Dataset Information

Process optimization and effect of thermal, alkaline, H₂O₂ oxidation and combination pretreatment of sewage sludge on solubilization and anaerobic digestion.

ABSTRACT:

Background

This study investigated the feasibility of enhancing anaerobic digestion of sewage sludge with triple, dual, and individual pretreatment of waste activated sludge with heat, alkalinity, and hydrogen peroxide. These pretreatments disrupt sludge flocs, organisms' cell walls, extracellular polymeric substance, and intracellular organic matter, which increase biodegradability and hydrolysis rate of activate sludge. In addition, the influence of various variables on methane production was analyzed using the response surface methodology with the quadratic model. Eventually, an optimized temperature and chemical concentration for the highest methane production and lowest chemical usage is suggested.

Results

The highest amount of methane production was obtained from the sludge pretreated with triple pretreatment (heat (90 °C), alkaline (pH = 12), and hydrogen peroxide (30 mg H₂O₂/g TS)), which had better performance with 96% higher methane production than that of the control sample with temperature of 25 °C approximately and a pH = 8. Response surface methodology with a quadratic model was also used for analyzing the influence of temperature, pH, and hydrogen peroxide concentration on anaerobic digestion efficiency. It was revealed that the optimized temperature, pH, and hydrogen peroxide concentration for maximizing methane production and solubilization of sludge and minimizing thermal energy and chemical additives of the pretreatments are 83.2 °C, pH = 10.6 and 34.8 mg H₂O₂/g TS, respectively, has the desirability of 0.67.

Conclusion

This study reveals that triple pretreatment of waste activated sludge performed better than dual and individual pretreatment, respectively, in all desirable output parameters including increasing methane production as the most important output, increasing in COD solubilization, protein and polysaccharide, and decreasing in VSS solubilization.

SUBMITTER: Siami S

PROVIDER: S-EPMC7201573 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Publications

Process optimization and effect of thermal, alkaline, H<sub>2</sub>O<sub>2</sub> oxidation and combination pretreatment of sewage sludge on solubilization and anaerobic digestion.

Siami Salar S Aminzadeh Behnoush B Karimi Razieh R Hallaji Seyed Mostafa SM

BMC biotechnology 20200506 1

<h4>Background</h4>This study investigated the feasibility of enhancing anaerobic digestion of sewage sludge with triple, dual, and individual pretreatment of waste activated sludge with heat, alkalinity, and hydrogen peroxide. These pretreatments disrupt sludge flocs, organisms' cell walls, extracellular polymeric substance, and intracellular organic matter, which increase biodegradability and hydrolysis rate of activate sludge. In addition, the influence of various variables on methane product ...[more]

PMID: 32375744

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Project description:Anaerobic co-digestion (Co-AD) is used to increase the effectiveness of anaerobic digestion (AD) using local "wastes", adding economic and environmental benefits. Since system stability is of existential importance for the operation of wastewater treatment plants, thorough testing of potential co-substrates and their effects on the respective community and system performance is crucial for understanding and utilizing Co-AD to its best capacity. Food waste (FW) and canola lecithin (CL) were tested in mesophilic, lab-scale, semi-continuous reactors over a duration of 120 days with stepwise increased substrate addition. Key performance indicators (biogas, total/volatile solids, fatty acids) were monitored and combined with 16S-rRNA amplicon sequencing to assess the impact of co-substrate addition on reactor performance and microbial community composition (MCC). Additionally, the latter was then compared with natural shifts occurring in the wastewater treatment plant (WWTP, source) at the same time. An almost linear increase in biogas production with both co-substrates at an approximate 1:1 ratio with the organic loading rate (OLR) was observed. The MCCs in both experiments were mostly stable, but also prone to drift over time. The FW experiment MCC more closely resembled the original WWTP community and the observed shifts indicated high levels of functional redundancy. Exclusive to the CL co-substrate, a clear selection for a few operational taxonomic units (OTUs) was observed. There was little evidence for a persistent invasion and establishment of microorganisms from typical primary substrates into the stable resident community of the reactors, which is in line with earlier findings that suggested that the inoculum and history mostly define the MCC. However, external factors may still tip the scales in favor of a few r-strategists (e.g., Prolixibacter) in an environment that otherwise favors K-strategists, which may in fact also be recruited from the primary substrate (Trichococcus). In our study, specialization and diversity loss were also observed in response to the addition of the highly specialized CL, which in turn, may have adverse effects on the system's stability and reduced resilience and recovery.

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Dataset Information

Process optimization and effect of thermal, alkaline, H₂O₂ oxidation and combination pretreatment of sewage sludge on solubilization and anaerobic digestion.

Background

Results

Conclusion

Publications

Process optimization and effect of thermal, alkaline, H<sub>2</sub>O<sub>2</sub> oxidation and combination pretreatment of sewage sludge on solubilization and anaerobic digestion.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Process optimization and effect of thermal, alkaline, H2O2 oxidation and combination pretreatment of sewage sludge on solubilization and anaerobic digestion.

Background

Results

Conclusion

Publications

Process optimization and effect of thermal, alkaline, H<sub>2</sub>O<sub>2</sub> oxidation and combination pretreatment of sewage sludge on solubilization and anaerobic digestion.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Process optimization and effect of thermal, alkaline, H₂O₂ oxidation and combination pretreatment of sewage sludge on solubilization and anaerobic digestion.