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This study focused on developing a new cocktail extraction agent (CEA) composed of solvent and a new surfactant material (SM) for enhancing the efficiency of fuel recovery from real waste oil sludge (WSO). The effects of different solvents (e.g. methyl ethyl ketone (MEK), naphtha, petrol and kerosene), SMs (Dowfax and sodium thiosulfate), extraction time (10–20 min), extraction temperatures (20–60 °C) and CEA/sludge ratios (1–4) on the extraction performance were investigated. SMs and DBBE design enhanced the extraction efficiency by increasing the dispersion of solvent in WSO and enhancing the mixing and mass transfer rates. Results proved that Dowfax was the best SM for oil recovery under various conditions. The best CEA (e.g. MEK and Dowfax) provides the maximum fuel recovery rate of 97% at a period of 20 min, temperature of 60 °C and 4:1 CEA/sludge ratio. The produced fuel was analysed and fed to the distillation process to produce diesel oil. The characteristics of diesel oil were measured, and findings showed that it needs treatment processes prior its use as a finished fuel. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel system for production and storage of H 2 with net-zero carbon emissions is developed. • High-temperature fuel cells and biogas upgrading unit are efficiently integrated. • Waste heat of the fuel cells is recovered in the Cu-Cl unit for hydrogen production. • Integrated process can generate 108 kmol/h liquid hydrogen and 18.88 MW power. • A hybrid method of the GA and artificial intelligence tools is applied for optimization. Global energy consumption has been exponentially increasing, leading to the depletion of conventional energy sources and a considerable increase in greenhouse gas emissions. The exploitation of sustainable energy sources and the development of innovative methods for mitigation of CO 2 emissions is necessary. Hydrogen (H 2) as a versatile and green fuel can be produced and stored in liquid form using sustainable energy sources through innovative methods. In this paper, a novel optimal hybrid structure is proposed for hydrogen production and storage with net-zero CO 2 emissions. A high-temperature fuel cell is utilized to reduce CO 2 emissions and supply the heat and power needed to produce and liquefy hydrogen. The hybrid configuration employs an electro-thermochemical unit for hydrogen production, molten carbonate fuel cells, a hydrogen liquefaction process, and a biogas upgrading by water scrubbing. A robust combination of meta-heuristic algorithms and artificial intelligence is developed to optimize the investment return period and energy/exergy efficiencies. The fuzzy Bellman-Zadeh, LINMAP, and TOPSIS techniques are also used to make decisions in multi-objective optimization. This innovative configuration generates 108 kmol/h liquid hydrogen, 18.88 MW power, 54 kmol/h oxygen, and 3258 kmol/h hot water. Pinch, sensitivity, exergy, and economic assessments are implemented to evaluate the performance of the hybrid structure. The thermal and exergy efficiencies of the proposed configuration are obtained to be 78.21 % and 64.83 %, respectively. The greatest portions of destructed exergy are resulted from the fuel cells-gas turbine hybrid system (63.63 %), electro-thermochemical unit (25.96 %), and biogas upgrading technology (6.23 %). The returns period on investment, the prime price of electricity, and the net benefit are computed as 4.854 years, 0.0420 US$/kWh, and 15.73 million US$/years, respectively, based on the energy potentials of Newfoundland and Labrador, Canada. [ABSTRACT FROM AUTHOR]

Increasing demand for energy and also escalating environmental pollution show that industries cannot rely on fossil fuels, and it is necessary to adopt an alternative. In recent decades, algal bioenergy has emerged as a renewable energy source in different industries. However, algal bioenergy production is costly and faces different challenges (technical and non-technical) and unknown aspects that need to be addressed. Experimental and theoretical research works have revealed that the efficiency of algal bioenergy production is influenced by several factors, including algae species, temperature, light, CO 2 , cultivation method, and available nutrients. Algal bioenergy production on commercial scales in cost-effective ways is the main aim of industries to compete with fossil fuels. Hence, it is vital to obtain a comprehensive knowledge of the previous findings and select a suitable pathway for future studies/activities. In the present review paper, the potential of microalgae bioenergy production, influential parameters, previous experimental and theoretical studies, and different methods for microalgae biofuel production from cultivation stage to utilization are reviewed. Moreover, this work discusses the engineering activities and economic analysis of microalgae cultivation to utilization. Useful suggestions are also made for future research investigations. The outcomes of the present work confirm that innovative engineering methods can overcome scale-up challenges, increase the rate of production, and decrease the cost of algae bioenergy production. Hence, there is no long way to produce cost-effective algae bioenergy on commercial scales. [Display omitted] • Types, properties, and potential of microalgae for bioenergy production and utilization are summarized. • The influential factors in algae bioenergy production processes are highlighted. • The use of wastewater for microalgae production can decrease the total costs. • Possible strategies for increasing microalgae production (e.g., genetic engineering) are addressed. • Challenges in research/engineering activities and possible solutions in algae bioenergy area are listed. [ABSTRACT FROM AUTHOR]

