Process and device for producing secondary zinc oxide calcine

Abstract

The embodiment of the invention relates to a production process and device for secondary zinc oxide calcine, and belongs to the technical field of zinc calcine production. According to the production process and device of the secondary zinc oxide calcine, the device comprises a hollow decomposing furnace, the bottom of the decomposing furnace is connected with a rotary kiln, the upper end of the decomposing furnace is connected with a three-way pipe valve, the upper end and the lower end of the decomposing furnace are closed up, a combustor is installed at the lower end of the decomposing furnace, and one end of the three-way pipe valve is connected with a fifth calcining cyclone; the other end of the three-way pipe valve is connected with a carbonization furnace outer pipe, a plurality of carbonization smoke pipes are installed in a smoke pipe of the carbonization furnace, the upper portion of the end, away from the fifth calcining cyclone, of the three-way pipe valve is communicated with the tangent line of the carbonization furnace outer pipe, and the other ends of the carbonization pipes are communicated with the lower end of the decomposing furnace. The device has the effect of reducing the production cost, the flue gas in the process of producing the secondary zinc oxide by the rotary kiln is used as a heat source, and the secondary zinc oxide is calcined by the multi-stage calcining cyclone to obtain the product zinc calcine.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of zinc roasted sand production, and in particular to a production process and device for zinc roasted sand of secondary zinc oxide. Background Art

[0002] Zinc roasted sand is the product obtained after roasting zinc concentrate. It is also the secondary zinc oxide recovered from zinc-containing solid waste through high-temperature reduction and oxidation. It is the product after roasting and decomposition to remove harmful impurities such as fluorine and chlorine. It mainly contains zinc oxide, zinc sulfate and trace zinc sulfide. It is mainly used for zinc smelting and is the most important raw material for zinc smelting. In order to reduce the import of zinc concentrate and reduce the pollution of zinc-containing solid waste to the environment, my country uses zinc-containing solid waste to produce secondary zinc oxide, and then uses rotary kiln and other calcining equipment to roast the secondary zinc oxide into zinc roasted sand. The production process will use a high-temperature environment for production.

[0003] In the prior art, zinc oxide is used as a raw material, and natural gas is used as the original heat energy to produce zinc roasted sand by spraying fire for heating. The zinc oxide powder material cannot form a suspension, the preheating calcination effect is poor, and heat energy is wasted. In addition, the produced zinc roasted sand is granular and blocky and must be ground before use, thereby increasing the production cost. Summary of the invention

[0004] In view of this, the embodiments of the present application provide a production process and device for secondary zinc oxide roasted sand to solve the technical problems raised by the background technology.

[0005] A first aspect of an embodiment of the present application provides a production device for secondary zinc oxide zinc roasted sand, comprising a decomposition furnace with a hollow interior, wherein a rotary kiln is connected to the bottom of the decomposition furnace, a three-way pipe valve is connected to the upper end of the decomposition furnace, the decomposition furnace is closed at the upper and lower ends, a burner is installed at the lower end of the decomposition furnace, one end of the three-way pipe valve is connected to a fifth calcining cyclone, the other end of the three-way pipe valve is connected to a flue pipe, a plurality of carbonization flue pipes are installed in the flue pipe, the carbonization flue pipe and the flue pipe constitute a carbonization furnace, and the three-way pipe valve is away from the fifth calcining cyclone. The upper part of one end of the blower is interconnected with the tangent of the outer pipe of the carbonization furnace, the other end of the multiple carbonization flue gas pipes is interconnected with the lower end of the decomposition furnace, the second calcination cyclone is connected above the fourth calcination cyclone, the third calcination cyclone is connected above the fifth calcination cyclone, the first calcination cyclone is connected to the third calcination cyclone, the third calcination cyclone is connected to the fourth calcination cyclone, and the fourth calcination cyclone is connected to the fifth calcination cyclone.

[0006] In some embodiments that may include the above embodiments, a spherical material feed hopper and a spherical zinc-containing material discharger are connected to the carbonization furnace, and the spherical material feed hopper is interconnected with a plurality of heat exchange tubes in the carbonization furnace.

