Department of Chemistry

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

CO2 Research and Green Technologies Centre

The quantity of fossil fuel is declining year by year, and the pollutant also released to the environment which insist on the exploration of new alternative fuel. Biodiesel from non-edible seeds is of primary concern for increasing prices of crude oil and thereof preventing greenhouse gas emissions. In the present study, the production of biodiesel by In-situ acid catalyzed transesterification from Sterculia foetida oil and seeds were reported. GC-FID characterization of oil sample revealed the presence of long-chain fatty acids with a higher proportion of sterculic acid (32%). The operating parameters in acid transesterification process viz., the weight of the oil and biomass, solvent volume, acid volume, temperature and time were optimized using Placket-Burman design. The maximum biodiesel yield obtained for sterculia oil and seeds were 91.58% and 95.91% exhibiting volume of oil being the critical factor based on Plackett-Burman design. One-way ANOVA analysis showed that chosen parameters were statistically significant (P &lt; .05) except for temperature. FT-IR analysis confirms the presence of biodiesel (1741 cm–1) obtained from the transesterification process. © 2019, © 2019 Taylor & Francis Group, LLC.

Vellore Campus

International Journal of Green Energy

In situ acid catalysed transesterification of biodiesel production from Sterculia foetida oil and seed

An experimental investigation of a two stage desalination-cooling (TSDC) plant assisted by solar flat plate collectors (SFPC) is reported. From the experimental study the total power consumption, desalination yield, and cooling output were estimated. The potential of a concentrating photovoltaic thermal (CPVT)collector to achieve possible reduction in power consumption of the TSDC plant was explored for the same desalination and cooling output. A mathematical model of CPVT collector assisted TSDC plant was developed and validated. Both configurations are compared in terms of specific water production and plant energy utilisation factor (EUF). This study reveals that the highest specific water production and EUF of CPVT assisted plant are 0.12 kg/m2-h and 0.23. For SFPC assisted plant the highest specific water production and EUF are 0.11 kg/m2-h and 0.11 respectively. The use of CPVT collector in lieu of SFPC to operate the TSDC plant results in higher specific water production and energy utilisation factor. A lesser amount of electrical energy and collector area is sufficient to operate the TSDC plant assisted by CPVT collector compared to SFPC assisted plant for same output. © 2019 Desalination Publications. All rights reserved.

VIT Unitversity

Department of Smart Computing

School of Information Technology and Engineering

DESALINATION AND WATER TREATMENT

Performance analysis of combined two stage desalination and cooling plant with different solar collectors

The performance of fixed film bioreactor on bioreduction of Cr(VI) was evaluated. The reactor was operated under batch and continuous mode. Influent contained glucose as the single carbon source. The maximum specific growth rate obtained was 7.16 mg L-1. The half saturation constant for COD was 475 mg L-1. The yield coefficient was found to be 0.209. A maximum biomass of 457 h-1 was obtained for Cr(VI) free cells. Both the reactor performed better under an hydraulic retention time of 24 h. Near complete reduction of Cr(VI) was reported for an initial Cr(VI) concentration of 10 and 20 mg L-1. The maximum number of suspended cells reported was 4.3 × 1014 at an Cr(VI) loading rate of 240 mg L-1day-1. The maximum amount of attached and suspended cells reported was 2013 and 238 mg. A maximum COD reduction of 84.1% was reported. The lag period for growth of cells under a Cr(VI) load ranging up to 40 mg L-1 was 3 h. © 2018 Elsevier Ltd.

World University root node

Journal of Environmental Chemical Engineering

Performance of Halomonas sp. to reduce hexavalent chromium in batch and continuous fixed film reactor

Anaerobic co-digestion of kitchen waste (KW) and wastewater sludge (WS) at different total solids ratios of 1:0, 1:1, 0:1 was conducted under mesophilic temperature conditions (35 ± 1 °C). The co-digestion of kitchen waste and wastewater sludge showed enriched methane gas generation when compared with individual anaerobic digestion of kitchen waste and wastewater sludge individually. The optimum ratio of kitchen waste to wastewater sludge was 1:1. The methane gas yield at 1:1 loading of kitchen waste to wastewater sludge was 43.6%. The total nitrogen content for sludge was 1820 mg/kg. The total nitrogen content of blended was 2180 mg/kg. Cr, Cd, Pb, Mg and Zn were in the kitchen waste and wastewater sludge. © 2016 Informa UK Limited, trading as Taylor &amp; Francis Group.

Biofuels

Anaerobic co-digestion of kitchen waste and wastewater sludge: biogas-based power generation

Production of fatty acid methyl esters from pongamia oil through trans-esterification was reported in this paper. The GC - MS analysis of oil was studied and the major fatty acids content was found to be 12.25% by weight. The molecular weight of the oil was 887.039 g/mol. A maximum yield of 85% biodiesel was reported when the reaction temperature, time, methanol/oil ratio and catalyst loading rate were 60°C, 45 min, 12:1 and 0.5% by (wt. %) respectively. The low cost pisthia shell catalyst was prepared and characterised in the laboratory setup. Partial purification of the fatty acid methyl esters was proposed for increasing the purity of the biodiesel and better engine performance and that was obtained from the oil firm itself. The flash point and the fire point of the biodiesel were found to be 172°C and 225°C, respectively. The brake thermal efficiency of B10 blend of biodiesel was 34% for maximum load, specific fuel consumption for diesel was 0.55 kg/kWhr at maximum load and for the blend of B50. The use of biodiesel blends showed a reduction of carbon monoxide and hydrocarbon emissions and a marginal increase in nitrogen oxides (NOx) emissions. Copyright © 2018 Inderscience Enterprises Ltd.

