BITS Faculty Publications
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Item Carbonaceous catalysts (biochar and activated carbon) from agricultural residues and their application in production of biodiesel: A review(Elsevier, 2024-03) Chatterjee, Somak; Roy, BanasriCarbonaceous catalysts obtained from agricultural residue could have potential in the production of biofuels such as biodiesel. This review paper discusses the preparation conditions (temperature, heating rate, hold time, inert gas flow rate, etc play key roles in development of textural characteristics of the catalysts) and functionalization methods of biochar and activated carbon derived from agricultural residues and their application to produce biodiesel. Research works reported in achieving maximum yield of biodiesel in terms of variable precursors, alcohol-to-oil ratio, reaction time and temperatures have been profoundly tabulated. Effect of textural properties of the biochar and activated carbon (such as surface area, total pore volume, average pore size, and functional group attached with the catalyst) on the biodiesel yield are examined. Studies on Regeneration and reusing of the spent catalysts are carefully inspected. The economic evaluation studies for the biochar and activated carbon and the applications of these for biodiesel production are scrutinized. Finally, the strategies to increase biomass and catalyst productivity, future prospect and research directions to enhance biofuel/biodiesel production and for the development of biochar and activated carbon from agricultural residues for sustainable biodiesel production is suggested.Item An experimental investigation of biodiesel-biogas dual-fuel engine based on energy and exergy analysis(Inder Science, 2018-06) Verma, SaketIn the present work, exergy analysis has been performed on the biodiesel-biogas dual fuel (DF) engine. The DF operation has been studied with biodiesel (Jatropha curcas) as the pilot fuel to ignite the main fuel (biogas). The experiments were performed at a constant engine speed of 1500 rpm with varying engine loads and optimised injection timings for both diesel and DF modes. The results indicate that DF operation at low load produces poor performance and emission characteristics, however, no significant variations were observed between diesel-DF and biodiesel-DF operations. At 23% of engine load, exergy efficiencies were found to be 8.53% and 8.4% for diesel-DF and biodiesel-DF operations respectively; compared to 12.57% for pure diesel operation. Nevertheless, at higher loads, exergetic performances of DF operations were significantly improved. Furthermore, oxides of nitrogen (NOx) emissions from DF operations were significantly reduced compared to that with diesel operation.Item Effect of Hydrogen Enrichment Strategy on Performance and Emission Features of Biodiesel-Biogas Dual Fuel Engine Using Simulation and Experimental Analyses(ASME, 2020-12) Verma, SaketIn the present work, hydrogen enrichment in biogas is studied as a potential approach to improve the performance and emission features of a biodiesel-biogas dual fuel engine. A single-cylinder diesel engine is modified to operate in dual fuel mode using Jatropha curcas biodiesel as the pilot fuel and biogas as the main fuel. An electronic control unit is developed in-house to study 5−20% hydrogen enrichment in biogas using the timed manifold injection (TMI) technique. A three-dimensional computational fluid dynamics-based simulation methodology is presented for optimal selection of TMI parameters to ensure efficient and safe operation of the engine. Subsequently, the optimized injection conditions are used for the experimental evaluations, which are performed for performance and emission characteristics of the engine at low and high engine loads. Engine performance is analyzed based on energy and exergy analyses, whereas hydrocarbon (HC), carbon monoxide (CO), oxides of nitrogen (NOx), and smoke emissions are analyzed for emission characterization. The simulation results show that the injection angle and injection pressure influence in-cylinder mixture formation and hydrogen accumulation in the intake manifold. A combination of injection angle = 60 deg and injection pressure = 150 kPa offers good mixture formation. Experimental results show that at 20% hydrogen enrichment, exergy efficiencies of the dual fuel engine are increased from 8.4% to 10.1% at low load and 23.3% to 25.5% at high load. However, maximum reductions in HC and CO emissions of 35.6% and 50.0%, respectively, are calculated at low loadItem A renewable pathway towards increased