A method and system for waste heat utilization of an open cycle roaster

Abstract

The present application relates to a kind of waste heat utilization method and system, especially to be applied in the waste heat utilization method and system of open ring type baking furnace of carbon industry production aluminum anode, cathode, electrode and carbon graphitization material.In need of heating, 150-200 ℃ medium temperature flue gas collected in the forced cooling zone of open ring type baking furnace is sent to adjacent green block storehouse of baking workshop for heating by air guide frame and main pipe, and in need of no heating, 150-200 ℃ medium temperature flue gas collected in the forced cooling zone of open ring type baking furnace is sent to low-temperature waste heat boiler to produce 40-60 ℃ medium temperature hot water for factory area.The present application has the advantages of: on the one hand, it solves the problem of high ambient temperature in workshop caused by direct flue gas discharge to workshop, which affects the failure of multifunctional vehicle, on the other hand, it collects the flue gas discharged from the forced cooling zone of baking furnace, maximizes the use of its heat, and achieves the effect of energy saving and consumption reduction.

Description

TECHNICAL FIELD

[0001] The present application relates to a waste heat utilization method and system, in particular to a waste heat utilization method and system applied to an open ring type baking furnace for producing anodes, cathodes, electrodes and carbon graphitization materials for aluminum industry. BACKGROUND

[0002] In recent years, the electrolytic aluminum industry has developed rapidly, driving the prebaked anode industry to develop rapidly and gradually form a large scale, from the previous 100,000 tons to the current 300,000 tons. As the last process of prebaked anode, the baking furnace is gradually becoming large-scale, which brings the problem of high environmental temperature in the workshop, affecting the normal operation of the multifunctional overhead crane.

[0003] The traditional baking process uses a blast stand to forcibly cool the high-temperature carbon blocks. The principle is that in the forced cooling area of the baking, the high-temperature carbon blocks are cooled by blowing in normal temperature air, but the high-temperature air (temperature 150-200℃) after heat exchange is directly discharged to the workshop through the fire hole, causing the environmental temperature in the workshop to be too high. In Xinjiang, the temperature in the overhead crane area is even as high as 70℃, which seriously affects production. Therefore, the induced draft type forced cooling process is applied to the baking process, which can solve the problem of carbon block secondary oxidation and reduce the environmental temperature in the workshop, and it is possible to recover the heat of the medium-temperature flue gas. SUMMARY

[0004] The present application is to solve the above technical problems and provides a waste heat utilization method and system, which aims to maximize the utilization of the heat in the collected medium-temperature flue gas and achieve the effect of energy saving and consumption reduction.

[0005] To achieve the above purpose, the waste heat utilization method of an open ring type baking furnace collects the 150-200℃ medium-temperature flue gas in the forced cooling area of the open ring type baking furnace and sends it to the adjacent green block store through the induced draft stand and the main pipeline for heating when heating is needed, and sends it to the low-temperature waste heat boiler to produce 40-60℃ medium-temperature hot water for the factory area when heating is not needed.

[0006] A waste heat utilization system of an open ring type baking furnace, comprising an open ring type baking furnace, the open ring type baking furnace is arranged in a baking workshop, a green block store is adjacent to the baking workshop, the medium-temperature flue gas in the forced cooling area of the open ring type baking furnace is introduced into the main pipeline fixed on the furnace surface through the induced draft stand, the main pipeline is connected with branch pipeline one and branch pipeline two respectively, branch pipeline one is connected with the radiator in the green block store, the end of branch pipeline one is connected with the outdoor fan, and branch pipeline two is connected with the low-temperature waste heat boiler arranged in the baking workshop and then connected with the outdoor fan.

[0007] The main pipeline is fixedly installed in the middle area of ​​the open ring-type roasting furnace. An ascending pipeline is installed on the main pipeline and connected to the induced draft frame. Branch pipeline butterfly valves are installed at the inlet of branch pipeline one and branch pipeline two to control the flow direction of the medium-temperature flue gas.

[0008] The number of rising pipes is half the number of chambers in the open-loop roasting furnace. Each chamber shares a rising pipe, and a butterfly valve is installed between the rising pipe and the main pipe.

[0009] After entering the raw block storage, the branch pipe goes around the raw block storage. A certain number of radiators are installed on the branch pipe to provide heating using the heat from the flue gas.

[0010] The fan is connected to the flue gas exhaust pipe.

[0011] The main pipeline, branch pipeline one, and branch pipeline two are insulated.

[0012] Advantages and effects of the present invention:

[0013] This invention solves the problem of excessively high workshop temperatures caused by direct exhaust of flue gas into the workshop, which in turn affects the failure of multi-functional vehicles. On the other hand, it centrally collects the flue gas discharged from the forced cooling zone of the roasting furnace, maximizing the utilization of its heat and achieving energy saving and consumption reduction. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the waste heat utilization system of the present invention.

[0015] Figure 2 for Figure 1 Sectional view of AA.

