Charcoal burner

“ To-day charcoal is made commercially by piling wood on steel cars and then pushing the cars into strong walled chambers. The chambers are closed to prevent access of air, and heated to a high temperature. The intense heat transforms the wood into charcoal in a few hours. A student can make in the laboratory sufficient charcoal for art lessons by heating in an earthen vessel wood buried in sand. The process will be slow, however, because the heat furnished by a Bunsen burner is not great, and the wood is transformed slowly. ”

“ Laboratory and Portable Furnaces.—Small air-furnaces with hot plates or sand bath flues were formerly much employed in chemical laboratories, as well as small blast furnaces for crucibles heated with charcoal or coke. The use of such furnaces has very considerably diminished, owing to the general introduction of coal-gas for heating purposes in laboratories, which has been rendered possible by the invention of the Bunsen burner, in which the mixture of air and gas giving the least luminous but most powerfully heating flame is effected automatically by the effluent gas. ”

“ The Charcoal Burners in those stories usually lived in some glade in the middle of the wood, but the Charcoal Burners [296] we are telling about lived on the outside for the reason we have given—but they ought not really to be called 'burners,' because they did not burn anything. Whenever orders came for charcoal they simply took their shovels and went down an aisle into the depth of the inner wood and dug out great hunks of the blackness, which they brought out and stacked upon wagons, and which were conveyed to Vienna and Wiesbaden and Oshkosh and all the other charcoal commercial centers. ”

“ Clark to make a charcoal furnace over a gas-burner, so that, when the charcoal was laid in the furnace, it could be instantly set alight by merely turning on and lighting the gas, letting the flames of gas play through the charcoal. Next I got him to make a large condensing cistern beneath the stove, with an opening from it to convey the carbonic oxide by a tube into the lethal chamber, and with a tap, by which the condensed fluid could be drawn off. ”

“ The burning of three ounces of charcoal, or of a mould candle of six to the pound, produces the same effect. It is not unusual in a factory to burn ten tons of coal a-day, which spoils 3,185,760 cubic feet of air, a mass of a quarter of a mile square and six feet thick. ”

“ The fire is burned in a furnace near the bottom, and the heated smoke is made repeatedly to traverse the structure from side to side along the winding passage before it reaches the top, where a pipe conveys it, when comparatively cold, into a flue in the wall. The heated mass of brick continues to warm the room long after the fuel is burned. The same quantity of fuel which heats a German oven for a day is consumed in an open grate in three hours. In Northern Germany the poorer classes burn turf and charcoal, the better classes use the turf to mix with the stone-coal. ”

“ One mineral, incombustible, seen in the ash residue, which for good coal amounts to barely three per cent. The second, volatile, and which, under the influence of heat becoming gaseous, appears in an open fire as tall flame and smoke, and, where combustion is imperfect, produces soot. The third constituent is carbon or charcoal, familiarly known as coke or cinder, and when burning gives a short, shallow, bluish flame. The carbon and the volatile portions can be raised to a high temperature, and still will not burn unless oxygen be brought into contact with them. ”

“ The shavings, the kindling wood, and the charcoal are in turn ignited, and the burning charcoal develops heat enough to enable the oxygen to combine with the hard coal. Each step in the operation requires more heat than the preceding step. This seems a very simple thing now, but the anthracite beds of Pennsylvania long remained useless because no one had found out how to kindle the fuel, and the discovery was at last made half by accident.
There are some forms of combustion which are very unlike ordinary burning, and yet are essentially the same, being cases of union with oxygen. ”

“ In the melting stoves either arranged as tank or crucible furnaces, the character of the coal must not be neglected, as light dust, iron oxide, or injurious gases will enter into the crucibles through any opening, especially if the draught is not very great. Almost any of the various kinds of fuel may be used, provided that the system of combustion is specially arranged for in the construction of the furnaces. Charcoal is one of the best fuels available, its calorific value being so great ”

“ No room ought ever to be left unoccupied without a guard being placed on the fire. Most of us have had experience of sudden small explosions of the coals, and holes being burnt in the hearthrug, even when there is some one at hand to stamp out the fire at once; and we can imagine what the consequences would be if the hearthrug had been left to smoulder. In the case of steam-pipes, after wood has remained a long time in contact with steam, hot-water, or hot-air pipes, the surface becomes carbonised. During the warm season, the charcoal absorbs moisture. ”

“ The quantity of market refuse passed through six cells of the carbonizer varies from 3 to 10 tons a day, and averages about 41⁄2 tons, from which 15 cwt. of charcoal is obtained. The fuel for burning the charcoal is derived from the ash pit refuse, some selected loads being for that purpose passed over a sloping screen fixed between the upper platform and the furnace floor, the fine ashes which pass through the screen being taken away to the manure heaps, and the combustible parts to the furnaces of the carbonizer. In this way a good deal of the ash pit refuse is got rid of ”

“ The furnace being completely dried, a fire is lighted in the hearth, and fuel gradually added, until the whole is filled to the trundle head, which is the open and lesser base of the truncated cone that forms the body of the furnace. The blast may then be applied, slowly and gently at first, and increasing gradually, until it reach its maximum of intensity. As the blast proceeds, the charcoal gradually burns, and descends; its place is supplied at top by fresh fuel, by ore, and by the earthy matter used as a flux. ”

“ When charcoal burns, it combines with part of the air, and is converted into a gas called carbonic acid, which, although invisible, is much heavier than air, and is a deadly poison; it is therefore necessary, where charcoal is burning, to always have some opening at the bottom of the room. Many fatal accidents have arisen from people sleeping in a small room with a pot of burning charcoal, and no outlet for the poisonous vapour but the chimney, up which it will not pass on account of its weight. ”

