Specific Electrical Consumption Research Articles

Exergetic comparison of electrical heating gasification and water electrolysis assisted gasification for renewable electricity storage

To develop an efficient solution for the storage of renewable electricity and utilization of biomass or waste within the power-to-X concept, the electrical heating gasification (EHG) technology for industrial-scale application was proposed and compared with water electrolysis-assisted gasification (WEG). The two technologies were compared in terms of composition, yield, and exergy efficiency. The results indicate that EHG consumes less electricity and generates syngas with higher chemical exergy. The maximum exergy efficiency of EHG was calculated as 80.76%. Electrical heating gasification is more efficient than WEG based on either the current state or the potential progress in the future. Additionally, the exergy efficiency of water electrolysis ranges between 54.1% and 79.1%, which implies that more efforts are needed in the future to reduce the specific electricity consumption. This work is valuable to guide the development of an electrical heating gasifier and to improve performances of power-to-X technologies.

A novel zero-liquid discharge desalination system based on the humidification-dehumidification process: A preliminary study

As a byproduct of desalination plants, brine is increasingly becoming a threat to the environment, and the design of zero-liquid discharge (ZLD) systems is gaining increasing attention. Existing ZLD systems are limited by a high energy intensity and high plant costs of their crystallizers. This study proposes a novel crystallization method based on the humidification-dehumidification (HDH) process, which exhibits the advantages of a low energy consumption, low component costs and a reduced scaling and fouling potential. A simple experimental setup is first designed to demonstrate the feasibility of the proposed system. Brine concentration and salt crystallization are successfully achieved with air heated to 40 °C as the heat source. Afterwards, a thermo-economic analysis is conducted for the whole system. The specific thermal energy and electricity consumption levels are found to range from 700-900 and 5-11 kJ, respectively, per kg of feed brine. The energy consumption is 56% lower than that of a conventional evaporative crystallizer, and the initial plant cost is reduced by 58%.

The concept of an integrated system of energy efficiency control of artifical oil lift

THEPURPOSE.To consider the problems of controlling the energy efficiency of artificial oil lift. To conduct a comparative analysis of the approaches used to assess the level of energy efficiency and the possibility of energy saving. To submit to a modern possible energy efficiency control system. To identify an effective method for verifying energy efficiency indicators. To propose a concept of an automated control system for energy efficiency of artificial oil lift based on intelligent methods of data analysis.METHODS.Whensolvingtheproblem,themethodoffactoranalysisofspecificpowerconsumption,implementedina model, was used.RESULTS.Thearticledescribestherelevanceofthetopic,considersthefeaturesoftheuseofvariousindicatorsofenergyefficiency.A model of factors for specific power consumption has been developed. In this article, a concept of an automated energy efficiency control system based on intelligent methods has been proposed.CONCLUSION. Usingtheindicatorofspecificelectricityconsumptionforartificialoillift,asanindicatorofenergyefficiency,makesitpossibletoassessthecurrentlevelofenergyefficiencyandidentifythepotentialforfurtherenergysaving.To control the specific consumption of electricity at the mechanized stock of production wells, it is necessary to implement systemic energy metering, additional factor analysis of deviations from the planned values. Using of intelligent methods of data analysis selects the factors of deviation of the specific power consumption and ensures the reliability of energy efficiency control.

Hydrogen as Energy Sources—Basic Concepts

This paper covers the hydrogen technologies regarding the role of hydrogen as an energy carrier and the possibilities of its production and use. It is initially presented the modalities and the efficiency of the current technologies of obtaining hydrogen, detailing its obtaining by the electrolysis of the water, the electrochemical efficiency and the specific consumption of electricity as well as the thermodynamics of the electrochemical processes. The following paragraph addresses hydrogen conversion possibilities. This paragraph details the thermodynamic analysis of the fuel cell, the external characteristic of the fuel cell and the types of fuel cell. The last paragraph addresses the possibilities of using the fuel cells for electrical vehicles and cogeneration systems for buildings.In this context, the traditional transport and distribution grid will have to adapt to the new realities as they will need to actively participate in the internal energy market by the transformation of the traditional electricity grid in energy flow, from unidirectional to bidirectional through the production of hydrogen offering the same facilities as the gas grid.