[0007] In some embodiments that may include the above embodiments, the first calcination cyclone and the second calcination cyclone are connected to each other through a connecting pipe, a second feed hopper is installed on the connecting pipe, and a liquid spray nozzle is connected to a corner of the connecting pipe.

[0008] In some embodiments that may include the above embodiments, a grate cooler is connected to one end of the rotary kiln away from the decomposition furnace, and a tertiary high-temperature air duct is connected between the grate cooler and the decomposition furnace.

[0009] In some embodiments that may include the above embodiments, air valves are installed in both ends of the three-way pipe valve.

[0010] In some embodiments that may include the above-mentioned embodiments, a closed-air feeder is installed on the carbonization flue gas pipe, and the bottoms of the fifth calcination cyclone, the fourth calcination cyclone, the third calcination cyclone, the second calcination cyclone and the first calcination cyclone are all connected to the closed-air feeder, and the lower end of the carbonization flue gas pipe is installed with a closed-air feeder, and a plurality of the carbonization flue gas pipes pass through the material bin and the closed-air feeder and are interconnected with the lower end of the decomposition furnace.

[0011] In some embodiments that may include the above embodiments, the raw materials fed into the spherical material feeding hopper are spherical materials made by mixing zinc-containing solid waste, waste tire residue and biomass waste residue.

[0012] In some embodiments, which may include the above embodiments, the raw material fed into the second feeding hopper is a zinc oxide powder raw material.

[0013] The second aspect of the embodiment of the present application further provides a production process of secondary zinc oxide zinc roasted sand, using the production device of secondary zinc oxide zinc roasted sand, comprising the following steps:

[0014] When the staff needs to produce zinc roasted sand, the staff puts the material into the device through the spherical material feed hopper on the carbonization furnace; then, the material enters the lower part of the decomposition furnace and passes through the bottom of the decomposition furnace into the rotary kiln for processing. At this time, the processed material is converted into zinc vapor and then enters the decomposition furnace from the rotary kiln and is heated to 800 degrees by the burner, and the dust settles back into the rotary kiln; then, the heated zinc vapor enters the upper part, and at this time the flue gas is divided into two paths and enters the fifth calcination cyclone; then, the flue gas simultaneously enters the carbonization flue gas pipe and the carbonization furnace composed of the heat exchange tubes in the flue gas pipe, then enters the fifth calcination cyclone, then enters the fourth calcination cyclone, then enters the third calcination cyclone and the second calcination cyclone, and at this time the staff feeds the material to the spherical material feed hopper through the second feed hopper. Purchased secondary zinc oxide is added into the device to cool the flue gas, and the flue gas is sucked into the first calcination cyclone under the condition of suspended reverse heat exchange. In this process, the zinc vapor in the flue gas will be mixed with the added secondary zinc oxide; then, the flue gas is discharged through the first calcination cyclone, and the secondary zinc oxide passes through the first calcination cyclone and is calcined into zinc roasted sand in the second calcination cyclone, the third calcination cyclone and the fourth calcination cyclone in turn, and then is discharged through the fourth calcination cyclone and enters the finished product warehouse through the conveying equipment; if the cement clinker production capacity is withdrawn, the cement clinker production line does not need to be equipped with a tee pipe, and multiple heat exchange material pipes can be directly installed in the vertical section of the flue gas pipe that is tangentially connected to the fifth calcination cyclone at the outlet of the decomposition furnace, forming the same as the carbonization furnace.

[0015] Compared with the prior art, the embodiments of the present application have the following beneficial effects:

