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  • 1.
    Aftab, A.
    et al.
    Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia.
    Ismail, Abdul Razak
    Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia.
    Ibupoto, Zafar
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Akeiber, Hussein J.
    Faculty of Mechanical Engineering, Universiti Teknologi Malaysia.
    Malghani, M.G.K.
    Department of Environmental Management and Policy, BUITEMS Quetta, Pakistan.
    Nanoparticles based drilling muds a solution to drill elevated temperature wells: a review2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 76, p. 1301-1313Article in journal (Refereed)
    Abstract [en]

    Demand of the oil and gas energy is increasing very drastically. Conventional hydrocarbon reservoirs contain below the sealing cap rock (shale) and easily move towards wellbore are at the depletion stage. Therefore, drilling engineers in collaboration with mud engineers, geologists and geophysicists are looking for innovative materials to drill unconventional hydrocarbons reservoir which are distributed at the basin scale and cannot approach easily. Geo-thermal energy wells and most of unconventional reservoirs are occurred at high pressure high temperature (HPHT) conditions. Conventional micro-macro organic drilling mud additives with heat insulator in nature can minimize efficiency while drilling HPHT wells. Oil-based muds (OBM) are strictly restricted due to high toxic level and poor emulsion stability at HT. However, this review suggests that addition of macro size organic particles and inorganic nanoparticles can enhance rheological performance, reduce filtrate loss volume and improve shale inhibition characteristics of environmental friendly water-based mud (WBM). Despite an impressive amount of experimental work has been done over drilling additives and their effect over rheological and shale inhibition, taking into account their literature review are rare. In addition, there is no review work of the knowledge gained to date. This work will hope fully trigger further development and new research topics in the area of drilling muds system.

  • 2.
    Amara, Sofiane
    et al.
    Université de Tlemcen, BP 119 Tlemcen.
    Baghdadli, Tewfik
    Université de Tlemcen, BP 119 Tlemcen.
    Knapp, Samuel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Legionella Disinfection by Solar Concentrator System2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 70, p. 786-792Article in journal (Refereed)
    Abstract [en]

    The current study concerns the fundamental problems of Legionnaires disease. Four decades after Legionnaires' bacteria was first identified there is still a low level of clinical awareness. Humans are infected by inhalation of aerosolized water and/or soil contaminated with the bacteria. Several control methods are available for water disinfection: biocide, ultraviolet light sterilization, copper-silver ionization, ozonation etc. but only thermal treatment can completely eliminate Legionella, which is killed almost instantly at 70 °C. The current paper describes Legionella disinfection by a solar concentrator combined with a heat recovery system that reduces the heat demand. Though this study is made for a small system (160 l of hot water per day) the system can be enlarged (more hot water and more solar collector area) and the results are thus valid also for such larger systems. Here experiments of water treatment by a solar concentrator are summarized and analyzed where the temperature exceeds 80 °C at the outlet of the heat exchanger.

  • 3.
    Ejdemo, Thomas
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Söderholm, Patrik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Wind power, regional development and benefit-sharing: The case of Northern Sweden2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 47, p. 476-485Article in journal (Refereed)
    Abstract [en]

    This paper addresses the question of how investments in wind power can promote regional development and employment, as well as how different benefit-sharing instruments (e.g., community funds etc.) can be used to strengthen the positive impacts. The objectives of the paper are to provide: (a) a survey of previous regional-economic assessments of wind power projects; as well as (b) a quantitative assessment of the employment impacts of an ongoing wind farm investment in the Swedish county of Norrbotten under different benefit-sharing scenarios. Our model-based input–output analysis confirms many of the findings of previous research, such as significant construction work impacts, especially in the presence of local manufacturing. The analysis also illustrates that in the absence of any benefit-sharing mechanism, the employment impacts for Norrbotten during the operating phase will be modest (with an employment multiplier of 1.4). However, even if a relatively low share of the wind power revenues is assumed to accrue to the local government this would have significant positive impacts on employment rates. For this reason, additional research on various types of benefit-sharing instruments is called for, including studies of the associated challenges and trade-offs

