Cattle manure management using microbial fuel cells for green energy generation

Abstract

The increased use of estrogens in modern livestock farming has caused them to enter the environment and they have become a serious human health concern. Studies have suggested that animal waste treatment using bio-electrochemical systems may reduce their environmental impact. Bioelectrochemical systems hold great potential as green bioenergy conversion systems utilizing different biowastes as the feedstock. The present work involves the development of a laboratory-scale microbial fuel cell (MFC) for energy generation from two different cattle manures (cow dung and buffalo dung) as biowaste after ultrasonication pretreatment for a period ranging from 4 to 8 min. The maximum power density in both the cattle manures is reported with 5.5 min of ultrasonication pretreatment at 40 kHz, 120 W, at 25 °C. Two similar setups of a single-chambered membrane-less MFC were fed with pretreated cow dung (PCD) and pretreated buffalo dung (PBD) as substrates in the anodic chamber, and the effects of various parameters such as temperature and time were investigated. The maximum chemical oxygen demand and biochemical oxygen demand removal were 80% and 87% respectively, with PBD. The coulombic efficiency of PBD-MFC was slightly higher (0.53%) than that of PCD-MFC (0.48%). The maximum voltage (0.65 V) and power density (12.75 mW m −2 ) were also recorded with PBD-MFC. Energy recovery was also studied by electrically stacking five individual units of these MFCs into series and parallel arrangements. The parallel and series PBD-MFC stacks yielded 22 and 12 times higher power output respectively than the individual unit.

Ultrasonic pre-treatment of Bacillus velezensis for improved electrogenic response in a single chambered microbial fuel cell

“…They observed that the optimal COD and BOD levels were reduced by an average of 80% in both the cattle manures. The power output can also be increased by 22 times if 5 units are stacked in parallel (Syed et al 2021). All these studies have shown that the use of ultrasonication as a pre-treatment procedure on cathode material (activated carbon), substrate (rice mill water) for MFC and bovine manures yielded positive results in terms of energy generation.…”

“…The process of cavitation develops more quickly at a low-frequency level of 20 kHz to 40 kHz (Zhang et al 2007;Hawrylik and Butarewicz 2021). The application of low-frequency ultrasound has a broad range of applications in the field of biotechnology and environmental remediation (Foladori et al 2007;Hawrylik and Butarewicz 2021) including pre-treatment of electrode materials for improved electron transfer (Koo and Jung 2021), substrate modification (Raychaudhuri and Behera 2020) and microbial pre-treatment which all aimed towards better power generation in an MFC setup (Syed et al 2021).…”

Performance evaluation of Tagetes erecta plant microbial fuel cell using the composite ceramic anode of rice‐husk, mild‐steel dust, and soil

“…[13] reported buffalo dung as a low‐cost substrate containing large amounts of carbohydrates, an optimal C/N ratio and a rich microbial flora belonging to Firmicutes , Clostridia , Bacteroidetes and Proteobacteria . The presence of electrogens such as Purple photosynthetic bacteria in buffalo dung makes it a preferable substrate and a biocatalyst for higher power generation in MFC and also suitable as a biofertilizer promoting the plant growth [13]. The rich microbial flora and high C/N ratio may be the reasons for better power output.…”

“…Buffalo manure has been used in this study as the source of microbial flora for the PMFC operation. Syed et al [13] reported buffalo dung as a lowcost substrate containing large amounts of carbohydrates, an optimal C/N ratio and a rich microbial flora belonging to Firmicutes, Clostridia, Bacteroidetes and Proteobacteria.…”

“…In addition, the PMFC has the potential to expand into many wetlands and plains that are not suitable for agricultural production, and therefore, these can be converted into a power plant. Urban areas suffer from green coverage due to the rapid rate of development and expansion, which ends in poor air quality [10][11][12][13][14][15][16][17]. Thus, the diversity of vegetation that grows in urban areas, especially indoor and rooftop areas, can be a source of stagnant energy from PMFCs, generating living electricity and conserving our environment [18][19][20].…”