Rahul Singh Chutia

Perennial grass (Arundo donax L.) as a feedstock for thermo-chemical conversion to energy and materials

In the present study, perennial grass species Arundo donax L. was pyrolysed in a fixed-bed reactor and characterization was performed for the liquid and the solid products. The effect of process parameters such as temperature (350-650 °C), heating rate (10 °C and 40 °C min(-1)) and sweeping gas flow rate (50-250 ml min(-1)) was also investigated. Maximum bio-oil yield of ∼ 26% was observed at 500 °C for the heating rate of 40 °C min(-1). Chemical composition of the bio-oil was analysed through NMR, FTIR and GC-MS. The biochar was characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy along with elemental analysis (CHN). The biochar produced as a co-product of A. donax pyrolysis can be a potential soil amendment with multiple benefits including increased soil fertility and C-sequestration. Current investigation suggests suitability of A. donax as a potential feedstock for exploitation of energy and biomaterials through pyrolytic route.

Pyrolysis of Mesua ferrea and Pongamia glabra seed cover: Characterization of bio-oil and its sub-fractions

In the present study, pyrolysis of Mesua ferrea seed cover (MFSC) and Pongamia glabra seed cover (PGSC) was performed to investigate the characteristics of bio-oil and its sub fractions. In a fixed bed reactor, the effect of temperature (range of 350-650 °C) on product yield and quality of solid product were monitored. The maximum bio-oil yield of 28.5 wt.% and 29.6 wt.% for PGSC and MFSC respectively was obtained at 550 °C at heating rate of 40 °C/min. The chemical composition of bio-oil and its sub fractions were investigated using FTIR and (1)H NMR. GC-MS was performed for both PGSC and MFSC bio-oils and their corresponding n-hexane fractions. The results showed that bio-oil from the feedstocks and its sub-fractions might be a potential source of renewable fuel and value added chemicals.

Thermogravimetric and decomposition kinetic studies of Mesua ferrea L. deoiled cake

The present study aims to explore the physico-chemical properties of Mesua ferrea L. (Iron wood tree) deoiled cake (MFDC) and decomposition parameters for thermochemical methods of conversion. The physico-chemical characteristics of MFDC were investigated by bomb calorimetry, TG/DTA (10, 20 and 40°C min(-1)), elemental analysis (CHN) and FTIR spectroscopy. The proximate composition was calculated using standard ASTM methodology. The temperature profile, activation energy (E), pre-exponential factor (A) and reaction order (n) for the active pyrolysis zone of the species under investigation have been provided for the respective heating rates using Arrhenius, Coats-Redfern, Flynn-Wall-Ozawa (FWO) and Global independent reactions model. The current investigation suggests that within the realm of existing biomass conversion technologies, MFDC can be used as a feedstock for thermochemical conversion.

Characterization of liquid and solid product from pyrolysis of Pongamia glabra deoiled cake.

In the present study, a new feedstock, Pongamia glabra deoiled cake (PGDC), is reported for pyrolysis. Experiments were conducted in a laboratory scale fixed-bed pyrolyzer at temperatures ranging from 350 to 600°C with varying heating rates of 10, 20, 40°C/min in nitrogen atmosphere. The highest liquid yield of 30.60% was observed at 500°C with heating rate of 40°Cmin(-1). The biochar obtained had a porous structure and was characterized by powder X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy along with elemental analysis. The representative bio-oil sample was characterized by CHN analyzer, GC-MS, NMR and FTIR spectroscopy. The bio-oil has a calorific value of 28.19MJ/kg and contains a higher amount of aliphatic compounds. The present investigation suggests that within the realm of biomass energy conversion technologies the PGDC can be used as a feedstock for pyrolysis conversion, thereby serving the demand of second generation biofuels.