Application and Analysis of Bipolar Membrane Electrodialysis for LiOH Production at High Electrolyte Concentrations: Current Scope and Challenges.

The objective of this work was to evaluate obtaining LiOH directly from brines with high LiCl concentrations using bipolar membrane electrodialysis by the analysis of Li+ ion transport phenomena. For this purpose, Neosepta BP and Fumasep FBM bipolar membranes were characterized by linear sweep voltammetry, and the Li+ transport number in cation-exchange membranes was determined. In addition, a laboratory-scale reactor was designed, constructed, and tested to develop experimental LiOH production tests. The selected LiCl concentration range, based on productive process concentrations for Salar de Atacama (Chile), was between 14 and 34 wt%. Concentration and current density effects on LiOH production, current efficiency, and specific electricity consumption were evaluated. The highest current efficiency obtained was 0.77 at initial concentrations of LiOH 0.5 wt% and LiCl 14 wt%. On the other hand, a concentrated LiOH solution (between 3.34 wt% and 4.35 wt%, with a solution purity between 96.0% and 95.4%, respectively) was obtained. The results of this work show the feasibility of LiOH production from concentrated brines by means of bipolar membrane electrodialysis, bringing the implementation of this technology closer to LiOH production on a larger scale. Moreover, being an electrochemical process, this could be driven by Solar PV, taking advantage of the high solar radiation conditions in the Atacama Desert in Chile.

CATALYTIC PROPERTIES OF Ni-V COATING IN THE PROCESS OF HYDROGEN RELEASE

Solar and hydrogen energy play an important role in providing a variety of industrial facilities with electricity and heat. One of the priorities of modern industry is to increase the production of environmentally friendly energy source – electrochemical synthesis of hydrogen. Modern methods of electrolysis of water do not meet the need for its use, due to the high cost of electrosynthesis of water-alkaline electrolysis, which depends on the material and energy consumption of electrolysis.
 The useful energy consumption for the production of energy – hydrogen at the cathode and "unnecessary" costs - for the release of oxygen at the anode, depend on the overvoltage of the respective reactions. Therefore, the most important problem of hydrogen energy is the synthesis of electrode materials with low overvoltage of O2 and H2. Electrode materials with low overvoltage will reduce the specific consumption of electricity in obtaining hydrogen by "classical" electrolysis.
 The prospects of reducing the cathodic and anodic overvoltage, which is a significant part of the voltage at the terminals of the cell, for the development of highly efficient and competitive technologies for hydrogen production by low-temperature electrolysis of an alkaline solution have been theoretically substantiated and experimentally confirmed. To reduce the overvoltage of the cathodic hydrogen evolution, it is proposed to modify the surface of the cathodes. The application of a small amount of electrolytic alloys of metals of the iron family with molybdenum and tungsten on nickel, cobalt, titanium and steel electrodes significantly (by 40–50 %) reduces the overvoltage of cathodic release of hydrogen from alkali solution.
 The use of steel electrodes, the surface of which is modified with vanadium and ni-ckel, reduces the voltage drop on the cell during the synthesis of H2 and O2 by 0.2–0.3 V, which creates conditions for reducing energy costs and energy savings.

Experimental study on three-effect tubular solar still under vacuum and immersion cooling

Solar still is widely used for supplying fresh water to small communities in remote areas. One drawback of this technique lies in the low freshwater yield. Recent studies on stills of multi-effect and vacuum design proved their potential for high yield. However, such systems suffer from high electricity consumption and insufficient cooling. In this study, a novel system with a periodic pressure control scheme and water immersion cooling has been proposed to mitigate these defects. A prototype was constructed and associated with a 0.19-m2 solar panel. A 5-day outdoor experiment was conducted to evaluate the overall performance. Results indicated that the highest yield during the test was 9.8 kg/m2 at operating pressure of 40 kPa. A significant performance ratio of 1.87 was achieved with immersion cooling, i.e., 0.42 higher than that with air cooling. Thermal analysis showed that the heat transfer coefficient of water immersion cooling was 15–50 times higher than that of air cooling. Compared with previous vacuum-operated systems, the specific electricity consumption of maintaining vacuum was greatly reduced, i.e., from 21.6 kJ/kg to 1.7 kJ/kg for the case at 60 kPa. The forecast cost of the distilled water is $0.012/kg, representing an affordable desalination technique for off-grid communities.

