Ozone Bleaching
Mostrando 1-7 de 7 artigos, teses e dissertações.
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1. UM NOVO CONCEITO DE BRANQUEAMENTO DE POLPA KRAFT DE EUCALIPTO COM OZÔNIO EM MÉDIA CONSISTÊNCIA
The effect of hot acid hydrolysis (A-stage) pretreatment on the ozone (Z/E) performance at medium consistency was evaluated. An experimental plan was set up involving full optimization of A and Z/E stages for an oxygen delignified eucalypt kraft pulp. A-stage caused significant kappa and HexA drop, and the optimum condition for this stage being pH 3.0, 90 º
Quím. Nova. Publicado em: 2017-01
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2. Low environmental impact bleaching sequences for attaining high brightness level with eucalyptus SPP pulp
The alternatives used for minimizing the usage of chlorine dioxide in bleaching sequences included a hot acid hydrolysis (Ahot) stage, the use of hot chlorine dioxide (Dhot) and ozone stages at medium consistency and high consistency (Zmc and Zhc), in addition to stages with atmospheric hydrogen peroxide (P) and pressurized hydrogen peroxide (PO). The result
Brazilian Journal of Chemical Engineering. Publicado em: 2009-03
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3. Treatment of pulp and paper bleaching effluents by means of ozone advanced oxidation processes / Tratamento de efluentes do branqueamento da polpa celulósica por processos oxidativos avançados baseados em ozônio
The impact of ozone oxidation in transforming high molecular weight (HMW) organic compounds in order to improve the biodegradability of pulp and paper effluents was investigated under different ozone doses. The experiments were conducted uppon a primary treated effluent and an alkaline bleach plant effluent taken from two pulp mills. The effluents were inves
Publicado em: 2008
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4. Uso de ozônio como pré e pós-tratamento de efluentes da indústria de celulose kraft branqueada / Pre and post ozone treatment of bleached kraft pulp mill effluents
This work evaluated the combination of ozone and activated sludge for treatment of bleached kraft pulp effluents. Ozonation was done before and after biological treatment. First the influence of pH, temperature and hydrogen peroxide dose on ozonation was assessed in order to optimize treatment efficiency, which was evaluated in terms of COD, BOD5, lignin, bi
Publicado em: 2006
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5. Identificação de constituintes químicos potencialmente envolvidos na reversão de alvura de polpa Kraft branqueada pelas seqüências OZDHT (PO)D e OZ/EDP / Chemical representatives identification potentially involved in the reversion of whiteness of pulp kraft whitened by the sequences OZDHT(PO)D and OZIEDP
The pulp and paper section significantly contributes to the Brazilian economy. The industries produces million of tons of pulp yearly, yielding superavit of billion of dollars in the section of paper and pulp. The quality of Kraft cellulose commercialized in the international marked is evaluated, mainly because of its physical properties, anatomical characte
Publicado em: 2005
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6. Modo de ação de xilanases de Aspergillus sp 2M1 em sequencias de branqueamento de polpas de Eucalyptus grandis totalmente livres de cloro
Unbleached Eucalyptus grandis kraft pulps were submitted to TCF bleaching sequences (XOP - Xylanase/Oxygen/Peroxide and XZP -Xylanase/Ozone/Peroxide) using a non-commercial enzyme (Asperzyme 2M1) at the X stage. During the enzymatic treatment, the xylanase charge, inducted carbon source, incubation temperature and incubation time were changed. The pulp sampl
Publicado em: 1999
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7. Xilanases de aspergillus SP 2M1 : produção, caracterização e aplicação no branqueamento de polpas kraft
This study deals with the optimization for Aspergillus sp 2M1 growth and its xylanase production. Besides these aspects, some of lhe xylanase properties looking for an application in a bleaching Eucalyptus Kraft pulp were also studied. The optimal fungal growth conditions and enzyme production, in solid as in liquid media were following: Birchwood xylan as c
Publicado em: 1995