Production of nanoporous sorbents by partial steam-air conversion of charcoal

An effective sorbent is activated carbon having a developed nanoporous structure with an average pore diameter about 2-4 nm. Perspective method of activated carbon production is the partial steam conversion of the coal bed in boiler furnaces of power plants. The additional thermal energy is produced by burning the syngas. The aim of this work is to study the co-production of activated carbon and syngas by partial steam-air conversion of charcoal. Due to the presence of oxygen in the flow, intensification of conversion occurs. In the laboratory bed reactor, the mass loss curves and the syngas composition were obtained at temperatures of 800°C and 900°C. Two zones with different reaction mechanisms were identified on the height of the bed. The reactions between carbon and steam shift toward hydrogen formation in the oxygen zone. The dependence of the porous structure of the activated carbon on the conversion degree of the raw material is obtained. The maximum of micropores is formed at a conversion degree of 0.5. The material and energy balance of the partial conversion in the laboratory reactor was estimated. © 2018 Institute of Physics Publishing. All rights reserved.Russian Foundation for Basic Research (RFBR

The use technology of backup to enhance fault tolerance for university servers

В настоящей работе рассматриваются различные способы резервирования серверов приложений и баз данных систем, отвечающих за обеспечение учебного процесса в Уральском федеральном университете.In this article we consider different ways of backup application servers and database systems, responsible for the educational process in the Ural Federal University

An Analytical Model for Calculation of the Steel Hardness after Continuous Cooling

A number of modern engineering steel grades were analyzed using the CCT diagrams plotted by means of the dilatometer. The statistical analysis of the experimental data allowed for the determination of the equations connecting the critical cooling rate to achieve fully martensitic microstructure and the martensite hardness with the chemical composition of the steel. The dependence of the steel hardness on the cooling rate in the range of 0.1...30 C/s was determined. It was shown that this dependence had the logarithmic character for every studied steel grade. The equations connecting the coefficients of the logarithmic function with the chemical composition of steel were obtained. © Published under licence by IOP Publishing Ltd.The work was supported by the Act 211 of Government of the Russian Federation, contract № 02.A03.21.0006, the Ministry of Science and Higher Education of the Russian Federation, project №11.1465.2014/K, and by the state assignment of the M.N. Miheev Institute of Metal Physics of Ural Branch of Russian Academy of Sciences, theme “Laser”

Improvement of the Procedure for Sanitary and Quarantine Control of Ships in the Seaports

Objective of the work is to analyze the procedure of ship sanitary and quarantine control in the Rostov Region seaports in order to identify the risks for sanitary and epidemiological welfare of the population and to improve communication process between the authorized ports. Materials and methods. Ship sanitary and quarantine control data on 8314 ships that arrived at Rostov-on-Don, Azov and Taganrog sea border checkpoints were used, considering possible risks for the sanitary and epidemiological welfare of the population. Results and conclusions. The key risks for decision-making whether to perform ship sanitary and quarantine control at the sea border checkpoints are identified. At the stage of the implementation of IHR (2005) it is necessary to consider the ship sanitary and quarantine control at the sea border checkpoints as an unscheduled inspection; availability of preliminary information on the absence of valid sanitary certificates on ships arriving from abroad to be the ground for carrying out ship sanitary and quarantine control at the sea border checkpoints. In order to improve the communication process between authorized ports it is necessary to insert the results of the inspections into ship’s sanitary certificates with issuance of the revealed risks forms

Influence of the coal-derived synthesis gas composition on the thermal stability of ZnO sorbents in the desulfurization process

The priority direction of thermal energy on solid fuels is to increase efficiency and environmental safety, approaching zero emissions of harmful substances. To achieve these goals, they are currently creating new schemes for combined cycle gas turbine units with intra-cycle gasification (IGCC). To improve the efficiency of the IGCC cycle, hot dry desulfurization (HGC) technologies are being developed. HGC uses regenerable sorbents that allow the repeated adsorption of hydrogen sulfide from synthesis gas, among which the most acceptable thermodynamic and operational characteristics are based on ZnO sorbents. The article uses the method of thermogravimetric analysis (TGA) to investigate the development of target reaction capture hydrogen sulfide ZnO-containing sorbent and sorbent reactions with components of synthesis gas in the temperature range up to 1000°C. The sorbent calcined at 900°C shows thermal stability in an inert atmosphere over the entire temperature range studied. Uncalcined sorbents at temperatures of 200 and 600°C emit carbon dioxide in an amount of 1.5-4.5% by weight of the sorbent. At temperatures up to 550°C, the target reaction is basic, and side reactions practically do not develop. The maximum rate of absorption of hydrogen sulfide by the sorbent is observed at a temperature of 600°C. At 500-550°C reactions of a sorbent begin with H2 and CO, at 750-800°C-with carbon, at 850°C-with CH4. The intensity of effect of reagents is defined on degradation of a sorbent by reactionary ability of gases more than temperature. © Published under licence by IOP Publishing Ltd.The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006

