Autotherm Equipments Corporation is well known manufacturer,exporter and supplier of Cokeless Cupola Furnaces at market leading price from Coimbatore,, . EcoMelt Cokeless Melting Furnace is a Vertical Shaft Melting furnace and was as a melting unit for Cast iron without use of coke as in a conventional cupola. The development of the cokeless cupola began in the United Kingdom at the foundry of Hayes Shell Cast Limited in the mid s. A pilot furnace was built.
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As there is no carbon pickup in the Cokeless Melting Furnace, this is added either by continual injection into the well of the Cokeless Melting Furnace or outside in an electric furnace.
Some examples will now be described to illustrate what can happen when a cokeless cupola is not run in accordance with the invention. Thus with insufficient fluxing agents the furnace does not produce any metal at all. The bridging was found to have been due to the sticky slag being thrown back up the shaft and coating the charge. This just goes to show that the “obvious” way of increasing slag volume – shovelling on several more shovels of limestone than is needed for our optimum method of operation results in excessive consumption of the spheres and subsequent decrease in the bed height and operational performance of the furnace.
Longer melt campaigns of up to 48 hours are possible with minor modifications in refractory specification and water spray cooling of the shell near the burner area. Washers and increasingly also fabric filters are used for dust removal see Dedusting.
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Process of blowing high-oxygen gases into a molten bath which contains non-ferrous metals. Unit Melting The Cokeless Melting Furnace technology can be applied in the traditional manner as a unit melter when high temperature metal of the right composition is available directly from the cupola into ladles for pouring into moulds.
A conventional coke cupola causes significant pollution. The flux addition will also depend on whether the furnace is to be tapped intermittently in which case a relatively low volume of slag can be handled, or is to be continuously tapped, in which case a higher slag volume is necessary for smooth operation.
A SumoBrain Solutions Company. Similar percentage of sponge iron may also be used in Cokeless Melting Furnace, provided suitable arrangements to charge the same are made. However there is still dirt in the charge and sand sticking to the returns, and so these materials still have to be converted into a fluid slag.
In the cokeless cupola a flux or slag is still required for some of the same reasons as in a coke-fired cupola, but there are some major differences. If insisted by the authority, a simple low cost wet cap may be installed to further reduce the emission level.
A method according to claim 1 which further comprises the step of cokfless slag removed from the furnace by re-introducing at least a portion of the slag as a component of the slag-forming fluxing agents. A method according to claim 2 wherein limestone, dollastone is added to the re-cycled slag as another component of the fluxing agents. A pilot furnace was built during to prove the ideas of melting cast iron with gas at a relatively low temperature and then superheating by some other means.
This example shows, amongst other things, the importance of the slag having sufficient volume to flow during tapping, especially during continuous tapping. Combustion of the coke generates CO 2 and heat eq. Superheating is done by the specially developed spheres that form the refractory bed.
ccokeless With these assumptions he can then calculate what changes must be made to the flux addition in order to obtain a fluid slag at the required tapping temperatures, yet, importantly, with minimum adverse effect on the spheres.
Next Patent Thermal reclamation This is the purpose of the addition of limestone to the charge in the furnace; the limestone acts as a flux to absorb all these unwanted materials and form a slag which can be easily removed from the furnace and handled outside.
A method according to claim 11 which further comprises the step of re-cycling slag removed from the furnace by re-introducing at least a portion of the slag as a component of the slag-forming fluxing agents.
On the other hand, although we propose to add more fluxing material than is conventional, if too much fluxing material is added, with a view to keeping the slag fluid, the spheres will be attacked by the fluxing materials, leading to a high consumption of spheres which not only increases the operating cost but also, because of the reduced thickness of the bed as the spheres are consumed, leads to problems of insufficient superheating of the metal and consequently low tapping temperatures.
Below the grate are the burners which are cokelfss to give partially reducing conditions inside the cupola to reduce oxidation losses. This is certainly true for foundries in India where the cost of meeting new regulations is significant. Anyway in a coke-fired cupola the tapping temperature is higher, which means that if the slag composition is not quite right the extra fuurnace will still enable the slag to be removed quite easily.
This can reach the point where, in a bad condition, the slag can be blown back up the furnace shaft, causing severe operational difficulties and in the worst case the melting of the metal ceases altogether as the metallic charge becomes coated with the viscous slag. Care must be taken not to add too much slag-forming materials. The Gas fired Cokeless Melting Furnace for Iron melting was developed over 30 years ago and a comment passed about its performance in the early days is still very appropriate and probably more relevant, particularly in view of today’s stringent pollution norms.
The flux additions must also melt above the bed and these furnwce are likewise superheated in passing down over the spheres.
A cokeless cupola operating with a clean charge and with what were mistakenly thought to be correct proportions in the charge including 12 Kg of dollastone per charge was found to exhibit very rapid consumption of the spheres, with the consequence that cokelees bed almost vanished by the end of an eight-hour shift, resulting in insufficient superheating and low metal temperature.
A method according to claim 12 wherein limestone, dollastone is added to the re-cycled slag as another component of the fluxing agents. As can be seen in Fig. However, with the injection process used in the Cokeless Melting Furnace, this does not present a problem.