Asheesh Kumar Yadav

The effects of microbial fuel cell integration into constructed wetland on the performance of constructed wetland

The present work is the first detailed study, which is about the performance of CW after MFC integration with it. The experiments were run in open and closed circuit mode for assessment purpose. The findings of this study indicate towards a more practical application of MFC in wastewater treatment along with electricity production. The closed circuit operations of CW-MFCs have performed 12-20% better than open circuit operation and 27-49% better than Normal-CW for chemical oxygen demand (COD) removal. The maximum power density of 320.8 mW/m(3) and current density of 422.2 mA/m(3) have been achieved in granular graphite anode and Pt coated carbon cloth cathode based CW-MFC.

Removal of various pollutants from wastewater by electrocoagulation using iron and aluminium electrode

The present study deals with removal of various pollutants from a real wastewater by electrocoagulation treatment. Combined wastewater from one of the Delhi industrial areas was collected and treated by electrocoagulation process using iron and aluminium electrodes. Removal of Cr, Zn, Ni and Cu were achieved up to 100, 98.71, 69.22 and 48.08% respectively using aluminium electrode while Cr, Cu, Zn and Ni were removed up to 100, 78.57, 75.48 and 58.68% respectively using iron electrode electrocoagulation. Chemical oxygen demand, total organic carbon, total dissolved solids and sulphate were removed up to 83.94, 46.92, 74.16 and 83.66%, respectively in aluminium electrode electrocoagulation while the same were removed up to 54.83, 77.39, 52.85 and 60.74% respectively in iron electrode electrocoagulation.

Performance assessment of aeration and radial oxygen loss assisted cathode based integrated constructed wetland-microbial fuel cell systems

The present study explores low-cost cathode development possibility using radial oxygen loss (ROL) of Canna indica plants and intermittent aeration (IA) for wastewater treatment and electricity generation in constructed wetland-microbial fuel cell (CW-MFC) system. Two CW-MFC microcosms were developed. Amongst them, one microcosm was planted with Canna indica plants for evaluating the ROL dependent cathode reaction (CW-MFC dependent on ROL) and another microcosm was equipped with intermittent aeration for evaluating the intermittent aeration dependent cathode reaction (CW-MFC with additional IA). The CW-MFC with additional IA has achieved 78.71% and 53.23%, and CW-MFC dependent on ROL has achieved 72.17% and 46.77% COD removal from synthetic wastewater containing glucose loads of 0.7gL-1and 2.0gL-1, respectively. The maximum power density of 31.04mWm-3 and 19.60mWm-3 was achieved in CW-MFC with additional IA and CW-MFC dependent on ROL, respectively.

NH3 and COD removal from wastewater using biological process: kinetic with optimization studies

AbstractStudies on heterotrophic biomass conversion (HBC) process were carried out for the removal of N–NH3 and organic carbon from wastewater. Ammonium sulfate and glucose were used as nitrogen and organic sources, respectively. A range of parameters were studied such as time, concentration variations of N–NH3, and organic nutrients keeping the biomass (total volatile suspended solids, TVSS) concentration invariable in all the cases. The kinetics followed dual rates, i.e. an initial faster phase, followed by the slower one. The rates of N–NH3 and chemical oxygen demand (COD) removal depended on their initial concentrations. The consumption of N–NH3 and COD followed first order kinetics. The unified rate equation was also established. Two other kinetic models, such as Monod and diffusion, were studied. The pH during the HBC process showed a decreasing trend. Other parameters studied were: , N2O, , and DO. A part of N–NH3 utilized for emission of N2O may be due to heterotrophic nitrification (HN). Statisti...

The Performance Improvement of Microbial Fuel Cells Using Different Waste-Sludge as an Inoculum

The performance evaluation of microbial fuel cells with three different waste sludge as mixed inoculum under both untreated and pretreated conditions reveals that these sludge have potential bacterial communities to produce bio-electricity and chemical oxygen demand removal for waste water treatment. The heat and acid pretreatment to the inoculum of these sludge resulted in higher electricity yield along with reduction in time in comparison to that with untreated ones.

Kinetics with optimization studies of nitrogen and organic elimination from wastewater via heterotrophic biomass conversion process

AbstractHeterotrophic biomass conversion (HBC) research was carried out for the removal of N-NH3 and organic carbon from synthetic wastewater. Ammonium nitrate and glucose were used as the nitrogen and organic carbon source, respectively. In this study, N-NH3 and organic nutrient concentrations were varied, keeping the biomass concentration invariable. The kinetics followed dual rates, i.e. faster initial rate followed by a slower one. The consumption of N-NH3 and COD followed first-order kinetics. Kinetic model such as Monod was studied. The pH during the HBC process showed an increasing trend which may be due to heterotrophic nitrification (HN). Parameters like N-, N2O, N-, time, and dissolved oxygen were studied. A part of N-NH3 utilized for the emission of N2O may be due to HN. Analyses of variance were carried out for better interpretation of results. Optimization studies were carried out to minimize N2O emission and maximize N-NH3 along with COD removal.

Constructed Wetland Coupled Microbial Fuel Cell Technology

Traditional wastewater treatments require high energy, operation, and maintenance costs and produce a large amount of sludge during treatment. This situation is becoming more complex with increasing population growth and urban areas. Thus, a new paradigm of water-energy nexus is required to meet the new water and energy demands at an affordable cost. The constructed wetlands (CWs) or treatment wetlands are low cost engineered systems that are designed to utilize the natural processes for wastewater treatment. In general, CWs run without any chemical dosing or external energy requirements and are easy to operate and maintain. Thus, CWs need very less cost for operation. The CWs have been established in a large number throughout the world as an alternative to the conventional wastewater treatment systems [1,2]. The foundation of CWs for the wastewater treatment technology was laid by early experiments of Dr. Kӓthe Seidel in the 1960s [3] and by Reinhold Kickuth in the 1970s [4,5]. At the beginning of CW establishment, the CWs were mainly used for the treatment of traditional tertiary and secondary domestic/municipal wastewaters [6]. The early types of CW were often dominated by free water surface CWs in North America and horizontal subsurface flow (HSSF) CWs in Europe and Australia [7,8]. In later years, the application of CWs has also been significantly stretched to purify agricultural effluents [9,10], industrial effluents [11,12]; landfill leachates [13]; agricultural drainage waters [14,15]; acid mine drainage [16]; aquaculture waters [17]; and urban and highway runoff [18,19].

Algal-assisted Microbial Fuel Cell for Wastewater Treatment and Bioelectricity Generation

The aim of the present work was to design a self-sustainable, low-cost microbial fuel cell using a blue green algae-assisted cathode as a substitute for chemical oxidant. The idea was to utilize the oxygen produced during photosynthesis by algae as an oxidant in the cathode chamber. Results successfully demonstrated that the algae-assisted microbial fuel cell is efficient for electricity generation and chemical oxygen demand removal from wastewater. The performance of a developed microbial fuel cell resulted in a maximum current density of 149.5 mA m−2 and power density of 78.12 mW m−2. Dissolved oxygen concentration in cathode solution achieved in the range of 3.5 to 5.5 mg l−1. Furthermore, other species of algae like oil-algae can be grown in a cathode chamber, which can be used for bio-diesel production and greenhouse gas like CO2 sequestering. Further works are under progress on this aspect in our research group.