CN-122015511-A - Gangue ceramsite roasting smoke and wind circulation system for cooling high-temperature ceramsite through hot air circulation

Abstract

The embodiment of the invention provides a coal gangue ceramsite roasting smoke and wind circulation system for cooling high-temperature ceramsite through hot air circulation, and relates to the technical field of roasting hot air circulation utilization. The invention introduces low-temperature flue gas with the raw material calorific value of 300-1000kcal/kg into a high-temperature cooling section, wherein the low-temperature flue gas with the raw material calorific value of 200-400 ℃ and the oxygen content of 15-19% is discharged from a preheating section, and is used for cooling 1120-1200 ℃ of high-temperature ceramsite in the high-temperature cooling section, the low-temperature flue gas is heated to form 850-1000 ℃ high-temperature flue gas after absorbing sensible heat under the condition of 400-1000Nm 3 /t of flue gas flow and is recycled to a roasting section, a soaking section or a waste heat boiler, a complete hot air closed loop circulation system with the low-temperature flue gas cooling ceramsite-heating being high-temperature combustion supporting air-circulation recycling is constructed, the energy waste caused by direct discharge of the low-temperature flue gas is avoided, the overall heat efficiency of the system is obviously improved, and simultaneously, the stability of the subsequent waste heat utilization and other processes is improved by flowing the flue gas through a material layer.

Inventors

• LI YU
• HE XUHAN
• ZHANG XIAOQIANG
• LI QINGYI
• WU PINGAN
• GUAN HAO
• Ling Qianghua
• WU JIAN
• WANG CHUNBO
• SUN LIFENG
• ZENG LINGDONG
• WEI CHAOHUI

Assignees

• 中能建装配式建筑产业发展有限公司
• 中能建科锐技术(大同)有限公司
• 北京科技大学

Dates

Publication Date

20260512

Application Date

20260302

Claims (7)

1. 1. The coal gangue ceramsite roasting smoke air circulation system for cooling high-temperature ceramsite through hot air circulation is characterized by comprising a roasting device and/or a waste heat utilization boiler, wherein the roasting device comprises a preheating section, a roasting section, a soaking section and a high-temperature cooling section which are sequentially communicated; The preheating section is communicated with the high-temperature cooling section through a flue gas pipeline; The high-temperature cooling section is communicated with the roasting section and/or the soaking section through a flue gas pipeline, and/or the high-temperature cooling section is communicated with the waste heat utilization boiler through a flue gas pipeline; Wherein, the heat value of the raw pellets of the used coal gangue ceramsite raw materials is 300-1000kcal/kg; the raw pellets of the gangue ceramsite raw materials undergo internal combustion decarburization reaction in a preheating section, and low-temperature flue gas with the temperature of 200-400 ℃ and the oxygen content of 15-19% is discharged; the low-temperature flue gas is led into a high-temperature cooling section for cooling high-temperature ceramsite with the temperature of 1120-1200 ℃ in the high-temperature cooling section; The volume flow of the low-temperature flue gas entering the high-temperature cooling section is controlled to be 400-1000Nm 3 per ton of high-temperature ceramsite, so that the low-temperature flue gas absorbs heat and heats up after heat exchange with the high-temperature ceramsite to form high-temperature flue gas with the temperature of 850-1000 ℃; The high-temperature flue gas is circularly conveyed to a roasting section and/or a soaking section to be used as combustion-supporting air for recycling, and/or the high-temperature flue gas is conveyed to a waste heat utilization boiler to be subjected to heat exchange.
2. 2. The coal gangue ceramsite roasting smoke and wind circulation system for cooling high-temperature ceramsite through hot air circulation according to claim 1, wherein the roasting device further comprises a hot air drying section, and the hot air drying section is communicated with the preheating section through a pipeline and is used for drying raw pellets of a coal gangue ceramsite raw material and then conveying the dried raw pellets to the preheating section.
3. 3. The coal gangue ceramsite roasting smoke air circulation system for cooling high-temperature ceramsite by hot air circulation according to claim 1, wherein the roasting device further comprises a middle-low temperature cooling section, and the middle-low temperature cooling section is communicated with the high-temperature cooling section through a pipeline and is used for conveying the high-temperature ceramsite cooled by high-temperature cooling Duan Zhongleng to the middle-low temperature cooling section for secondary cooling.
4. 4. The coal gangue ceramsite roasting smoke and wind circulation system for cooling high-temperature ceramsite by hot air circulation according to claim 1, wherein the outlet temperature of the high-temperature ceramsite cooled by high-temperature cooling Duan Zhongleng is 600-800 ℃.
5. 5. The system for circulating flue gas generated by roasting the gangue ceramsite with the high-temperature ceramsite cooled by hot air circulation according to claim 1, wherein the waste heat utilization boiler is further communicated with the preheating section through a flue gas pipeline and is used for returning the high-temperature flue gas subjected to heat exchange in the waste heat utilization boiler to the preheating section for recycling.
6. 6. The system for circulating flue gas generated by roasting gangue ceramsite with high-temperature ceramsite cooled by hot air circulation according to claim 1, wherein a flue gas pipeline between the preheating section and the high-temperature cooling section is also communicated with an air pipeline, and is used for inputting ambient air to control the oxygen content of the low-temperature flue gas within a range of 15-19%.
7. 7. The coal gangue ceramsite roasting smoke and wind circulation system for hot air circulation cooling high-temperature ceramsite according to claim 1, wherein the raw material green pellets of the coal gangue ceramsite comprise coal gangue, gasified slag, coal slime or oil shale.