Complete utilization of non-edible oil seeds of Cascabela thevetia through a cascade of approaches for biofuel and by-products

Lipid-rich biomass, generally opted for biodiesel production, produces a substantial amount of by-product (de-oiled cake and seed cover) during the process. Complete utilization of Cascabela thevetia seeds for biofuel production through both chemical and thermochemical conversion route is investigated in the present study. Various properties of biodiesel produced was characterized and compared with those obtained from similar oil seeds. The by-products of the chemical process were used as a feedstock for pyrolysis at different temperatures in a fixed bed reactor. Maximum bio-oil yields of 29.11% and 26.18% were observed at 500°C. The bio-oil obtained at optimum yield was characterized by CHN analyzer, NMR and FTIR spectroscopy. The biochar produced was further characterized by SEM-EDX, XRD and FTIR along with elemental analysis to explore its utilization for various purposes. The present investigation depicts a new approach towards complete utilization of lipid-rich bio-resources to different types of biofuels and biochar.

Exploitation of Pongamia glabra deoiled cake for alternate energy: Physico-chemical characterization and thermogravimetric studies

ABSTRACT Utilization of agro-wastes for biofuel generation has been accepted as one of the feasible means for curbing down mankind’s dependence on conventional petro fuels. In this regard, the present investigation aims to understand the properties of Pongamia glabra deoiled cake (a byproduct of the biodiesel production process) for biofuel production. The deoiled cake was investigated for its physico-chemical characteristics by Bomb calorimetry, TG analysis (10, 20, and 40° min–1), CHN analysis, and Fourier transform infrared spectroscopy. The proximate composition was calculated using standard ASTM methodology. The temperature characteristics, activation energy, pre-exponential factor, and reaction order for the active pyrolysis zone of the species under investigation have been provided for the respective heating rates using Arrhenius, Coats–Redfern, and Flynn–Wall–Ozawa methods. The findings suggest feasibility of liquid fuel production from Pongamia glabra deoiled cake via thermochemical conversion.

Feedstock Suitability for Thermochemical Processes

Biomass resources and their utilization offer a new paradigm of research in the changing world faced with diverse problems related to fossil fuel use for most of the energy needs of the society. This chapter discusses the unique characteristics of various biomass resources with varied composition and properties. Thermochemical biomass conversion methods offer greater flexibility in terms of usability of almost all types of biomass as feedstock and end product for further conversion to fuels and chemicals. However, thermochemical conversion efficiency is an area requiring attention from researchers, as certain biomass constituents and their inherent properties pose technological challenges during conversion. Various ways to mitigate these problems are being researched and are discussed in this chapter.

Biohydrogen Production Scenario for Asian Countries

Despite continuous advancement in energy technologies, the greenhouse gas and pollutant emission due to combustion of fossil fuel is increasing day by day due to its growing demand. With the growing worldwide concern regarding increasing global climate change and depleting energy source, it has become the necessity of the hour to generate fuel with safer, efficient, economic, and reasonably environmental-friendly technology. To address this issue, a variety of efficient end-use technologies and alternative fuels have been proposed; this includes compressed natural gas; reformulated gasoline or diesel; methanol; ethanol; synthetic liquids from natural gas, biomass, or coal; and hydrogen. In this regard hydrogen has emerged as a promising option since it offers to solve various important societal impacts of fuel use at the same time. Hydrogen (H2) produced through wastewater treatment using biological routes (dark and photo-fermentation) can be considered as a renewable and sustainable resource. Negative-valued wastewater contains high levels of biodegradable organic material with net positive energy and minimizes the economics of H2 production and treatment cost. This chapter mainly focuses on the global biohydrogen research trend specifically in Asian countries. Bibliometric and scientometric analysis performed with ISI Web of Knowledge [Thomson Reuters] documented significant increments in publications wherein India stands top in biohydrogen production using wastewater. Current status and road map showed that China followed by other Asian countries have significantly contributed towards H2 production. Future perspective suggests for integrative H2 production strategies such as microbial electrolysis, polyhydroxyalkanoate (PHA) production, bioaugmentation, and metabolic engineering to overcome some of the limitations for process scale-up.