Rotary kiln roasting flue gas waste heat recovery system in reduced titanium production process

Abstract

The utility model discloses a rotary kiln roasting flue gas waste heat recovery system in reduced titanium production process, which comprises a waste heat recovery device and a power generation device, the waste heat recovery device comprises a rotary kiln, a settling chamber and a waste heat boiler, and the output end of the rotary kiln is connected with the input end of the settling chamber through a corresponding pipeline. The interior of the settling chamber is closed to form a heat preservation space used for conducting heat preservation on smoke, and the output end of the settling chamber is connected with the input end of a heat exchange pipeline of the waste heat boiler through a corresponding pipeline. The top of the waste heat boiler is provided with a steam conveying pipeline communicated with the upper area in the waste heat boiler, and the output end of the steam conveying pipeline is connected with the input end of the power generation device. Softened water in the waste heat boiler exchanges heat with flue gas in the heat exchange pipeline, and maximum recovery of high-temperature waste heat in the flue gas discharged by the rotary kiln is achieved through efficient heat energy recovery devices such as the integrated settling chamber, the waste heat boiler and the steam turbine generator unit. Compared with a traditional mode of direct air cooling, the system has the advantages that the energy utilization efficiency is remarkably improved, and energy waste is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of rotary kilns, in particular to a waste heat recovery system for the roasting flue gas of a rotary kiln during the production of reduced titanium. Background Technique

[0002] A rotary kiln refers to a rotary calcination kiln (commonly known as a rotary kiln), whose shape is similar to a rotating bed, also called a rotating bed kiln, belonging to the building materials equipment category. Rotary kilns can be divided into cement kilns, metallurgical and chemical kilns, and lime kilns according to the different materials to be processed.

[0003] When the rotary kiln is roasting for the production of reduced titanium, the high-temperature flue gas (up to 950 °C) generated contains pollutants such as CO, CO 2 , SO 2 and coal ash. In the traditional treatment process, after the flue gas is air-cooled to about 200 °C in the sedimentation chamber, it is then discharged after dust removal and desulfurization treatment. During this process, a large amount of heat energy is not effectively recovered, which not only wastes energy but also causes heat pollution problems.

[0004] The existing rotary kiln flue gas in the prior art lacks measures for recovering and utilizing waste heat, and mainly has the following problem points:

[0005] 1. The current technology relies on the combination of a sedimentation chamber and a fan to cool the flue gas as high as 950 °C to about 220 °C, which wastes electric energy and heat energy in this process.

[0006] 2. The cooling efficiency of the combination of the sedimentation chamber and the fan is limited, resulting in large temperature fluctuations, affecting the normal operation of dust removal and desulfurization equipment, and thus causing excessive emissions.

[0007] 3. The high-temperature flue gas is directly discharged through air cooling, and a large amount of heat energy is dissipated into the atmosphere, which not only wastes resources but also causes heat pollution, having a negative impact on the environment and the lives of residents. Content of the Utility Model

[0008] To solve the technical problems raised in the above background technique, the utility model provides a waste heat recovery system for the roasting flue gas of a rotary kiln during the production of reduced titanium.

[0009] The utility model is realized by adopting the following technical solutions: A waste heat recovery system for the roasting flue gas of a rotary kiln during the production of reduced titanium, including a waste heat recovery device and a power generation device. The waste heat recovery device includes a rotary kiln, a sedimentation chamber, and a waste heat boiler. The output end of the rotary kiln is connected to the input end of the sedimentation chamber through a corresponding pipeline. The inside of the sedimentation chamber is sealed to form a heat preservation space for heat preservation of the flue gas.

[0010] The output end of the sedimentation chamber is connected to the input end of the heat exchange pipeline of the waste heat boiler through a corresponding pipeline;

[0011] The top of the waste heat boiler is provided with a steam delivery pipeline communicating with the upper region inside it, and the output end of the steam delivery pipeline is connected to the input end of the power generation device;

[0012] Wherein, the softened water in the waste heat boiler exchanges heat with the flue gas in the heat exchange pipeline to absorb the waste heat of the flue gas and convert it into hot steam. The hot steam enters the power generation device through the steam delivery pipeline for the power generation device to generate electricity.

[0013] As a further improvement of the above solution, the waste heat recovery device further includes a blower, and the output end of the blower is communicated with the heat preservation space through a corresponding pipeline.

[0014] As a further improvement of the above solution, the power generation device includes a steam turbine generator set, and the steam input end of the steam turbine generator set is connected to the output end of the steam delivery pipe.

