AOX removal from pulp and paper wastewater by Fenton and photo-Fenton processes: A real case-study

AbstractXylanases are widely used enzymes in the food, textile, and paper industries. Most efficient xylanases have been identified from lignocellulose-degrading microbiota, such as the microbiota of the cow rumen and the termite hindgut. Xylanase genes from efficient pulp and paper wastewater treatment (PPWT) microbiota have been previously recovered by metagenomics, assigning most of the xylanase genes to the GH10 family. In this study, a total of 40 GH10 family xylanase genes derived from a certain PPWT microbiota were cloned and expressed in Escherichia coli BL21 (DE3). Among these xylanase genes, 14 showed xylanase activity on beechwood substrate. Two of these, PW-xyl9 and PW-xyl37, showed high activities, and were purified to evaluate their xylanase properties. Values of optimal pH and temperature for PW-xyl9 were pH 7 and 60 ℃, respectively, while those for PW-xyl37 were pH 7 and 55 ℃, respectively; their specific xylanase activities under optimal conditions were 470.1 U/mg protein and 113.7 U/mg protein, respectively. Furthermore, the Km values of PW-xyl9 and PW-xyl37 were determined as 8.02 and 18.8 g/L, respectively. The characterization of these two xylanases paves the way for potential application in future pulp and paper production and other industries, indicating that PPWT microbiota has been an undiscovered reservoir of efficient lignocellulase genes. This study demonstrates that a metagenomic approach has the potential to screen efficient xylanases of uncultured microorganisms from lignocellulose-degrading microbiota. In a similar way, other efficient lignocellulase genes might be identified from PPWT treatment microbiota in the future.

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Semantic and knowledge based support to business model evaluation to stimulate green behaviour of electric vehicles’ drivers and energy prosumers

Journal of Ambient Intelligence and Humanized Computing ◽

10.1007/s12652-021-03243-4 ◽

2021 ◽

Author(s):

Beniamino Di Martino ◽

Dario Branco ◽

Luigi Colucci Cante ◽

Salvatore Venticinque ◽

Reinhard Scholten ◽

...

Keyword(s):

Business Model ◽

Model Evaluation ◽

Business Models ◽

Real Case ◽

Sustainable Mobility ◽

Semantic Framework ◽

Knowledge Based ◽

Survey Results ◽

Energy Prosumers

AbstractThis paper proposes a semantic framework for Business Model evaluation and its application to a real case study in the context of smart energy and sustainable mobility. It presents an ontology based representation of an original business model and examples of inferential rules for knowledge extraction and automatic population of the ontology. The real case study belongs to the GreenCharge European Project, that in these last years is proposing some original business models to promote sustainable e-mobility plans. An original OWL Ontology contains all relevant Business Model concepts referring to GreenCharge’s domain, including a semantic description of TestCards, survey results and inferential rules.

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Controlling the Settling of Activated Sludge in Pulp and Paper Wastewater Treatment Plants

Water Science & Technology ◽

10.2166/wst.1999.0716 ◽

1999 ◽

Vol 40 (11-12) ◽

pp. 223-229 ◽

Cited By ~ 8

Author(s):

Frédéric Clauss ◽

Christel Balavoine ◽

Delphine Hélaine ◽

Gaëtan Martin

Keyword(s):

