Laura G. Covinich , Paola A. Massa , Ana M. Ferro Orozco , Fernando E. Felissia , María C. Area
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引用次数: 0
Abstract
This study developed a combined Advanced Oxidation Process (AOP)/biological treatment to reduce the recalcitrant organic load in an industrial black liquor from alkaline sulfite pulping. The methodology involved a Fenton-type reaction using a 2.5 % CuO/γ-Al2O3 catalyst, optimized to minimize Cu2+ leaching (reduced Cu2+ leaching from 8.2 mg/L to 1.0 mg/L) and maximize catalyst reuse. The catalyst demonstrated high stability, maintaining effectiveness for up to five cycles. The optimized Fenton pre-treatment enhanced biodegradability, increasing the Biological Oxygen Demand/COD ratio to 0.23 (initial ratio of 0.05), and exhibited minimal toxicity to the microbial community. Subsequent biological treatment was carried out using activated sludge cultured in an aerobic laboratory-scale reactor with partial biomass recycling. Operating conditions were 80 °C, 65.1 mg/L of supported copper (0.32 g of catalyst) and 3.23 g/L of H2O2. The combined AOP/biological system achieved a global 86 % TOC reduction and 93 % COD reduction. With the combination of processes, the current Argentine regulations regarding COD levels in industrial discharges are complied with, adhering to the maximum allowed limit of 250 mg/L in most provinces. Although some Cu leaching occurred, the dissolved copper retained catalytic activity, likely due to complexation with oxidation intermediates. The biological stage effectively treated the pre-oxidized liquor without requiring biomass acclimatization, maintaining microbial activity. These findings confirm the long-term viability of this integrated treatment for industrial applications. Future work should focus on scaling up the process, particularly addressing agitation requirements during the AOP stage.
期刊介绍:
The Journal of Water Process Engineering aims to publish refereed, high-quality research papers with significant novelty and impact in all areas of the engineering of water and wastewater processing . Papers on advanced and novel treatment processes and technologies are particularly welcome. The Journal considers papers in areas such as nanotechnology and biotechnology applications in water, novel oxidation and separation processes, membrane processes (except those for desalination) , catalytic processes for the removal of water contaminants, sustainable processes, water reuse and recycling, water use and wastewater minimization, integrated/hybrid technology, process modeling of water treatment and novel treatment processes. Submissions on the subject of adsorbents, including standard measurements of adsorption kinetics and equilibrium will only be considered if there is a genuine case for novelty and contribution, for example highly novel, sustainable adsorbents and their use: papers on activated carbon-type materials derived from natural matter, or surfactant-modified clays and related minerals, would not fulfil this criterion. The Journal particularly welcomes contributions involving environmentally, economically and socially sustainable technology for water treatment, including those which are energy-efficient, with minimal or no chemical consumption, and capable of water recycling and reuse that minimizes the direct disposal of wastewater to the aquatic environment. Papers that describe novel ideas for solving issues related to water quality and availability are also welcome, as are those that show the transfer of techniques from other disciplines. The Journal will consider papers dealing with processes for various water matrices including drinking water (except desalination), domestic, urban and industrial wastewaters, in addition to their residues. It is expected that the journal will be of particular relevance to chemical and process engineers working in the field. The Journal welcomes Full Text papers, Short Communications, State-of-the-Art Reviews and Letters to Editors and Case Studies