SMELTING IRON SAND—WHAT WILL IT COST?

New Zealand Mail, Issue 40, 28 October 1871, Page 3

SMELTING IRON SAND—WHAT WILL IT COST?

[to THE EDITOB OF THE NEW ZEALAND MAIL.]

Sib —l see by your issues of the 17th and 19th instant that there is a considerable difference of opinion amongst those interested, as to the cost of a furnace, &0., for smelting the Taranaki iron-sand. Having had considerable experience in the smelting of iron ores, as well as in the erection of works for that purpose, and having reliable data at hand to guide me, I venture to offer a few remarks on the subject, in the hope that they may prove acceptable. The cost of smelting works depends in a great measure upon the quantity of metal which they are intended to turn out per week as well as the quality of that metal, that is to say, whether it is to be steel worth £SO per ton m London, or a fine grey annealed iron which is sometimes called run-steel. As I think it most probable that it will be found advantageous to begin with the latter, I give below the cost in England of a furnace, with adjuncts capable of making about 100 tons per week of fine grey cold blast iron, using ooke as fuel, such a furnace is larger than it would be desirable to use with charcoal, but would not cost more in England than a suitable charcoal furnace with blast, &c., would here :

Castings tor furnace, 57 tons at £6 ... 342 Wrought-iron hoops, 15 tons at £lO ... 150 Bricks for furnacs, 95,000 at £2 ... 190 Labor, erecting furnace ... ... 100 do laying hearth ... ... ... 5 Blast-engine, capable of blowing two furnaces if necessary ... ... ...1,500 Four boilers, 13 tons each, at £l7 ... 884 Engine-house, office, &c. ... ... 400 Seating boilers ... ... 200 £3,771 Should it be found desirable to use a warm blast £l6O would have to be added to the above for heating pipes, and about 3000 more bricks would be required for the stoves, besides which, should there be no ground sufficiently high in the immediate rear of the furnace, a hydraulic or other lift would have to be added for raising the material to be smelted to the furnace top. A cheaper blast engine than the above is in use at some works in the north of England, the price being £920 complete, but 1 do not like them ; and a gentleman, with whom I am acquainted, took two of them out to India to blow a charcoal furnace, and he says they are liable soon to get out of order and are awkward things to repair, I think it will be readily seen from the above figures that the cost of the necessary works would exceed £IBOO. Fuel would, however, be the costliest article at smelting works here, for it will probably not take less than 30 cwt of charcoal to make'a ton of best grey iron, with a cold blast passing into the furnace at the rate of about 2200 cubic feet per minute, and to make a ton of charcoal will take, if made in ovens three to five tons dry wood, and if in open pits, five tons. The number of hands required to work a furnace, such as I have described, is as follows :—Manager, two furnace keepers, two cinder fillers, two fillers at top of furnace, two helpers, four barrow fillers, two haulers for removing cinder, with four engine men. The wages paid them at large works in Monmouthshire is, or rather was, when I was there For keepers, 5s per turn; cinder fillers, 3s 6d ; fillers on top, 4s 8d j helpers, 3s ; barrow fillers, 2s 4d per day ; haulers, 2s 2d per day ; enginemen, first hands, 4s per turn; others, 3s. In addition to their wages a small bonus was paid to keepers, cinder fillers, fillers, and helpers on all iron of a certain quality. The labor at these works averaged 6s 9d per ton on pig iron, covering all expenses of working furnaces, blast, making coke, burning lime, cartage, and office expenses. Of course labor here being so much dearer, the working expenses would be greater in proportion, but some idea may bo formed from the above statement.

Not having seen Mr Smith’s process, or the metal resulting therefrom, it is not possible for me to form an opinion as to the cost of its production, hut an outlay of £12,000 ought to be quite sufficient to start the works, and if Mr Smith has happily succeeded in not only overcoming the mechanical difficulty of smelting the Taranaki iron sand, but also in producing from it, at a cost of £ls per ton, a steel worth £SO per ton in the London market, he has been most fortunate, and any company working by his process must make immense profits. I sincerely hope such news is not too good to be true; at anyrate, if the sand can be smelted at all a very fine iron can be made from it at a cost of half £ls per ton, and which I know from personal experience, as well as from what has been told me by Mr Moseley, of New street, Covent Garden, can be converted into very superior steel without difficulty or great expense. In conclusion, I shall be happy to give the committee appointed on the 17th instant, any information or assistance in my power, and furnish them with dimensions and tracings of charcoal furnaces of any size they may require.—l am, &c., Metallurgist.