A high-temperature oil-containing and dust-containing gas dust removal and filtration system overall preheating and starting system for pyrolysis

Abstract

The utility model relates to a kind of pyrolysis high-temperature oil-containing dust-containing gas dust removal filter system overall preheating and commissioning system and method, belong to coal pyrolysis technical field, specifically including pyrolysis device and the multistage dust removal filter connected by pyrolysis gas pipeline with pyrolysis device, the outlet end of multistage dust collector is connected with dust collector outlet pipeline, preheating and commissioning auxiliary device are connected on the multistage dust removal filter, the preheating and commissioning auxiliary device are used to in preheating section generation gas to the multistage dust removal filter and its connecting pipeline carry out overall preheating, and for in commissioning section for the multistage dust removal filter provides commissioning gas, the utility model can preheat dust removal filter system, can replace gas as commissioning gas, to reach the purpose of preheating dust removal system before commissioning, as commissioning gas when commissioning, greatly reduce the difficulty of commissioning.

Description

Technical Field

[0001] This utility model relates to an overall preheating and start-up system for a high-temperature oily and dusty gas dust removal and filtration system for pyrolysis, belonging to the field of coal pyrolysis technology. Background Technology

[0002] Low-rank coal pyrolysis at low temperatures produces coal tar with a high carbon-to-hydrogen ratio and a relatively high content of unsaturated olefins. Therefore, during medium- and low-temperature pyrolysis, the high-temperature coal gas will undergo physical and chemical changes when it encounters a medium temperature lower or higher than that used for coal gas pyrolysis. When encountering a low-temperature medium, the tar gas in the coal gas will condense and precipitate, that is, liquid coal tar will appear on the medium and eventually coke. When encountering a high-temperature medium, the coal tar gas in the coal gas will undergo partial thermal decomposition, that is, some of the tar gas will break down into lighter and larger molecules. The lighter molecules are coal gas or lighter coal tar, while the larger molecules are heavier tar, or even carbon. Therefore, when coal gas enters the dust removal and filtration system, if the filter temperature is low, tar will condense in the filter, which easily adheres to dust and quickly clogs the filter body. If the filter encounters local high temperatures, the tar gas undergoes deep pyrolysis and coking, turning gaseous substances into solid coking substances. This easily leads to deposition in the micropores of the filter body and in the micropores of the filter cake formed on the filter body surface, causing micropore blockage. This results in a rapid increase in the gas pressure difference before and after the filter body, and a rapid decrease in filtration capacity. In addition, the condensation of unsaturated olefins makes the tar molecules larger, and the gaseous state easily turns into a liquid state. This also makes it easy to adhere to dust, causing the filter cake to thicken rapidly. Furthermore, liquid tar easily clogs the micropores of the filter body and filter cake, and may even coke directly, blocking the filter pores completely.

[0003] Furthermore, not only filtration equipment, but also pipes, valves, and other components can experience varying degrees of adhesion due to the above factors. In severe cases, pipe blockages and valve malfunctions can cause fatal problems in production and control, and even more serious safety and environmental accidents. Moreover, when the pyrolysis unit first produces pyrolysis gas, the gas volume is relatively small and the temperature is low, making it extremely easy for the dust removal system to become clogged and adhered, leading to frequent start-up and shutdown failures. Utility Model Content

[0004] To address the technical problems existing in the prior art, this utility model provides an overall preheating and start-up system for a high-temperature oily and dusty gas dust removal and filtration system for pyrolysis. This system can both preheat the dust removal and filtration system and replace coal gas as the start-up gas, thereby achieving the purpose of preheating the dust removal system before start-up and using it as the start-up gas during start-up, greatly reducing the difficulty of start-up.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is an overall preheating and start-up system for a high-temperature oily and dusty gas dust removal and filtration system for pyrolysis. It includes a pyrolysis device and a multi-stage dust removal filter connected to the pyrolysis device via a pyrolysis gas pipeline. The outlet end of the multi-stage dust removal filter is connected to a dust collector outlet pipeline. A preheating and start-up auxiliary device is connected to the multi-stage dust removal filter. This auxiliary device generates gas in the preheating section to preheat the multi-stage dust removal filter and its connecting pipelines, and provides start-up gas to the multi-stage dust removal filter in the start-up section. The preheating and start-up auxiliary device includes a high-temperature gas generation system and an input pipeline and an output pipeline connected to the multi-stage dust removal filter. The high-temperature gas generation system is connected to the input pipeline, and the circulating fan provides circulation power for the system.