Accurate determination of bubble pressure of reservoir fluid at reservoir conditions is one of the important parameter which is necessary for various calculations in petroleum engineering. This study presents two improved algorithms based on machine learning approaches for efficient estimation of saturation pressure of reservoir oil. To achieve the research purpose, a large data set, comprising of more than 750 crude oil samples with different composition and geographical origins, was collected from the literature for development of the models. The efficiency of the proposed models was tested against sixteen well-known empirical correlations. The proposed models show good performance in terms of accuracy with the lowest error percentage and highest R2 values. A large experimental data bank was compiled for the development of the models. The developed models are more accurate than all other published correlations. [ABSTRACT FROM AUTHOR]

Abstract: Australia has considerable hot rock geothermal energy potential. This results from the widespread occurrence of basement rocks (granites in particular) in which heat is generated by natural radioactive decay. There are extensive areas where temperatures are estimated to reach at least 200°C at around 5km depth. In Australia, there is also potential for lower temperature geothermal resources associated with naturally-circulating waters in aquifers deep in a number of sedimentary basins (Hot Sedimentary Aquifer Geothermal). These are potentially suitable for electricity generation and direct use. This paper will focus on the need to improve geothermal energy utilization in Australia, challenges facing it and the future benefits. This study shows, there is a significant potential for energy savings through greater use of geothermal energy in some regions of Australia. [Copyright &y& Elsevier]

• Homogeneous and heterogeneous catalysts in biodiesel production are reviewed. • Transesterification reactors are used in manufacturing of biodiesel. • The impacts of key parameters on performance of transesterification process are examined. • Advantages and disadvantages of each reactor technology for biodiesel production are outlined. • Sustainability aspects of biodiesel production methods are comprehensively discussed. There is no sustainability to fossil fuels. Consequently, energy from renewable sources should meet present-day and future demand. Fossil fuel consumption has consistently influenced and harmed the environment, prompting the development of renewable and clean fuels such as biodiesel. Biodiesel production primarily involves the transesterification process, which consists of key components, namely, the feedstock, catalyst, reaction, and product separation or purification stages. It is imperative to acknowledge the emergence of innovative technologies with significant potential for biodiesel synthesis to attain a commercially viable and efficient biodiesel production process. Recently, researchers have investigated biodiesel reactors' effectiveness in energy and time efficiency in producing biodiesel. This review comprehensively assess the key technical aspects of each reactor in order to learn more about their mechanisms and pick the best reactor technology for the transesterification procedure. Various transesterification reactors, such as plug-flow, microwave, and simultaneous reaction-separation, are then examined from scientific and practical perspectives. This research aims to elucidate the merits, limitations, advantages, and disadvantages of various reactor technologies employed in biodiesel synthesis. Furthermore, it discusses the benefits, challenges, and future prospects of biodiesel. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: As concerns about rising fossil fuel prices, energy security, and climate change increase, renewable energy can play a key role in producing local, clean, and inexhaustible energy to supply Australia’s growing demand for electricity, heat, and transportation fuel. Renewable energy is an essential part of Australia’s low emissions energy mix and this energy is important to its energy security. Australia has some of the best renewable energy resources in the world. This paper will focus on the impact of these renewable energies in Australia. This study shows that Australia has the potential to secure its long term energy future through focus and encouragement on increasing utilisation of renewable energy. [Copyright &y& Elsevier]

[Display omitted] • A comprehensive study on renewable energy resources in North America is conducted. • A detailed evaluation of renewable energy potentials is provided. • Important steps for better use of renewable energy resources are summarized. • Emerging technologies for development and management of renewable energy are addressed. • Theoretical and practical challenges in development of renewable energies are highlighted. Energy is an important drive for the economic development and social growth. The energy demand has remarkably escalated due to the technological developments in various governmental, industrial, and municipal activities. The fast growing rate of the energy demand as well as the fuel prices, along with the necessity to control the greenhouse gas emissions are the leading driving forces for effective exploitation of the renewable energy resources. In fact, satisfying the growing global energy demands and mitigating the climate change are of the utmost importance in the modern days. In this review paper, a detailed overview of the development and evolution of the renewable and sustainable energy sources is provided in terms of their types, characteristics, applications, production processes, advantages and disadvantages. Moreover, we discuss the impacts of the renewable energies on health and environment, along with the relevant policies and regulations. Further, the emerging technologies and theoretical and practical challenges in the development of the renewable energies are analyzed. Particularly, this review provides information on renewable and sustainable energies' status and prospects in North America. Central large-scale technology and distributed configurations of the renewable energies might be improved in the North American countries to effectively utilize the renewable energies for producing electricity, biomass-based fuels, and heating in both local/rural and industrial divisions. In addition to employment opportunities stemmed from manufacturing of the renewable energies, its significant impact on the economic development can be enhanced in the US, Canada, and Mexico through development of the renewable energy sources. [ABSTRACT FROM AUTHOR]