Device and method for reducing oxygen content of coal slime drying hot air in gas oxidation furnace

Abstract

The invention relates to a device and a method for reducing oxygen content of coal slime drying hot air in a gas oxidation furnace. The technical scheme is that the device comprises a gas oxidation system and a drying hot air oxygen content control system, wherein a gas pipeline is connected with an inlet of an air blower; an outlet of the air blower is connected with an inlet of a reversing valveand the gas oxidation furnace in sequence; an outlet of the reversing valve is connected with a chimney of the oxidation furnace; two ends of a backflow pipeline are connected to the gas pipeline andthe chimney of the oxidation furnace; and an oxygen content adjusting valve is arranged in the middle of the backflow pipeline. The device and the method have the beneficial effects that the popularization and adaptation range is expanded; by recycling oxidation flue of the device, the oxygen content of the drying hot air is reduced and is adjustable according to an actual situation; the construction and operation of a project are not affected even if an available resource condition for reducing oxygen by blending inert gas does not exist on site; the heat utilization rate of the oxidation furnace is high; about 15 percent of low-temperature flue at about 85 DEG C in the oxidation furnace is refluxed for utilizing, the gas oxidation heat is further utilized; and therefore, the device is more economic and reasonable compared with the original technology by arranging a low-temperature flue heat regenerator.

Description

technical field [0001] The invention relates to a coal mine gas and coal slime utilization technology, in particular to a device and method for reducing the oxygen content of hot air for drying coal slime in a gas oxidation furnace. Background technique [0002] Coal mine gas oxidation technology has been basically mature after more than ten years of research and on-site industrial application. According to the "Safety Requirements for Engineering Application of Type Oxidation Device" standard, more than 20 projects have been built and operated in the country. The oxidation of coal mine gas has been recognized by the society, which has played a positive and far-reaching impact on the energy saving and emission reduction of the coal industry and the protection of the atmospheric environment. China's 70 More than 100% of the coal can be sold and used after washing. Coal washing produces a large amount of coal slime. The coal-fired hot air stove was originally used to dry the c...

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Problems solved by technology

[0003] In 2015, a hot air drying coal slime project was built in the Dingji Coal Mine of Huainan Mining Group, Anhui Province, which used the high-temperature oxidation flue gas of the gas oxidation furnace at about 950°C and the tail gas of the gas internal combustion engine generator set at about 500°C to mix to about 700°C. The oxygen content of the generator set tail gas is less than 7%, and the oxygen content after mixing with the gas oxidation furnace flue gas with an oxidation content of about 19% is controlled below 14%, so as to ensure that there will be no deflagration accidents in the tumble dryer. This project It is based on the fact that the mine has sufficient exhaust gas mixed with gas internal combustion generators, and the oxygen content of the hot air used to dry the slime can be controlled within a safe range. In reality, there are very few coal mines with such conditions, and the drying is controlled by other means. The oxygen content of coal slime hot air (such as nitrogen blending, etc.) is not economically cost-effective. Under the current technical conditions, it is difficult to apply gas oxidation furnace to coal slime drying technology. Therefore, it is necessary to find a safe and reliable , cost-effective method, it is very necessary to use gas oxidation furnace to dry coal slime

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