Результати тестування сучасноЇ індивідуальної доїльної установки

The purpose of the research: comprehensive assessment of the individual milking unit of the company "Kurtsan" (Turkey) during operation. Methods of research: Analysis of the structural features of the individual milking unit performed by the observation method given to test sample, the quality of the machine was evaluated by standardized methods: the quality of the technological process and operational-technological indicators in accordance with the SOU 74.3-37-273, energy indices according to DSTU 2331, economic Indicators according to DSTU 4397, safety indicators and ergonomics according to DSTU IEES 60335-1, DSTU EN 60335-2-70. Research Results: The conducted research confirms a sufficiently high quality of the technological process of selection of milk in cows in the conditions of use of milking installation in a personal economy, which provides favorable conditions for the milking of the cow, taking into account its physiological features. Performance per hour of basic time is 10 heads. Milking installation works on the principle of a closed milking system, thanks to which milk does not contact the environment and immediately from the basin enters a sealed can. Such system protects milk from the possibility of bacterial and physical contamination. Milk obtained during milking by milking installation according to quality indicators (acidity, density, content of somatic cells, mass fraction of dry matter, mass fraction of fat) meets the requirements for the first grade according to DSTU 3662. Milking installation is equipped with a dry vacuum pump. Power consumption during installation does not exceed 0.54 kW. Specific electricity consumption for milking of one cow is 0.05 kWh / head. Annual operating expenses for milking of two cows in the farm are 1591.90 UAH / head. Conclusions. According to the testing of the individual milking plant manufacturing company "KURTSAN", it has been established that this installation reliably performs the technological process of machine milking of cows in milking can for their tethered maintenance and allows you to get milk of the first grade. The total duration of visiting one cow is 5.75 minutes. The average intensity of milk is 1.0 kg / min. Milking machine provides complete bodies of cows. The magnitude of the control manual feed is 50 ml. The milking machine is equipped with an adjustable pulsator of pairwise milking, which creates a manual milking process and works for a working vacuum of 40 ± 1 kPa, which prevents injury to dies and diseases of mastitis. In the cover the "Stop-Milk" system is installed, which prevents milk from entering a vacuum pump during the overflow of the poor, or water while washing All items are compactly assembled on a single cart. However, a small diameter of wheels on an unequal surface creates some inconvenience to the operator during the transportation of the machine with a filled milk capacity. The application of the installation increases the amount of milk received. Its gentle work does not harm the emotional and physical health of the cow: the dysfunctions during operation are not pushed, and light vibration creates a massage effect. Milking installation allows you to significantly reduce the labor of service personnel in an economy with a maintenance of 1 to 10 cows.

Checking the operation parameters of the traction power supply system with a long-term train schedule on the rated section of the railway line

The handling of trains of increased weight and length, consisting of rolling stock with an axle load of 25 tons, and up to 27 – 29 tons in the future, is a difficult technical and economic task facing Russian Railways OAO today. A heavy train cannot be slowed down often, much less stopped, since this leads to a significant loss of energy. In the article, the authors considered the issue of strengthening the traction power supply system on the rated section of the railway line of the Eastern polygon in connection with an increase in the amount of cargo turnover by 2025. Based on the results of the traction calculation, the predicted values of the indicators were obtained. They are the total travel time of the train along the section of the railway line, the free running time of the train, the consumption of active and total electricity, the specific consumption of active and total electricity for each inter-substation zone of the railway line section. The operation parameters of the traction power supply system with a long-term train schedule on the rated section of the railway line are determined. The research results obtained by the authors made it possible to determine the limiting sections and objects of transport infrastructure for the handling of heavy-haul and long freight trains on the rated direction.

Characteristics of the cost of electricity consumption in agricultural production

The paper deals with the issue of the specific contribution of the cost of electricity used for technological needs at agricultural enterprises. The analysis of the technological process of production has been carried out. The classification was completed on the degree of importance according to the volume of electricity consumption. The approximate specific consumption of electricity in the main branches of agricultural production was calculated. The structure of electricity consumption in agricultural sectors is presented. The main directions of optimization of energy consumption costs are shown.