[0015] As a further further improvement of the above solution, the power generation device further includes a cooling tower. The input end of the cooling tower is connected to the output end of the heat dissipation pipeline of the steam turbine generator set through a corresponding pipeline, and the output end of the cooling tower is connected to the input end of the heat dissipation pipeline of the steam turbine generator set through a corresponding pipeline.

[0016] As a further further improvement of the above solution, the system further includes a softened water circulation device. The softened water circulation device includes a softened water tank and a deaerator. The output end of the softened water tank is connected to one of the input ends of the deaerator through a corresponding pipeline. The output end of the deaerator is connected to the inside of the waste heat boiler through a corresponding pipeline. The other input end of the deaerator is connected to the condensate output end of the steam turbine generator set through a corresponding pipeline.

[0017] As a further further improvement of the above solution, a feed water pump is installed on the corresponding pipeline between the softened water tank and the deaerator, and a feed water pump is installed on the corresponding pipeline between the deaerator and the waste heat boiler.

[0018] As a further improvement of the above solution, the system further includes a flue gas purification device. The flue gas purification device includes a dust collector and a desulfurization tower. The input end of the dust collector is connected to the inside of the waste heat boiler through a corresponding pipeline, and the output end of the dust collector is connected to the output end of the desulfurization tower through a corresponding pipeline.

[0019] As a further further improvement of the above solution, an induced draft fan is installed on the corresponding pipeline between the dust collector and the desulfurization tower.

[0020] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0021] 1. The utility model realizes the maximum recovery of high-temperature waste heat in the flue gas discharged from the rotary kiln by integrating high-efficiency waste heat recovery devices such as a sedimentation chamber, a waste heat boiler, and a steam turbine generator set. Compared with the traditional direct air cooling method, the utility model significantly improves the energy utilization efficiency and reduces energy waste.

[0022] 2. Through waste heat power generation, the utility model not only reduces the dependence on external power but also creates additional economic benefits. The electric energy generated can be used in multiple fields in the factory area, such as office, production, and living, effectively reducing the operation cost of the enterprise and improving the overall economic efficiency.

[0023] 3. The system of the utility model aims to efficiently recover the waste heat in the flue gas of the rotary kiln, convert it into electric energy, and at the same time reduce the flue gas temperature and pollutants to meet the environmental protection requirements of the emission standards, reduce thermal pollution, improve the energy utilization efficiency, and provide office and living electricity for the factory area, realizing energy conservation, emission reduction, and resource recycling. Description of the Drawings

[0024] Figure 1 It is the overall schematic diagram of the system of the utility model.

[0025] Main Symbol Description:

[0026] 1. Rotary kiln; 2. Sedimentation chamber; 3. Waste heat boiler; 4. Blower; 5. Steam turbine generator set; 6. Cooling tower; 7. Soft water tank; 8. Deaerator; 9. Feed water pump; 10. Dust collector; 11. Desulfurization tower; 12. Induced draft fan. Detailed Embodiment

[0027] Next, in combination with the drawings and specific embodiments, the utility model will be further described. It should be noted that on the premise of no conflict, the following-described embodiments or technical features can be arbitrarily combined to form new embodiments.

[0028] Please combine Figure 1 , the waste heat recovery system for the rotary kiln roasting flue gas during the production of reduced titanium. The system consists of core components such as a rotary kiln 1, a sedimentation chamber 2, a blower 4, a waste heat boiler 3, several feed water pumps 9, a soft water tank 7, a deaerator 8, a steam turbine generator set 5, a dust collector 10, an induced draft fan 12, and a desulfurization tower 11. Each component is tightly connected by pipelines to form a closed-loop waste heat recovery and power generation process. Specifically:

[0029] The system includes a waste heat recovery device and a power generation device. The waste heat recovery device includes a rotary kiln 1, a sedimentation chamber 2, and a waste heat boiler 3. The output end of the rotary kiln 1 is connected to the input end of the sedimentation chamber 2 through corresponding pipelines. The inside of the sedimentation chamber 2 is enclosed to form a heat preservation space for heat preservation of the flue gas.

[0030] The output end of the settling chamber 2 is connected to the input end of the heat exchange pipes of the waste heat boiler 3 through corresponding pipes;

[0031] The top of the waste heat boiler 3 is provided with a steam delivery pipe communicating with the upper region inside it, and the output end of the steam delivery pipe is connected to the input end of the power generation device.