  • 4.
    Enrichi, Francesco
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Quandt, Alexander
    School of Physics and Materials for Energy Research Group, University of the Witwatersrand, Johannesburg.
    Righini, Giancarlo C.
    Historical Museum of Physics and Study & Research Centre “Enrico Fermi”.
    Plasmonic enhanced solar cells: Summary of possible strategies and recent results2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 82, no 3, p. 2433-2439Article in journal (Refereed)
    Abstract [en]

    Plasmonic structures for light manipulation at sub-wavelength scale have received great interest in the field of photovoltaic (PV) solar cells for their potential to significantly enhance the cell's efficiency.

    The performance of any solar cell is determined by the capability to absorb incoming light and produce electric charges, which, in turn, has a number of limiting factors. One is related to the ever-reducing size and acceptance angle of the active region. Another is the limited spectral sensitivity of the active material, which cannot make use of significant parts of the solar spectrum.

    Correspondingly, the energy harvesting may be improved in two ways, namely by adopting light trapping schemes and by exploiting spectral modification processes to shift frequencies of the solar spectrum, which are initially not absorbed, into the region of maximum absorption of the cell.

    Plasmonic nanoparticles (NPs) can give a significant boost to both these aspects, by scattering and concentrating the electromagnetic field into the active region of the device, and by doing that within specific spectral regions, which can be properly tuned by optimizing the size, shape, distribution of the plasmonic NPs, and by choosing the right surrounding medium.

    During the last ten years, many papers have been published on very specific issues, but also on general properties of plasmonics applied to solar cells, with a strong increase between 2006 and 2012, followed by a period of significant, but stable, literature productivity. Given these premises, an organized and schematic summary of the main strategies and of the recent results on the field is given in this review, where different plasmonic approaches are compared and discussed, also by recalling specific examples from the literature and providing a few key conclusions to understand the main aspects and the future perspectives of the field.

  • 5.
    Goyal, Rahul
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics. Indian Institute of Technology, Department of Mechanics & Industrial Engineering, Roorkee .
    Gandhi, Bhupendra K.
    Department of Mechanical and Industrial Engineering, Indian Institute of Technology, Roorkee .
    Cervantes, Michel
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    PIV measurements in Francis turbine: A review and application to transient operations2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 81, no 2, p. 2976-2991Article in journal (Refereed)
    Abstract [en]

    Penetration of solar and wind energy into the grid network has raised the concern for grid stability which is generally balanced by operating the hydropower plants over a wide range. This results in several issues, such as rotor-stator interaction (RSI), vortex breakdown, rotating vortex rope (RVR), pressure shocks, vibration, and noise which may lead to failure. Particle Image Velocimetry (PIV) has been used to understand several physical mechanisms in the flow at various operating conditions. A non-negligible uncertainty may arise in the measurements due to calibration, abbreviation, and distortion of the light. Various parameters such as laser sheet thickness, particle type, particle size, particle density, camera resolution, image size and number of images may affect the quality of the measurements. In the present work, a review of PIV measurements performed in hydraulic turbines, mainly Francis, has been carried out. The objective is to develop an experimental set up to perform steady and transient measurements on a model Francis turbine. A maximum deviation of 1.8% in absolute velocity is estimated in the present study as compared to 2–3% reported in the previously performed measurements on Francis turbines. The repeatability of transient measurements is also investigated by extracting two velocity points on a PIV plane

  • 6.
    Patel, Alok
    et al.
    Molecular Microbiology Laboratory, Biotechnology Department, Indian Institute of Technology Roorkee (IIT-R), India.
    Arora, Neha
    Molecular Microbiology Laboratory, Biotechnology Department, Indian Institute of Technology Roorkee (IIT-R), India.
    Mehtani, Juhi
    Molecular Microbiology Laboratory, Biotechnology Department, Indian Institute of Technology Roorkee (IIT-R), India.
    Pruthi, Vikas
    Molecular Microbiology Laboratory, Biotechnology Department, Indian Institute of Technology Roorkee (IIT-R), India.
    Pruthi, Parul A.
    Molecular Microbiology Laboratory, Biotechnology Department, Indian Institute of Technology Roorkee (IIT-R), India.
    Assessment of fuel properties on the basis of fatty acid profiles of oleaginous yeast for potential biodiesel production2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 77, p. 604-616Article in journal (Refereed)
  • 7.
    Pettersson, Fredrik
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Söderholm, Patrik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    The diffusion of renewable electricity in the presence of climate policy and technology learning: the case of Sweden2009In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 13, no 8, p. 2031-2040Article in journal (Refereed)
    Abstract [en]

