Journal of The Energy Institute 

About: Journal of The Energy Institute is an academic journal published by Elsevier BV. The journal publishes majorly in the area(s): Combustion & Chemistry. It has an ISSN identifier of 1743-9671. Over the lifetime, 1587 publications have been published receiving 29180 citations.

Volatile production from pyrolysis of cellulose, hemicellulose and lignin

Abstract: To better understand pyrolysis mechanism and further develop selective pyrolysis technology, characteristics of volatile products in the pyrolysis of three main components (cellulose, hemicellulose and lignin) were investigated and compared by amplifying experiments in a tube furnace at 300–700 °C. Distribution of volatile products (including bio-oil and bio-gas), the influence of temperature and contributions of each single component were discussed in depth. It was found that, for each sample pyrolysis, pyrolysis temperature and their own chemical structures played an important role in the yields, composition of bio-oil and bio-gas. The optimal temperatures for production of bio-oil from cellulose, hemicellulose and lignin focused at 500 °C, 450 °C and 600 °C, respectively, and cellulose made greater contribution to bio-oil formation, and hemiellulose was the major contributor for bio-gas. Moreover, the more bio-gases from the three components generated at the higher temperature, but compositions of volatile products were different depending on their unique chemical structures. In the three components, cellulose produced the highest CO, hemicellulose owned the highest CO2, and lignin generated the highest CH4 characterized by the largest HHV. As for bio-oil, cellulose bio-oil displayed unique saccharides and higher furans, hemicellulose bio-oil contained higher acids and ketones, while phenols were the dominant composition of lignin bio-oil.

A review of the current knowledge and challenges of hydrothermal carbonization for biomass conversion

Abstract: Greenhouse gases emitted from the excessive use of fossil fuels are threatening the environment, and thus alternative resources like biomass are being considered as a replacement. Biomass with high moisture content is better treated by hydrothermal carbonization method than any other process to generate biofuel. Research on this method on a lab scale has progressed recently. However, due to the complex reaction mechanisms and operational barriers, more improvements are required to make it a commercial technology. This paper aims to review the development of hydrothermal carbonization with a focus on the practical aspects of the process. Many references have been reviewed critically to provide a well-structured source for improving this process. After providing information about the biomass structure and general knowledge of hydrothermal carbonization, the challenges faced in attempts to improve the process have been identified as lack of valid kinetic and heat transfer models and insufficient data on continuous and large-scale reactors. Useful and practical suggestions have been presented to tackle all these challenges.

An overview of utilizing water-in-diesel emulsion fuel in diesel engine and its potential research study

Abstract: The need for more efficient energy usage and a less polluted environment are the prominent research areas that are currently being investigated by many researchers worldwide. Water-in-diesel emulsion fuel (W/D) is a promising alternative fuel that could fulfills such requests in that it can improve the combustion efficiency of a diesel engine and reduce harmful exhaust emission, especially nitrogen oxides (NOx) and particulate matter (PM). To date, there have been many W/D emulsion fuel studies, especially regarding performance, emissions and micro-explosion phenomena. This review paper gathers and discusses the recent advances in emulsion fuel studies in respect of the impact of W/D emulsion fuel on the performance and emission of diesel engines, micro-explosion phenomena especially the factors that affecting the onset and strength of micro-explosion process, and proposed potential research area in W/D emulsion fuel study. There is an inconsistency in the results reported from previous studies especially for the thermal efficiency, brake power, torque and specific fuel consumption. However, it is agreed by most of the studies that W/D does result in an improvement in these measurements when the total amount of diesel fuel in the emulsion is compared with that of the neat diesel fuel. NOx and PM exhaust gas emissions are greatly reduced by using the W/D emulsion fuel. Unburnt hydrocarbon (UHC) and carbon monoxide (CO) exhaust emissions are found to be increased by using the W/D emulsion fuel. The inconsistency of the experimental result can be related to the effects of the onset and the strength of the micro-explosion process. The factors that affect these measurements consist of the size of the dispersed water particle, droplet size of the emulsion, water-content in the emulsion, ambient temperature, ambient pressure, type and percentage of surfactant, type of diesel engine and engine operating conditions. Durability testing and developing the fuel production device that requires no/less surfactant are the potential research area that can be explored in future.

A review on various after treatment techniques to reduce NOx emissions in a CI engine

Abstract: NOx emissions have always been a main concern in the development of diesel engines. This paper summarizes the studies about NOx emission reduction in diesel engines. The need for meeting the stringent requirements with regard to NOx emissions in a diesel engine has led to the development of a range of after treatment techniques. After treatment methods are required to reduce NOx emissions that cannot be controlled by fuel composition and combustion phenomena. Current after treatment techniques that are being employed are Selective Catalytic Reduction (SCR), Lean NOx Trap (LNT) and SCR Filter (SCRF). The benefits and constraints of different types of SCR are discussed. Urea SCR is a prominent well proven technology. Urea SCR produces 96–99% conversion efficiency with the help of a reductant NH 3 . The operating parameters such as nature of catalyst, temperature range of catalyst, flow of DEF (Diesel Exhaust fluid) to injector and mixing of NH 3 and NOx are discussed. Hybrid SCR such as Cu-SCR + Fe-SCR, SCR + LNT moderates fuel consumption and augments the catalytic activity at low temperature. SCRF has low cell density (200–300 csi vs 400–600 csi for SCR), and also has lower deNOx efficiency for a number of reasons. Pre-stored NH 3 and Preheating helps in low temperature reaction of SCRF. Technical problems in aqueous urea systems have led to the evolution of solid SCR system (SSCR). This review incorporates the study of solid ammonium salts decomposition, temperature range of the salts and infrastructure required for SSCR.

Comparative studies on the pyrolysis of cellulose, hemicellulose, and lignin based on combined kinetics

Abstract: The thermal degradation behavior and pyrolytic mechanism of cellulose, hemicellulose, and lignin are investigated at different heating rates from 10 Kmin−1 to 100 Kmin−1 with a step-size of 10 Kmin−1 using thermogravimetric analysis (TGA) equipment. It is observed that there are one, two, and three stages of pyrolytic reactions takes place in cellulose, hemicellulose, and lignin respectively. Isoconversional method is not suitable to analyse pyrolysis of hemicellulose and lignin as it involves multi-step reactions. The activation energies of the main decomposition stage for cellulose, hemicellulose, and lignin are 199.66, 95.39, and 174.40 kJ mol−1 respectively. It is deduced that the pyrolysis reaction of cellulose corresponds to random scission mechanism while the pyrolysis reaction of hemicellulose and lignin follows the order based reaction mechanisms.