[0032] Among them, the softened water in the waste heat boiler 3 exchanges heat with the flue gas in the heat exchange pipes to absorb the waste heat of the flue gas and convert it into hot steam. This hot steam enters the power generation device through the steam delivery pipe for the power generation device to generate electricity.

[0033] The waste heat recovery device further includes a blower 4, and the output end of the blower 4 is connected to the heat preservation space through corresponding pipes.

[0034] The power generation device includes a steam turbine generator set 5, and the steam input end of the steam turbine generator set 5 is connected to the output end of the steam delivery pipe.

[0035] The power generation device further includes a cooling tower 6. The input end of the cooling tower 6 is connected to the output end of the heat dissipation pipe of the steam turbine generator set 5 through corresponding pipes, and the output end of the cooling tower 6 is connected to the input end of the heat dissipation pipe of the steam turbine generator set 5 through corresponding pipes.

[0036] Through the cooling tower 6, the temperature of the steam turbine generator set 5 can be prevented from being too high, ensuring that the steam turbine generator set 5 operates stably.

[0037] The system further includes a softened water circulation device. The softened water circulation device includes a softened water tank 7 and a deaerator 8. The output end of the softened water tank 7 is connected to one of the input ends of the deaerator 8 through corresponding pipes, the output end of the deaerator 8 is connected to the inside of the waste heat boiler 3 through corresponding pipes, and the other input end of the deaerator 8 is connected to the condensate output end of the steam turbine generator set 5 through corresponding pipes.

[0038] A feed water pump 9 is installed on the corresponding pipe between the softened water tank 7 and the deaerator 8, and a feed water pump 9 is installed on the corresponding pipe between the deaerator 8 and the waste heat boiler 3.

[0039] The system further includes a flue gas purification device. The flue gas purification device includes a dust collector 10 and a desulfurization tower 11. The input end of the dust collector 10 is connected to the inside of the waste heat boiler 3 through corresponding pipes, and the output end of the dust collector 10 is connected to the output end of the desulfurization tower 11 through corresponding pipes.

[0040] An induced draft fan 12 is installed on the corresponding pipe between the dust collector 10 and the desulfurization tower 11.

[0041] The working steps of this system are as follows:

[0042] S1: According to the characteristics of the rotary kiln flue gas, a waste heat recovery device, a power generation device, a softened water circulation device and a flue gas purification device are designed.

[0043] S2: The flue gas of the rotary kiln 1 undergoes a combustion reaction and temperature rise in the sedimentation chamber 2, and high-temperature steam is obtained through efficient heat exchange with softened water in the waste heat boiler 3.

[0044] S3: The high-temperature and high-pressure steam generated by the waste heat boiler 3 drives the steam turbine generator set 5 to be converted into electric energy for use in the factory area for office and living, realizing the green cycle and efficient utilization of energy.

[0045] S4: The softened water tank 7 replenishes water and conducts system water circulation.

[0046] S5: The flue gas is discharged into the atmosphere after purification treatment.

[0047] Furthermore, the detailed steps of step S2 are as follows:

[0048] S21: The high-temperature flue gas (about 950 °C, 50,000 standard cubic meters) of the rotary kiln 1 enters the sedimentation chamber 2 through the corresponding pipeline. The blower 4 precisely regulates the air input to promote the reaction of carbon monoxide and oxygen, generating carbon dioxide and significantly raising the temperature to 1050 °C, improving the waste heat quality.

[0049] S22: The high-temperature flue gas enters the waste heat boiler 3 from the sedimentation chamber 2 through the corresponding pipeline and conducts efficient heat exchange with the softened water, causing the softened water to generate high-temperature and high-pressure steam. At the same time, the flue gas temperature drops to the temperature range (180 °C - 220 °C) that can be handled by the bag filter 10.

[0050] Furthermore, the detailed steps of step S4 are as follows:

[0051] S41: The condensed water discharged from the steam turbine generator set 5 after the hot steam generated by the waste heat boiler 3 passes through the deaerator 8 for reprocessing, and then is pumped into the waste heat boiler 3 through the corresponding feed water pump 9 to form a deaerated water circulation, reducing water resource consumption.

[0052] S42: The softened water tank 7 continuously replenishes water (keeping the system water volume sufficient). After being deaerated by the deaerator 8 (the softened water undergoes deaeration treatment by the deaerator 8 to prevent corrosion in the boiler and improve the steam quality), it is sent into the waste heat boiler 3 through the corresponding feed water pump 9 to participate in heat exchange.