    The overall objective of this paper is to analyze the impact of climate policy and technology learning on future investments in the Swedish power sector. Methodologically we assess the lifetime engineering costs of different power generation technologies in Sweden, and analyze the impact of carbon pricing on the competitive cost position of these technologies under varying rate-of-return requirements. We also argue that technological learning in the Swedish power sector - not the least in the case of wind power - is strongly related to the presence of international learning and R&D spillovers, and for this reason capacity expansions abroad have important influences of the future cost of power generation in Sweden. The results suggest that renewable power will benefit from existing EU climate policy measures, but overall additional policy instruments (e.g., green certificate schemes) are also needed to stimulate the diffusion of renewable power. Moreover, under a recent European Commission scenario and using estimated learning rates for wind power and the combined cycle gas turbine (CCGT), wind power gains considerable competitive ground due to international technology learning impacts. These latter results are, however, very sensitive to the assumed learning-by-doing rates for wind power and CCGT, respectively.

  • 8.
    Pettersson, Maria
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Ek, Kristina
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Söderholm, Kristina
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Söderholm, Patrik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Wind power planning and permitting: comparative perspectives from the Nordic countries2010In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 14, no 9, p. 3116-3123Article in journal (Refereed)
    Abstract [en]

    The purpose of this paper is to analyze and compare some important institutional and legal preconditions for wind power development in three Nordic countries: Denmark, Norway and Sweden. In the paper a number of historical, institutional and policy-related differences across these countries are highlighted, but most attention is paid to the various territorial planning procedures. The analysis suggests that although public economic support to wind power is necessary to promote its diffusion in the electricity system, similar policy instruments - in terms of both size and design - can induce significantly different developments depending on the legal preconditions for the location and environmental assessment of windmills. The success and failure stories of technology support policies can thus not easily be transferred across country borders. An important conclusion is that in comparison to Sweden the physical planning systems in both Denmark and Norway provide greater scope for implementing a national wind power policy at the local level. For instance, the Danish planning system is vertically integrated, and involves a designation of areas for wind power purposes in the local plans, while the municipalities in Sweden must in some way assent to (i.e., plan for) the establishment of windmills at a certain location in order for the installation to actually take place. Compared to its competitors, wind power is one of the power-generating technologies that tend to have the most to lose from the uncertainties created by planning regulations that leave much discretion to local authorities.

  • 9.
    Reckien, Diana
    et al.
    Faculty of Geo-Information Science and Earth Observation, University of Twente, Enschede, Netherlands.
    Krook-Riekkola, Anna
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Heidrich, Oliver
    School of Engineering, Tyndall Centre for Climate Change Research, Newcastle University, Newcastle upon Tyne, United Kingdom.
    Dedicated versus mainstreaming approaches in local climate plans in Europe2019In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 112, p. 948-959Article in journal (Refereed)
    Abstract [en]

