Article
Environmental Sciences
Lei Zhang, Yiyang Yuan, Yingdi Zhang, Yang Liu
Summary: This study investigates the feasibility of using calcium hypochlorite (Ca(ClO)(2)) to improve the thermophilic digestion of anaerobic wasted activated sludge (WAS). The results show that Ca(ClO)(2) pretreatment significantly enhances the removal efficiency and methane yield of WAS under low organic loading rate (OLR) conditions. However, the pretreatment effect is not significant under high OLR conditions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Biotechnology & Applied Microbiology
Chandan Mahata, Suman Dhar, Subhabrata Ray, Debabrata Das
Summary: The performance of the upflow anaerobic sludge blanket (UASB) reactor for stable H2 production from starchy wastewater supplemented with groundnut de-oiled cake using mixed consortia was investigated in this study. Limited research on H2 production for UASB reactor has been reported. The operation of the UASB reactor was divided into start-up period and production period, with different hydraulic retention times (HRT) examined for H2 production. The maximum H2 production rate of 12.3 L L-1 d-1 was observed at 3 h HRT. Physicochemical characteristics of the granular sludge were studied, and advanced bio-kinetic models were implemented to analyze the substrate consumption on hydrogen production.
ENVIRONMENTAL TECHNOLOGY & INNOVATION
(2023)
Article
Agricultural Engineering
Jinsu Kim, Hyungmin Choi, Changsoo Lee
Summary: This study demonstrates the formation of conductive magnetite-embedded granular sludge and its positive impact on the performance of anaerobic sludge blanket reactors treating dairy wastewater. The magnetite-supplemented reactor showed better performance, with improved sludge settling and electron transport activity, as well as higher abundance of electroactive microbes. This study offers a new approach to enhance anaerobic granular sludge systems.
BIORESOURCE TECHNOLOGY
(2022)
Article
Agricultural Engineering
Om Prakash, Alsayed Mostafa, Seongwon Im, Seoktae Kang, Xueqing Shi, Dong-Hoon Kim
Summary: Autogenerative high-pressure digestion has the advantage of producing CH4-rich biogas directly. In this study, a continuous operation of upflow anaerobic sludge blanket reactor (UASB) was performed with pressure gradually increasing from 1 to 8 bar. The CH4 content in the biogas gradually increased with increasing pressure, reaching 96.7 ± 0.8% at 8 bar (309 MJ/m3 biogas). The physicochemical properties of granules were not adversely affected by the high pressure, and there was an increase in the production of extracellular polymeric substances (EPS) and carbonic anhydrase gene expression.
BIORESOURCE TECHNOLOGY
(2023)
Article
Agricultural Engineering
Xiangchen Li, Rui Du, Jingwen Zhang, Shuying Wang, Yongzhen Peng
Summary: This study combined nitrogen conversion, granular characteristics, and microbial dynamics to reveal the longitudinal heterogeneity of anammox-UASB. It was found that the bottom zone had larger and more mineralized granules, while the middle zone had smaller and more active granules. By combining partial denitrification and anammox, the performance in the top zone was improved.
BIORESOURCE TECHNOLOGY
(2022)
Article
Engineering, Environmental
A. Aishwarya Lakshmi, S. Sadarajan
Summary: This study investigates the potential of locust bean gum (LBG) in accelerating the startup of a novel upflow anaerobic sludge blanket (UASB) reactor for municipal sewage treatment. The results show that the reactor with LBG as an additive achieved an accelerated startup in 40 days, with higher COD removal efficiency compared to a conventional system. This confirms the positive impact of LBG on reactor startup.
WATER SCIENCE AND TECHNOLOGY
(2023)
Article
Environmental Sciences
Xiao Zhang, Bowei Zhao, Rui Li, Ying Cui, Fei Xie, Aijuan Zhou, Jinping Li, Xiuping Yue
Summary: The influence of hydraulic retention time (HRT) on the granulation process, methane-producing capacity, microbial community structure, and pollutant removal efficiency of an up-flow anaerobic sludge blanket (UASB) with simulated municipal wastewater was investigated. The results showed that even at low COD concentrations, the proportion of granular sludge in the UASB was high, and the COD removal efficiency was good. Shortening the HRT resulted in dense granular sludge and reduced the load of subsequent treatment processes.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Green & Sustainable Science & Technology
Philomina Mamley Adantey Arthur, Yacouba Konate, Boukary Sawadogo, Gideon Sagoe, Bismark Dwumfour-Asare, Issahaku Ahmed, Richard Bayitse, Kofi Ampomah-Benefo
Summary: Wastewater management in developing countries faces challenges due to insufficient infrastructure, necessitating economically viable and efficient technologies. The upflow anaerobic sludge blanket (UASB) reactor is a low-cost technology that produces valuable by-products. This study assessed the energy recovery potential from biogas and sludge by-products produced by a full-scale UASB reactor. The average biogas production was 611 +/- 275 Nm(3)/d, with 65% methane content, and the average sludge dry matter production was 358.24 TS kg/d. The estimated net energy recovery potential was 534.1 MWh/yr, surpassing the yearly energy demand of the plant.
