Haoxing Hu , Bingzheng Wang , Jiali Fang , Ziheng Feng , Huiyun Zhong , Ji Li
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引用次数: 0
Abstract
Sulfur-driven autotrophic denitrification (SAD) has been widely applied for treating low C/N wastewater. However, it faces issues like high alkalinity consumption and poor phosphorus removal. Steel slag, an industrial waste characterized by high alkalinity, high hardness and large specific surface area, has the potential to combine with the SAD process to enhance the removal efficiency of nitrogen and phosphorus. In this study, a steel slag/sulfur-based autotrophic denitrification (SS-SAD) reactor with different sulfur/steel slag ratios was set up to investigate the effects of steel slag on the nitrogen and phosphorus removal. The addition of steel slag significantly enhanced the nitrogen and phosphorus removal performance of the SAD process. The average NO3−-N removal efficiency of the SS-SAD reactor remained at over 99.0 % and the removal efficiency of PO43−-P could reach up to 85.2 %. The addition of steel slag promoted the secretion of extracellular polymeric substances, which was 34.2–51.3 mg/g VSS and the ratio of protein to polysaccharide was 6.0–18.9. The activity of relevant functional enzymes, nitrate reductase, nitrite reductase and sulfur oxidase, was also enhanced, which was 2.7–3.7, 0.8–1.1 and 3.3–5.4 U/g VSS, respectively. Autotrophic denitrifying bacteria, such as Ferritrophicum and Thiobacillus, could be effectively enriched after the addition of steel slag.
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