Description

Gangue ceramsite roasting smoke and wind circulation system for cooling high-temperature ceramsite through hot air circulation Technical Field The invention relates to the technical field of roasting hot air circulation utilization, in particular to a coal gangue ceramsite roasting smoke air circulation system for cooling high-temperature ceramsite through hot air circulation. Background The gangue ceramsite is a lightweight aggregate prepared by using gangue as a main raw material and through the procedures of balling, roasting and the like, and is widely applied to the fields of construction, environmental protection, chemical industry and the like. In the prior industrial practice, the gangue ceramsite is generally continuously produced by adopting equipment such as a belt roasting machine, a tunnel kiln or a sintering machine. In the roasting process of the high-heat-value coal gangue, a large amount of low-temperature low-quality smoke is discharged in the preheating section due to the internal combustion decarburization reaction. However, conventional roasting systems generally lack an efficient utilization path for the low temperature low quality flue gas. Because the temperature is low, the system is difficult to be used for power generation or efficient waste heat recovery, and most of the existing systems directly exhaust the system into the atmosphere, so that a large amount of low-grade heat energy is wasted. At the same time, the temperature of the ceramsite exiting the soaking section is typically up to 1100 ℃ or more, and must be cooled for subsequent transportation, screening and storage. The main current cooling mode is to adopt ambient air to perform forced convection cooling on the high-temperature ceramsite. But is limited by low initial temperature of air and limited heat capacity, the energy level of the obtained hot air is not high, and the internal structure of the ceramsite is different due to uneven distribution of cooling intensity, so that the consistency of the performance of the product is affected. In addition, in existing firing systems, the flue gas emissions and ceramsite cooling typically operate as two separate units, lacking energy synergy with each other. The low-temperature flue gas is not effectively utilized, and cold air is additionally introduced in the cooling process, so that not only is the energy consumption of a fan increased, but also the overall thermal efficiency of the system is difficult to further improve. Disclosure of Invention In order to solve the technical problems that low-temperature flue gas generated in the ceramsite roasting process is not effectively utilized and is directly discharged to cause heat energy waste, and meanwhile, environmental cold air is additionally introduced into ceramsite cooling to cause lower overall heat efficiency of the system, the embodiment of the invention provides a coal gangue ceramsite roasting flue gas and air circulation system for cooling high-temperature ceramsites through hot air circulation. The technical scheme is as follows: The invention provides a coal gangue ceramsite roasting smoke and wind circulation system for cooling high-temperature ceramsite by hot air circulation, which comprises a roasting device and/or a waste heat utilization boiler, wherein the roasting device comprises a preheating section, a roasting section, a soaking section and a high-temperature cooling section which are sequentially communicated; The preheating section is communicated with the high-temperature cooling section through a flue gas pipeline; The high-temperature cooling section is communicated with the roasting section and/or the soaking section through a flue gas pipeline, and/or the high-temperature cooling section is communicated with the waste heat utilization boiler through a flue gas pipeline; Wherein, the heat value of the raw pellets of the used coal gangue ceramsite raw materials is 300-1000kcal/kg; the raw pellets of the gangue ceramsite raw materials undergo internal combustion decarburization reaction in a preheating section, and low-temperature flue gas with the temperature of 200-400 ℃ and the oxygen content of 15-19% is discharged; the low-temperature flue gas is led into a high-temperature cooling section for cooling high-temperature ceramsite with the temperature of 1120-1200 ℃ in the high-temperature cooling section; The volume flow of the low-temperature flue gas entering the high-temperature cooling section is controlled to be 400-1000Nm 3 per ton of high-temperature ceramsite, so that the low-temperature flue gas absorbs heat and heats up after heat exchange with the high-temperature ceramsite to form high-temperature flue gas with the temperature of 850-1000 ℃; the high-temperature flue gas is circularly conveyed to a roasting section and/or a soaking section to be used as combustion-supporting air for recycling, and/or the high-temperature flue gas is conveyed to a waste heat boiler to be subjected