[0016] 1. In this application, when the staff needs to produce zinc roasted sand, the staff puts the material into the device through the spherical material feed hopper on the carbonization furnace. Subsequently, the material enters the lower part of the decomposition furnace and passes through the bottom of the decomposition furnace into the rotary kiln for processing. At this time, the processed material is converted into zinc vapor and enters the decomposition furnace from the rotary kiln and is heated to 800 degrees by the burner (the dust settles back into the rotary kiln). Subsequently, the heated flue gas enters the upper part. At this time, the flue gas enters the fifth calcination cyclone in two ways. The flue gas enters the carbonization flue gas pipe at the same time, and the spherical material is sent to the bottom of the decomposition furnace by controlling the feeding speed through the closed air feeder. The flue gas is combined with the flue gas before entering the fifth calcination cyclone and enters the fifth calcination cyclone. At this time, the staff adds the purchased secondary zinc oxide into the device through the second feed hopper to cool the flue gas, and then enters the first calcination cyclone under the condition of suspended reverse heat exchange. During this process, the zinc vapor in the flue gas will be mixed with the added secondary zinc oxide to recover most of the zinc oxide. Subsequently, the flue gas is discharged through the first calcination cyclone, and the secondary zinc oxide passes through the first calcination cyclone, passes through the second calcination cyclone, the third calcination cyclone and the fourth calcination cyclone in sequence to be calcined into zinc roasted sand, and then is discharged through the fourth calcination cyclone. In this process, the zinc roasted sand produced by utilizing the waste heat is directly in a ground state, thereby reducing the production cost;

[0017] 2. In this application, after the rotary kiln processing, the material will leave residues. The grate cooler recycles the residues, thereby reducing the difficulty of the staff to recycle the residues, thereby reducing the difficulty of the staff's work;

[0018] 3. In the present application, the electric air valve adjusts the air volume at both ends and reduces the difficulty of opening and closing for the staff, thereby reducing the workload of the staff. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A schematic diagram of the production process of an embodiment of the present application;

[0021] Figure 2 This is a schematic diagram of the structure of the decomposition furnace in the embodiment of the present application;

[0022] Figure 3 This is a schematic diagram of the cross-sectional structure of the decomposition furnace and the three-way pipe valve in the embodiment of the present application;

[0023] Figure 4 It is a schematic diagram of the structure of the connecting pipe and the second feed hopper in the embodiment of the present application.

[0024] Description of reference numerals:

[0025] 1. Decomposition furnace; 11. Rotary kiln; 12. Three-way pipe valve; 13. Burner; 2. Fifth calcination cyclone; 21. Fourth calcination cyclone; 22. Third calcination cyclone; 23. Second calcination cyclone; 24. First calcination cyclone; 25. Carbonization flue gas pipe; 3. Spherical material feed hopper; 4. Connecting pipe; 41. Second feed hopper; 42. Air-locking discharger; 5. Grate cooler; 6. Air valve; 7. Tertiary high-temperature air duct; 12-1. Carbonization furnace; 12-2 Flue gas pipe. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0027] First, those skilled in the art should understand that these implementations are only used to explain the technical principles of the present application and are not intended to limit the scope of protection of the present application. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.

[0028] Secondly, it should be noted that in the description of the present application, terms such as "up", "down", "left", "right", "front", "back", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the present application.

[0029] like Figure 1-4 As shown, the embodiment of the present application provides a production process and device for secondary zinc oxide roasted sand, including a decomposition furnace 1, a rotary kiln 11, a three-way pipe valve 12, a burner 13, a fifth calcination cyclone 2, a fourth calcination cyclone 21, a third calcination cyclone 22, a second calcination cyclone 23, a first calcination cyclone 24, a spherical material feed hopper 3, a connecting pipe 4 and a second feed hopper 41. The interior of the decomposition furnace 1 is hollow, the rotary kiln 11 is connected to the bottom of the decomposition furnace 1, the three-way pipe valve 12 is connected to the upper end of the decomposition furnace 1, and the decomposition furnace 1 is closed at the upper and lower ends. The burner 13 is installed at the lower end of the decomposition furnace 1, one end of the three-way pipe valve 12 is connected to the fifth calcining cyclone 2, and the other end of the three-way pipe valve 12 is connected to the flue pipe 12-2. A plurality of carbonization flue pipes 25 are installed in the flue pipe 12-2. The carbonization flue pipe 25 and the flue pipe 12-2 constitute a carbonization furnace 12-1, and the upper end of the three-way pipe valve 12 away from the fifth calcining cyclone 2 is interconnected with the tangent of the outer tube of the carbonization furnace 12-1, and the other ends of the plurality of carbonization flue pipes 25 are interconnected with the lower end of the decomposition furnace 1, and the outer tube of the carbonization furnace merges with the flue pipe at the other end and tangently enters the fifth calcining cyclone. The second calcination cyclone 23 is connected above the fourth calcination cyclone 21 of the cyclone, the third calcination cyclone 22 is connected above the fifth calcination cyclone 2, the first calcination cyclone 24 is connected above the second calcination cyclone 23, the first calcination cyclone 24 and the third calcination cyclone 22 are interconnected, and the third calcination cyclone 22 and the fourth calcination cyclone 21 are interconnected, and the fourth calcination cyclone 21 and the fifth calcination cyclone are interconnected.

