Papers by Keyword: Furnace

Abstract: The aim of the work was to determine the possibility of not taking into account the orientation (vertical or horizontal) of the studied elements of steel-reinforced concrete slabs with a corrugated profile during their heating in a modular small-sized fire furnace. The work investigated the temperature distributions on the outer surface of the corrugated ceiling profile of a steel-reinforced concrete slab of horizontal orientation simulated in the fire furnace chamber. To create geometric models of the fire furnace chamber and the studied element, a CAD software complex was used. To solve the heat engineering problem, mathematical (numerical) methods were used, based on solving systems of differential equations of continuous media such as the Navier-Stokes equation and the Fourier heat conductivity equation. According to the results obtained, the temperature distribution on the outer surface of the steel profile of the reinforced concrete slab is uniform, the temperature deviation in different places on the surface does not exceed 7 %. The maximum temperature on the heating surface of the steel profile of the reinforced concrete slab in the last minute of computer simulation reached 921 °С and the average temperature at this time over the entire surface of the structure was 917 °С. To determine the appropriate orientation of the test sample during fire tests, a comparison of the obtained temperature distributions on the outer surface of the corrugated profile of a horizontally placed reinforced concrete slab with the temperature distributions on the outer surface of the corrugated profile of a vertically placed reinforced concrete slab, which were given in the previous work was made. Analysis of the average surface temperatures of the corrugated profile of a reinforced concrete slab of horizontal and vertical orientation showed that the temperature distribution over the surface of the profile was uniform in both cases and the results obtained show good reproducibility of the experiment during computer simulation. And the orientation of the tested elements does not affect the temperature distribution over the outer surface of the corrugated profile of a reinforced concrete slab in the simulated furnace.

Abstract: As the energy crisis's impact spreads, energy consumption has emerged as the fundamental impediment to industry's long-term viability. Utilizing and recovering various sources of waste heat can considerably reduce an organization's energy use. Energy conservation is crucial not just for fuel use, but also for the conservation and protection of the global ecosystem. As a result, it is necessary to make a concerted effort to save energy generated by waste heat. This paper aims to develop flue gas as a substitute for wood burning for drying mold at foundry shop of G-7 trading and industrial PLC. Flue gas temperature and velocity were measured at various locations throughout this study, and an analytical computation was done on the flue gas supply system and mold drying chamber. To show what happens within the hot flue gas supply duct and mould drying chamber, Computational Fluid Dynamics (CFD) Ansys software was used. The business benefits by eliminating the usage of wood as a fuel and making the process more cost-effective and environmentally friendly by capturing hot flue gas from the top section of the furnace or chimney and supplying it through duct to the drying chamber to dry the mold. As a result, the negative impact of deforestation will be mitigated, and a favorable working environment will be established.

Abstract: Numerical simulations of a billet heating furnace with direct flame impingement operating in a metallurgical plant were carried out and the results compared to measurements obtained in an industrial environment. The transport equations for mass, momentum, energy and mass of chemical species in reactive flow were computed with the use of ANSYS FLUENT. Turbulence, combustion and radiation were modeled using, respectively, the realizable k-ε model, the finite-rate/eddy-dissipation model and the finite volume scheme. The model was used to simulate the furnace operating under the conditions that occurred during an energy audit carried out at an industrial facility (413 kW firing rate and 80% excess air). The predicted furnace efficiency, 72.5%, is in very good agreement with the one obtained in the energy audit (0.4% difference). The flue gas temperature at the end of the second preheating zone was measured during the energy audit and its value compared to the one predicted. In this case, the agreement between measurements and simulation is not so satisfactory (23% difference). This paper presents the validation of a CFD model of a direct-flame impingement furnace for billet heating in a full-scale industrial situation, which was not previously published, and opens the way for more simulations and detailed studies of the phenomena that occur inside this type of furnace.

Abstract: Questions regarding the oxidizing roasting of raw iron ore materials (agglomerate and pellets) are studied. Features of the phase structure of raw iron ore materials containing titanium and vanadium are discussed. Reducibility, durability, and temperatures of the softening and melting of metallurgical raw iron ore materials are studied in vitro. Object of research – titaniferous ores with various titanium dioxide content. The behavior of agglomerate and pellets in a blast furnace are studied, as well as the influence of their physical and chemical properties on heat and mass transfer processes using a mathematical model of the blast furnace process [1].

