STUDY OF THE INFLUENCE OF COVERINGS OF EXTENDED RADIATING PIPES ON THEM HEAT RADIATION, WHEN HEATING LARGE OBJECTS AND HEATING INDUSTRIAL ROOMS

It is shown that for heating rooms and objects large in length and volume, the use of extended emitting pipes is most appropriate. A method for heating extended objects is described, in which the principle of radiation from radiating pipes with a length of more than 30 m is used in a garage-defroster of railway cars. The heating system of the garage-defroster includes a firebox-heat generator, long pipes of 90 m along the wagons, the control and instrumentation system A. The firebox and the control and instrumentation cabinets are installed in a separate room. The defrost system circuit is essentially a large emitter. The entire heat-radiating circuit is a closed system of direct and return pipes through which a low-temperature (300–400 °C) coolant circulates. The industrial operation of such a system at one of the Ukrainian factories has confirmed the advantages in comparison with the known defrosting systems: reliability, easy operation, high efficiency, safety and environmental friendliness, low capital costs, a minimum of instrumentation and automation, minimal thermal inertia. Ways of increasing the uniformity of temperature and heat radiation from pipes are considered: recirculation of the coolant in the working circuit and applying coatings with different emissivity to the pipe surface. So, with a recirculation rate of the coolant in the working circuit of the industrial defrosting system from 3 to 5, the temperature difference between the surface of the emitting pipes at the first and distant cars was 100 or more degrees. Therefore, cars that are closer to the coolant entrance to the system defrosted faster than others. Two new methods for controlling the radiation intensity of long pipes along their length are proposed: coating coatings with different emissivity on the surface of pipes and coating with maximum and minimum emissivity, which alternate between themselves, around the perimeter of the rings. The results of laboratory experiments on the dependence of the heat radiation of pipes on the methods of applying special coatings to them are shown, which showed that coating in a certain order allows you to change the nature of the distribution of temperatures and heat radiation on surrounding surfaces, significantly reducing their decrease along the length of the radiating pipe. Ref. 18, Fig. 4.

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A study on the Contamination of Microbial in a Geothermal Exchanger Pipe by Lab-experiment

E3S Web of Conferences ◽

10.1051/e3sconf/201911106062 ◽

2019 ◽

Vol 111 ◽

pp. 06062

Author(s):

Hyuntae Kim ◽

Makoto Koganei

Keyword(s):

Global Warming ◽

Energy Consumption ◽

Geothermal Energy ◽

High Efficiency ◽

Ventilation System ◽

Pipe Surface ◽

System A ◽

Reduce Energy Consumption ◽

High Insulation ◽

Reduction Of Energy Consumption

Recently, since global warming has continued, reduction of greenhouse gas CO2 is required. CO2 emissions in the civil area sectors in Japan account for approximately 30%, which is about one-third of the whole of Japan. Therefore, reduction of energy consumption in houses, office and etc. is obviously required. In order to reduce energy consumption of buildings, high-efficiency of machinery, high-insulation, high-airtightness, and use of renewable energy are mentioned. Especially, use of geothermal energy which has almost constant temperature throughout the year has been drawing attention. However, in case of geothermal ventilation system, a fungi, dust, pollen and etc. derived from the outside air are taken directly into the pipe. It is concerned that they cause contamination inside the pipes and breeding of molds, which may lead to odors. The present study analyzed the contamination degree of the pipe surface in the geothermal ventilation system and proposed cleaning frequency in the pipe, cleaning method and so on.

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Planning, implementation, and history of the first 5 years of operation of the Craig, Alaska, pool and school biomass heating system—a case study

10.2737/pnw-gtr-936 ◽

2016 ◽

Author(s):

Allen M. Brackley ◽

K. Petersen

Keyword(s):

Heating System ◽

System A ◽

History Of ◽

Planning Implementation

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District Heating System Flexibility Studies Using Thermal Inertia of Buildings

2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON) ◽

10.1109/rtucon51174.2020.9316600 ◽

2020 ◽

Author(s):

Jevgenijs Kozadajevs ◽

Dmitrijs Boreiko

Keyword(s):

Thermal Inertia ◽

District Heating ◽

Heating System ◽

District Heating System

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Separation of phenols from oils using deep eutectic solvents and ionic liquids

Pure and Applied Chemistry ◽

10.1515/pac-2019-1119 ◽

2020 ◽

Vol 92 (10) ◽

pp. 1717-1731

Author(s):

Yucui Hou ◽

Zhi Feng ◽

Jaime Ruben Sossa Cuellar ◽

Weize Wu

Keyword(s):

