Dedusting and dehumidifying method for air with freezing method and equipment thereof

Abstract

The invention relates to a dedusting and dehumidifying method and equipment thereof for furnace top coal gas of a blast furnace, a converter or a COREX furnace. The method comprises the steps of precooling, self-circulation cooling, re-cooling, demisting and self-circulation heating and rewarming. The equipment comprises a stream guide plate, a precooler, a self-circulation cooler, a first water discharge section, a cooler, a second water discharge section, a demister, a rewarming heater and an outlet stream guide plate which are sequentially arranged between a gas inlet and a gas outlet in a shell. The method and the equipment are used to reduce the emission of dust and the pollution to the air. The heat of gas at the inlet and the cold output of gas at the outlet are recycled so as to repeatedly utilize energy sources and save the energy source consumption; the relative humidity of coal gas treated by the method and the equipment is reduced, thereby the occurrence of condensed water in the process of pipeline conveying is reduced, the corrosion action to the pipeline is reduced and the safety is improved; in addition, the reduction of the relative humidity of the coal gas improves the thermal value of the coal gas.

Description

technical field [0001] The present invention relates to a dust-removing and dehumidifying method and equipment for gas containing dust and moisture, in particular to a method and equipment for dedusting and dehumidifying gas at the top of a smelting blast furnace, converter or COREX furnace. Background technique [0002] Blast furnaces, converters or COREX furnaces used for ironmaking or steelmaking will produce a large amount of gas during smelting. Converter gas (LDG), blast furnace gas (BFG) and Corex furnace gas (CrG) contain reusable combustible gases ——In addition to gas, it also contains a large amount of water vapor and dust, and the dust content and moisture content are relatively high. If it is to be recycled, it needs to be dedusted and dehumidified. The traditional method is to use wet dust removal (annular seam washing system, double venturi washing system, etc.), and use atomized water droplets to capture dust particles in the gas. After wet dust removal, the h...

AI Technical Summary

Problems solved by technology

The traditional method is to use wet dust removal (annular seam washing system, double venturi washing system, etc.), and use atomized water droplets to capture dust particles in the gas. After wet dust removal, the humidity and dust content of the clean gas will drop significantly. For example, the temperature of the net converter gas is about 70°C, and the dust content is 70-200mg / Nm 3 , the relative humidity is 100%, such gas is directly discharged into the atmosphere or discharged into the atmosphere after being burned, and the dust contained in it will form respirable dust, which will increase the concentration of respirable dust in the atmosphere, causing air pollution and affecting the human body health

In addition, due to the high relative humidity of the gas after wet dedusting, a large amount of condensed water will be generated during pipeline transportation, which will corrode the pipeline and cause safety hazards

Images