INFLUENCE OF CONVERSION PARAMETERS ON ACTIVATED COAL CHARACTERISTICS

The steam conversion products investigation from charcoal large fraction in a layer reactor was carried out. The iodine number dependences on the discharged fraction size, temperature and the process time are obtained. The surface areas and volumes of micro-, meso- and macropores in the obtained coals were measured by BET and BJH methods. It is shown that developed surface with a large number of micropores is formed when the mass decreases in during the conversion more than 35%

The Effect Of Steam On Air Gasification Of Mechanically Activated Coal In A Flow Reactor

A combined steam-gas plant with in-cycle steam gasification of coal and hot gas purification is considered as a promising technology for increasing the efficiency of energy production with simultaneous reduction in environmental impact. To in-tensify steam-air gasification, mechanical activation of fuel is used; it consists in high-stress grinding in a mill-disintegrator. The supply of steam to the gasifier allows an increase in reactivity of fuel, suppression of sorbent decomposition in the unit of hot desulfurization, reduction in the steam load on the shift reactor, increase in useful external work of gas turbine expansion, reduction in nitrogen oxide formation, and general increase in the efficiency and ecological compatibil-ity of energy generation. On the other hand, a significant amount of steam can deteriorate the heat balance and efficiency of the gasifier. In this work, the influ-ence of the steam/fuel ratio on steam-air gasification of mechanically activated Kuznetsk coal in a flow reactor was studied experimentally. The excess air coeffi-cient was maintained constant and equal to 0.51, which corresponded to a temper-ature at the reactor outlet of about 1100 °C. When steam was supplied, the fuel and air-flow rates were adjusted to ensure a constant gas-dynamic regime. To evaluate the obtained regimes, the heat and material balances were compiled. A positive effect of steam on characteristics of the gasification process was revealed. For the studied coal, the maximum degree of coal conversion and the calorific value of synthesis gas are achieved with a steam/fuel ratio of about 0.4 kg/kg. © 2021 Society of Thermal Engineers of Serbia.Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia.This is an open access article distributed under the CC BY-NC-ND 4.0 terms and conditionsResearch results modernization of the experimental stand were obtained within the framework of the state assignment for the IT SB RAS, research results coal gasification was funded by Russian Foundation for Basic Research (project No. 19-38-50071, project No. 18-29-24028)

Investigation of multistage air-steam-blown entrained-flow coal gasification

The aim of the work is using an experimental-computational method to study the process of air-steam-blown entrained-flow gasification of coal with multistage air supply. To achieve this aim, the experiment was conducted on a plant consisting of a swirler into which coal and air are supplied, and a reaction chamber into which steam and multistage air are supplied; the experiment was numerically simulated using a validated CFD model; and the process under study was analysed using the obtained experimental and calculated data. The conducted experimental and computational studies of air-steam-blown gasification allowed determining the effect of steam supply and multistage air supply on the features of the gasification process. Steam injection lowers the temperature of the gas mixture and increases the concentration of hydrogen due to the hydrogasification reaction. The air supply to the reaction chamber increases the temperature of the mixture due to the burning of part of the syngas, while the syngas heating value is reduced by an appropriate amount. The maximum concentration of the syngas combustible components (and hence syngas heating value) is observed before the second point of air supply to the reaction chamber. © Published under licence by IOP Publishing Ltd.Experimental studies, development and using of CFD model were performed within the frames of the grant of the Russian Science Foundation (project No. 19-79-00147) (E.B. Butakov, N.A. Abaimov)

COMPARISON OF THE STRUCTURAL AND DYNAMIC CHARACTERISTICS OF A GAS-DISPERSED FLOW FOR COMBUSTION AND GASIFICATION MODES FOR VARIOUS FUELS IN A WET STAT

The paper analyzes the structural characteristics of gas-dispersed flows in the energy sector. According to the porosity values, using the balance ratios of heat and mass, the mass concentrations of particles of various fuels in the wet state are calculated at a stoichiometric fuel-air ratio.Исследование выполнено при финансовой поддержке Министерства науки и высшего образования Российской Федерации в рамках Программы развития Уральского федерального университета имени первого Президента России Б.Н.Ельцина в соответствии с программой стратегического академического лидерства «Приоритет-2030»