[0053] Furthermore, the detailed steps of step S5 are as follows:

[0054] S51: The cooled flue gas enters the dust collector 10, and after deep dust removal treatment, it is sent into the desulfurization tower 11 through the induced draft fan 12.

[0055] S52: The flue gas after dust removal is sent into the desulfurization tower 11 through the induced draft fan 12. The sulfur oxides in the flue gas are effectively removed by the desulfurization tower 11, and the flue gas temperature is further reduced to about 100 °C, meeting the environmental protection emission standards.

[0056] That is to say, the heat of the flue gas of the rotary kiln 1 can be used for heat exchange between the boiler and softened water to generate steam for power generation, reducing the enterprise's dependence on external power and creating additional economic benefits for the enterprise. The electric energy obtained from power generation can be used in multiple fields such as factory office, production and life, effectively reducing the enterprise's operating costs.

[0057] The above-mentioned embodiments are only the preferred embodiments of the present invention, and the scope of protection of the present invention cannot be limited thereby. Any non-substantive changes and substitutions made by those skilled in the art on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. A system for recovering waste heat from rotary kiln roasting flue gas in the process of producing reduced titanium, characterized in that: It includes a waste heat recovery device and a power generation device. The waste heat recovery device includes a rotary kiln, a settling chamber and a waste heat boiler. The output end of the rotary kiln is connected to the input end of the settling chamber through a corresponding pipeline. The interior of the settling chamber is sealed to form an insulation space for heat preservation of flue gas. The output end of the settling chamber is connected to the input end of the heat exchange pipe of the waste heat boiler through a corresponding pipe; The top of the waste heat boiler is provided with a steam delivery pipeline connected to the upper area inside the waste heat boiler, and the output end of the steam delivery pipeline is connected to the input end of the power generation device; The softened water in the waste heat boiler exchanges heat with the flue gas in the heat exchange pipe to absorb the waste heat of the flue gas and convert it into hot steam. The hot steam enters the power generation device through the steam delivery pipe to generate electricity for the power generation device.

2. The rotary kiln roasting flue gas waste heat recovery system in the process of producing and reducing titanium according to claim 1, characterized in that: The waste heat recovery device also includes a blower, and the output end of the blower is connected to the heat preservation space through a corresponding pipeline.

3. The system for recovering waste heat from rotary kiln roasting flue gas in the process of producing and reducing titanium according to claim 1, characterized in that: The power generation device comprises a steam turbine generator set, and the steam input end of the steam turbine generator set is connected to the output end of the steam delivery pipe.

4. The system for recovering waste heat from rotary kiln roasting flue gas in the process of producing and reducing titanium according to claim 3, characterized in that: The power generation device also includes a cooling tower, the input end of the cooling tower is connected to the output end of the heat dissipation pipeline of the steam turbine generator set through a corresponding pipeline, and the output end of the cooling tower is connected to the input end of the heat dissipation pipeline of the steam turbine generator set through a corresponding pipeline.

5. The system for recovering waste heat from rotary kiln roasting flue gas in the process of producing and reducing titanium according to claim 3, characterized in that: The system also includes a softened water circulation device, which includes a softened water tank and a deaerator. The output end of the softened water tank is connected to one of the input ends of the deaerator through a corresponding pipeline, the output end of the deaerator is connected to the inside of the waste heat boiler through a corresponding pipeline, and the other input end of the deaerator is connected to the condensate output end of the steam turbine generator set through a corresponding pipeline.

6. The system for recovering waste heat from rotary kiln roasting flue gas in the process of producing and reducing titanium according to claim 5, characterized in that: A feed water pump is installed on the corresponding pipeline between the softened water tank and the deaerator, and a feed water pump is installed on the corresponding pipeline between the deaerator and the waste heat boiler.

7. The system for recovering waste heat from rotary kiln roasting flue gas in the process of producing and reducing titanium according to claim 1, characterized in that: The system also includes a flue gas purification device, which includes a dust collector and a desulfurization tower. The dust collector input end is connected to the inside of the waste heat boiler through a corresponding pipeline, and the dust collector output end is connected to the desulfurization tower output end through a corresponding pipeline.

8. The system for recovering waste heat from rotary kiln roasting flue gas in the process of producing and reducing titanium according to claim 7, characterized in that: An induced draft fan is installed on the corresponding pipeline between the dust collector and the desulfurization tower.

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