[0030] In some specific embodiments, the spherical material feed hopper 3 is connected to the multiple heat exchange tubes 25 in the carbonization furnace 12-1 for feeding the spherical material, and the spherical material feed hopper 3 is interconnected with the multiple heat exchange tubes 25 in the carbonization furnace 12-1.

[0031] In some specific embodiments, the connecting pipe 4 is a circular tubular structure, the first calcining cyclone 24 and the second calcining cyclone 23 are connected to each other through the connecting pipe 4, and a liquid spray nozzle is connected to the corner of the connecting pipe 4. The second feed hopper 41 is installed on the connecting pipe 4 for feeding powder materials.

[0032] When the staff needs to produce zinc roasted sand, the staff puts the material into the device through the spherical material feed hopper 3 on the carbonization furnace 12-1. Subsequently, the material enters the lower part of the decomposition furnace 1 and passes through the bottom of the decomposition furnace 1 to enter the rotary kiln 11 for processing. At this time, the processed material is converted into zinc vapor and enters the decomposition furnace 1 from the rotary kiln 11 and is heated to 800 degrees by the burner 13 (the dust settles back into the rotary kiln 11). Subsequently, the heated zinc vapor enters the upper part. At this time, the flue gas enters the fifth calcination cyclone 2 in two ways. The flue gas simultaneously enters the carbonization flue gas pipe 25, then enters the fifth calcination cyclone 2, then enters the fourth calcination cyclone 21, then enters the third calcination cyclone 22 and the second calcination cyclone 23. At this time, the staff adds the purchased secondary zinc oxide into the device through the second feed hopper 41 to cool the flue gas, and then enters the first calcination cyclone 24 under the condition of suspended reverse heat exchange. In this process, the zinc vapor in the flue gas will be mixed with the added secondary zinc oxide to recover most of the zinc oxide. Subsequently, the flue gas is discharged through the first calcination cyclone 24, and the secondary zinc oxide is calcined into zinc roasted sand in the second calcination cyclone 23, the third calcination cyclone 22 and the fourth calcination cyclone 21 through the first calcination cyclone 24, and then discharged through the fourth calcination cyclone 21, and enters the finished product warehouse through the conveying equipment; if it is a factory that withdraws from the cement clinker production capacity, the cement clinker production line does not need to be equipped with a three-way pipe, and multiple heat exchange material pipes can be directly installed in the vertical section pipe of the flue gas pipe connected to the fifth calcination cyclone at the outlet of the decomposition furnace and the tangent line of the flue gas pipe to form the same as the carbonization furnace 12-1. In this process, the zinc roasted sand produced by using waste heat is directly in the state of fine sand powder after grinding, thereby reducing the production cost.

[0033] In some specific embodiments, the end of the rotary kiln 11 away from the decomposition furnace 1 is connected to a grate cooler 5, and a tertiary high-temperature air duct 7 is connected between the grate cooler 5 and the decomposition furnace 1. After the material is processed in the rotary kiln 11, residues will be left. The grate cooler 5 recycles the residues, thereby reducing the difficulty of the staff to recycle the residues, thereby reducing the difficulty of the staff's work. The high-temperature air recovered by the grate cooler 5 enters the decomposition furnace, and the entire flue gas is operated under negative pressure.

[0034] In some specific embodiments, electric air valves 6 are installed at both ends of the three-way pipe valve 12. The air valves 6 reduce the difficulty of the staff to open and close the three-way, and can adjust the air volume at both ends, thereby reducing the difficulty of the staff (adjusting the air volume at both ends). In addition, cement production can be switched, thereby improving the practicality of the device.

