REGENERATIVE  GAS FURNACE.

Glasgow Herald, 29 November 1862

Original newspaper text with annotations 2012 by A Moyra

We had the pleasure a few days ago of inspecting, in the premises of Messrs Stevenson and Little, glass manufacturers, Camlachie, a regenerative gas furnace, patented by Messrs C. W and F. Siemans, engineers, Westminster.

By this invention, the workmen employed either at glass making or at iron puddling can proceed with their labour with much greater comfort than if they were engaged at a furnace heated in the ordinary way. The furnace to which we refer is the first that  has been fitted up in Scotland, and if, as we are informed, the consumption of fuel is much less, and the work better executed, these furnaces are likely to be extensively introduced into glass and iron works in this country. The apartment in Messrs Stevenson and Little’s works, in which bottle blowing was being carried on, was entirely free from smoke, and the atmosphere perfectly pure and clear; while the gas which was heating the melting chambers was of the most brilliant description. The regenerative gas furnace is fired entirely with gas, which produces a much more intense and uniform heat than can be obtained by the use of solid fuel. The gas is produced in a separate furnace outside the glass house, and is led by a flue to the melting chamber, where a very great heat is required. A description of the gas producing and glass melting furnaces would be difficult without diagrams, but the principle of working them may be briefly explained. The gas producers, which may be placed at any distance from the furnace where the heat is required, are of a square form, the coals or other fuel being put in by an opening or hopper at the top, and descended on an inclined plane, of about 45 degrees, to the bars or grating at the bottom, where a slow combustion takes place, the coals lying on the bars to the thickness of from 18 to 24 inches.

The gas produced is a combination of olifiant {Note 2012: ethylene}, carbonic oxide {Note 2012: carbon monoxide}, and hydrogen {Note 2012: i.e. this is coal gas}. The  olifiant is evolved from the descending coals by the heat of the burning fuel over the grating. The carbonic oxide is formed by the air passing over the burning fuel producing, in the first instance, carbonic acid gas {Note 2012: CO2}, and, ascending through the mass of carbonaceous matter, and taking up another atom of carbon, it is converted into carbonic oxide. The hydrogen is produced partly from the  ordinary moisture in the coals, but principally from the water introduced into a trough which is placed at the lowest part of the grating. The oxygen of the water is decomposed, and the hydrogen passes off with the other gases.

{Note 2012: That is, the CO2 is reduced to CO, and the H2O reduced to hydrogen!}

The melting chamber has no bars or grate room, like an ordinary furnace, but immediately underneath this chamber are four divisions, to some depth filled with loose fire-bricks, placed about two inches apart, and which the patentees call regenerators. Two of these communicate with each end of the furnace or melting chamber – one being for the passage of air, and the other for gas. The purpose served by these is, that when the gas and the necessary quantity of air for its combustion ascend through the loose brickwork of the regenerators to the furnace, the draught descends through the regenerators at the opposite end, heating intimately the loose brickwork, and after a time the current is reversed, the gas and air coming into the furnace through the recently heated regenerators, bringing back to the furnace the heat that would otherwise have escaped though the chimney, and so on alternately.

The chief recommendations of this furnace are a great economy of fuel and an entire absence of smoke. So much is this the care that the great cone which forms the distinguishing feature of a glass works on the old method is entirely dispensed with in the works of Messrs Stevenson and Little, and only and ordinary ventilator is substituted. The works of Messrs Stevenson and Little are the first that have been built in this country {Note 2012: Scotland} specially for the working out of this new principle. We are glad that it is so successful, as its general adoption will purify our atmosphere of much of the smoke that has been long complained of. There is no reason to doubt this, as the same principle has been found eminently useful in many other than glass furnaces. Among its later applications in England are those of puddling and reheating furnaces, tube welding, steel smelting and for large forging works, Sir William Armstrong being about to erect one at his establishment in Newcastle. The London Gas company and the gas works of Paris are now using this furnace for the heating of their retorts, using the coke of the gas coals for fuel.

On the Continent these furnaces are rapidly superseding the old method, and are also having a more extended application than in this country.

See also related article: William Geddes Borron and Verreville Works: Some Notes