet, and each of the working chambers is provided with a particle outlet at one end; or it also includes a particle outlet and a particle outlet passage, and at least one of the working chambers is provided with a particle outlet at one end, and the working chamber provided with the particle outlet is located below the working chamber without the particle outlet, and the working chamber without the particle outlet is connected with the adjacent working chamber at the lower part through the particle outlet passage, and the particle outlet passage is located below the particle inlet; It also includes a particle inlet, and each of the working chambers is provided with a particle inlet at one end; or it also includes a particle inlet and a particle inlet passage, and at least one of the working chambers is provided with a particle inlet at one end, and the working chamber provided with the particle inlet is located above the working chamber without the particle inlet, and the working chamber without the particle inlet is connected with the upper adjacent working chamber through the particle inlet passage, and the particle inlet passage is located below the particle inlet; When the surface temperature of the sand layer reaches 600℃, the organic matter in the upper layer of the furnace body undergoes secondary combustion. This secondary combustion makes the upper air temperature reach above 700℃. The heat generated by the secondary combustion is used to heat treat the sand once or even multiple times.

2. The high-capacity sand-heating regeneration roasting furnace according to claim 1 is characterized in that: It also includes a heating device arranged in each working cavity, the heating device includes an electric heating tube, the cavity extends along the bottom surface in the working cavity, the electric heating tube is arranged in the cavity, an air inlet is arranged at the top or one end of the cavity, and exhaust holes with downward openings are arranged at intervals at the bottom of the cavity, and the exhaust holes are at a set distance from the bottom surface of the working cavity.

3. The high-capacity sand-heating regeneration roasting furnace according to claim 1 is characterized in that: It also includes a heating device, which is arranged in the lowest working chamber, or is arranged in the lowest working chamber and at least one upper working chamber at the same time; the heating device includes a gas input pipe and an ignition device, and the ignition device is arranged in the working chamber, the cavity extends upward, the gas input pipe is inserted into the cavity from the air inlet end pipe or is inserted outside the cavity, the gas input pipe at the end is connected to the cavity, and the air outlet is arranged on the outermost side wall of the end.

4. The high-capacity sand-heating regeneration roasting furnace according to claim 1 is characterized in that: It also includes a flow control device. The particle inlet, the particle inlet passage, the particle outlet, and the particle outlet passage are all provided with flow control devices for controlling the amount of particles passing through.

5. The high-capacity sand-heating regeneration roasting furnace according to claim 1 is characterized in that: It also includes a cooling device and a dust removal device. The cooling device is connected to the particle outlet. The cooling device exchanges heat with the particles through the coolant or cold air in the spiral pipe. The dust removal device is connected to the upper part of the furnace chamber and to the upper part of the cooling device.

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