An Eco-Friendly Approach: Incorporating a Xylanase Stage at Various Places in ECF and Chlorine-based Bleaching of Eucalyptus Pulp
A potentially more environmentally compatible approach was evaluated, involving the use of an enzyme (X) stage optimally inserted into various bleaching sequences for Eucalyptus kraft pulps. The efficacy of the X stage was evaluated in terms of final brightness, CIE whiteness, post-color number (bri...
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| Format: | Article |
| Language: | English |
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North Carolina State University
2016-05-01
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| Series: | BioResources |
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| Online Access: | http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_11_2_5381_Gangwar_Eco_Friendly_Approach_Xylanase_Stage |
| _version_ | 1819205075924418560 |
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| author | Avdhesh K. Gangwar N. Tejo Prakash Ranjana Prakash |
| author_facet | Avdhesh K. Gangwar N. Tejo Prakash Ranjana Prakash |
| author_sort | Avdhesh K. Gangwar |
| collection | DOAJ |
| description | A potentially more environmentally compatible approach was evaluated, involving the use of an enzyme (X) stage optimally inserted into various bleaching sequences for Eucalyptus kraft pulps. The efficacy of the X stage was evaluated in terms of final brightness, CIE whiteness, post-color number (brightness reversion), effluent characteristics, etc. The results showed considerable benefits with an enzymatic pre-treatment bleaching sequence for improved final pulp brightness (1.6 units higher) and reduced adsorbable organic halogens (AOX) (32% lower), in addition to improved biological oxygen demand (BOD) to chemical oxygen demand (COD) ratio, when using 0.5 kg/t pulp dosage of xylanase; enzymatic post-treatment bleaching sequences were observed to boost final CIE whiteness up to 3.4 units and to reduce post color number by 48% at 0.5 kg/t pulp dosage of xylanase. In addition, approximately 32% reductions in AOX released, as well as appreciable improvement in BOD-to-COD ratio, were observed in the bleach effluents. An improved ratio of BOD-to-COD facilitates possible enhancement in the bio-degradability of discharge effluents in a secondary treatment stage. Nine different bleaching sequences were compared. Three sequences for each category (pre-treatment, intermediate, and post-treatment bleaching sequences) were performed to provide an overview of the influence of xylanase treatment on various pulp properties and environmental sum parameters of the ensuing effluents. |
| first_indexed | 2024-12-23T04:45:57Z |
| format | Article |
| id | doaj.art-68cd3b85e05a47a2886f747a8ca9e549 |
| institution | Directory Open Access Journal |
| issn | 1930-2126 1930-2126 |
| language | English |
| last_indexed | 2024-12-23T04:45:57Z |
| publishDate | 2016-05-01 |
| publisher | North Carolina State University |
| record_format | Article |
| series | BioResources |
| spelling | doaj.art-68cd3b85e05a47a2886f747a8ca9e5492022-12-21T17:59:37ZengNorth Carolina State UniversityBioResources1930-21261930-21262016-05-011125381538810.15376/biores.11.2.5381-5388An Eco-Friendly Approach: Incorporating a Xylanase Stage at Various Places in ECF and Chlorine-based Bleaching of Eucalyptus PulpAvdhesh K. Gangwar0N. Tejo Prakash1Ranjana Prakash2Department of Biotechnology, Thapar University, Patiala, India; IndiaSchool of Energy and Environment, Thapar University, Patiala, India; IndiaSchool of Chemistry and Biochemistry, Thapar University, P. O. Box 32, Pin- 147004, Patiala, India; IndiaA potentially more environmentally compatible approach was evaluated, involving the use of an enzyme (X) stage optimally inserted into various bleaching sequences for Eucalyptus kraft pulps. The efficacy of the X stage was evaluated in terms of final brightness, CIE whiteness, post-color number (brightness reversion), effluent characteristics, etc. The results showed considerable benefits with an enzymatic pre-treatment bleaching sequence for improved final pulp brightness (1.6 units higher) and reduced adsorbable organic halogens (AOX) (32% lower), in addition to improved biological oxygen demand (BOD) to chemical oxygen demand (COD) ratio, when using 0.5 kg/t pulp dosage of xylanase; enzymatic post-treatment bleaching sequences were observed to boost final CIE whiteness up to 3.4 units and to reduce post color number by 48% at 0.5 kg/t pulp dosage of xylanase. In addition, approximately 32% reductions in AOX released, as well as appreciable improvement in BOD-to-COD ratio, were observed in the bleach effluents. An improved ratio of BOD-to-COD facilitates possible enhancement in the bio-degradability of discharge effluents in a secondary treatment stage. Nine different bleaching sequences were compared. Three sequences for each category (pre-treatment, intermediate, and post-treatment bleaching sequences) were performed to provide an overview of the influence of xylanase treatment on various pulp properties and environmental sum parameters of the ensuing effluents.http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_11_2_5381_Gangwar_Eco_Friendly_Approach_Xylanase_StageAdsorbable organic halides (AOX)Bleaching sequencesBiological oxygen demand (BOD)Chemical oxygen demand (COD)Optical propertiesXylanase |
| spellingShingle | Avdhesh K. Gangwar N. Tejo Prakash Ranjana Prakash An Eco-Friendly Approach: Incorporating a Xylanase Stage at Various Places in ECF and Chlorine-based Bleaching of Eucalyptus Pulp BioResources Adsorbable organic halides (AOX) Bleaching sequences Biological oxygen demand (BOD) Chemical oxygen demand (COD) Optical properties Xylanase |
| title | An Eco-Friendly Approach: Incorporating a Xylanase Stage at Various Places in ECF and Chlorine-based Bleaching of Eucalyptus Pulp |
| title_full | An Eco-Friendly Approach: Incorporating a Xylanase Stage at Various Places in ECF and Chlorine-based Bleaching of Eucalyptus Pulp |
| title_fullStr | An Eco-Friendly Approach: Incorporating a Xylanase Stage at Various Places in ECF and Chlorine-based Bleaching of Eucalyptus Pulp |
| title_full_unstemmed | An Eco-Friendly Approach: Incorporating a Xylanase Stage at Various Places in ECF and Chlorine-based Bleaching of Eucalyptus Pulp |
| title_short | An Eco-Friendly Approach: Incorporating a Xylanase Stage at Various Places in ECF and Chlorine-based Bleaching of Eucalyptus Pulp |
| title_sort | eco friendly approach incorporating a xylanase stage at various places in ecf and chlorine based bleaching of eucalyptus pulp |
| topic | Adsorbable organic halides (AOX) Bleaching sequences Biological oxygen demand (BOD) Chemical oxygen demand (COD) Optical properties Xylanase |
| url | http://ojs.cnr.ncsu.edu/index.php/BioRes/article/view/BioRes_11_2_5381_Gangwar_Eco_Friendly_Approach_Xylanase_Stage |
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