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Aims and Scope
Editorial Board

1. Life cycle analysis and environmental effect of electric vehicles market evolution in Portugal

João P. Ribau, Ana F. Ferreira

LAETA, IDMEC, Instituto Superior Técnico, Universidade de Lisboa, 6 Av. Rovisco Pais, 1, 71049-001 Lisboa, Portugal.

Abstract: Fossil fuel dependency in Portugal is represented in around 76% of the total primary energy use, from which almost half is associated to the road transport sector. The reduction of imported fossil energy, pollutants and CO₂ emissions is seen as a solution to a more sustainable energy system. This paper analyzes the market penetration of battery electric vehicles in the road transport sector as an alternative and more efficient technology, considering its maximum share in the transport sector in 2050. The main goal is to evaluate the energy consumption, air pollutants (including CO₂ emissions), and the economic impacts of conventional and electric vehicles in Portugal. The environmental Kuznets effect in the studied factors is also evaluated. Life cycle methodology was applied to the “fuel” production and use stage, and to the materials of the vehicle. Although reducing energy consumption and emissions is essential, the relation of such impact within the region economy is also extremely important. Based on a Kuznets curve hypothesis, some of those impacts were possible to co-relate with the gross domestic product evolution in Portugal. The evolution of the energy source share, energy production efficiency, vehicle type share in the Portuguese light duty vehicle fleet, and technology efficiency, was also considered. Although the electrification of the road sector can potentially lower the fossil fuel importation, the electricity demand should increase. Nevertheless, it is estimated that around 43% of the energy consumption, 47% of CO₂ emissions, and 17%-40% of air pollutants could be reduced with the expected electric vehicle evolution.

Volume 5, Issue 5, 2014, pp.535-558.

2. Use of sugarcane straw ash for zeolite synthesis

Denise Alves Fungaro, Thais Vitória da Silva Reis

Instituto de Pesquisas Energéticas e Nucleares, IPEN–CNEN/SP- Av. Prof. Lineu Prestes, 2242, Cidade Universitária, CEP 05508-000 São Paulo SP, Brasil.

Abstract: The amount of biomass combustion residue is growing nowadays due to constant increasing demands of biomass utilization. The biomass ash produced currently is disposed on agricultural fields. The presence of metals, chlorine, sulphur and other species may have significant impacts on soils and the recycling of soil nutrient. The main challenge is related to the increase of possible applications of this byproduct. Sugarcane straw ash (SCSA) was used in a study on synthesis of zeolitic material by alkaline conventional hydrothermal treatment. Different experimental conditions, such as, reaction time, alkali hydroxide concentration and liquid/solid ratio were studied. Raw ash material and synthesis products were characterized by X-Ray Fluorescence, Fourier transform infrared spectroscopy powder, X-ray diffraction, cation exchange capacity and scanning electron microscopic. The presence of zeolite hydroxysodalite confirms successful conversion of native SCSA into zeolitic material. Sugarcane straw ash utilization minimizes the environmental impact of disposal problems and further appears as an alternative for the future sustainable large-scale management of biomass ash.

3. An experimental study of temperatures in cloud from release of flashing liquid CO₂ in 3m long channel

Amrit Adhikari, André V. Gaathaug, Dag Bjerketvedt, Knut Vaagsaether

Telemark University College, Porsgrunn, Norway.

Abstract: Flashing of the liquid CO₂ is an accidental hazards that may occurs in many industrial sector such as, process industries, carbon capture and storage projects, crude oil extraction process etc. Sometimes the accidental release of liquid CO₂ that causes the health hazards which may costs loss of lives and properties. In order to alleviate the aforementioned probable hazards, the experiment will be highly beneficial. This research activity is conducted through the temperature measurement in the cloud of flashing liquid CO₂ confirming the formation of dry ice and measuring frontal velocity of the cloud as well as its height formed from the vapour CO₂ dispersion. The liquid CO₂ was released in the 3m long channel from the cylinder through two nozzles of diameter 0.5mm and 1.0mm. This leads the formation of dry ice measuring -73^oC and -71^oC from the nozzle sized 0.5mm and 1.0mm respectively. 0.5mm nozzle and 1.0mm nozzle having mass flow rate of liquid CO₂ as 0.0089 kg/s and 0.029 kg/s, overall frontal velocity of 0.52 m/s and 1.51 m/s thus formed cloud height measuring 0.05m and 0.1m respectively. Frontal velocity of the cloud was found to be highest at distance of 0.5m from nozzle with 1.49 m/s and 5.5 m/s for both nozzles 0.5mm and 1.0mm diameter respectively. Upon the increasing distance from the nozzle, the temperature of the formed cloud was seen to be in increasing order.

4. Process simulation of oxy-combustion for maximization of energy output using ASPEN plus

Subhodeep Banerjee, Xiao Zhang, Suraj K. Puvvada, Ramesh K. Agarwal

Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, 1 Brookings Drive, St. Louis, MO 63130, USA.

Abstract: Oxy-fuel combustion is a next-generation combustion technology that shows promise to address the need of low-cost carbon capture from fossil fueled power plants. Oxy-fuel combustion requires expensive pre-processing in an air separation unit to separate pure oxygen from air for the combustion process, which reduces the overall efficiency of the process. This paper employs ASPEN Plus process simulation software to model a simple oxy-fuel combustor and investigates the effect of various parameters on the energy output. The composition of the flue gas is carefully examined. The results of this study provide a starting point for optimized oxy-fuel combustion operation for maximum energy output, which will be crucial for future deployment of oxy-fuel combustion technology.