[0006] Preferably, the high-temperature gas generating system includes a burner, a gas pipeline, and an air pipeline. The burner is connected to the gas pipeline and the air pipeline. The burner is also connected to a multi-stage dust removal filter through an input pipeline. An air blower is installed on the air pipeline.

[0007] Preferably, the burner is further connected to a dilution medium pipeline, and the input pipeline is connected to a first vent pipeline.

[0008] Preferably, one end of the circulating fan is connected to the output pipe, and the other end is connected to the burner through a connecting pipe. A second vent pipe is also connected to the connecting pipe.

[0009] Preferably, a temperature measuring device is installed on each of the input pipe and the output pipe, and an oxygen content sensor or a gas sampling pipe is also installed on the input pipe, the gas sampling pipe being used to sample gas to detect its oxygen content.

[0010] Compared with existing technologies, this invention has the following technical advantages: This invention can preheat the dust removal and filtration system to a temperature comparable to that of the pyrolysis gas, thus avoiding cooling of the pyrolysis gas. When the unfiltered pyrolysis gas reaches the dust removal and filtration system, it will not precipitate coal tar due to the low temperature of the dust removal and filtration system, preventing tar from adhering to coal dust and rapidly clogging the filter element. It also prevents tar gas coking and the deposition of solid coking particles in the filter cake and filter body micropores due to excessively high dust removal and filtration system temperatures, thus avoiding clogging of the filter pores. Simultaneously, by providing oxygen-deficient (oxygen content <3%) gas, it can both preheat the dust removal and filtration system and replace coal gas as the start-up gas, thereby achieving the purpose of preheating the dust removal system before operation and using it as the start-up gas, greatly reducing the difficulty of starting up. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model. Detailed Implementation

[0012] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0013] like Figure 1 As shown, a preheating and start-up system for a high-temperature oily and dusty gas dust removal and filtration system for pyrolysis includes a pyrolysis device 1 and a multi-stage dust filter 2 connected to the pyrolysis device via a pyrolysis gas pipeline. The outlet end of the multi-stage dust filter 2 is connected to a dust collector outlet pipeline 3. A preheating and start-up auxiliary device 4 is connected to the multi-stage dust filter 2. The preheating and start-up auxiliary device 4 is used to generate gas in the preheating section to preheat the multi-stage dust filter 2 and its connecting pipeline as a whole, and to provide start-up gas for the multi-stage dust filter in the start-up section.

[0014] The preheating and start-up auxiliary device 4 includes a high-temperature gas generation system 5 and an input pipe 6 and an output pipe 7 for connecting to the multi-stage dust removal filter 2. The high-temperature gas generation system 5 is connected to the input pipe 6, and the circulating fan 8 is used to provide circulating power for the system.

[0015] The high-temperature gas generation system 5 includes a burner 9, a gas pipeline 10, and an air pipeline 11. The burner 9 is connected to both the gas pipeline 10 and the air pipeline 11. The burner 9 is also connected to a multi-stage dust filter 2 via an input pipeline 6. An air blower 12 is installed on the air pipeline 11. A dilution medium pipeline 13 is also connected to the burner 9, and a first vent pipeline 14 is connected to the input pipeline 6. One end of a circulating fan 8 is connected to an output pipeline 7, and the other end is connected to the burner 9 via a connecting pipeline 15. A second vent pipeline 16 is also connected to the connecting pipeline 15. Temperature measuring devices are installed on both the input pipeline 6 and the output pipeline 7. An oxygen content sensor or a gas sampling pipeline is also installed on the input pipeline 6, which is used to sample gas to detect its oxygen content. Control valves are installed on the input pipeline 6, output pipeline 7, gas pipeline 10, air pipeline 11, dilution medium pipeline 13, first vent pipeline 14, connecting pipeline 15, and second vent pipeline 16.

[0016] This invention uses high-temperature gas generated by the high-temperature gas generation system 5 to preheat a multi-stage dust collector filter. This high-temperature gas also serves as the start-up gas for the multi-stage dust collector filter system. When the multi-stage dust collector filter is preheated and pyrolysis gas is generated by the pyrolysis device, the volume and temperature of the pyrolysis gas are initially low. If only pyrolysis gas enters the dust collector filter system at this time, blockage can still occur. To avoid this, the high-temperature gas enters the dust collector filter system together with the pyrolysis gas. Once the volume and temperature of the pyrolysis gas are normal, the preheating system is shut off via a valve. This invention avoids the adhesion and blockage of tar gas to the dust collector filter system and solves the problem of blockage caused by low-volume, low-temperature pyrolysis gas even after preheating, thus making pyrolysis start-up easier.