utilization of hydrogen in diesel engines(Elsevier, 2020-02) Verma, SaketIn the present work, dual fuel operation of a diesel engine has been experimentally investigated using biodiesel and hydrogen as the test fuels. Jatropha Curcas biodiesel is used as the pilot fuel, which is directly injected in the combustion chamber using conventional diesel injector. The main fuel (hydrogen) is injected in the intake manifold using a hydrogen injector and electronic control unit. In dual fuel mode, engine operations are studied at varying engine loads at the maximum pilot fuel substitution conditions. The engine performance parameters such as maximum pilot fuel substitution, brake thermal efficiency and brake specific energy consumption are investigated. On emission side, oxides of nitrogen, hydrocarbon, carbon monoxide and smoke emissions are analysed. Based on the results, it is found that biodiesel-hydrogen dual fuel engine could utilize up to 80.7% and 24.5% hydrogen (by energy share) at low and high loads respectively along with improved brake thermal efficiency. Furthermore, hydrocarbon, carbon monoxide and smoke emissions are significantly reduced compared to single fuel diesel engine operation. Exhaust gas recirculation (EGR) has also been studied with biodiesel-hydrogen dual fuel engine operations. It is found that EGR could improve the utilization of hydrogen in dual fuel engine, especially at the high loads. The effect of EGR is also found to reduce high nitrogen oxide emissions from the dual fuel engine and brake thermal efficiency is not significantly affected.Item Energy Farming—A Green Solution for Indian Cement Industry(Springer, 2020-10) Soni, Manoj KumarCement sector in India is playing an important role in overall development and infrastructure. Coal is the main fuel for the manufacture of cement in India, given the high cost and inadequate availability of oil and gas. Another fuel required to operate the cement plant is diesel. It is required for drilling machine (in mines for blasting), for earth moving machines and in clinker production process for diesel generator to generate emergency power, kiln initial light up, various material handling vehicles, etc. Lot of research is being done to reduce coal consumption in cement plant by replacing the coal through alternative fuels like shredded tyre chips, plastic waste, refused derived fuel (RDF) from MSW, agrowaste, etc. Research for reducing the energy consumption is also in advance stage where Bureau of Energy Efficiency (BEE) has made the scheme for Mandatory Energy Audit of cement plants. Cement industry still has not focused on saving of diesel consumption as the consumption of diesel is less as compared to main fuel (Coal). However, it is well relevant to specify here the rise in diesel cost in India in last five years is alarming for the cement industry. This paper highlights the saving in diesel cost by introducing energy farming (EF) concept in place of green belt area which is statuary requirement for obtaining environmental clearance for cement plant and mines area.Item Comparative Study Using Life Cycle Approach for the Biodiesel Production from Microalgae Grown in Wastewater and Fresh Water(Elsevier, 2018) Sangwan, Kuldip Singh; Raghuvanshi, SmitaUse of bio fuels is a sustainable solution in the current energy scenario, which is marked by unsustainable use of fossil fuels. Production of biodiesel requires microalgae as feedstock. The micro algae require nutrients, CO2 & light source for its growth. An approach where waste water treatment plant can act as source of nutrients for the growth of microalgae would be beneficial. Hence the present work was carried out to understand the life cycle assessment of biodiesel production from microalgae grown in waste water and associated impacts compared with biodiesel production from fresh water. The system boundary considered in the process includes cultivation of microalgae, flocculation, centrifugation, extraction, and transesterification. The functional unit considered for the study is 1 MJ of energy produced from biodiesel. The life cycle assessments (LCA) for the present case was carried out using Umberto NXT software and inventory was taken from Eco invent database v3.0 and literature. Results has shown that the microalgae grown in waste water requires lesser energy as compared to algae grown in fresh water.Item Developments and challenges in biodiesel production from microalgae: A review(2015-07-14) Shukla, Paritosh; Mehrotra, Sandhya Amol; Mehrotra, RajeshThe imminent depletion of fossil fuels and the surging global demand for