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This study presents an investigation on the influence of hydrothermally treated municipal solid waste (MSW) on the co-combustion characteristics with different rank coals, i.e. Indian, Indonesian and Australian coals. MSW blends of 10%, 20%, 30% and 50% (wt.%) with different rank coals were tested in a thermogravimetric analyser (TGA) in the temperature range from ambient to 700 °C under the heating rate of 10 °C/min. Combustion characteristics such as volatile release, ignition and burnout were studied for the blend fuel. Different ignition behavior was observed depending on the blends composition and the coal rank. The result of this work indicates that the blending of MSW improves devolatization properties of coal. But it was found that the co-combustion characteristics of MSW and coal blend cannot be predicted only from the pyrolytic and or devolatization phenomena as the other factors such as the coal quality also plays a vital role in deciding the blends co-combustion characteristics. The TGA combustion profiles showed that the combustion characteristics of blends followed those of parent fuels in both an additive and non-additive manners. These experimental results help to understand and predict the behavior of coal and MSW blends in practical applications.

Abstract Some scholars have addressed the relationship between the Human Development Index (HDI) and energy consumption in terms of the semi-logarithmic or hyperbolic function. One of the results from this relationship is to divide the world countries into two categories, developed and developing countries. This classification considers pre-developing countries and developing countries into one category (developing) while the proportion of people with fundamental energy needs in the former is far higher than in the latter. The objective of this paper is to allocate a separate class for pre-developing which their fundamental energy needs have not completely satisfied. The methodology of the study is divided into two parts. Initially, based on the longitudinal data (112 country’s data during the period of 2005–2013), a linear Quality of Life (QoL) indicator is proposed in terms of six variables. Then an S-shape (sigmoid) curve is fitted to the QoL indicator data against energy consumption (total primary energy supply as a proxy) per capita (ECpc) and electricity consumption per capita (Elcpc) data. Three types of countries, developed, developing, and pre-developing are identified based on the sigmoid function. The results of the proposed model demonstrate that the “pre-developing” category has different QoL and ECpc as compared to developing and developed classes. Another result of the paper shows the entry of new technologies has influenced the QoL and Elcpc to a greater extent in developing countries than in developed countries. One-way analysis of variance is a method to shed light on the latter consequence. In the case of pre-developing countries, the pertinent analysis shows an insignificant impact. This paper concludes the new classification of countries appropriately addresses variation of QoL against ECpc in each class.

Abstract One of the strategies to improve environmentally friendly energy harvesting can be realized by using biomass as a primary energy source for generating electricity and H2. In addition, high energy efficiency can be achieved by minimizing exergy loss through process integration and exergy recovery. As an implementation, this study proposes a cogeneration system for black liquor (BL) to co-produce electricity and H2. The system primarily comprises BL drying, circulating fluidized bed gasification, syngas chemical looping (SCL), and power generation. The Aspen Plus V8.8 software package is used for modeling and performing calculations of the proposed integrated system. Furthermore, thermodynamic analysis of gasification is performed by employing Gibbs energy minimization. The effects of target solid content on the required total work and compressor outlet pressure during drying and gasification with different steam-to-fuel ratios are evaluated. Moreover, the SCL process adopts three reactors, namely, the reducer, oxidizer, and combustor. Compared to conventional processes, the integrated drying-gasification-SCL processes are significantly cleaner and more energy efficient. The proposed integrated system can achieve a net energy efficiency of about 70% with almost 100% carbon capture.

Abstract As an alternative to thermoelectric generators, heat engines show great interest thanks to their ability to convert temperature spatial gradient into time-domain temperature variations or vibrations. To this end, MultiPhysic Memory Alloys (MPMAs), combining shape memory characteristics with ferromagnetic properties, provide significant attractive characteristics such as sharp transition with reduced hysteresis as well as magnetic properties enabled by heating, thus allowing easier device development and implementation. In this study, we report the development of a heat engine for small-scale energy harvesting where the MPMA transfers its heat to a pyroelectric element that provides thermal to electrical energy conversion, yielding a more direct energy conversion path compared to conventional electromechanical heat engines. Furthermore, thermally decoupling the pyroelectric element from the MPMA allows a faster cooling of the latter, accounting for higher variation frequency. Compared to the use of electromagnetic transduction through a coil attached to the moving MPMA, this approach is shown to provide 3 to 9 times more power density (according to considered volume), with theoretical potential gains from 8 to 25 with the use of nonlinear electrical interfaces.

Abstract We investigate the prospects of three zero-emission scenarios for achieving the target of limiting global mean temperature rise to 2 °C or below, and compare them with the business-as-usual (BAU) scenario involving no climate policy intervention. The “2100 zero” emissions scenario requires zero emissions after 2100 until 2150. The “350 ppm zero” emissions scenario entails zero emissions in the latter half of this century, which can be achieved by the cumulative emissions constraints of the Wigley–Richels–Edmonds (WRE) 350 from 2010 to 2150. Finally, the “net zero” scenario requires zero cumulative emissions from 2010 to 2150, allowing positive emissions over the coming several decades that would be balanced-out by negative emissions in the latter half of the century. The role of biomass energy carbon capture and storage (BECCS) with forested land is also assessed with these scenarios. The results indicate that the 2 °C target can be achieved in the “net zero” scenario, while the “350 ppm zero” scenario would result in a temperature rise of 2.4 °C. The “2100 zero” scenario achieved a 4.1 °C increase, while the BAU reached about 5.2 °C. BECCS contributed to achieving zero-emission requirements while providing a limited contribution to energy supply. The findings indicate substantial future challenges for the management of forested land.

MgO/H2O/Mg(OH)2 chemical heat storage of waste energy from industrial processes is a promising technology in view of a more efficient use and saving of primary energy sources. A new approach was used to develop a hybrid heat storage material made of magnesium hydroxide (Mg(OH)2) and exfoliated graphite (which is used to improve the heat transfer with its high thermal conductivity). Mg(OH)2 nanoplatelets were directly grown on graphite surface via a deposition–precipitation method to increase the compatibility between the two materials. The material thus obtained, named DP-MG, was experimentally tested to determine its heat storage and output capacities. An improvement of the material efficiency was obtained with a higher storage capacity at lower reaction temperature and a higher heat output rate.

Synthesis of a chemical or energy system is very creative. Only a designer with special skills can accomplish it. Thermodynamics has a hierarchical structure and each level of the structure has its own application to process system synthesis.