Application of automatic control and electricity measurement system in traction power supply system

In that work the methods of organization an automatic control and metering system for electricity (ACMSE) in the traction power supply system of electrified railway transport are presented. We consider the installation of electricity metering devices on an electric rolling stock, similar in their metrological characteristics (accuracy class, minimum interval of reading, etc.). The definition of the level of consumption, specific consumption and unbalance of electricity for the traction of trains is given. Also, consumption of active and reactive electricity, power losses in the traction network, and the magnitude and duration of the regeneration regimes in AC sections are determined. The estimation of the level of power loss in the traction network under various schemes of connection of traction substations (circuits for connecting two-way and one-way power supply of the contact network) is considered.

Прогнозирование и верификация ключевых показателей энергетической эффективности железнодорожного транспорта

The article reflects the issues of forecasting the target indicators of energy efficiency on the example of JSC «Russian Railways». The approaches selected for assessing the quantitative values of the key performance indicators of the Russian Railways holding in the development of the Energy Strategy for the period up to 2020 and for the future up to 2030 are considered. The accepted methods are conventionally classified into four groups, including: a heuristic method based on the analysis of time trends, an indirect method based on known values of indicators and using mathematical models. The method of forecasting the specific consumption of electricity and diesel fuel for train traction and the energy intensity of the production activity of JSC «Russian Railways» is considered in detail. Regression models have been developed that characterize the dependence of the specific fuel and energy consumption on such indicators as the volume of transportation work, the average mass of the train, and the share of freight work in the total work. In order to assess the accuracy of the obtained forecast values of the indicators included in the energy strategy of JSC «Russian Railways», they were verified by the results of 2017-2019. The results obtained allow us to speak about the sufficient effectiveness of the approaches considered in the article to predict the KPI of JSC «Russian Railways». The error in forecasting the main indicator of energy efficiency of JSC «Russian Railways» - the energy intensity of production activities - was 0,06 %.

Energy benchmarking in educational buildings in the city of Kragujevac - possibilities for energy efficiency improvement

The implementation of energy efficiency measures and use of renewable energy sources in educational buildings can significantly contribute to reducing energy consumption, but also to CO2 emissions in the entire public sector. The paper shows the comparison of energy consumption indicators for 61 elementary school buildings which have previously been divided in 12 groups, according to the period of construction and size, based on the national typology called TABULA, as the first step of further study on how to use the renewable energy sources. The aim of this paper is to use the energy benchmarking process to select representative facilities which are suitable for applying renewable energy sources, for their further energy efficiency improvement. Indicators of annual specific electricity consumption and CO2 emissions per unit area [kWh/m2] and per user [kWh/user] were calculated. After that, from two groups (in which the highest electricity consumption and CO2 emissions are 68.37% and 74.53% of the total consumption/ emissions), one representative facility was selected.

Prospects of Chlorine Method of Aluminum Production in Modern Conditions


 
 
 The results of the feasibility study of the complete aluminum chlorine production cycle in comparison with the conventional method, namely, the extraction of alumina by the Bayer method and subsequent electrolysis of cryolite-alumina melts are reported in this paper. The advantages of the proposed method are: using low-quality Al-containing raw materials and less scarce and aggressive chlorides instead of fluorides; reduction of specific electric power consumption by about 30%; elimination of high-quality carbon-containing materials consumption and harmful emissions into the atmosphere; reduction of capital investments; labor productivity improvement.
 
 
 
 Keywords: aluminum-containing raw material chlorination, electrolysis of aluminum chloride, electricity savings
 
 
 
 
 

Research of the influence of soldering stamps with a deep-additional additive on the indicators of surface metal