Ionic Liquids ◽

Phenolic Compounds ◽

High Efficiency ◽

Deep Eutectic Solvents ◽

Environmentally Benign ◽

Organic Chemical ◽

Environmental Friendliness ◽

Oil Mixtures ◽

Organic Chemical Industry

AbstractPhenolic compounds are important basic materials for the organic chemical industry, such as pesticides, medicines and preservatives. Phenolic compounds can be obtained from biomass, coal and petroleum via pyrolysis and liquefaction, but they are mixtures in oil. The traditional methods to separate phenols from oil using alkaline washing are not environmentally benign. To solve the problems, deep eutectic solvents (DESs) and ionic liquids (ILs) have been developed to separate phenols from oil, which shows high efficiency and environmental friendliness. In this article, we summarized the properties of DESs and ILs and the applications of DESs and ILs in the separation of phenols and oil. There are two ways in which DESs and ILs are used in these applications: (1) DESs formed in situ using different hydrogen bonding acceptors including quaternary ammonium salts, zwitterions, imidazoles and amides; (2) DESs and ILs used as extractants. The effect of water on the separation, mass transfer dynamics in the separation process, removal of neutral oil entrained in DESs, phase diagrams of phenol + oil + extractant during extraction, are also discussed. In the last, we analyze general trends for the separation and evaluate the problematic or challenging aspects in the separation of phenols from oil mixtures.

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Emulators as a Tool for Control Digital System Software Debugging

INFORMACIONNYE TEHNOLOGII ◽

10.17587/it.27.339-349 ◽

2021 ◽

Vol 27 (7) ◽

pp. 339-349

Author(s):

A. D. Ivannikov ◽

Keyword(s):

Graphical Model ◽

High Efficiency ◽

Direct Memory Access ◽

Practical Method ◽

Digital System ◽

Digital Systems ◽

System Software ◽

System A ◽

Software Modules ◽

Operational Program

The simulation of control digital systems at the architecture level, that is, emulation of the instruction set, memory cells and internal programmable registers, as well as the interrupt system and direct memory access is considered. Emulators are used for debugging embedded digital system software and in the development of new custom processors. Requirements for emulators are formalized. It is shown that the main requirements are adequate simulation of digital systems at the architecture level, the presence of a set of convenient debugging modes, as well as high efficiency of emulators, that is, the minimum possible average number of instrumental computer instructions required to simulate one instruction of the target digital system. A classification of the debugging capabilities of emulators and possible ways of implementing debugging modes is given. The composition of the emulators is described. A graphical model of the structure of the emulator is proposed. The simulation process for each instruction is presented as a sequence of execution of smaller operations. If different instructions include the same operations, these operations can be performed by the same software modules. These modules can be included in all the corresponding blocks of the emulator that simulate the execution of instructions, or the emulator can include only one copy of each operational program module, and the module can be accessed while simulating the corresponding instruction. Determination of the structure of the emulator is formalized as an extreme task, the objective function of which is the minimum average time for simulating the execution of one instruction of the target digital system, and the limitation is the maximum allowable memory size of the instrumental computer occupied by the emulator. A practical method for determining the structure of the emulator is proposed.

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Experimental estimation of the efficiency of removing residual amounts of antibiotics and steroid hormones from water with home water purification systems

Vodosnabzhenie i sanitarnaia tehnika ◽

10.35776/vst.2021.03.02 ◽

2021 ◽

pp. 9-15

Author(s):

Ю.А. Ремизова ◽

А.П. Голованова ◽

Д.А. Рудакова ◽

А.Г. Митилинеос

Keyword(s):

Water Purification ◽

High Efficiency ◽

Tap Water ◽

Pharmaceutical Compounds ◽

Model Solution ◽

Capital Costs ◽

Water Purification System ◽

Purification System ◽

Household Water ◽

Purification Methods

Для удаления остаточных количеств фармацевтических соединений, присутствующих в питьевой воде, на всех этапах водоподготовки могут применяться разнообразные способы очистки, основанные на различных физико-химических принципах. В работе приведены результаты экспериментального исследования эффективности удаления с помощью бытовой стационарной системы водоочистки остаточных количеств фармацевтических препаратов – антибиотика левомицетина (хлорамфеникола) и стероидного гормона эстрона – из модельного раствора, приготовленного на основе водопроводной воды с добавлением лекарственных препаратов. Показано, что бытовая система водоочистки обладает способностью существенно снижать остаточные концентрации фармацевтических препаратов левомицетина и эстрона на всем протяжении заявленного производителем ресурса. В секторе бытовой водоочистки установки адсорбционного типа по-прежнему остаются наиболее востребованным типом водоочистных систем, обеспечивающих высокую эффективность удаления различных загрязнителей при минимальных капитальных затратах. To remove residual amounts of pharmaceutical compounds present in drinking water, a variety of purification methods based on various physicochemical principles can be used at all stages of water treatment. The paper presents the results of an experimental study of the efficiency of removing residual concentrations of pharmaceuticals – laevomycetin antibiotic (chloramphenicol) and estrone steroid hormone – from a model solution prepared on the basis of tap water with the addition of drugs, using a home fixed water purification system. It is shown that the home water purification system provides for the significant reduction of residual concentrations of chloramphenicol and estrone throughout the service life declared by the manufacturer. In the household water purification sector, adsorption-type units are still the most in-demand type of water purification systems that provide for the high efficiency in removing various pollutants with minimal capital costs.