[0035] In some specific embodiments, a closed air feeder 42 is installed on the carbonization flue gas pipe 25, and the bottoms of the fifth calcination cyclone 2, the fourth calcination cyclone 21, the third calcination cyclone 22, the second calcination cyclone 23 and the first calcination cyclone 24 are all connected with a closed air feeder 42, and the lower end of the carbonization flue gas pipe 25 is installed with a closed air feeder 42, and a plurality of the carbonization flue gas pipes 25 pass through the material bin and the closed air feeder 42 and are interconnected with the lower end of the decomposition furnace 1. The closed air feeder 42 can control the feeding speed of the spherical material, thereby improving the practicality of the device.

[0036] The working principle of the production process and device of secondary zinc oxide calcined sand in the present embodiment is as follows:

[0037] When the staff needs to produce zinc roasted sand, the staff puts the material into the device through the spherical material feed hopper 3 on the carbonizing furnace 12-1. Subsequently, the material enters the lower part of the decomposition furnace 1 and passes through the bottom of the decomposition furnace 1 to enter the rotary kiln 11 for processing. At this time, the processed material is converted into zinc vapor and enters the decomposition furnace 1 from the rotary kiln 11 and is heated to 800 degrees by the burner 13 (the dust settles back into the rotary kiln). Subsequently, the heated zinc vapor enters the upper part. At this time, the flue gas enters the fifth calcination cyclone 2 in two ways. Subsequently, the flue gas enters the carbonization flue gas pipe (and the carbonization furnace 12-1 composed of the flue gas pipe and the heat exchange tube), the fifth calcination cyclone 2, the fourth calcination cyclone 21, the third calcination cyclone 22 and the second calcination cyclone 23 at the same time. At this time, the staff adds the purchased secondary zinc oxide into the device through the second feed hopper 41 to cool the flue gas, and then the flue gas is sucked into the first calcination cyclone 24 under the condition of suspended reverse heat exchange. During this process, the zinc vapor in the flue gas will mix with the added secondary zinc oxide. Subsequently, the flue gas is discharged through the first calcination cyclone 24, and the secondary zinc oxide is calcined into zinc roasted sand in the second calcination cyclone 23, the third calcination cyclone 22 and the fourth calcination cyclone 21 through the first calcination cyclone 24, and then discharged through the fourth calcination cyclone 21. During this process, the zinc roasted sand produced by using the waste heat is directly in the state of fine sand powder after grinding, thereby reducing the production cost.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A production device for zinc oxide roasted sand, comprising a hollow decomposition furnace (1), characterized in that: The bottom of the decomposition furnace (1) is connected to a rotary kiln (11), the upper end of the decomposition furnace (1) is connected to a three-way pipe valve (12), the decomposition furnace (1) is closed at the top and bottom, the lower end of the decomposition furnace (1) is installed with a burner (13), one end of the three-way pipe valve (12) is connected to a fifth calcining cyclone (2), the other end of the three-way pipe valve (12) is connected to a flue gas pipe (12-2), a plurality of carbonization flue gas pipes (25) are installed in the flue gas pipe (12-2), the carbonization flue gas pipe (25) and the flue gas pipe (12-2) form a carbonization furnace (12-1), the upper end of the three-way pipe valve (12) away from the fifth calcining cyclone (2) is connected to the carbonization furnace (12-1), and the upper end of the three-way pipe valve (12) is connected to the carbonization furnace (12-1). The outer pipes of the decomposition furnace are interconnected at tangent lines, the other ends of the multiple carbonization flue gas pipes (25) are interconnected with the lower end of the decomposition furnace (1), the fourth calcination cyclone (21) is connected to the second calcination cyclone (23) above, the fifth calcination cyclone (2) is connected to the third calcination cyclone (22) above, the second calcination cyclone (23) is connected to the first calcination cyclone (24) above, the first calcination cyclone (24) and the third calcination cyclone (22) are interconnected, the third calcination cyclone (22) and the fourth calcination cyclone (21) are interconnected, and the fourth calcination cyclone (21) and the fifth calcination cyclone (2) are interconnected.