    Cities are gaining prominence committing to respond to the threat of climate change, e.g., by developing local climate plans or strategies. However, little is known regarding the approaches and processes of plan development and implementation, or the success and effectiveness of proposed measures. Mainstreaming is regarded as one approach associated with (implementation) success, but the extent of integration of local climate policies and plans in ongoing sectoral and/or development planning is unclear. This paper analyses 885 cities across the 28 European countries to create a first reference baseline on the degree of climate mainstreaming in local climate plans. This will help to compare the benefits of mainstreaming versus dedicated climate plans, looking at policy effectiveness and ultimately delivery of much needed climate change efforts at the city level. All core cities of the European Urban Audit sample were analyzed, and their local climate plans classified as dedicated or mainstreamed in other local policy initiatives. It was found that the degree of mainstreaming is low for mitigation (9% of reviewed cities; 12% of the identified plans) and somewhat higher for adaptation (10% of cities; 29% of plans). In particular horizontal mainstreaming is a major effort for local authorities; an effort that does not necessarily pay off in terms of success of action implementation. This study concludes that climate change issues in local municipalities are best tackled by either, developing a dedicated local climate plan in parallel to a mainstreamed plan or by subsequently developing first the dedicated and later a mainstreaming plan (joint or subsequent “dual track approach”). Cities that currently provide dedicated local climate plans (66% of cities for mitigation; 26% of cities for adaptation) may follow-up with a mainstreaming approach. This promises effective implementation of tangible climate actions as well as subsequent diffusion of climate issues into other local sector policies. The development of only broad sustainability or resilience strategies is seen as critical.

  • 10.
    Sakar, Selcuk
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Balci, Murat E.
    Electrical and Electronics Engineering, Balikesir University.
    Abdel Aleem, Shady H.E.
    15th of May Higher Institute of Engineering, Mathematical and Physical Sciences, Helwan, Cairo.
    Zobaa, Ahmed F.
    College of Engineering, Design & Physical Sciences, Brunel University London.
    Integration of large- scale PV plants in non-sinusoidal environments: Considerations on hosting capacity and harmonic distortion limits2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 82, no 1, p. 176-186Article in journal (Refereed)
    Abstract [en]

    Distributed generation (DG) penetration in a system may affect power quality, and energy efficiency, if it exceeds a particular value, known as the system's hosting capacity (HC). In this work, a comprehensive overview of hosting capacity and harmonic distortion limits is presented and discussed. The highest allowable penetration level of photovoltaic (PV)-based distributed generation units, hosted on typical industrial distribution systems, was analyzed in terms of the three power quality and energy efficiency performance parameters, namely bus voltage limits, line ampacities, and harmonic distortion limits. The analytical results show that the system's HC decreases with increase in utility side's background voltage distortion and load side's nonlinearity values. The HC level was affected more by the nonlinearity of the load side than by the utility side's background voltage distortion. Therefore, a single-tuned passive filter is suggested for maximizing the system's limited HC. Further, an optimization algorithm was developed to find simultaneously the system's HC and the parameters of the proposed filter, by considering the three performance parameters as constraints. The proposed filter design was found to attain a better level of HC than what can be obtained with a traditional filter design, based on current demand distortion minimization.

  • 11.
    Schmidt, Mischa
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. NEC Laboratories Europe.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Smart Buildings as Cyber-Physical Systems:Data-Driven Predictive Control Strategies for Energy Efficiency2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 90, p. 742-756Article in journal (Refereed)
    Abstract [en]

    Due to its significant contribution to global energy usage and the associated greenhouse gas emissions, existing buildingstock’s energy efficiency must improve. Predictive building control promises to contribute to that by increasing theefficiency of building operations. Predictive control complements other means to increase performance such as refurbishmentsas well as modernizations of systems. This survey reviews recent works and contextualizes these with thecurrent state of the art of interrelated topics in data handling, building automation, distributed control, and semantics.The comprehensive overview leads to seven research questions guiding future research directions.

  • 12.
    Svanberg, Martin
    et al.
    SSPA SWEDEN AB.
    Ellis, Joanne
    SSPA SWEDEN AB.
    Lundgren, Joakim
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Landälv, Ingvar
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Renewable methanol as a fuel for the shipping industry2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 94, p. 1217-1228Article in journal (Refereed)
    Abstract [en]

    Maritime shipping is essential in global trade. The shipping industry uses fossil fuel with significant environmental impact as a result and a transition to renewable fuels may be part of the solution to reduce emissions. A fuel transition needs to be understood at all stages of the supply chain, ranging from feedstock to use in ships’ engines. The purpose of this paper is to do a synthesis of literature to provide an overview of main challenges and opportunities along potential supply chains of renewable methanol for maritime shipping, with a focus on bio-methanol. It is shown that renewable methanol is a technically viable option to reduce emissions from shipping and there are no major challenges with potential supply chains. Minor economic barriers that currently exist have the potential to be overcome with strengthening of environmental targets for shipping or if fuel oil prices revert to higher levels as seen previously.