“ When burnt in open fireplaces the volatile products given off in the apartment on the first heating have an acrid penetrating odour, which is, however, very generally considered to be agreeable. Owing to the large amount of water present, no very high temperatures can be obtained by the direct combustion of wood, and to produce these for metallurgical purposes it is necessary to convert it previously either into charcoal or into inflammable gas. ”

“ This is the addition of a very small quantity or coal gas, or light petroleum vapors, to the air supplied by a blower or chimney pull, to furnaces burning coke or charcoal. The instant and great rise in temperature of the furnace, and the greater stability of the solid fuel used, are extraordinary. This is, in fact, a practical application of the well-known "flameless combustion," the only signs that the gas is being burnt being a great rise in temperature and a decreased consumption of the solid fuel ”

“ Much charcoal burning is done in the winter, and a pleasant scene it is to find on a snow-clad day lines of smoke rising from the barrenness where once was woodland, men moving round the conical patches from which internal heat has melted the white covering, the rough huts, the incipient flicker which has to be immediately quenched else the whole oven of charcoal be spoiled, the thinning smoke which threatens a dead fire there, to which the woodmen hasten to encourage the hidden blaze. ”

“ To begin the process, they are piled in a furnace between alternate layers of charcoal, the surfaces kept carefully from contact, and are there subjected to fire for eight or nine days. To enable the workmen to watch the process, small trial pieces are so placed that they can be drawn out for examination through a small hole in the front of the furnace. In large furnaces, twelve tons of iron are converted at once. The long-continued heat, which is kept below the melting-point, drives off the impurities; the bars, from contact with the charcoal, become carbonized and hardened ”

“ When laid on a fire they burn away with a feeble lambent flame, indeed some varieties give no flame at all, but burn merely with a red glow, somewhat like charcoal, and at length become consumed without caking. ”

“ Though the constant occurrence of wood embers with the old cinders is conclusive proof that charcoal was the fuel invariably used, yet how it was employed can hardly be determined with exactness, except from what is known of the elementary plans in early use amongst other people, the Egyptians, for instance, the natives of Central Africa, or the iron-workers of Madagascar. A strong draught must necessarily have been made to pass through the ignited fuel, either by placing the furnace so as to take the wind, or by forming it on the principle of the modern wind furnace. ”

“ Charcoal is made by burning wood in such a manner that but little air shall be admitted during the operation, that is to say, only sufficient to keep up the combustion of the more easily destroyed parts of the wood, leaving a black residue called charcoal. ”

“ Eating coals of fire has always been one of the sensational feats of the Fire Kings, as it is quite generally known that charcoal burns with an extremely intense heat. This fervent lunch, however, like many of the feasts of the Fire Kings, is produced by trick methods. Mixed with the charcoal in the brazier are a few coals of soft white pine, which when burnt look exactly like charcoal. These will not burn the mouth as charcoal will. They should be picked up with a fork which will penetrate the pine coals, but not the charcoal, the latter being brittle. ”

“ The wood is disposed in heaps, and covered with earth, so as to prevent the access of any more air than is absolutely necessary for supporting the fire, which is kept up till all the water and oil is driven off, after which the fire is extinguished by shutting up all the air-holes.
We may analyse charcoal either by combustion in air, or rather in oxygen gas, or by means of nitric acid. In either case we convert it into carbonic acid, and sometimes a little potash and some neutral salts remain. ”

“ There is one gas that every one ought to know about, because many persons have been killed by it from want of this knowledge. This gas is made whenever charcoal is burned; and many deaths have occurred from it by burning charcoal in small furnaces in close rooms. This is often done to warm a room where there is no stove or fire-place. As the charcoal burns slowly, the gas is [3046] made, and as it is heavier than air, it spreads, at first, all over the floor. It gets higher and higher, and at length reaches the mouths, of the persons in the room. ”

“ If leather scraps or dried blood are to be worked up, iron tubes are employed, closed at one end, and with a well-fitting lid with a small hole in it at the other. As these bodies give off large volumes of combustible gas during the charring, it is a good plan to lead the vapors from the hole by a bent tube so that they can be burnt and help to supply the heat required and so save fuel. Leather or blood gives a charcoal which hardly requires treatment with hydrochloric acid, for the amount of mineral salts present is so small that its removal appears superfluous. ”

“ If the gases are cooled too much, they will either fall back into the lamp and extinguish the flame, or will be removable only by the draught of a long chimney. It will probably be the aim of the inventor to balance these requirements, and so to produce burners with very short or longer chimneys, according as appearance is to be consulted or the highest possible effect produced. The burner is a ring of brass tubes of considerable diameter, in proportion to the quantity of gas consumed, and thus provides for the delivery of gas expanded by heat. ”

“ The Dyoor and the Bongo appear almost equally ignorant about charcoal-burning. They understand very little about the exclusion of air from the furnaces, or of burning their wood in piles: their science seems limited to the combustion of small fragments heaped up over one another till the fire below them is choked, or subdued by pouring water upon the top. I am not aware whether the other negroes have mastered the secret of charcoal-making ”

“ In this way charcoal may be made to burn brilliantly without air, but not without oxygen. A red-hot bit of charcoal burns in steam, because it decomposes the water; it takes the oxygen, and turns the hydrogen out, which assuming the form of gas, may be collected by means of peculiar chemical apparatus.
Iron and hydrogen are, as mentioned above, about equally combustible: in fact it depends upon the degree of heat, which is the more combustible. If the iron be bright red, it decomposes water, taking away the oxygen; but if it be only dull red, then hydrogen is the more combustible ”