renewable energy have led to the search for nonconventional energy sources. After a few decades of trial and error, the world is now testing the sources of the third generation of fossil fuels, which contain for most parts microalgae. With more than 80% oil content, being adaptable in growth parameters and highly versatile, microalgae are highly promising sources of biofuels in the present time. The present article makes a sweeping attempt to highlight the various methods employed for cultivation of microalgae, techniques to harvest and extract biomass from huge algal cultures, as well as their downstream production and processing procedures. The advantages, limitations, and challenges faced by each of them have been described to some extent. Major concerns pertaining to biofuels are supposed to be their environmental sustainability and economic viability along with their cost effectiveness. This would require a great deal of empirical data on existing systems and a great deal of optimization to generate a more robust one. We have concluded our article with a SWOT analysis of using algae for biodiesel production in a tabulated form.Item Carbon dioxide to bio-fuels by mixed and pure microbial cultures isolated from activated sludge: relative evaluation of CO2 fixation, biodiesel production, and thermodynamic analysis(Wiley, 2019-08-31) Gupta, Suresh; Raghuvanshi, Smita; Mishra, SomeshIn the present work, the CO2(g) bio-mitigation potential (15% [v/v]) of a mixed microbial population, Enterobacter cloacae and Pseudomonas putida, is thermodynamically assessed and compared at different Fe(II) concentrations (energy source). CO2(g) removal efficiency values are evaluated on per-day basis for all cultures and found maximum for the mixed microbial population. Approximate material balance and thermodynamic assessment of the CO2(g) bio-mitigation studies have revealed that among all cultures, the mixed microbial population shows the highest actual CO2 utilization efficiency (R.RCO2) of 57.67 (±0.04)%. Leachate (biomass + cell free supernatant) obtained from CO2 bio-mitigation batch studies were analyzed using FTIR and gas chromatography–mass spectroscopy. The results obtained have shown the presence of fatty acids and hydrocarbons in considerable amounts. The fatty acids obtained from cultures have shown the presence of a carbon chain length in the range of C7–C25, which makes it a potential source of biodiesel. Biodiesel yields of 91.55%, 77.49%, and 38.69% were obtained for the mixed microbial population, E. cloacae and P. putida. The hydrocarbons obtained from all the microbial cultures were found to have a carbon chain length in the range of C9–C32 and comprised saturated and unsaturated groups, which make them comparable to light oil.Item Lipase Immobilization Techniques for Biodiesel Production: An Overview(IBIMA, 2014-05-13) Bhagavatula, Vani; Mehrotra, Rajesh; Mehrotra, SandhyaThe growing energy needs and depleting fuel sources compel us to look towards production of biodiesel, an appropriate alternative. The industrially used chemical catalysis process is beset with problems that enzymatic production using lipases could avoid. In this light, the immobilization of lipases plays an important role in the optimization of the production process. This review discusses the various techniques that have been studied for lipase immobilization, namely adsorption, covalent attachment, entrapment, cross-linked enzyme agglomerates and whole-cell biocatalysts, while highlighting their benefits and drawbacks. It also sheds light on the future of enzyme immobilization and its industrial application.Item The static extraction of lipid from microalgae Desmodesmus sp. MCC34(WRA, 2016) Verma, Sanjay KumarThe commonly used techniques for extraction of lipids from dry or wet biomass involve energy intensive steps such as cell lysis, high temperature and cell mixing causing substantial energy burden on the process. In present work, we report our finding on using a static method of mixing standard solvent with dry algal biomass without stirring. This extraction procedure was found to depend on the ratio of solvent volume to the biomass (SBR) and surface area factor (SAF). The kinetic study suggests that the static extraction followed Patricelli model of bi-phasic lipid extraction, consisting of a rapid washing step followed by the diffusion step. The results also suggest that the rate of lipid extraction in static process at optimum SBR and SAF, matched the rate of extraction obtained when lysed biomass was used or in the case where biomass was mixed (stirred) with solvent.