Flue gas cleaning treatment method during producing carbon product

Abstract

The invention relates to a flue gas purifying treatment method during the production process of carbon products. The flue gas purifying treatment method is characterized in that the treatment process directly sends flue gas produced in the production process of a green electrode into a calcining furnace for high-temperature calcination, high-temperature gas after the calcination is mixed with low-temperature gas emitted from a roasting furnace, the mixed calcination is carried out under the high temperature via sufficient calorific value thereof or with the help of a combustion adjuvant, the high-temperature gas emitted after the calcination is taken as a heat source to be directly sent to a boiler, the gas emitted from the boiler is finally subjected to desulphurization and defluorination treatment, then a part of the purified gas is returned to the production process of the green electrode, a pipeline is heated and subjected to the temperature keeping during the process of sending the dust collecting flue gas produced during the process to the calcining furnace, and the residual purified gas is subjected to the high-altitude emission. The method of the invention can thoroughly treat the harmful substances in the flue gas and comprehensively take into account the actual production conditions and the heat of the emitted flue gas of various work segments, the process flow is simple, the operation is convenient and the treatment cost is low.

Description

technical field [0001] The invention relates to a flue gas purification treatment method in the production process of carbon products. Background technique [0002] Primary aluminum is produced using the Hall-Heroult electrolysis process. The carbon electrodes (including cathode and anode) used in this process are made of calcined petroleum coke, anthracite and other carbonaceous aggregates and coal tar pitch through kneading, molding and high-temperature roasting. During the production process, a large amount of flue gas will be produced, including carbon dust, asphalt smoke, tar, SO 2 , fluorine-containing gases, etc. These substances not only pollute the environment, but also cause great harm to the health of humans, animals and plants, especially the 3,4-benzopyrene contained in asphalt smoke has carcinogenic effect, so the purification of flue gas Governance is essential. [0003] In the production process of carbon electrodes, there are three main process steps to p...

AI Technical Summary

Problems solved by technology

First of all, the flue gas generated during the raw material calcination process has not been dealt with by corresponding measures

Secondly, the flue gas generated during the production of raw electrodes is generally treated by adsorption method, and the exhaust gas still contains some carbon dust and asphalt fume. Moreover, the adsorption method is complicated in process, high in cost, and difficult to handle with adsorbents.

In addition to the adsorption method (including carbon powder adsorption method and alumina adsorption method), the roasting flue gas treatment methods include wet washing, electrostatic capture method and simple incineration method. The adsorption method used here also faces complex processes, high costs, and adsorption It is difficult to deal with the solvent; the electrostatic capture method is difficult to clean up, and there is a danger of explosion and combustion in the equipment; the secondary pollution of water by wet treatment is difficult to deal with, and these methods cannot effectively treat various components in the flue gas at the same time. The most important thing is that the carcinogen 3,4-benzopyrene in the asphalt smoke cannot be processed; and the simple incineration method needs to consume a large amount of fuel, and the process cost is very high

Moreover, the existing methods only deal with a certain process link separately, lack effective comprehensive consideration, and cannot realize the comprehensive utilization of combustible substances in the flue gas

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