5. Natural convection mass transfer hydromagnetic flow past an oscillating porous plate with heat source in a porous medium

S. S. Das¹, S. Mishra², P. Tripathy³

1 Department of Physics, KBDAV College, Nirakarpur, Khurda-752 019(Odisha), India.

2 Department of Physics, Christ College, Mission Road, Cuttack-753 001(Odisha), India.

3 Department of Physics, Centurion University, Paralakhemundi, Gajapati-761 211(Odisha), India.

Abstract: This paper analyzes the effect of mass transfer on natural convection hydromagnetic flow of a viscous incompressible fluid through a porous medium past an oscillating porous plate in a porous medium with heat source. The governing equations of the flow field are solved analytically and the expressions for velocity and temperature of the flow field, skin friction t and the heat flux in terms of Nusselts number Nu are obtained. The effects of the important flow parameters such as magnetic parameter M, permeability parameter Kp, Grashof number for heat and mass transfer Gr, Gc, Schmidt number Sc, heat source parameter S and the Prandtl number Pr on the velocity and temperature of the flow field are to be discussed with the help of figures. It is observed that a growing magnetic parameter M retards the magnitude of the velocity of the flow field at all points due to the action of the Lorentz force on the flow field. The heat source parameter S has an accelerating effect on the magnitude of the velocity of the flow field at all points. The effect of growing Grashof number for mass transfer Gc and the permeability parameter Kp is to enhance the velocity (absolute value) of the flow field at all points. An increase in Schmidt number Sc is to increase the magnitude of the velocity of the flow field at all points. A growing rarefaction parameter R enhances the magnitude of the velocity of the flow field at all points.

6. Assessment of anaerobic co-digestion of agro wastes for biogas recovery: A bench scale application to date palm wastes

Zainab Ziad Ismail, Ali Raad Talib

Department of Environmental Engineering, Baghdad University, Baghdad, Iraq.

Abstract: Anaerobic digestion is a technology widely used for treatment of organic waste to enhance biogas recovery. In this study, recycling of date palm wastes (DPWs) was examined as a source for biogas production. The effects of inoculum addition, pretreatment of substrate, and temperature on the biogas production were investigated in batch mode digesters. Results revealed that the effect of inoculum addition was more significant than alkaline pretreatment of raw waste materials. The biogas recovery from inoculated DPWs exceeds its production from DPWs without inoculation by approximately 140% at mesophilic conditions. Whereby, the increase of biogas recovery from pretreated DPWs was 52% higher than its production from untreated DPWs at mesophilic conditions. The thermophilic conditions improved the biogas yield by approximately 23%. The kinetic of bio-digestion process was well described by modified Gompertz model and the experimental and predicted values of biogas production were fitted well with correlation coefficient values > 0.96 suggesting favorable conditions of the process.

7. Effect of heat transfer law on the finite-time exergoeconomic performance of a generalized irreversible carnot heat engine

Yi Zhang¹,  Lingeng Chen^2,3,4, Guozhong Chai¹

1 College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China.

2 Institute of Thermal Science and Power Engineering, Naval University of Engineering, Wuhan 430033, China.

3 Military Key Laboratory for Naval Ship Power Engineering, Naval University of Engineering, Wuhan 430033, China.

4 College of Power Engineering, Naval University of Engineering, Wuhan 430033, China.

Abstract: The analytical expression for profit rate of a generalized irreversible Carnot heat engine cycle based on a generalized radiative heat transfer lawis derived by applying the finite time exergoeconomic method, taking into account several additional irreversibilities, such as heat resistance, heat leakage and other undesirable irreversible factors. The compromise optimization between economics (profit rate) and the efficiency was obtained by searching the efficiency at maximum profit rate, which is termed as the finite time exergoeconomic performance bound.

8. Phisical and chemical properties and thermobaric conditions of occurrence of hard-to-recover oils

I.G. Yashchenko, Y.M. Polishchuk

Institute of Petroleum Chemistry, Siberian Branch of Russian Academy of Sciences, 4, Akademichesky Ave., 634021, Tomsk, Russia.

Abstract: The criteria necessary to classify oils as hard-to-recover oil reserves are determined. The distribution of viscosity, heavy, paraffin and highly resin oils is analyzed in terms of their reserves. The features of the physic-chemical properties of these oils are studied under various conditions of their occurrence and formation temperatures. The results obtained could be used to solve practical issues in the oil sector.

9. Simulating an ocean wave power plant with Homer

Jones S. Silva, Alexandre Beluco, Luiz Emílio B. de Almeida

Inst Pesquisas Hidráulicas, Univ Fed Rio Grande do Sul, Porto Alegre, Brazil.

Abstract: In recent years, renewable resources have become an important alternative to increase the capacity of power generation. Among the resources available, the energy in the oceans have attracted more interest and experiencing a period of strong development. Wave energy is the one that is currently closest to reach a stage of technical and economic maturity. In this process, computational tools to facilitate evaluation of the feasibility of power systems including ocean wave power plants are critical. This paper presents the use of software Homer, version Legacy, for evaluation of technical and economic feasibility of hybrid energy systems including contribution of wave energy. Homer is a software designed for the optimization of micro power systems that has a very broad spectrum of applications. A case study in southern Brazil is presented, studying the inclusion of an ocean wave power plant in a wind biodiesel hybrid system and showing the functionality of Homer for this purpose.

10. Improve of produced gas quality by using air/steam in fluidized bed gasifier

Salami N, Skala Z

Energy institute, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno, Czech Republic.

Abstract: The aim of this work is to determine the best operating parameters of system air- steam gasification in in fluidized bed gasifier,which achive the best gas quality. To accomplish this task, many experiments have been performed to study the effect of reactor temperature(T101), steam to biomass ratio (S/B) and temperature of provided steam (Tf1), low heating value(LHV), gas yield, carbon conversion efficiency and gasifier efficiency.