Wastewater Treatment ◽

Activated Sludge ◽

Wastewater Treatment Plants ◽

Pulp And Paper ◽

Organic Load ◽

Forest Industry ◽

Filamentous Bulking ◽

Mineral Particles ◽

Mineral Powder

Forest industry wastewaters are difficult to clean: hydraulic and organic load variations, filamentous bulking or pin-point flocs negatively impact depollution processes. The addition of a fine, mineral, talc-based powder, Aquatal, into the aeration tanks of wastewater treatment plants connected to pulp and paper factories has been successfully tested since end of '97. The first case-study presents full results obtained over a period of 18 months in a 20,000 p.e. plant connected to a paper factory. The mineral powder was regularly added to control sludge volume index, thereby ensuring low suspended solids concentration in the outfluent. Plant operators could easily adapt biomass concentration to match organic load variation, thereby maintaining pollution micro-organisms ratio constant. In a second case study, a trouble-shooting strategy was implemented to counteract filamentous bulking. A one-off, large dosage enabled the plant operator to deal effectively with poor settleability sludge and rapidly control sludge blanket expansion. In both cases, the main common characteristics observed were an increase in floc aggregation and the production of heavier and well-structured flocs. The sludge settling velocity increased and an efficient solid/liquid separation was obtained. After a few days, the mineral particles of Aquatal were progressively integrated into the sludge floc structure. When the mineral powder was added to the activated sludge in the aeration basin, chemical interactions frequently encountered with other wastewater treatment additives did not pose a problem. Moreover, with this mineral additive, the biological excess sludge displayed good thickening properties and dewatering was improved. Despite the addition of the insoluble mineral particles, the amount of wet sludge expelled did not increase. Aquatal offers a rapid solution to floc settleability problems which so frequently arise when physical or biological disorders appear in forest industry wastewater treatment plants.

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A robust optimization framework for energy hub operation considering different time resolutions: A real case study

Sustainable Energy Grids and Networks ◽

10.1016/j.segan.2021.100526 ◽

2021 ◽

pp. 100526

Author(s):

Hamed Asgarian Honarmand ◽

Ahmad Ghaderi Shamim ◽

Hassan Meyar-Naimi

Keyword(s):

Robust Optimization ◽

Real Case ◽

Energy Hub ◽

Optimization Framework

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The combined use of magnetic field and iron-based complex in advanced treatment of pulp and paper wastewater

Chemical Engineering Journal ◽

10.1016/j.cej.2011.10.058 ◽

2011 ◽

Vol 178 ◽

pp. 232-238 ◽

Cited By ~ 14

Author(s):

Bo Liu ◽

Baoyu Gao ◽

Xing Xu ◽

Wei Hong ◽

Qinyan Yue ◽

...

Keyword(s):

Magnetic Field ◽

Pulp And Paper ◽

Advanced Treatment ◽

Combined Use ◽

Paper Wastewater ◽

Iron Based

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Testing the validity of different synthetic scenarios for flow and transport simulation in karst systems using a real case study application.

10.5194/egusphere-egu21-8769 ◽

2021 ◽

Author(s):

Joanna Doummar ◽

Nidal Farran ◽

Marwan Fahs ◽

Benjamin Belfort ◽

Thomas Graf

Keyword(s):

Real Case ◽

Richards Equation ◽

Model Quality ◽

Transient Model ◽

Flow And Transport ◽

Event Time ◽

Model Flow ◽

Karst Systems ◽

The Impact

<p>Climate change and pollution are posing additional unprecedented threats to existing water resources, especially to water supply from karst aquifers in Mediterranean and semi-arid regions. A numerical model considering the most important key hydraulic parameters can forecast the impact of any given input on model quality and quantity output. In this work, we propose to model flow and transport using Comsol multiphysics in a synthetic model and to apply it to a simplified real case study (Jeita spring in Lebanon supplying water to 1.5 million inhabitants). The model geometry consists of a 5300 m long variably saturated horizontal conduit portrayed as 1) 2-D continuum and/or 2) a channel draining a porous equivalent matrix (400 m thick). Flow is simulated using the Richards Equation in both saturated and unsaturated medium. Recharge is applied vertically as both diffuse and point source in a shaft linked to the conduit. Percentages of fast infiltration rates are obtained from the analysis of event time series recorded at the spring (electrical conductivity and discharge). Flow rates at the outlet are used for transient model calibration. Mean velocities, dispersivities, and phreatic conduit diameters obtained from tracer experiments under various flow periods are used for transport validation in the channel. The aim is to test the validity of a functional simplified flow model on a complex real case and to identify based on a sensitivity analysis the key parameters that allow an optimal calibration of such a model.&#160;</p>

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