[0017] In practice, follow these steps: S1. Prepare high-temperature gas, close the input pipe, output pipe, and second vent pipe, open the first vent pipe, start the air blower, and adjust the flow rate of the gas pipe and air pipe to allow the gas to burn in the burner. The high-temperature gas generated in the initial stage of combustion is released through the first vent pipe on the input pipe. Open the dilution medium pipe, and detect the oxygen content and temperature of the high-temperature gas. If the oxygen content and temperature are not suitable, control the gas-air ratio and the flow rate of the dilution medium pipe by adjusting them. S2. When the oxygen content and temperature of the high-temperature gas meet the process requirements, close the first vent pipe and open the input pipe, output pipe, second vent pipe and circulating fan to allow the high-temperature gas to enter the multi-stage dust removal filter. Then, by adjusting the flow rate of the second vent pipe, part of the high-temperature gas can be discharged. S3. Gradually adjust the venting volume of the second venting pipe and reduce the medium flow rate of the dilution medium pipe so that the temperature of the high-temperature gas reaches the set requirement. S4. When the temperature of the circulating high-temperature gas reaches the preset temperature, preheating is complete; S5. Fully open the flow rate of the second vent pipe, vent all the circulating high-temperature gas, and then readjust the ratio of gas, air, and dilution medium in the pipeline to ensure that the temperature and oxygen content of the high-temperature gas are within the acceptable range. S6. Shut down the circulating fan and close the output pipeline to allow the high-temperature gas to enter the next pyrolysis process according to the established process flow. S7. Start the pyrolysis device and allow the pyrolysis gas it generates to pass through the multi-stage dust removal filter together with the high-temperature gas mentioned above. S8. Once the temperature of the pyrolysis gas reaches the normal operating temperature, shut down the high-temperature gas generation system and close the valve on the input pipeline to complete the start-up process.

[0018] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model shall be included within the scope of the present utility model.

Claims

1. A preheating and start-up system for a high-temperature oily and dusty gas dust removal and filtration system for pyrolysis, comprising a pyrolysis unit and a multi-stage dust removal filter connected to the pyrolysis unit via a pyrolysis gas pipeline, wherein the outlet end of the multi-stage dust removal filter is connected to a dust collector outlet pipeline, characterized in that: The multi-stage dust collector is connected to a preheating and start-up auxiliary device. The preheating and start-up auxiliary device is used to generate gas in the preheating section to preheat the multi-stage dust collector and its connecting pipes as a whole, and to provide start-up gas for the multi-stage dust collector in the start-up section. The preheating and start-up auxiliary device includes a circulating fan, a high-temperature gas generation system, and input and output pipes for connecting to the multi-stage dust collector. The high-temperature gas generation system is connected to the input pipe, and the circulating fan is used to provide circulation power for the system.

2. The overall preheating and start-up system of the high-temperature oily and dusty gas dust removal and filtration system for pyrolysis according to claim 1, characterized in that: The high-temperature gas generation system includes a burner, a gas pipeline, and an air pipeline. The burner is connected to the gas pipeline and the air pipeline, and the burner is also connected to a multi-stage dust removal filter through an input pipeline.

3. The overall preheating and start-up system of the high-temperature oily and dusty gas dust removal and filtration system for pyrolysis according to claim 2, characterized in that: The burner is also connected to a dilution medium pipeline, and the input pipeline is connected to a first venting pipeline.

4. The overall preheating and start-up system of the high-temperature oily and dusty gas dust removal and filtration system for pyrolysis according to claim 2, characterized in that: One end of the circulating fan is connected to the output pipe, and the other end is connected to the burner through a connecting pipe. A second vent pipe is also connected to the connecting pipe.

5. The overall preheating and start-up system of a high-temperature oily and dusty gas dust removal and filtration system for pyrolysis according to any one of claims 1-4, characterized in that: Temperature measuring devices are installed on both the input and output pipes. An oxygen content sensor or a gas sampling pipe is also installed on the input pipe. The gas sampling pipe is used to sample gas to detect its oxygen content.

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