A study, both experimental and numerical, of temperature distribution during oscillating combustion in a crucible furnace is presented in . The authors found that enhanced heat transfer rate, reduced processing time and increased furnace efficiency with visibly clean emissions are obtained when the conven- tional combustion mode is replaced by the oscillating combustion mode. In  the simulation of thermal analysis of fuel fired crucible furnace to predict the ef- fect of thermal stress and strain on it is studied using commercial simulation software. Here, the layers of the furnace walls having different materials with different thermal coefficient of expansion are considered. A report focused on the application of CFD modeling to solve challenging ventilation problems dur- ing metallurgical industrial process events, such as fume capture in furnaces, is presented in . Some case studies in which various heat and fume sources with complicated geometry and interaction of natural buoyancy are discussed by the authors.
Abstract: The research work presents the design concept and production of a portable Bale-out cast iron crucible furnace that is fired with diesel fuel. Therefore, the work deals with the design, production and testing of oil fired crucible furnace using locally sourced materials. The components of the oil fired crucible furnace are; furnace drum, crucible pot, brick lining, plinth, furnace cover, furnace cover opening and closing mechanism, blower, hose, air valve, burner nozzle, diesel valve, diesel tank and tank stand. Design drawings were produced and mild steel sheet was used for the production of the furnace, while the other components needed for the design were selected based on functionality, durability, cost and local availability. Tests were performed to evaluate the performance of the furnace. The results showed that it took the furnace 15.67mins to completely melt 5kg of aluminum scrap at 651.67 o C with 0.93 litres of diesel and it took 73.33mins to completely melt 5kg of scrap cast iron at 1209.33 o C with 3.93 litres of diesel. The furnace overall cost of production is one hundred and ninety thousand seven hundred naira only (N190,700.00) which is lower than the conventional furnace which cost two hundred and ten thousand naira only(N210,000.00) and is suitable for both in the rural and urban areas. The furnace is environmental friendly without health hazard to the workers and can be moved from one place to another unlike the local one.
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arc furnaces (EAF), induction furnaces, cupolas, reverberatory, and crucible furnaces. Furnace choice is dependent on the alloy system and quantities produced. Most aluminum foundries use either an electric resistance or gas heated crucible furnaces or reverberatory furnaces. The oil fired crucible furnace uses the combustion of diesel as a fire source to heat the crucible and melt the solid metal inside it. Some of the advantages of oil fired crucible furnace are low investment costs, easy operation and maintenance ability, capable of melting small batches of various alloys, the melt can be treated directly in the crucible and the alloy can be quickly and easily replaced as necessary (Mastrukov, 1986). As important as oil fired crucible furnaces to the foundry and manufacturing process, its availability seem to be limited in Nigeria and when available most of them are imported and this is costing the country huge sum of foreign exchange.
One of the most widely used furnaces is the oil- fired crucible furnace. The oil-fired crucible furnace uses the combustion of diesel as a fire source to heat the crucible and melt the solid metal inside it. Some of the advantages of oil-fired crucible furnace are low investment costs, easy operation and maintenance ability, capable of melting small batches of various alloys, the melt can be treated directly in the crucible and the alloy can be quickly and easily replaced as necessary . Oyewale and Olawale (2011) designed and constructed a Mini-Electric Arc Furnace to melt 5kg of steel/cast iron scraps, using locally produced Soderberg electrodes. Tests carried out on the furnace showed that it required 60 minutes to heat up the furnace to the melting temperature of cast iron (115 0 C – 140 0 C). Furthermore, it took about 95 minutes to melt the first charge of 2kg resulting in a melting rate of 21.05g/minute.Alaneme and Olanrewaju (2010) designed and fabricated a diesel fired heat- treatment furnace using locally sourced materials which was aimed at eliminating the use of heating elements requiring electric power which is poorly supplied in the country. The performance of the furnace was observed to have a fast heating rate of 61.24 0 C/min to attain a pre-set temperature of 900 o C and a fuel consumption rate less than 1.41litres/hr.
The production of palm oil from the fruit bunch generates a lot of solid waste product on a large tonnage. These wastes may come from the palm fruit fibre, the palm kernel shell and the empty fruit bunch . The utilization of palm kernel shell for thermal energy production by combustion of the palm kernel as a solid fuel mass is well documented in the literatures . Okoroigwe  highlighted three thermo chemical processes that can be used to convert PKS to renewable energy, these methods includes- gasification, torrefaction and fast pyrolysis. Carbonisation is the term used for the conversion of organic substances to carbon or carbon containing residues through pyrolysis, the process liberates hydrogen, tar and other gaseous substances [12, 13]. Ogbimi  advocates that the design and construction of crucible furnace using carbonized PKS as an intermediate technology, is a step towards localization and institutionalization of technology in Africa.
