Tiago B Ferreira, Fabiana Passos, Cláudio L de Souza
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引用次数: 0
Abstract
Decentralized anaerobic treatment presents a sustainable alternative for managing the substantial generation of food waste. However, the associated high costs may render this option less feasible for small- to medium-scale systems. To explore a novel strategy for cost reduction in anaerobic digestion systems used for food waste treatment, this study applied organic loading rates (OLR) ranged from 0.6-1.9 kg VS m⁻³ d⁻¹ in a reactor under non-conventional conditions combined in anaerobic reactors: non-controlled temperature and pH, intermittent mixing, semi-continuous feeding, and biomass sedimentation. To evaluate the reactor's performance for 194 days, key parameters such as process stability, volatile solids (VS) removal, methane production, and biomass accumulation were monitored. Throughout the operation, the reactor temperature fluctuated between 19 and 36 °C, while the sludge retention time (SRT) values were up to 140% higher than the hydraulic retention time (HRT), indicating effective decoupling compared to the equal SRT and HRT observed in the conventional continuous stirred tank reactor (CSTR) model. Compared to conventional CSTR operation, the intermittent mixing approach still achieved an 80% reduction in mixing energy requirements. The results demonstrated that the optimal conditions were achieved at an OLR of 1.5 kg VS m⁻³ d⁻¹ and an HRT of 36 days. Under these conditions, a VS removal efficiency of 82% was obtained, with a methane production rate of 0.645 m³ CH₄ m⁻³ d⁻¹. Overall, the anaerobic reactor demonstrated stable performance under simplified operational strategies, reaching efficiencies comparable to conventional mesophilic systems with temperature control and alkalinity supplementation.
分散式厌氧处理为管理大量产生的食物垃圾提供了一种可持续的替代方案。然而,相关的高成本可能会使这种选择在中小型系统中不太可行。为了探索用于食物垃圾处理的厌氧消化系统降低成本的新策略,本研究在厌氧反应器的非常规条件下应用了0.6-1.9 kg VS m的有机负载率(OLR):不控制温度和pH值,间歇混合,半连续进料和生物质沉淀。为了评估194天的反应器性能,监测了过程稳定性、挥发性固体(VS)去除率、甲烷产量和生物质积累等关键参数。在整个运行过程中,反应器温度在19 ~ 36°C之间波动,而污泥滞留时间(SRT)值比水力滞留时间(HRT)高出140%,与传统连续搅拌槽式反应器(CSTR)模型中观察到的相等的SRT和HRT相比,表明了有效的解耦合。与传统的CSTR操作相比,间歇混合方法仍然可以减少80%的混合能量需求。结果表明,最适宜的条件是OLR为1.5 kg VS m⁻³,HRT为36天。在此条件下,VS的去除率为82%,产甲烷率为0.645 m³CH₄m⁻³d⁻¹。总的来说,在简化的操作策略下,厌氧反应器表现出稳定的性能,达到了与传统的温度控制和碱度补充系统相当的效率。
期刊介绍:
Environmental Technology is a leading journal for the rapid publication of science and technology papers on a wide range of topics in applied environmental studies, from environmental engineering to environmental biotechnology, the circular economy, municipal and industrial wastewater management, drinking-water treatment, air- and water-pollution control, solid-waste management, industrial hygiene and associated technologies.
Environmental Technology is intended to provide rapid publication of new developments in environmental technology. The journal has an international readership with a broad scientific base. Contributions will be accepted from scientists and engineers in industry, government and universities. Accepted manuscripts are generally published within four months.
Please note that Environmental Technology does not publish any review papers unless for a specified special issue which is decided by the Editor. Please do submit your review papers to our sister journal Environmental Technology Reviews at http://www.tandfonline.com/toc/tetr20/current