Ruprekha Saikia

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.

Effect of torrefaction on yield and quality of pyrolytic products of arecanut husk: An agro-processing wastes

In the present study, arecanut husk, an agro-processing waste of areca plam industry highly prevalent in the north-eastern region of India, was investigated for its suitability as a prospective bioenergy feedstock for thermo-chemical conversion. Pretreatment of areca husk using torrefaction was performed in a fixed bed reactor with varying reaction temperature (200, 225, 250 and 275°C). The torrefied areca husk was subsequently pyrolyzed from temperature range of 300-600°C with heating rate of 40°C/min to obtain biooil and biochar. The torrefied areca husk, pyrolysis products were characterized by using different techniques. The energy and mass yield of torrefied biomass were found to be decreased with an increase in the torrefaction temperature. Further, biochar were found to be effective in removal of As (V) from aqueous solutions but efficiency of removal was better in case of torrefied biochar. Chemical composition of bio-oil is also influenced by torrefaction process.

Pyrolysis and kinetic analyses of a perennial grass (Saccharum ravannae L.) from north-east India: Optimization through response surface methodology and product characterization

The objective of the present investigation was to optimize the pyrolysis condition of an abundantly available and low cost perennial grass of north-east India Saccharum ravannae L. (S. ravannae) using response surface methodology based on central composite design. Kinetic study of the biomass was conducted at four different heating rates of 10, 20, 40 and 60 °C min-1 and results were interpreted by Friedman, Kissinger Akira Sunnose and Flynn-Wall-Ozawa methods. Average activation energy 151.45 kJ mol-1 was used for evaluation of reaction mechanism following Criado master plot. Maximum bio-oil yield of 38.1 wt% was obtained at pyrolysis temperature of 550 °C, heating rate of 20 °C min-1 and nitrogen flow rate of 226 mL min-1. Study on bio-oil quality revealed higher content of hydrocarbon, antioxidant property, total phenolic content and metal chelating capacity. These opened up probable applications of S. ravannae bio-oil in different fields including fuel, food industry and biomedical domain.

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.

Waste Valorization to Fuel and Chemicals Through Pyrolysis: Technology, Feedstock, Products, and Economic Analysis

The decreasing fossil fuel reserves, rise in oil prices, and increasing awareness of environmental impact of continued fossil fuel use have made the quest for alternative energy sources significant throughout the world. In this regard, conversion of various types of wastes to biofuels and biomaterials offers a new paradigm of research in the changing world faced with these diverse problems. Lignocellulosic biomasses are the most predominant among different types of waste resources and are characterized by diverse nature and abundant supply. However, it also has numerous competitive uses which shrink the biomass resource base for energy production. There are numerous biomass materials which are produced as by-products, residues, or wastes from other processes, operations, or industries. The energy content of these materials can be usefully exploited and have the advantage of removing these materials from the landfill. This chapter presents an overview of the pyrolytic conversion of low-value biomass/bio-wastes, agricultural residues, bioenergy by-product, industrial agro-wastes, aquatic wastes, MSW, plastic solid wastes to bio-oil and biochar and their wide-ranging applications. Further, this chapter also reviews the pyrolysis technology and its economic analysis.

Sidestreams From Bioenergy and Biorefinery Complexes as a Resource for Circular Bioeconomy

One of the main drivers for the establishment of biorefineries and the drive toward bioeconomy is the call for sustainability. However, the modern-day biorefinery must embrace on the concept of who ...

An Assessment on Indian Government Initiatives and Policies for the Promotion of Biofuels Implementation, and Commercialization Through Private Investments

Energy has emerged as one of the most critical issues governing the economic, political, environmental, and social development of countries directly or indirectly. Availability of clean, efficient, affordable, and reliable energy is at the center of global prosperity and sustainable development. For developing counties like India, expanded access to dependable and modern energy service is a must for their fight against poverty and low living conditions of their citizens, while meeting objectives like increasing productivity, growing competitiveness, and improving economic growth at the same time.

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.

Biomass Resources for Biofuel Production in Northeast India

India’s overwhelming economic growth rate of 8 % on an average creates a huge demand for energy inputs. The swelling energy consumption has resulted in growing dependence on fossil fuels, which has in turn raised a gamut of concerns like energy security, environmental degradation, and pressure on national exchequer. Energy conservation and clean and C-neutral fuels in this regard offer the greatest opportunities. Biomass-based renewable energy has the proven potential in this direction. Since India has an agricultural-based economy, therefore, biomass– including wood, agricultural residues, animal dung, etc. – is available in enormous quantities. In India, about 40 % of the total energy requirement comes from burning of biomass, and more than 70 % of the population depends on it for energy requirements. The northeast region of India where traditional biomass is a predominant source of energy is no exception to this. However, burning of biomass has been associated with energy inefficiency and environmental hazards including health problems and deforestation. Therefore, a sustainable approach toward this end is adoption of custom-made technological intervention to use the enormous biomass resource and generate power in an environment-friendly and cost-effective scheme. Biomass-based energy and power production can provide distributed power for rural applications and could effectively make up for the absence of grid electricity supply in many remote areas. Besides, tail-end grid-connected power projects are also currently highly encouraged to support the Renewable Energy Purchase Obligation and its compliance under the Electricity Act, 2003. This chapter reviews the biomass availability, conversion technologies, and its biofuel production potential in the northeastern region of India which is known for its high biological biodiversity with numerous tropical rainforests, revering grasslands, bamboo, orchards and wetland ecosystems.