Dynamics of transitional acidogenic community along with methanogenic population during anaerobic digestion of swine wastewater

Anaerobic lagoons are natural wastewater treatment systems suitable for swine farms in small communities due to its low operational and building costs, as well as for the environmental sustainability that these technologies enable. The local weather is one of the factors which greatly influences the efficiency of the organic matter degradation within anaerobic lagoons, since microbial growth is closely related to temperature. In this manuscript, we propose a mathematical model which involves the two-dimensional Stokes, advection–diffusion-reaction and heat transfer equations for an unstirred fluid flow. Furthermore, the Anaerobic Digestion Model No1 (ADM1), developed by the International Water Association (IWA), has been implemented in the model. The partial differential equations resulting from the model, which involve a large number of state variables that change according to the position and the time, are solved through the use of the Finite Element Method. The results of the simulations indicated that the methodology is capable of predicting reasonably well the steady-state of the concentrations for all processes that take place in the anaerobic digestion and for each one of the variables considered; cells, organic matter, nutrients, etc. In view of the results, it can be concluded that the model has significant potential for the design and the study of anaerobic cells’ behaviour within free flow systems.

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Anaerobic digestion and post-treatment of swine wastewater using IC–SBR process with bypass of raw wastewater

Process Biochemistry ◽

10.1016/j.procbio.2005.10.022 ◽

2006 ◽

Vol 41 (4) ◽

pp. 965-969 ◽

Cited By ~ 73

Author(s):

Liang-Wei Deng ◽

Ping Zheng ◽

Zi-Ai Chen

Keyword(s):

Anaerobic Digestion ◽

Post Treatment ◽

Swine Wastewater ◽

Raw Wastewater

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Enhancing anaerobic digestion of dairy and swine wastewater by adding trace elements: evaluation in batch and continuous experiments

Water Science & Technology ◽

10.2166/wst.2019.420 ◽

2019 ◽

Vol 80 (9) ◽

pp. 1662-1672 ◽

Cited By ~ 3

Author(s):

Jing Wang ◽

Maria Westerholm ◽

Wei Qiao ◽

Ahmed Mahdy ◽

Simon M. Wandera ◽

...

Keyword(s):

Trace Elements ◽

Anaerobic Digestion ◽

Critical Role ◽

16S Rrna Gene Sequencing ◽

Swine Wastewater ◽

Rrna Gene ◽

Continuous Systems ◽

Batch Tests ◽

Rrna Gene Sequencing ◽

Low Dosage

Abstract Trace elements play a critical role for microbial activity in anaerobic digestion (AD) but their effects were probably overestimated in batch tests and should be comparably evaluated in continuous systems. In this study, Fe2+, Co2+, Ni2+, Cu2+ and Zn2+ were added in different concentrations to manure wastewater, and the effects were compared in both batch and continuous systems. The results were used to demonstrate suitable trace element compositions for AD of dairy and swine wastewater, and to compare the outcomes from batch and continuous systems. Fe2+ and Zn2+ were identified as being the most efficient stimulant of dairy and swine wastewater respectively. The addition of 5 mg/L Fe2+ and 0.4 mg/L Zn2+ increased the batch specific methane yield by 62% and 126% for dairy and swine wastewater, respectively. Nevertheless, a lower increment of 2% and 21%, for dairy and swine wastewater was obtained in the 120-day continuously-fed experiments. The 16S rRNA gene sequencing results indicated a relationship between the methanogens population, specific methanogenic activities, propionate, and dissolved hydrogen. Conclusively, the addition of a low dosage of Fe2+ and Zn2+ is a feasible strategy to enhance the methanogenic metabolism of the AD of dairy and swine wastewater respectively.

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