The Gas and Hot Blast Smelter and Chemical Condenser.

Te Aroha News, Volume IV, Issue 161, 17 July 1886, Page 3

The Gas and Hot Blast Smelter and Chemical Condenser.

Auckland, July. 12. Messrs Hunt and Carson, patentees of the " Gas and Hot Blast Smelter and Chemical Condenser," were recently asked if they had any objection to explain their patent to the sharebrokers and the general public, as gr6at interest had been manifested <in it, it being so important to the welface of the country to have a cheap smelting process on account of the unlimited quantity of ores available. They readily consented to do so, and stated that they intended to erect a smelting plant at Mr Jas. Kellys foundry, Freeman's Bay, in order to show what could be done, and give some idea of the cost of working. On Saturday afternoon Messrs Hunt and Carson met a large number of gentlemen interested in the mining industry at the Chamber of Commerce, amongst those present being : His Worship the Mayor (Mr W. R. Waddel), Meaars J. M. Clark, G. Aickin, Jas. Bussel), Jas. Philson, J. M. Brigham, H. Green, Harris, W. Lodder, Jqo Reid, Osmond, Hull, Sanders, Alexander, Morpeth, Jaxon, A. Porter, D. B. McDonald, and many others. Mr Car son explained the plan, which showed a furnace for smelting, so constructed that the waste heat passed over two other charges of ore, thus combining smelting and wasting in one furnace. The heat and fumes arising from the furnace first pass into a dust chamber, where the heaviest portion of any metallic substance may be deposited. The heat then travels round cast pipes of a hot air stove to heat up the air for the blast for the furnace. Thus stove may be any one of the numerous patterns of hot-air stoves as used in the iron furnaces in the old country, and which effect a saving of 25 per cent of fuel. From the stove, the fumes are directed through the flue of a Cornish boiler, and being still very hot, steam will be raised in the boiler, thus giving cheap power to tho reduction works, and saving probably £35 to £40 per month for fuel and stokers' wages. At the end of the boiler, a condensing chamber is built, into which the fumes proceed. Here they at once meet sprays of chlorinated water, and any metallic substance is at once precipitated into a concrete tank. Afterwards such substance is treated for recovery of the metals in it. Returning now to the smelting compartment, the ore having been mixed with the necessary fluxes, is heated till it is in a fluid state, and then, but not till then, is the lead added ; the lead hole is then tapped, the lead carrying with it any of the precious metals. The slag is then allowed to flow away, and the next charge which has been roasting is raked into the smelting chamber. It will be thus seen that the lead is not long in the furnace, and not brought into contact with silica till it has combined with the fluxes, thus saving lead from being wasted in the slag, or boing blown up the chimney. Galena may be used instead of lead. The peculiarity about the furnace ip that the fuel is gas, made from slack coal, which is now wasted at all the mines in the colony. Such gas ia made by tiemen'p or Wilson's gas producers, now extensively used in England for melting steel with. The gas does not want purifying like the city supply, for everything in it is converted into a gas for treating. The points uhifh the inventors claim are these :— The utilisation of slack coal to jfive them a cheap fuel as a ; to save lo?s of lead in the fhixep and up the chimney ; to save the losb of silver through volatih-ation, by being caught in the condenser ; and they consider that a saving may be made in fluxes by careful mixing of ore? which will help to flux oue another. One point was elicited in the di«cu?t<ion which ensutd, viz , that the furnace cm be stopped at any time, and a " clean up " take place, «o that paicels of 5 or 10 tons of ore could be put through and its value ascertained. Mr Carson answered a laige number of question?, after which, on the"motion of Mr G. Aickin, a vote of thanks was pas'ed to Messrs Hunt and Carson for the inclination given, after which the meeting terminated. Further developments in connection with the new patent will be awaited with great interest, and if what the patentees claim for it be realised, they will no doubt have achieved a great object in assisting the mining industry both here and oleew here.—" Evening Star."