The master alloy samples taken by both procedures were re-melted one by one with commercially pure aluminum ingots of 99.9% purity. Master alloy ratio to pure aluminum was adjusted according to the equipment's linear range and availability of CRM. The crucible furnace was loaded with accurately weighed aluminum ingots. As the aluminum ingots melted properly, two samples were taken for spark OES analysis. The weight of the samples was also recorded. After that known quantity of aluminum master alloy was added and melting was completed by keeping the metallurgical conditions fulfilled.
Another challenge related to the recruitment of research associates is that of the time commitment they will be entitled to take towards their professional development. Taking six days over a fivemonth period is a significant period of time to reserve for professional development. Many researchers may find it challenging to negotiate access to such programmes with their line manager or may feel that because their contract is running out in a few months, they should focus their attention on data gathering for the project they are employed to deliver. During the first programme, we were concerned that postdoctoral researchers may find it difficult to access a programme requiring a six day commitment. To alleviate the possible challenges negotiating participation, we made the decision to strike a compromise and run one of the Labs over a weekend. In this case, only four days from the programme would be taken from their research project. It was interesting to see that the feedback from the first cohort of participants suggested that we run the programme during the week. This gave us confidence in the planning of Crucible II to ‘dare’ to set the 6 days of the programme during the week and acknowledge that committing to professional development as part of work commitment was a fair request.
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The furnace was loaded by alternating layers (Fig. 3d and 4a). The MS sat across the top of the furnace, receives materials from his team members and fills the furnace. The first layer consists of about 54 kg of charcoal, which he puts on the sand bed. Then he loads the furnace with fresh woods over the first charcoal layer. Another charcoal layer of about 9 kg is added which receives the crushed iron ore of about 35 kg. The ore is disposed and spread along the wall in 12 mounts, so that the areas above the door and the centre of the furnace are not covered as can be seen in the cross-section B-B in Fig. 4d, giving the horse-shoe shape. The space in the middle ensures continuity with the final charcoal layer. This latter at about 45 kg fills the remaining volume of the furnace after the ignition by the deposition within the hollow of iron ore of charcoal embers and barks of Parkia biglobosa tree. This means the ignition takes places simultaneously with the filling. Thus, fire and heat spread from the middle level of the furnace.
As known, in the synthesis of QDs, especially that with core/shell/shell structure, large-scale production is difficult for many methods mainly due to its difficulty to ensure the same temperature and homogeneous mixing in the large volume of solution, which have a great influence on the monodispersity of the nanocrystals. Up to now, large-scale synthesis is still a challenge . Here, in our modified integrated apparatus, the continuous synthesis method makes it possible to realize large-scale synthesis of QDs with core/shell/shell structure. In our experiment, the rate of production can reach as high as 0.1 g/h. As the currently used quartz tube in the furnace only has a diameter of 30 mm, the flow rate is 1.5 L/min. It is easy to improve the production rate using a larger diameter tube or increasing the flow rate. Owing to its continuity, as much core/shell/ shell QDs can be synthesized.
Output power on the coil of this induction heating furnace is not constant. This affair is caused introduced problems in the Section II. For improving feeding system of furnace, we suggest uncontrolled tree phase rectifier convert into controlled three-phase rectifier and design a passive controller for system that by changing the rectifier firing angle, fixed output power of this induction heating furnace on the desired power. Also, suggest single phase switches of inverter convert into IGBT switches and for trigger of these switches, unipolar PWM method is used. For analyzing results of these suggestions electrical feeding system circuit part by part simulated and these simulated details are connected to each other. Consequently, entire circuit is simulated. By usage of this simulated circuit, a passive controller is designed for system. Entire system simulated with desired controller is shown in the Figure.3
After determination of solubility in dil Nitric acid the crucible was kept in 100 ml beaker and 5 ml of Aquaregia was added in the crucible and 10 ml. of water was added to the beaker. Then it was boiled for 10 minutes and sucked by filtration pump. Then dried in oven at 105 o C and weighed. The process was repeated up to constant weight.
In order to develop the ﬂow chart, we have referred to the following items; (a) the production amounts of Al from the statistics of METI 1) and those of the Japan Aluminum Association, 2) (b) the yield ratio in a melting furnace, (d) the dross generation ratio in a melting furnace, (f) the cooled dross generation ratio in a melting furnace, (i) the high-grade residue generation ratio in the recovery process in the Al
The author has clarified the effect of Mn, S, P, elements usually present in cast iron, and of main alloying elements Cr, Ni, Al, Cu on the C and Si activity and equilibrium concentrations in cast iron. The corrections of the equilibrium values of C and Si have been calculated. It has been shown that alloying elements had a substantial impact on the crucible reaction: a significant amount of Cr inhibited the crucible reaction; the reaction was accelerated by significant amounts of Ni, Cu, and especially Al. It has been found that the crucible reaction could be accelerated by passing electrical currents of different intensities and polarities. The author demonstrated the possibility to determine the value of protection potential, able to inhibit the cathode stage without intensification of the anode stage: in the crucible that had no protection voltage, silicon content increased and carbon content decreased faster than in the crucible that had protection voltage.