  • 13.
    Söderholm, Patrik
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Ek, Kristina
    Pettersson, Maria
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Wind power development in Sweden: global policies and local obstacles2007In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 11, no 3, p. 365-400Article in journal (Refereed)
    Abstract [en]

    Recently, the Swedish government adopted a national planning goal of a yearly wind power generation of 10 TWh by 2015, implying a substantial increase from the current 0.6 TWh level. In this paper, we provide an economic assessment of the potential for future wind power investments in Sweden in close conjunction with an analysis of the legal, attitudinal and policy-related uncertainties that face a wind mill investor. It is shown that the economics of Swedish wind power is negatively affected by: (a) the lack of policy stability; (b) public criticism at the local level; and, in particular, (c) the legal provisions governing the assessment of the environmental impacts of wind mills and the planning procedures for mill location. While national and global energy policies as well as the general public point out wind power as particularly environmentally friendly, most of the objections to its expansion at the local level tend to have environmental origins. The interests of those who object to wind mill installations gain strong legal protection, and the municipal territorial planning monopoly in Sweden implies that it is hard to make national energy policy goals heard at the local implementation stage. Compared to its competitors, wind power is the technology that tends to have the most to loose from the risk and uncertainties created by this investment environment. The paper identifies and discusses a number of ways in which the national policy interests could be strengthened at the local level. We discuss the role of citizen participation, as well as solutions within the realms of the legal system. Moreover, since the diffusion of wind power encounters the most strident legal and attitudinal obstacles where it interferes with competing land uses, a move offshore appears to be an efficient strategy from the perspective of a wind mill investor. A stronger political commitment to wind power expansion in legal provisions as well as in the form of long-run stability in policy instrument implementation will probably be necessary to attain the 2015 policy goal.

  • 14. Tan, Zhongxin
    et al.
    Lagerkvist, Anders
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Geosciences and Environmental Engineering.
    Phosphorus recovery from the biomass ash: a review2011In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 15, no 8, p. 3588-3602Article in journal (Refereed)
    Abstract [en]

    Biomass ash, generated during the thermal chemical conversion of biomass for energy production, is an industrial by-product which is often recognized as a solid waste, but there are some useful elements in the biomass ash such as phosphorus, etc. So through some technology and methods, the biomass ash can be transferred into a useful resource. The paper mainly includes the following aspects: biomass ash composition characteristics, biomass thermal chemical conversion for phosphorus and phosphorus recovery technology from biomass ash. Through these aspects literature review, not only the whole biomass ash characteristics was made clear, but also we think that the idea of phosphorus from biomass ash is feasible, especially for some high phosphorus ash such as sludge ash, meat and bone meal (MBM) ash, etc. So the review about phosphorus from the biomass ash is very important practical significance for biomass energy, biomass ash disposal and phosphorus resource.

  • 15.
    Trivedi, Chirag
    et al.
    Waterpower Laboratory, Norwegian University of Science and Technology.
    Cervantes, Michel
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    Fluid-structure interactions in Francis turbines: A perspective review2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 68, no 1, p. 87-101Article in journal (Refereed)
    Abstract [en]

    Competitive electricity prices and reduced profit margins have forced hydraulic turbines to operate under critical conditions. The demand for extended operating ranges and the high efficiency of the turbine runners have forced manufacturers to produce lightweight runners. A turbine runner sometimes experiences resonance when a forced (flow-induced) excitation frequency approaches the runner’s natural frequency, resulting in failure. The cost of structural failure after commissioning is prohibitive. To attain a reliable and safe runner design, understanding of the structural response to flow-induced excitations is important. High amplitude pressure pulsations cause fatigue loading of the blades, which develop cracks over time. The amplitudes are dependent on the flow conditions, type of turbine and stator/rotor vane combinations. The structural response is dependent on the material properties, flow-induced damping and natural frequencies. Moreover, in a hydraulic turbine, changes in flow velocity from less than 1 m s−1 to over 40 m s−1 create challenges in predicting the response.