Investigations aimed at reducing energy and resource costs during the restoration of stamps by surfacing and at the same time increasing its reliability and durability have recently become especially relevant. A practical solution to the problem is carried out by developing new and improving existing surfacing materials with economically light-burned coatings and charge, using the optimal method of their application. Goal – The aim of this work is to develop a surfacing technology that allows one to reduce the concentration of expensive alloying elements, the mechanical and thermal treatment of the reconditioned tool, and the consumption of the relative mass of the flux and the specific consumption of electricity. Results. When surfacing worn parts, the deposited layers differ in composition and properties from the base materials in most cases. The deposited metal can be alloyed in different ways – due to exchange reactions between the metal and the oxides that are part of the flux, through the gas phase, by introducing alloying elements through electrode or filler materials. Analysis of existing alloys and technologies for their deposition showed that they all have both advantages and disadvantages. On the basis of this, a submerged arc surfacing with a de-energized additive was adopted, which is fed into the head of the weld pool. Originality. The proposed technology made it possible to increase the deposition rate up to 30 g/Ah, the specific energy for weld formation and thermal efficiency by 60...70 % and 40...50 %, respectively, and the assimilation coefficients of alloying elements by 70...80 %; to reduce the part of the base metal in the deposited up to 11...14 % in comparison with surfacing with one electrode. Practical value – The use of the developed surfacing technology made it possible to reduce the concentration of alloying elements and the relative mass of the flux and power consumption, and to increase the main technological parameters of surfacing.

Effect of structure and phase composition on wear resistance of economical alloyed metastable and secondary hardening steels of Cr-Mn-Ti system

Problem. Despite a large number of studies in the field of assessing the causes of hot and cold cracks in the surfacing of wear-resistant surfacing alloys, today the issues of developing relatively inexpensive alloyed wear-resistant surfacing materials and the technology of their application remain relevant. Purpose. The purpose of this work is to study the effect of structure and phase composition on the wear resistance of economically alloyed metastable austenitic and secondary-hardening steels of the Cr-Mn-Ti system, additionally alloyed with Mo, B, V. Methodology. Metastable austenitic, martensitic-austenitic and secondary-hardening steels of the Cr-Mn-Ti system additionally alloyed with Mo, V were investigated. Mechanized surfacing was carried out with alloyed flux-cored wires under fluxes AN-22 and AN-20 with the supply of a de-energized filler flux-cored wire to the head of the welding pool. The use of surfacing with a de-energized flux-cored wire made it possible to reduce the proportion of the base metal in the deposited metal, to reduce the specific consumption of electricity and flux, and to increase the assimilation of alloying elements in the deposited metal. Manual arc surfacing was performed with a CaF2-coated flux-cored wire electrode and a de-energized flux-cored wire in a copper die. Automatic submerged arc surfacing was carried out in the following modes: IN = 300 ... 350 A, UD = 26 ... 30 V, q = 6 ... 10 kJ / cm, with manual surfacing: IN =180 ... 220 A, UD = 25 ... 28 V. Results. The studies carried out confirm the possibility of the formation of a "white band" both in alloys with a high concentration of elements - austenizers (Mn, C, Ni), and when alloying with carbide-forming elements with a relatively low affinity for carbon. (V, Mo). The indicators of resistance to cracking (КС, j-integral, δС), and, consequently, resistance to wear, of secondary hardening martensitic steels are higher than of metastable and tool steels.

The effects of dynamic traffic conditions, route characteristics and environmental conditions on trip-based electricity consumption prediction of electric bus

As prediction of trip-based electricity consumption has become an prerequisite for the deployment of large-scale EB fleets, this study has established random forest-based models to systematically investigate the impacts of environmental conditions, route characteristics, and dynamic traffic conditions. The models have been performed on real-world data collected from 1024 EBs over five consecutive months in Shenzhen, China. The results show that considering all the influencing variables can significantly enhance the prediction performance, but comparatively speaking, the route characteristics contribute the most among the three categories and involving more variables demonstrates greater advantages within the trip length under 20 km. It is also found that the trip length, the number of bus stops and the number of the traffic lights passed rank the top three most influencing factors, while the wet-dry condition is the least one. In addition, the variations under five operation scenarios show similar trend. The trip length and average travel speed are inversely proportional to the specific electricity consumption, while the number of bus stops visited, traffic lights passed, and ambient temperature exhibit a gentle proportional relationship. Moreover, it is suggested to plan the new bus line over 10 km in terms of reducing electricity consumption per kilometre.