Water purification for cultivating water spinach or sweet basil by a recirculation aquaponic system was investigated either an oyster shell or ceramic ring. Some results showed that oyster shell significantly increased the pH and calcium in the effluent, which supports the growth of a biofilm, leading to good nitriﬁcation (Hsing Yuan Yen et al., 2016). The inorganic compounds was discussed that it had influence on the thermodynamic characteristics of the composite film, so the flow changes of hydrodynamic behavior were much lower than that of the control film of cellulose acetate (A.M. Pandele et al., 2017). The high water purification performance was mainly attributed to the high photocatalytic activity of dioxide nano fiber system structure and its porous functional layer, which was conducive to rapid infiltration (Hongwei Bai et al., 2015). Recently, the concept of sponge city is introduced into the urban promotion model. Urban drainage and rainwater management are combined with rainwater maintenance and sustainable utilization, which is compatible with urban development and solves water and environmental problems at the same time (Yong Jianga et al., 2018). The influence of catalyst lifetime on the cost of catalytic combustion furnace and the application of pottery water material in water treatment were analyzed in this paper.
390gm of Pinda of Bhunaga Masi mixture kept in closed crucible, crucible and lid dish sealed by mud and clay after drying this was kept in mid part of Koshthi between fuels for strong heating after lique- fying of most part of ball (time taken7.30hour tem.1620ºc) where it stopped to melt crucible left for self-cooling (21hour) after this finished product was taken out, finished product was found deposited mostly at the bottom and very little in surrounding of crucible looked like ash and no any Satva like parti- cle present so procedure was again repeated with above ash and finally found the finish product had crystalline like appearance which contain shiny par- ticle weight of 110gm [yield 29%], grinding of fin- ished product in stone mortar and pestle was done and shiny particle which had metallic appearance, weight was 2gm.
150mins, and the slag formed at the surface of molten metal due to contamination of dust particles is removed, and there by degassing tablet is added in to the crucible to eliminate blow holes and dissolved gasses, and the molten metal is stirred for 5 mins and the molten metal is poured in to the pre heated die and allowed for solidification in the presence of air to get the cast product. B. Method 2 (4% Reinforcement)
Coat each plug with heavy oil or grease, and fit both into their respective places. Use small wooden wedges to get a snug fit. With both plugs securely in place, start tamping in the lining, making sure the castable refractory is well compressed. Do not place too much material between the sleeve and the shell at a time; doing so will produce spaces. When the top of the shell is reached, trowel and smooth the refractory. The furnace is now complete. Now we must have a suitable burner and blower, a blower that will deliver 30 cubic -feet of air per minute. A good blower, particularly one from an industrial vacuum cleaner, will deliver enough air at the right pressure.
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substantially smaller than those in industrial furnaces. The dimensions of the crucibles used would have provided a far larger surface area to volume ratio, affording greater opportunity for reaction between the constituents of the melt and the containing crucible. In all experiments a sintered magnesia based crucible, in which the principal secondary phases were calcium-magnesium silicates, was employed. Evidence for the extent of the interaction between the crucible and the melt is provided by the presence of small variable levels of calcium oxide in the inclusions produced from non-calcium containing deoxidants. The presence of calcium oxide in these inclusions can only be derived from the low melting point calcium-magnesium silicate phases present in the refractory. The proximity of the crucible walls would have enhanced the opportunity for the capture of inclusions from the bulk melt.
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Pfeiffer presented the first biodynamic conference to an English speaking audience at the farm of Lord Northbourne at Betteshanger in Kent, UK, the following year (1-9 July, 1939) (Paull, 2011b). Northbourne (1940) drew on these ideas and published his manifesto of what he called ‘organic agriculture’ in his book Look to the Land published in the year following the ‘Betteshanger Summer School and Conference on Bio- Dynamic Farming’. Pfeiffer migrated to USA and, for a further two decades, he continued his researches and advocacy of Biodynamics, always in pursuit of the proposition that Biodynamics was “for everybody, for all farmers” (Pfeiffer, 1983, p.5). Now nearing its centenary, the Glass House of Dornach has served as home for two enduring anthroposophic endeavours. It was the production centre for the magnificent vibrantly-coloured engraved windows of the Goetheanum, and it was the crucible for evolving Steiner’s Koberwitz lectures through to ‘biodynamic agriculture’, Steiner’s new agriculture for the world.
To carry out first step in compo casting i.e. melting solid cast aluminium ingots to above liquidus temperature and to maintained at semi-solid state to disperse reinforcement. Melting process is carried out in oil fired furnace temperature ranging from 600°C to 750°C. Centrifugal blower equipped with motor is used, to ensure continuous supply of air into furnace. For melting process six graphite crucibles are used. In each crucible, cast aluminium alloy as per volume % mentioned for their respective specimens are weighed and placed inside crucible for further melting process. All six crucible containing different weights of cast aluminium alloy are charged into oil fired furnace and melting of cast aluminium alloy process is progressed uniformly at temperature range of 750±10°C (slightly above liquidus temperature). Reason for heating slightly above liquidus temperature is to eliminate volatile impurities present in cast aluminium alloy.