US42570A - Improvement in smelting lead ores - Google Patents

Description

ALEXANDER H. EVERETT, or NEW roman. Y.

IMPROVEMENT IN SMELTING LEAD ,ORES.

Specification forming part of Letters Patent No. d2,5'70, dated May 3, 1864.

.To all whom it may concern:

' Be it known that I, ALEXANDER H. EVER- lE'rr,-"'of the city, county, and, State of New York, have invented a new and useful improvement in the reduction and smelting of sulphureted lead ores by which a larger percentage of an improved quality of lead is obtained at less expense for reducing agents, fuel, and labor than by the processes heretofore practiced; and I do hereby declare that the folloyvirg is a clearand exact description of said invention.

The nature of my invention consists in theuse of refuse scraps of tin-plate? in a proper reverberatory for assisting the reductionof lead from the sulphuret of lead to the metallic state. a

In the practice of my invention the reverberatory furnace now commonly constructed for smelting lead may be employed. This is illus trated and described in most standard works on metallurgy, and it is therefore deemed unnecessary to describe it here.

In working my process the reverberatory furnace is first heated to a red heat. Two hun dred and fifty pounds of tin-plate scraps are then spread evenly over the bed. The doors are next closed for a few minutes until the tin= plate scraps have attained a bright-red heat.

The doors are now again opened, and two thousand pounds of the sulphureted leadore pulverized are evenly spread over the heated tin-plate scraps. When this has been done, the doors of the rcverberatory are closed, and so left until the ore has become heated to nearly a dull-red heat, when the doors are again opened and two hundred and fifty pounds more of the tin-plate scraps are carefully and evenly spread over the heated sur face of the ore. -When this has been accomplished, the doors are again closed and the whole mass is brought to a bright-red heat. Doors are still kept closed for about fifteen minutes, and care is exercised to keep the heat of the reverberatory at a constant temperature during this time. When the fifteen minutes have expired,,the doors are again opened and the whole mass is raked and well stirred for two or three minutes, while care is exercised to keep the mass at as uniform a thickness as practicable. This stirring operation should be repeated every fifteen minutes for about two hours. At the expiration of two hours the whole mass will have assumedthe fluid state, when the whole of. the lead will have. been reduced. The tap at the side of the reverberatory the reprovided, leading into a kettle, is drawn, and the lead iaready to be cast into ingots. The furn'aceis next cleared of the slags and the operation just described repeated. 1

I am awarethat iron turnings and shavings from ironlan'ing machines have been employed for melting lead; but. these turnings and shavings have considerable value for reworking and casting into bar, sheet, and cast iron, and are therefore comparatively expensive, while they donot practically answer the purposes for which they are employed by a large percentage as well as the tin-plate scraps, which, on the contrary, cannot be very profitably utilized by any process heretofore known, and are therefore an article almostentirely waste, except for the carrying out of my pro cess.

- The duration'of time required to reduce sulphureted ores by the old process on the scale I have named in the description of my process is never less than between three and four hours, whileby the process I have described the same quantity of ore is reduced in two and a half to three ,hours,*1'naking a saving of one-third of the time employed, and consequently an equal saving of fuel and labor. Practical experience has demonstrated, also, that a superior quality of lead is attained and a larger yield of lead from the ore. In other words, not so much waste is experienced in this process as in the older ones, which have been heretofore practiced.

I have named definite proportions of tinplate scraps and sulphureted ore. I have found these in practice to yield me the best results; but it is obvious that the proportions may be varied according to the nature of the ore to be-treated. I do not desire, therefore, to confine myself to any particular propor tions, as

What I claim as my invention, and desire to secure by Letters Patent of the-United States,

The improved process hereindeseribed for smelting or reducing sulphureted leadores.

In testimony whereof Ihave signed my name to this specification before two subscribing witnesses.

A. H. EVERETT. XVitnesses:

R0123. MOCLENACHAN, WM. H. ARTHUR.