Valorização energética de lodo biológico da indústria de polpa celulósica através da briquetagem

• Ano de defesa: 2010
• Autor(a) principal: Rodrigues, Valéria Antônia Justino
• Orientador(a): Silva, Cláudio Mudado
• Banca de defesa: Mounteer, Ann Honor , Rezende, Ana Augusta Passos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Ciência Florestal
• Departamento: Manejo Florestal; Meio Ambiente e Conservação da Natureza; Silvicultura; Tecnologia e Utilização de
• País: BR
• Palavras-chave em Português: Energia; Biomassa; Lodo biológico; Briquetagem
• Palavras-chave em Inglês: Energy; Biomass; Biological sludge; Briquetting
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::RECURSOS FLORESTAIS E ENGENHARIA FLORESTAL::TECNOLOGIA E UTILIZACAO DE PRODUTOS FLORESTAIS
• Link de acesso: http://locus.ufv.br/handle/123456789/3043

The industry to bleached Kraft pulp need, in their production processes of high energy demand. Much of this energy is generated in the chemical recovery boiler and, the other part in the biomass boiler, with the reuse of black liquor and of the wood residues, respectively. However, other residues are generated and disposed of in landfills without proper reuse. Among the waste, the biological sludge has great potential energy, because it is rich in organic material. Thus, this search objective was study the feasibility of reusing the biological sludge together with fine wood as raw material in the fabrication of briquettes for energy generation. The fine wood were used to improve product features, since it has lignin and lower ash content, besides presenting low concentrations of sulfur and nitrogen. The biological sludge was mixed with fine wood in proportions of 0, 20, 40, 60, 80 and 100 %. It was used a pressure of 68,9 x 105 N m-2 for waste compaction for five minutes and cooling time of ten minutes. The temperature analysis (90 and 120 ° C) was determined according to the range of lignin plasticization. The briquettes were made in two phases, the first, in a briquetter of the laboratory and the second phase in a industrial briquette. For to understand the energy behavior of briquettes were assessed the gross calorific value, the ash content, the elemental composition, the volatile materials, the fixed carbon and calorimetric analysis. Besides these features, were also studied apparent density, compressive strength and hygroscopic equilibrium moisture which are important parameters to evaluate the stability of the briquette when subjected to conditions of transport and storage. To study the environmental effects of combustion these wastes at the mill were evaluated the emission of air pollutants, as well as the dangerousness of the ash and of the wastes. The biological sludge, fine wood and ash were classified as residue Class II A. The biological sludge has a gross calorific value similar to other waste used for making briquettes, but high content ash. The combination of fine wood with the sludge decreased the ash content, in addition the content nitrogen and sulfur. The combustion with sludge 20 % not presented emissions of pollutants in disconformity of the legislation for boilers with nominal power over 70 MW. The biological sludge improved the compressive strength, the apparent density and hygroscopicity of briquettes made with fine wood. The percentage of ideal mixing was with sludge 60 % for all parameters evaluated. The reuse of sludge in the briquetting process was highly feasible, because besides reducing the environmental impacts arising from their improper disposal, presents a way of disposal with high value-added to the residue. After the study, it was found that the biological sludge should not be considered as residue but as raw material with high potential for exploitation in the combustion process for power generation.