Article
Environmental Sciences
Lingjiao Kong, Xianyang Shi
Summary: This study investigated the effects of three antibiotic mixtures on the performance, SMPs composition, and microbial community of UASBs. The results showed that antibiotic mixtures decreased the chemical oxygen demand removal efficiency and biogas content of the reactors, and influenced the composition and fluorescence intensity of SMPs. Moreover, antibiotics also had a significant impact on the microbial community structure.
Article
Biotechnology & Applied Microbiology
Shan Liu, Yongkang Wang, Jianbin Guo, Wei Wang, Renjie Dong
Summary: The study investigated the methanogenesis performance of UASB reactors started up using acidified granular sludge for treating SHTMS. The initial organic loading rate (OLR) significantly affected the degradation performance and microbial community variations in the reactors. High OLR led to lower methane conversion efficiency and higher VFA accumulation, while low OLR resulted in higher methane conversion efficiency and lower VFA accumulation. Adjusting OLR after successful start-up helped maintain stable methane conversion efficiency in the reactors.
BIOCHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Environmental
Wanmai Srisuwanno, Krittiya Pornmai, Kessara Seneesrisakul, Achiraya Jiraprasertwong, Malinee Leethochawalit, Pramoch Rangsunvijit, Sumaeth Chavadej
Summary: This study aimed to enhance the methanogenic activity of distillery wastewater with high potassium (K) content using a mesophilic three-stage upflow anaerobic sludge blanket (UASB). The three-stage UASB could not function properly at a chemical oxygen demand (COD) loading rate greater than 3 kg/m3d due to potassium toxicity. However, by diluting the wastewater to reach moderate K toxicity, the three-stage UASB was able to effectively function at high COD loading rates due to the development of adapted anaerobe communities.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Green & Sustainable Science & Technology
Georgios Manthos, Dimitris Zagklis, Vasiliki Papavasileiou, Nektaria Anastasia Gkountou, Zinovia Saita, Constantina Zafiri, Michael Kornaros
Summary: Olive mill effluents are a significant waste stream in Mediterranean countries and their uncontrolled disposal without treatment has adverse environmental and social impacts. Anaerobic digestion has been extensively researched for treating various waste streams, and its advantages include energy and fertilizer production. This study optimized the organic loading rate of anaerobic UASB digesters processing olive mill effluents, reaching a maximum of 5-6 gCOD/LR/d without pretreatment. The acclimatization of inoculum to the effluents also improved phenols degradation inside the reactor to 59%.
Article
Agricultural Engineering
Achiraya Jiraprasertwong, Pattaratorn Karnchanapaisal, Kessara Seneesrisakul, Pramoch Rangsunvigit, Sumaeth Chavadej
Summary: The study found that for treating ethanol wastewater using a two-phase UASB system, the optimal OLR was 32 kg m-3 d-1, resulting in high process activity and effectiveness. Sludge granulation was found to be beneficial for system operation and wastewater treatment efficiency. Additionally, factors such as pH value and lactic acid content were found to play important roles in granulation in the system.
BIOMASS & BIOENERGY
(2021)
Article
Ecology
Qingjuan Meng, Pengfei Li, Jianhua Qu, Ying Liu, Yifan Wang, Zhaobo Chen, Ying Zhang
Summary: This study successfully degraded TCE using a UASB reactor, with the anaerobic sludge containing a variety of bacteria including acid-forming bacteria, anaerobic dechlorinating bacteria, and methanogenic bacteria.
Article
Environmental Sciences
Takanori Omine, Kyohei Kuroda, Masashi Hatamoto, Takashi Yamaguchi, Masahito Yamauchi, Masayoshi Yamada
Summary: This study aimed to reduce the alkalinity supplementation for a thermophilic multi-feed up-flow anaerobic sludge blanket (MF UASB) reactor for the low-cost treatment of the wastewater from shochu distillation. The research found that the minimum alkalinity supplementation was 0.045 mgCaCO(3) mgCOD(-1) at an organic loading rate of 24 kgCOD m(-3) day(-1).
ENVIRONMENTAL TECHNOLOGY
(2021)