THE BICHEROUX SYSTEM OF FURNACES APPLIED TO THE PUDDLING OF IRON.
Since the year 1872, the large iron works at Ougrée, near Liege, have applied the Bicheroux system of furnaces to heating, and, since the year 1877, to puddling. The results that have been obtained in this last-named application are so satisfactory that it appears to us to be of interest to speak of the matter in some detail.
The apparatus, which is shown in the opposite page, consists of three distinct parts: (1) a gas generator; (2) a mixing chamber into which the gases and air are drawn by the natural draught, and wherein the combustion of the gases begins; and (3) a furnace, or laboratory (not represented in the figure), wherein the combustion is nearly finished, and wherein take place the different reactions of puddling. These three parts are given dimensions that vary according to the composition of the different coals, and they may be made to use any sort of coal, even the fine and schistose kinds which would not be suitable for ordinary puddling. The gases and the air necessary for the combustion of these being brought together at different temperatures, and being drawn into the mixing chamber through the same chimney, it will be seen that the dimensions of the flues that conduct them should vary with the kind of coal used; and the manner in which the gases are brought together is not a matter of indifference.
THE BICHEROUX SYSTEM OF FURNACE.
Vertical Section, and Horizontal Section through MNOPQR
The gas generator consists of a hopper, A, into which drops, through small apertures a, the coal piled up on the platform, D. These apertures are closed with coal or bricks. The bottom of the generator is formed of a small standing grate. The coal, on falling upon a mass in a state of ignition, distills and becomes transformed into coke, which gradually slides down over a grate to produce afterward, through its own combustion, a distillation of the coal following it. But as these are features found in all generators we will not dwell upon them.
The gases that are produced flow through a long horizontal flue, B, into a vertical conduit, E, into which there debouches at the upper part a series of small orifices, F, that conduct the air that has been heated. The gases are inflamed, and traverse the furnace c (not shown in the cut), from whence they go to the chimney. Before the air is allowed to reach the intervening chamber it is made to pass into the sole of the furnace and into the walls of the chamber, so that to the advantage of having the air heated there is joined the additional one of having those portions of the furnace cooled that cannot be heated with impunity.
The incompletely burned gases that escape from the furnace are utilized in heating the boilers of the establishment. The dimensions given these furnaces vary greatly according to the charge to be used. All the results at Ougrée have been obtained with 400 kilogramme charges, and the dimensions of the gas generators have been calculated for Six-Bonniers coal, which does not yield over 20 per cent. of gas.
The advantages of this system, which permits of expediting all the operations of puddling, are as follows:
1. A notable economy in fuel, both as regards quantity and quality.