Absorção de CO2 em solução de NaOH em uma torre de nebulização
Data
2021-02-24
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
A poluição do ar e o aumento da emissão de CO2 é tema de preocupação mundial,
pois as emissões desse poluente além de poder influenciar no aumento da
temperatura ambiente, por ação do efeito estufa, também pode ocasionar
problemas respiratórios, mortes e grande impacto ambiental. Para mitigar esse
problema no âmbito das plantas industriais, foram estudados e desenvolvidos
equipamentos que atuam no controle do dióxido de carbono e dentre esses
destaca-se a torre de nebulização. O presente trabalho estudou a transferência de
massa para absorção de CO2 em uma torre de nebulização que foi anteriormente
projetada para a remoção de dióxido de enxofre, analisando assim o 𝐾ga,
coeficiente volumétrico de transferência de massa e a eficiência de remoção do
dióxido de carbono. Para atingir esse objetivo foi utilizada uma bancada
experimental contendo uma torre de nebulização de 600mm de altura com
circulação de NaOH na fase líquida que possuía vazões predeterminadas de 300 e
500L/h juntamente com um gás contaminado de CO2 em 1000ppm com vazões que
variaram de 12 a 34m3/h. A eficiência de remoção do dióxido de carbono nesta torre
variou de 8,33% a 40% dependendo das variáveis do processo, enquanto o 𝐾𝑎
variou 8,48.10-4 a 1,78. 10-4Kg/(s.m3.atm). Os resultados obtidos indicaram que a
baixa eficiência de 40% dessa coluna em comparação aos dados literários de 90%,
pode estar correlacionado ao tamanho da coluna em 600mm, sugerindo a
continuação deste estudo com colunas maiores.
Air pollution and the increasing of CO2 emissions are a matter of global concern, as emissions of this pollutant, in addition to being able to influence the increase in ambient temperature, due to the greenhouse effect, can also cause respiratory problems, deaths and great environmental impact. To mitigate this problem in the context of industrial plants, equipment that works to control carbon dioxide has been studied and developed, and among these, the spray tower stands out. The present work studies the mass transfer for CO2 absorption in a spray tower that was previously designed for the removal of sulfur dioxide, thus analyzing the 𝐾𝑎, volumetric mass transfer coefficient and the carbon dioxide removal efficiency. To achieve this objective, an experimental bench was used containing a 600mm high nebulization tower with circulation of NaOH in the liquid phase, which had predetermined flow rates of 300 and 500L / h together with a contaminated CO2 gas at 1000ppm with flow rates that varies from 12 to 34m3 /h. The efficiency of carbon dioxide removal in this tower ranged from 8.33% to 40% depending on the process variables, while Kga ranged from 8.48.10-4 to 1.78. 10-4Kg/(s.m3 .atm). The results obtained indicated that the low efficiency of 40% of this column compared to literary data of 90%, can be correlated to the column size in 600mm, suggesting the continuation of this study with larger columns.
Air pollution and the increasing of CO2 emissions are a matter of global concern, as emissions of this pollutant, in addition to being able to influence the increase in ambient temperature, due to the greenhouse effect, can also cause respiratory problems, deaths and great environmental impact. To mitigate this problem in the context of industrial plants, equipment that works to control carbon dioxide has been studied and developed, and among these, the spray tower stands out. The present work studies the mass transfer for CO2 absorption in a spray tower that was previously designed for the removal of sulfur dioxide, thus analyzing the 𝐾𝑎, volumetric mass transfer coefficient and the carbon dioxide removal efficiency. To achieve this objective, an experimental bench was used containing a 600mm high nebulization tower with circulation of NaOH in the liquid phase, which had predetermined flow rates of 300 and 500L / h together with a contaminated CO2 gas at 1000ppm with flow rates that varies from 12 to 34m3 /h. The efficiency of carbon dioxide removal in this tower ranged from 8.33% to 40% depending on the process variables, while Kga ranged from 8.48.10-4 to 1.78. 10-4Kg/(s.m3 .atm). The results obtained indicated that the low efficiency of 40% of this column compared to literary data of 90%, can be correlated to the column size in 600mm, suggesting the continuation of this study with larger columns.