Abstract: Experimental studies of concrete in fire or at elevated temperature have traditionally given relatively little scientific attention to quantifying the severity, and to some extent reproducibility, of the thermal boundary conditions imposed on specimens during testing. This paper examines the heat transfer fundamentals of fire testing when controlling the time-history of temperature inside a furnace (or oven), versus controlling the time-history of incident radiant heat flux at a specimen’s exposed surface. The thermal boundary conditions of a concrete specimen during fire testing are fundamentally based on conservation of energy, and thus typically formulated in terms of heat fluxes. While from the standpoint of concrete fire behaviour the aim is typically only to gauge the distribution of temperatures inside concrete; this is rarely explicitly acknowledged or quantified during concrete fire testing. This shows that continued unexamined use of varied heating techniques presents a serious threat to harmonization of the thermal boundary conditions imposed during concrete testing. The current work proposes adopting test control by in-depth temperature distributions or net heat fluxes for a rigorous comparison of the thermal boundary conditions imposed on test specimens when using different heating techniques.

Abstract: The article presents the results stemming from the calculation of the arc efficiency of arc steel melting furnaces during melting of scrap and metallized pellets. Furnaces that use metallized pellets are characterized by less arc efficiency and a higher electric energy consumption than similar pellet furnaces. The calculation results are confirmed by experimental investigations of energy balances of arc steel melting furnaces during melting of scrap and metallized pellets.

Abstract: The questions of metallurgical processing of titanium-containing ores are considered. The ores and concentrates of the Kachkanarsky deposit of low-titanous and high-titanous are studied. The reducibility, durability, temperatures of a softening and melting of metallurgical iron ore raw materials are studied in vitro. Via X-ray the structural analysis are carried out. The calculations by means of mathematical models of pyrometallurgical processes are executed. Possibility of the processing of these ores according to schemes is shown: «blast furnace melting − converter melting» and «metallization – electric melting».

Abstract: Coke production is carried out by coal carbonization. The most frequently used coal is anthracite, which features a very low content of volatile substances that not exceed 7%. Current anthracite production is carried out in rotary furnaces, consists of processes as follows: drying, heating, pyrolysis and calcination. Coke cooling is performed in cooling device located at the end of the furnace. To enhance the performance and reduce the specific heat consumption, use of the preheating device for rotary charge was proposed. The charge granulometry allows using the preheating device based on thin layer principle. Proposed solution was verified by simulations.

Abstract: Gamelan Bali is a set of Balinese traditional musical instruments used to accompany a series of cultural and religious ceremonies or performances. The existence of gamelan has been famous to foreign countries. Therefore, gamelan is not only produced for national orders but also for international orders. Almost 75% of gamelan production process is done using traditional method, namely: smelting, forging, grinding (Sruti) to get the basic tone, and assembly. Smelting process uses traditional furnace, where combustion air is blown from the blower through the injector into the combustion chamber of melting furnace. Open model furnace is used so that the heat generated in the combustion of the fuel is not perfect and it consumes more fuel. This condition, of course, impacts on pollutant factors produced in the combustion process and production cost that is relatively high. To minimize that problem, a change in the combustion air shelters form is done. The use of this method in the smelting process is expected to reduce the production cost, especially in fuel use and to reduce pollutants produced in the combustion process. Studies have shown that the application of the above method reduces the fuel consumption up to 20%. The decrease in the fuel consumption due to the fuel (charcoal) is wrapped by more air, thus it makes the fuel combustion process work better.

Abstract: Metal matrix composites (MMC's) have attracted the attention of researchers for quite some time. In the last 15 years, many studies have been reported in this field of MMC production through various routes. The most commonly used process for producing MMC is stir casting process whereby the reinforcement material is incorporated into the molten metal by stirring. It is a relatively low cost manufacturing process that is capable of producing high quality MMC. However, the process is associated with issues such as attaining uniform distribution of particles, wettability between particles and porosity in the MMCs. Because of these challenges, there has been continuous improvement in the process as well as the design of the furnace. In this research, an innovatively designed bottom tapping furnace has been used to produce the MMCs and the produced sample is characterized.