Method for separating and purifying lime kiln tail gas

Abstract

The invention provides a method for separating and purifying lime kiln tail gas. The method comprises the following steps: (1) introducing the tail gas discharged from a lime kiln into a washing tower to be sprinkled, introducing the sprinkled tail gas into a desulphurization tower, and performing the desulphurization treatment; (2) introducing the desulphurized tail gas into an MEA absorption tower, allowing a monoethanolamine solution in the MEA absorption tower to absorb carbon dioxide in the tail gas, sending the monoethanolamine solution absorbing the carbon dioxide into a parsing tower, performing the volume expansion and decompression, and then releasing the carbon dioxide; (3) pressurizing, dehydrating and filtering the released carbon dioxide, and then introducing the carbon dioxide into a purification absorption tower to remove impurities; and (4) discharging the tail gas from the MEA absorption tower, pressurizing, dehydrating and filtering the tail gas, then introducing the tail gas into the purification absorption tower to remove impurities, and obtaining nitrogen. By adopting the method for separating and purifying the lime kiln tail gas, the waste gas can be converted into treasure. Not only is the requirement on the national industrial structural adjustment and environmental protection policies met, but also certain economic benefit can be brought to the enterprises.

Description

technical field [0001] The invention belongs to the field of chemical industry, and in particular relates to a method for separating and purifying lime kiln tail gas. Background technique [0002] The main raw materials of the electric arc calcium carbide production process include coke and lime, among which lime is obtained by calcining limestone in a lime kiln. A large amount of lime kiln tail gas will be produced during the lime kiln calcining process, and the lime kiln tail gas contains 28-35% of CO 2 Gas, traditional process waste gas is directly discharged into the atmosphere after dust removal reaches the standard, causing serious pollution. In order to achieve the goal of low-carbon emissions in industrialization, the country clearly put forward carbon emission control indicators in the "Government Work Report" and "Thirteenth Five-Year Plan", and established carbon emission exchanges one after another to encourage enterprises to adopt energy-saving and emission-red...

AI Technical Summary

Problems solved by technology

[0002] The main raw materials of the electric arc calcium carbide production process include coke and lime, among which lime is obtained by calcining limestone in a lime kiln. A large amount of lime kiln tail gas will be produced during the lime kiln calcining process, and the lime kiln tail gas contains 28-35% of CO 2 Gas, traditional process waste gas is directly discharged into the atmosphere after dust removal reaches the standard, causing serious pollution

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