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Methanol-Tolerant M–N–C Catalysts for Oxygen Reduction Reactions in Acidic Media and Their Application in Direct Methanol Fuel Cells

Catalysts ◽

10.3390/catal8120650 ◽

2018 ◽

Vol 8 (12) ◽

pp. 650 ◽

Cited By ~ 14

Author(s):

Carmelo Lo Vecchio ◽

David Sebastián ◽

María Lázaro ◽

Antonino Aricò ◽

Vincenzo Baglio

Keyword(s):

Fuel Cells ◽

Oxygen Reduction ◽

Large Scale ◽

High Efficiency ◽

Direct Methanol Fuel Cells ◽

Cell System ◽

Rotating Disk Electrode ◽

Capital Costs ◽

Direct Methanol ◽

Methanol Fuel Cells

Direct methanol fuel cells (DMFCs) are emerging technologies for the electrochemical conversion of the chemical energy of a fuel (methanol) directly into electrical energy, with a low environmental impact and high efficiency. Yet, before this technology can reach a large-scale diffusion, specific issues must be solved, in particular, the high cost of the cell components. In a direct methanol fuel cell system, high capital costs are mainly derived from the use of noble metal catalysts; therefore, the development of low-cost electro-catalysts, satisfying the target requirements of high performance and durability, represents an important challenge. The research is currently addressed to the development of metal–nitrogen–carbon (M–N–C) materials as cheap and sustainable catalysts for the oxygen reduction reaction (ORR) in an acid environment, for application in polymer electrolyte fuel cells fueled by hydrogen or alcohol. In particular, this mini-review summarizes the recent advancements achieved in DMFCs using M–N–C catalysts. The presented analysis is restricted to M–N–C catalysts mounted at the cathode of a DMFC or investigated in rotating disk electrode (RDE) configuration for the ORR in the presence of methanol in order to study alcohol tolerance. The main synthetic routes and characteristics of the catalysts are also presented.

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Improved High-Efficiency Conventional Solar Photovoltaic System: A Novel Approach

Solar Power and Energy Storage Systems ◽

10.1201/9780429458774-2 ◽

2019 ◽

pp. 25-68

Author(s):

Hee-Je Kim

Keyword(s):

High Efficiency ◽

Photovoltaic System ◽

Solar Photovoltaic ◽

System A ◽

Novel Approach ◽

Solar Photovoltaic System

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Heating an electric car with a biofuel operated heater during cold seasons – design, application and test

ACTA IMEKO ◽

10.21014/acta_imeko.v7i4.578 ◽

2019 ◽

Vol 7 (4) ◽

pp. 48 ◽

Cited By ~ 1

Author(s):

Christian Riess ◽

Michael Simon Josef Walter ◽

Stefan Weiherer ◽

Tiffany Haas ◽

Sebastian Haas ◽

...

Keyword(s):

Structural Changes ◽

High Efficiency ◽

Technological Development ◽

Research Work ◽

Heating System ◽

Passenger Compartment ◽

External Energy ◽

Cold Temperatures ◽

Electric Car ◽

Drive Systems

The automotive industry is currently undergoing far-reaching structural changes. Automobile manufacturers are pursuing intensive scientific research and technological development in the field of alternative drive systems, such as electric powertrains. If electric car batteries are charged with regenerative generated electricity, their emission output is zero (from a well-to-wheel view). Furthermore, electric drives have very high efficiency. At cold temperatures, however, the battery power drops due to energy-intensive loads, such as the heating of the passenger compartment, and this consequently reduces the range dramatically. Therefore, the focus of this research work is external energy supply for the required heat capacity. The auxiliary energy may be generated by renewable energy technologies in order to further improve the CO<sub>2</sub> balance of electric vehicles. The paper deals with the design, application, and testing of a biofuel-operated heater to heat the passenger compartment of a battery-powered electric car (a Renault ZOE R240). The practical use of the heating system is analyzed in several test drives, performed during winter 2018. The results as well as the range extension of the electric car that can be achieved by substituting the on-board heating system by the fuel-operated heater are quantified herein.

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