Novo método para determinação da quantidade de recirculação de cinzas nas caldeiras de recuperação

• Ano de defesa: 2013
• Autor(a) principal: Guimarães, Matheus Antunes
• Orientador(a): Cardoso, Marcelo
• Banca de defesa: Saturnino, Daniel Moreira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado Profissionalizante em Tecnologia de Celulose e Papel
• Departamento: Qualidade da madeira; Tecnologia de celulose e papel
• País: BR
• Palavras-chave em Português: Resíduos industrias - Reaproveitamento; Caldeiras
• Palavras-chave em Inglês: Waste industries - Reuse; Boilers
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::TECNOLOGIA E UTILIZACAO DE PRODUTOS FLORESTAIS::TECNOLOGIA DE CELULOSE E PAPEL
• Link de acesso: http://locus.ufv.br/handle/123456789/5942

In kraft recovery boiler operation, fly ash or dust generated from black liquor combustion is mixed with the virgin black liquor in a mix tank and returned to the boiler with the as-fired black liquor. This internal recycled dust stream varies widely from boiler to boiler and from time to time, and can have a great impact on the as-fired black liquor flow and properties, and ultimately on the boiler thermal performance. A new method has been developed which can be used to quickly and accurately determine the amount of internal recycled dust in recovery boilers. It is based on the difference between the total organic carbon content (or heating value) of the virgin black liquor and that of the as-fired black liquor. Tests using the method were performed on recovery boilers at three of Fibria s mills in Brazil. The results show that while the specific virgin black liquor solids produced at these mills were about the same, the internal recycled dust load varied widely from as low as 5,6 wt% of as-fired black liquor solids fired in the boiler at one mill to as high as 12,7 wt% at another mill. A qualitative analysis showed that the sulphidity of the liquor and the velocity and flow of the gases inside the furnace might in part justify the observed differences.