scholarly journals Energy consumption of track-based high-speed trains: maglev systems in comparison with wheel-rail systems

2018 ◽  
Vol 4 (3 suppl. 1) ◽  
pp. 134-155 ◽  
Author(s):  
Eckert Fritz ◽  
Larry Blow ◽  
Johannes Kluhspies ◽  
Roland Kircher ◽  
Michael H. Witt
Keyword(s):  
Energy Consumption ◽  
Specific Energy ◽  
Life Cycle Cost ◽  
Energy Demand ◽  
High Speed ◽  
Specific Energy Consumption ◽  
Transportation Systems ◽  
Maximum Speed ◽  
Complete Life Cycle ◽  
Rail Systems

Background: The energy consumption of a high-speed system is an important part of its total operational costs. This paper compares the secondary energy demand of different wheel-rail systems, such as ICE, TGV and Shinkansen, and maglev systems, such as Transrapid and Chuo Shinkansen. In the past, energy values of systems with different conditions (train configuration, dimension, capacity, maximum speed) were frequently compared. The comparative values were often represented by the specific energy consumption based on passenger capacity and line-kilometer values. Aim: The goal is to find a way to compare the specific energy consumption of different high-speed systems without any distortion of results. Methods: A comparison of energy values based on normative usable areas inside the high-speed systems will be described and evaluated in this paper, transforming the results to a more distortion-free comparison of energy consumption of different systems. Results: The results show the energy consumption as an important characteristic parameter of high-speed transportation systems based on an objective comparison and give ranges of expected energy demand of different systems dependent on maximum speed level. Conclusion: Up to the design speed of wheel-rail systems there are slight advantages in terms of energy consumption for the Transrapid maglev. From the perspective of energy consumption under consideration to reduce travel time, high-speed maglev systems represent a promising option for new railway projects. However, a project-specific system decision must be based on a complete life-cycle cost analysis, including investment cost

scholarly journals Batch Reverse Osmosis Desalination Modeling under a Time-Dependent Pressure Profile

Membranes ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 173
Author(s):  
Abdeljalil Chougradi ◽  
François Zaviska ◽  
Ahmed Abed ◽  
Jérôme Harmand ◽  
Jamal-Eddine Jellal ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Reverse Osmosis ◽  
Specific Energy ◽  
Energy Demand ◽  
Specific Energy Consumption ◽  
Pressure Profile ◽  
Recovery Ratio ◽  
Feed Concentration ◽  
Energetic Performance ◽  
Feed Volume

As world demand for clean water increases, reverse osmosis (RO) desalination has emerged as an attractive solution. Continuous RO is the most used desalination technology today. However, a new generation of configurations, working in unsteady-state feed concentration and pressure, have gained more attention recently, including the batch RO process. Our work presents a mathematical modeling for batch RO that offers the possibility of monitoring all variables of the process, including specific energy consumption, as a function of time and the recovery ratio. Validation is achieved by comparison with data from the experimental set-up and an existing model in the literature. Energetic comparison with continuous RO processes confirms that batch RO can be more energy efficient than can continuous RO, especially at a higher recovery ratio. It used, at recovery, 31% less energy for seawater and 19% less energy for brackish water. Modeling also proves that the batch RO process does not have to function under constant flux to deliver good energetic performance. In fact, under a linear pressure profile, batch RO can still deliver better energetic performance than can a continuous configuration. The parameters analysis shows that salinity, pump and energy recovery devices efficiencies are directly linked to the energy demand. While increasing feed volume has a limited effect after a certain volume due to dilution, it also shows, interestingly, a recovery ratio interval in which feed volume does not affect specific energy consumption.

scholarly journals Specific Energy Consumption of a Belt Conveyor System in a Continuous Surface Mine

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5214 ◽  
Author(s):  
Witold Kawalec ◽  
Natalia Suchorab ◽  
Martyna Konieczna-Fuławka ◽  
Robert Król
Keyword(s):  
Energy Consumption ◽  
Specific Energy ◽  
Specific Energy Consumption ◽  
Electric Energy ◽  
Transportation System ◽  
Transportation Systems ◽  
Open Pit ◽  
Design Parameters ◽  
Belt Conveyor ◽  
Electric Energy Consumption

Belt conveyor (BC) transportation systems are considered to be the most effective for handling large volumes of bulk material. With regards to the rules of sustainable development, the improvement of belt conveyor technology is, in many cases, focused on environmental issues, which include the idea of energy usage optimization. The key issue in an energy-efficient transportation system is reducing the value of specific energy consumption (SEC) by increasing conveyor capacity whilst decreasing belt conveyor motion resistance. The main idea of this paper is to conduct an analysis of the modernization of existing belt conveyor transportation systems operated in open-pit lignite mines, in order to achieve relatively small electric energy consumption for a considered transportation task. The first part of the paper investigates the relationship between a conveyor’s SEC and material flow rate for various conveyor design parameters. Then, based on multi-parameter simulations, an analysis of electric energy consumption for a belt conveyor transportation system is carried out. Finally, an energy-saving, environmentally friendly solution is presented.