International Journal of Environment and Sustainable Development

Biodiesel production and characterisation from Pongamia oil using low cost Pisthia shell catalyst: engine performance and emission studies

Numerical investigation of unsteady buoyancy driven indoor air flow characteristics under various range of internal heat generation

A low cost and user friendly solar tunnel dryer was fabricated for drying of indigenous agro products. Experimental investigation and drying kinetics of turmeric (Curcuma longa) in a mixed mode solar tunnel dryer is reported. The key advantage of the current design is the inclination of the solar air heater which effective harnessing of solar radiation. The presence of detachable trays helps in easy handling of drying samples. The turmeric with an average initial moisture content of 0.779 (kg water/kg dry matter) were dried to 0.070 (kg water/kg dry matter) in the solar tunnel dryer under forced convection. Final drying levels of turmeric were realized in 12 h in the solar dryer while it took 43 h under the open sun drying. Thin layer drying kinetics of turmeric under forced solar tunnel drying was performed. The energy and exergy analysis during the drying process was assessed by employing the first and second law of thermodynamics. Energy utilization ratio of solar tunnel varied in the range of 9.75–33.98%. The mean value of exergetic efficiency of dryer was found to be 49.12%. © 2018 Elsevier Ltd

Renewable Energy

Thin layer drying kinetics and exergy analysis of turmeric (Curcuma longa) in a mixed mode forced convection solar tunnel dryer

The effect of stacking multiple microbial fuel cells for stable power output was evaluated in continuous mode operation. Three single chambered air cathode CMFCs with Nafion (CMFCN), Terry cotton (CMFCT) as membranes and one without membrane (CMFCML) were operated in continuous mode. Maximum power density (PD) and COD removal efficiency was obtained for CMFCN (0.1 W/m2, 50%) followed by CMFCML (0.062 W/m2, 47%) and CMFCT (0.025 W/m2, 39%) and were stable throughout the operation. To increase the power output further, stacking of CMFCs was carried in series/parallel circuitry, which yielded high power density in parallel (2.0 W/m2; 7.2 W/m3) and high voltage in series (1.1 V). Study also evidenced that stacking resulted in high and stable bioelectricity by minimizing the electron losses in comparison to individual CMFCs operation. Stable and high power output signifies the impact of continuous mode operation that constantlty replenishes the substrate. © 2018 Elsevier Ltd

Bioresource Technology

Stacking of microbial fuel cells with continuous mode operation for higher bioelectrogenic activity

This paper aims to contribute to developing a potential combined cycle air-breathing engine integrated into an aircraft design, capable of performing flight profiles on a commercial scale. This study specifically focuses on the single expansion ramp nozzle (SERN) and aircraft-engine integration with an emphasis on the combined cycle engine integration into the conceptual aircraft design. A parametric study using computational fluid dynamics (CFD) have been employed to analyze the sensitivity of the SERN’s performance parameters with changing geometry and operating conditions. The SERN adapted to the different operating conditions and was able to retain its performance throughout the altitude simulated. The expansion ramp shape, angle, exit area, and cowl shape influenced the thrust substantially. The internal nozzle expansion and expansion ramp had a significant effect on the lift and moment performance. An optimized SERN was assembled into a scramjet and was subject to various nozzle inflow conditions, to which combustion flow from twin strut injectors produced the best thrust performance. Side fence studies observed longer and diverging side fences to produce extra thrust compared to small and straight fences. © 2018 by the authors.

Fulltext

Energies

Modelling a hypersonic single expansion ramp nozzle of a hypersonic aircraft through parametric studies

In this study, the effect of different modes of cultivation viz., photoautotrophic (AT), heterotrophic (HT) and photomixotrophic (MT), on the growth and biochemical responses of Chlorella sp. isolated from local ponds. The performance of microalgal growth was quantified using nonlinear growth models such as Gompertz, logistic, Baranyi-Roberts, Morgan under different cultivation conditions. The results revealed that microalgae could grow better in MT than in other cultivation modes with a major increase in biochemical responses for carbohydrates, which showed higher accumulation under HT. The maximum biomass concentration was 1.24 g L-1 (MT), 1.16 g L-1 (HT), 0.76 g L-1 (AT) with maximum specific growth rates of 0.0083 h-1 (HT), 0.0078 h-1 (MT) and 0.0055 h-1 (AT) respectively. The biomass concentration was higher in the order of MT&gt;HT&gt;AT for which MT yielded 8.8 fold higher biomass, compared with the initial biomass concentration, at the end of experiments (16 days). Concomitant increases in biochemical responses were observed in the three cultivation conditions. Protein and lipid accumulation in the MT mode was higher (1.2 fold) compared with the initial protein yield as well as the other cultivation modes. However, the carbohydrate yield was higher (1.12 fold) in the heterotrophic mode than in other cultivation conditions. © 2018 Assoc. Brasiliera de Eng. Quimica / Braz. Soc. Chem. Eng.. All rights reserved.