КІНЕТИКА СУМІЩЕНИХ КАТОДНИХ ПРОЦЕСІВ У ВОДНОМУ РОЗЧИНІ NaCl

Investigation of the kinetics of combined cathode processes in the electrochemical synthesis of sodium hypochlorite. Intensification of the process of molecular oxygen reduction in aqueous NaCl solution to improve the electrochemical synthesis of sodium hypochlorite using a gas diffusion cathode. Investigation of the effect of the gas diffusion regime on the kinetics of cathode processes, determination of the ranges of potentials and current densities of combined cathode reactions. Cyclic voltammetry for the study of kinetic parameters of the cathode process using the MTech PGP-550M pulse potentiostat. Iodometric titration to determine the concentration of sodium hypochlorite. ranges of potentials of combined cathode processes in conditions without air supply and with air supply through a gas diffusion electrode the possibility of depolarization by air oxygen of the cathode process using the gas diffusion mode of operation of a porous graphite electrode is shown. total and partial reductions (oxygen reduction and hydrogen evolution) polarization dependences without air supply and with air supply in an aqueous solution of 3 mol/dm3 NaCl are constructed to better understand the effect of air supply on the course of combined cathode processes. The obtained polarization dependences prove that the air supply to the gas diffusion electrode leads to an increase in the limiting density of the oxygen reduction current from 2 to 8 mA/cm2, which indicates the prospect of using a gas-diffusion cathode. Changing the nature of the cathode process can significantly reduce the difference in electrode potentials, and by controlling the oxygen supply rate, ClO– can be impeded to the cathode surface. For the field of electrochemical production, it consists in improving the electrochemical synthesis of sodium hypochlorite by increasing the current efficiency and reducing specific electricity consumption. By changing the nature of the cathode process of hydrogen evolution for the reduction of oxygen brought to the cathode-electrolyte interface using a gas diffusion cathode, the problem of cathode reduction of ClО– will be solved without contamination of the final solutions of sodium hypochlorite.

Identification of working reactance of industrial arc furnace equivalent scheme based on known specific electric power consumption for melting of charge

Method of Identification of working reactance of industrial arc furnace equivalent scheme based on known specific electric power consumption for melting of charge taking into account complex (radiation and convection) nature of arc heat exchange in melting space is presented. The solution of the multi-factor problem of determining the share of arc radiation power and convective heating of charge by arcs in the furnace useful power was proposed at MPEI on the basis of analytical methods of the developed electric arc heat exchange model (EAHEM). Method of calculation of specific electric power consumption for melting of solid charge for specified type of arc furnace design is considered.

Удосконалення процесу обробки тіл обертання електричною дугою

In modern mechanical engineering, electrical discharge machining (EDM) methods are widely used for machining bodies of rotation from difficult-to-machine materials. Those methods ensure sparing cutting and make it possible to machine any electrically conductive material irrespective of its physical and chemical properties, in particular hardness. There is a known method for dimensional machining of bodies of rotation with electric arc using a wire electrode tool that is pulled along in the machining area thus "compensating" for that tool's EDM wear and tear. The machining accuracy is therefore significantly heightened. However, when implementing this method, an effect of splashing the working fluid outside the working area of the machine and a pronounced luminous effect from the burning of the electric arc in the machining area are observed. That worsens the working conditions. In addition, when pulling the wire electrode tool along the convex surface of the electrode holder, the sliding friction arises, which eventually leads to mechanical destruction of the contact point. As a result, a deep kerf is formed on the electrode holder. When the depth of the kerf reaches the diameter of the wire electrode tool, the destruction of the electrode holder by the electric arc begins. Consequently, the durability of the electrode holder in the known method is unsatisfactory. A method of dimensional machining of bodies of rotation with electric arc using a wire electrode tool with the immersion of the machining area in the working fluid has been proposed, which makes it possible to improve the working conditions of the operator by eliminating the effect of fluid splashing and removing the luminous effect of arc burning in the machining area. In addition, it has been proposed to make the electrode holder in the form of a roller that rotates with a guide groove for the wire electrode tool, while the nozzle for creating the transverse hydrodynamic fluid flow has been proposed to be mounted in a separate fixed housing that is adjacent to the electrode holder. This technical solution replaces the sliding friction with the rolling one thus enhancing the durability of the electrode holder. Mathematical models of the process characteristics of the DMA-process (dimensional machining with electric arc) for bodies of rotation using a wire electrode tool with the immersion of the machining area in the working fluid have been obtained that make it possible to control the machining productivity, the specific machining productivity, the specific electric power consumption, and the roughness of the surface machined.