    The main objective of this article is to review the studies conducted on fluid-structure interactions within hydraulic turbines. Several aspects are reviewed, such as flow-induced excitation, added mass effect, hydrodynamic damping, and blade flutter. Both experimental and numerical studies are discussed in this article. This review also discusses the consequences of an increased number of transient cycles, such as load variation, start-stop and total load rejection, on the turbines and the fatigue loading. Finally, an attempt is made to highlight the important requirements for prospective fluid-structure analysis to fill current gaps in the literature.

  • 16.
    Zhang, Yingying
    et al.
    Department of Material and Chemical Engineering, Zhengzhou University of Light Industry, 450002 Zhengzhou, China.
    Ji, Xiaoyan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Lu, Xiaohua
    State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, 210009 Nanjing, China.
    Choline-based deep eutectic solvents for CO2 separation: Review and thermodynamic analysis2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 97, p. 436-455Article in journal (Refereed)
    Abstract [en]

    CO2 separation plays an important role in energy saving and CO2 emission reduction, both of which are necessary to address the issue of global warming. Ionic liquids (ILs) have been proposed to be “green” solvents for CO2 separation. Unfortunately, the high cost, toxicity, and poor biodegradability of these compounds limit their large-scale application. Deep eutectic solvents (DESs) were recently considered a new type of IL with additional advantages in terms of cost, environmental impact, and synthesis. DESs based on choline salts (i.e., choline-based DESs) are promising candidates for CO2 separation. In this work, the microstructures, physicochemical properties, and water effect of choline-based DESs are surveyed and compared with those of conventional ILs. The properties of choline-based DESs are similar to those of conventional ILs, but research on the latter remains limited. Further study on the microstructures, properties, and separation performance of choline-based DESs considering dynamic factors must be carried out through experimental measurements and model development. Thermodynamic analysis based on Gibbs free energy change is conducted to investigate the performances of choline-based-DESs during CO2 separation from biogas. Choline-based-DESs are screened on the basis of energy use and amount of absorbent needed. The performances of the screened choline-based-DESs are further compared with those of conventional ILs screened in our previous work, as well as commercial CO2 absorbents. Comparisons indicate that the screened DES-based absorbents show great application potential due to their nonvolatility, low energy use, or low amount required. The performances of physical choline-based-DES and 30 wt% MEA for CO2 separation from other gas streams (e.g., flue gas, lime kiln gas, and bio-syngas) are discussed. Considering the high amounts of physical absorbents required to enable separation, further study with techno-economic analysis needs to be carried out.

  • 17.
    Zhao, Xu
    et al.
    China University of Petroleum, Changping, Beijing, China.
    Dahl, Carol
    Mineral and Energy Economics Program, Colorado School of Mines, Golden, CO, United States.
    Luo, Dongkun
    China University of Petroleum, Changping, Beijing, China.
    How OECD countries subsidize oil and natural gas producers and modeling the consequences: A review2019In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 104, p. 111-126Article in journal (Refereed)
    Abstract [en]

    Since fossil fuel subsidies entail significant economic, fiscal, social and environmental costs, more and more attention is being paid to phasing out fossil fuel subsidies. The OECD has recently completed a report quantifying the amount of both producer and consumer subsidies for their member countries, and some work has been implemented on analyzing the effects of consumer subsidy removal. However, there is hardly any investigation of the consequences of producer subsidies. In this paper, we focus on oil and gas producer subsidies of OECD countries and their effects. First, we describe the transfer mechanisms indicated by the OECD report for producer subsidies. In order to recommend models to analyze the influence of removing producer subsidies, we review upstream oil and gas models and provide a taxonomy for them. From them we recommend the most appropriate models for each type of producer subsidy to model upstream decision making. Our contribution in this paper is to categorize the upstream models we have found, compare their main features, as well as recommending best in class models for analyzing the effects of each type of upstream producer subsidy.

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