[0016] In the diagram: 1. Roasting workshop; 2. Raw block storage; 3. Open ring roasting furnace; 4. Exhaust fan frame; 5. Main pipeline; 6. Ascending pipeline; 7. Ascending pipeline butterfly valve; 8. Branch pipeline butterfly valve; 9. Branch pipeline one; 10. Branch pipeline two; 11. Radiator; 12. Low-temperature waste heat boiler; 13. Fan; 14. Flue gas exhaust pipeline. Detailed Implementation

[0017] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the embodiments.

[0018] This invention discloses a waste heat utilization method for an open-ring roasting furnace. When heating is required, the 150-200℃ medium-temperature flue gas collected in the forced cooling zone of the open-ring roasting furnace 3 is introduced through the induced draft frame 4 and the main pipeline 5 to the raw block warehouse 2 adjacent to the roasting workshop 1 for heating. When heating is not required, the 150-200℃ medium-temperature flue gas collected in the forced cooling zone of the open-ring roasting furnace 3 is introduced through the induced draft frame 4 and the main pipeline 5 to the low-temperature waste heat boiler 12 to produce 40-60℃ medium-temperature hot water for use in the plant area.

[0019] As shown in the figure, a waste heat utilization system for an open-ring roasting furnace includes an open-ring roasting furnace 3, which is located in a roasting workshop 1. A raw block storage 2 is adjacent to the roasting workshop 1. The medium-temperature flue gas from the forced cooling zone of the open-ring roasting furnace 3 is introduced into a main pipe 5 fixed on the furnace surface through an induced draft frame 4. The main pipe 5 is connected to branch pipe 9 and branch pipe 10 respectively. Branch pipe 9 enters the raw block storage 2 and connects to a radiator 11 inside the raw block storage 2. The end of branch pipe 9 is connected to an outdoor fan 13. Branch pipe 10 is connected to a low-temperature waste heat boiler 12 located in the roasting workshop 1 and then connected to the outdoor fan 13.

[0020] The main pipe 5 is fixedly installed in the middle area of ​​the open ring roasting furnace 3. An ascending pipe 6 is installed on the main pipe 5 and connected to the induced draft frame 4. Branch pipe butterfly valves 8 are installed at the inlet of branch pipe 1 9 and branch pipe 2 10 to control the flow direction of the medium temperature flue gas.

[0021] The number of rising pipes 6 is half the number of furnace chambers in the open ring roasting furnace 3. Each furnace chamber shares a rising pipe 6, and a rising pipe butterfly valve 7 is installed between the rising pipe 6 and the main pipe 5.

[0022] After entering the raw block storage 2, the branch pipe 9 surrounds the raw block storage 2. A certain number of radiators are installed on the branch pipe 9 to provide heating using the heat in the flue gas.

[0023] The fan 13 is connected to the flue gas exhaust pipe 14.

[0024] The main pipe 5, branch pipe 1 9 and branch pipe 2 10 are insulated.

Claims

1. A waste heat utilization system for an open-ring roasting furnace, characterized in that... The system includes an open-loop roasting furnace located in the roasting workshop, with the raw block storage adjacent to the workshop. The medium-temperature flue gas from the forced cooling zone of the open-loop roasting furnace is introduced into a fixed main pipe on the furnace surface via an induced draft frame. This main pipe connects to branch pipe one and branch pipe two. Branch pipe one enters the raw block storage and connects to radiators within it. The end of branch pipe one connects to an outdoor fan. Branch pipe two connects to a low-temperature waste heat boiler located in the roasting workshop and then to an outdoor fan. When heating is required, the 150-200℃ medium-temperature flue gas collected in the forced cooling zone of the open-loop roasting furnace is delivered to the adjacent raw block storage via the induced draft frame and main pipe for heating. When heating is not required, the flue gas collected in the forced cooling zone of the open-loop roasting furnace... The collected 150-200℃ medium-temperature flue gas is guided to a low-temperature waste heat boiler via an induced draft fan and main pipeline to produce 40-60℃ medium-temperature hot water for use in the plant area. The main pipeline is fixedly installed in the middle area of ​​the open ring roasting furnace surface. An ascending pipe is installed on the main pipeline and connected to the induced draft fan. Branch pipe butterfly valves are installed at the inlet of branch pipe one and branch pipe two to control the flow direction of the medium-temperature flue gas. The number of ascending pipes is half the number of furnace chambers in the open ring roasting furnace. Opposite furnace chambers share one ascending pipe. An ascending pipe butterfly valve is installed between the ascending pipe and the main pipeline. After entering the raw block storage, branch pipe one surrounds the raw block storage. A certain number of radiators are installed on branch pipe one to use the heat in the flue gas for heating.

2. The waste heat utilization system of an open-ring roasting furnace according to claim 1, characterized in that... The fan is connected to the flue gas exhaust pipe.

3. The waste heat utilization system of an open-ring roasting furnace according to claim 1, characterized in that... The main pipeline, branch pipeline one, and branch pipeline two are insulated.

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