Preparation method of composite absorber for removing carbon dioxide from flue gas

Abstract

The invention provides a preparation method of a composite absorber for removing CO2 from flue gas, wherein, the CO2 absorbent comprises the following components in mass percent: 50-75% of CaO, 10-35% of Al2O3 and 10-25% of MgO. The preparation method comprises the following steps: mixing soluble calcium, aluminium and magnesium salt solution with carbonate precipitant solution, adding a dispersant to the mixed solution, washing, drying and shaping the formed coprecipitate product, and calcining at the temperature of 850 DEG C in the air atmosphere for 1-2 hours. The CO2 absorbent can be used for removing CO2 from the flue gas under atmospheric pressure or pressurized conditions. Compared with the conventional absorbents, the CO2 composite absorber of the invention greatly improves the cyclic carbonating performance, the mechanical strength and the anti-sintering capacity in the process of cyclically capturing CO2, and keeps higher CO2 capture rate in the cyclic calcining / carbonating reaction processes, thereby reducing the consumption dose in the CO2 removing process and improving the economical efficiency of the process.

Description

technical field [0001] The invention provides a CO2 containing alumina and magnesia, with calcium oxide as the main component, which has anti-wear and anti-sintering functions. 2 Composite absorbent and preparation method thereof, used for removing CO in flue gas 2 craft. The invention belongs to the technical field of environmental pollution prevention and clean coal combustion. Background technique [0002] The climate warming in the past 50 years is mainly caused by CO 2 caused by the warming effect of greenhouse gases. Global warming has led to a series of climate anomalies and natural disasters, such as sea level rise and land inundation, shifting of climate zones, intensification of hurricanes, vegetation migration and species extinction, and epidemics of plague. The impact on humans and the environment has been Beyond people's imagination, it will threaten the survival and development of human beings more and more seriously. [0003] Recently, my country's CO 2 ...

AI Technical Summary

Problems solved by technology

However, studies have shown that limestone and other CO 2 Absorbents have a serious problem: with the increase of the number of cyclic calcination / carbonation reactions, the sintering effect causes the carbonation conversion rate of the absorbent to drop rapidly. After about 10 cycles of reactions under normal pressure, the carbonation conversion rate drops to 30% or less

At the same time, the easy pulverization of limestone makes it very easy to break and precipitate out of the furnace during the cyclic reaction process. The consumption of absorbent is large, and such a large amount of precipitation will also cause problems such as wear and dust accumulation in the tail flue.

In order to maintain high CO 2 In order to reduce the removal efficiency, the addition of fresh absorbent has to be increased, which not only increases the cost, but also aggravates the wear of the heating surface in the furnace, which will threaten the safety and economic operation of the equipment

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