scholarly journals The efficiency analysis of the SH-25A ball drum mill when grinding industrial products of fossil fuels

2020 ◽  
Vol 180 ◽  
pp. 01003
Author(s):  
Saule Kamarova ◽  
Saule Abildinova ◽  
Angel Terziev ◽  
Aliya Elemanova
Keyword(s):  
Energy Consumption ◽  
Specific Energy ◽  
High Speed ◽  
Fossil Fuels ◽  
Coal Dust ◽  
Specific Energy Consumption ◽  
Operational Characteristics ◽  
Optimal Values ◽  
Speed Mode ◽  
Karaganda Coal

The working characteristics of a laboratory ball drum mill during grinding of Karaganda coal products were studied in order to apply the results obtained to industrial installations. The performed analysis shows that the most complicated and energy-intensive stage of preparation of coal dust is the grinding of fuel. The operational characteristics of the mill productivity, consumed electric power and specific energy consumption in terms of the relative rotational speed of the drum as well as the optimal values of the relative velocity determining the qualitative grinding of the fuel have been determined. The performance of the processed drum mill reaches its maximum at a relative speed of rotation of the drum 0.71 ensuring a waterfall mode of grinding of fuel related to the high-speed mode of a coal-grinding mill. The estimated specific energy consumption for fuel grinding varies in the range from 0.11 kWh/kg up to 0.23 kWh/kg at fuel milling coefficient of Kl = 1.2.

scholarly journals RESEARCH OF WHEAT DRYING IN A MICROWAVE AND COMBINED FILTER-MICROWAVE DRYER

2019 ◽  
Vol 5 ◽  
pp. 70-78
Author(s):  
Oleg Burdo ◽  
Igor Bezbakh ◽  
Serhii Shyshov ◽  
Aleksandr Zykov ◽  
Igor Yarovyi ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Specific Energy ◽  
High Speed ◽  
Specific Energy Consumption ◽  
Microwave Drying ◽  
Convective Drying ◽  
Surface Layers ◽  
Water Release ◽  
Water Elimination ◽  
Kinetics Of

The aim of the conducted study is to determine kinetics of the complex effect of microwave energy supply and filter drying of the process of water release from the wheat layer. There is offered a combination of MW and filter drying. A special feature of this combination must be its more effectiveness and high speed of water elimination from surface layers of wet seeds and, as a result, the productivity increase of the drying way, decrease of specific energy consumption. There was determined the influence of the specific load of the material, radiator power on processes of microwave and filter-microwave drying of wheat seeds. There were compared microwave, filter-microwave and convective drying of seeds by parameters of specific energy consumption, drying speed. The specific energy consumption at microwave drying of seeds was 4 MJ/kg, at filter-microwave drying 3.8 MJ/kg that is lower than existent convective dryers. The speed of microwave drying changes from 0,5 to 3 %/min, filter-microwave – from 0.3 to 0.7 %/min. The speed is at the level of standard convective dryers. The conducted studies allow to recommend a new combined way of FMW drying of seeds with low energy consumption. Revealed features of heating and drying are possible to be used at developing industrial dryers. The base of experimental data is possible to be used for optimizing and determining effective conditions of MW and FMW drying.

Modular operation of membrane bioreactors for higher hydraulic capacity utilisation

2011 ◽  
Vol 63 (6) ◽  
pp. 1241-1246 ◽  
Author(s):  
K. Veltmann ◽  
L. M. Palmowski ◽  
J. Pinnekamp
Keyword(s):  
Energy Consumption ◽  
Specific Energy ◽  
Energy Demand ◽  
Modular Design ◽  
Specific Energy Consumption ◽  
Membrane Bioreactors ◽  
Solid Base ◽  
Capacity Utilisation ◽  
Membrane Aeration ◽  
Influent Flow

Using data from 6 full-scale municipal membrane bioreactors (MBR) in Germany the hydraulic capacity utilisation and specific energy consumption were studied and their connexion shown. The average hydraulic capacity utilisation lies between 14% and 45%. These low values are justified by the necessity to deal with intense rain events and cater for future flow increases. However, this low hydraulic capacity utilisation leads to high specific energy consumption. The optimisation of MBR operation requires a better utilisation of MBR hydraulic capacity, particularly under consideration of the energy-intensive membrane aeration. A first approach to respond to large influent flow fluctuations consists in adjusting the number of operating modules. This is practised by most MBR operators but so far mostly with variable flux and constant membrane aeration. A second approach is the real-time adjustment of membrane aeration in line with flux variations. This adjustment is not permitted under current manufacturers’ warranty conditions. A further opportunity is a discontinuous operation, in which filtration takes place over short periods at high flux and energy for membrane aeration is saved during filtration pauses. The integration of a buffer volume is thereby indispensable. Overall a modular design with small units, which can be activated/ inactivated according to the influent flow and always operate under optimum conditions, enables a better utilisation of MBR hydraulic capacity and forms a solid base to reduce MBR energy demand.

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