2. The production device of a secondary zinc oxide calcine according to claim 1, characterized in that: The carbonization furnace (12-1) is connected to a spherical material feed hopper (3) and a spherical zinc-containing material discharger, and the spherical material feed hopper (3) is interconnected with a plurality of heat exchange tubes in the carbonization furnace.

3. The production device of a secondary zinc oxide zinc roasted sand according to claim 1, characterized in that, The first calcining cyclone (24) and the second calcining cyclone (23) are connected to each other via a connecting pipe (4), a second feed hopper (41) is installed on the connecting pipe (4), and a liquid spray nozzle is connected to the corner of the connecting pipe (4).

4. The production device of a secondary zinc oxide calcine according to claim 1, characterized in that: The end of the rotary kiln (11) away from the decomposition furnace (1) is connected to a grate cooler (5), and a tertiary high-temperature air duct (7) is connected between the grate cooler (5) and the decomposition furnace (1).

5. The production device of a secondary zinc oxide calcine according to claim 1, characterized in that: Air valves (6) are installed at both ends of the three-way pipe valve (12).

6. The production device of a secondary zinc oxide zinc roasted sand according to claim 1, characterized in that: A closed-air feeder (42) is installed at the lower end of the carbonization flue gas pipe (25); the bottoms of the fifth calcination cyclone, the third calcination cyclone, the second calcination cyclone and the first calcination cyclone are all connected to a closed-air feeder (42); a closed-air feeder (42) is installed at the lower end of the carbonization flue gas pipe; a plurality of the carbonization flue gas pipes (25) pass through the material bin and the closed-air feeder (42) and are interconnected with the lower end of the decomposition furnace (1).

7. The production device of a secondary zinc oxide calcine according to claim 2, characterized in that: The raw materials fed into the spherical material feeding hopper (3) are spherical materials made by mixing zinc-containing solid waste, waste tire residue and biomass waste residue.

8. The production device of secondary zinc oxide calcined sand according to claim 3, characterized in that: The raw material fed into the second feeding hopper (41) is secondary zinc oxide powdery raw material.

9. A production process for zinc oxide roasted sand, characterized in that: The production device of secondary zinc oxide calcined sand according to any one of claims 1 to 8 comprises the following steps: When the staff needs to produce zinc roasted sand, the staff puts the material into the device through the spherical material feed hopper (3) on the carbonizing furnace (12-1); then, the material enters the lower part of the decomposition furnace (1) and passes through the bottom of the decomposition furnace (1) to enter the rotary kiln (11) for processing. At this time, the processed material is converted into zinc vapor and then enters the decomposition furnace (1) from the rotary kiln (11) and is heated to 800 degrees by the burner (13), and the dust settles back into the rotary kiln; then, the heated zinc vapor enters the upper part, and the smoke enters the fifth calcining cyclone (2) in two ways; Afterwards, the flue gas simultaneously enters the carbonization flue gas pipe and the carbonization furnace (12-1) composed of the heat exchange tubes in the flue gas pipe, then enters the fifth calcination cyclone (2), then enters the fourth calcination cyclone (21), then enters the third calcination cyclone (22) and the second calcination cyclone (23). At this time, the staff adds the purchased secondary zinc oxide into the device through the second feed hopper (41) to cool the flue gas, and then the flue gas is sucked into the first calcination cyclone (24) under the condition of suspended reverse heat exchange. In this process, the zinc vapor in the flue gas will mix with the added secondary zinc oxide; Subsequently, the flue gas is discharged through the first calcination cyclone (24), and the secondary zinc oxide passes through the first calcination cyclone (24) and passes through the second calcination cyclone (23), the third calcination cyclone (22) and the fourth calcination cyclone (21) in sequence to be calcined into zinc roasted sand, and then is discharged through the fourth calcination cyclone (21) and enters the finished product warehouse through the conveying equipment; if the cement clinker production capacity is withdrawn, the cement clinker production line does not need to be equipped with a three-way pipe, and multiple heat exchange material pipes can be directly installed in the vertical section of the flue gas pipe at the outlet of the decomposition furnace and the fifth calcination cyclone tangent to the flue gas pipe to form the same as the carbonization furnace (12-1).

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