The combustion of coal and the prevention of smoke : chemically and practically considered / by C.W. Williams.

  • Charles Wye Williams
Date:
1854
Catalogue details

Licence: Public Domain Mark

Credit: The combustion of coal and the prevention of smoke : chemically and practically considered / by C.W. Williams. Source: Wellcome Collection.

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    imited and solid. Their respective characters and modes of en- tering into combustion are, however, essentially different; and to our neglect of this primary distinction is referable much of the difficulty and complication which attend the use of coal on the large scale of our furnaces. The first leading distinction is, that the bituminous portion is convertible to the purposes of heat in the gaseous state alone; while the carbonaceous portion, on the contrary, is combustible onlg in the solid state; and, what is essential to be borne in mind, neither can he consumed while they remain united. The use of the term ‘‘fuel^^ as applied to the combustion of coal dming its several processes in the furnace, without re- ference to any particular constituent, whether gaseous or solid, is sufficiently indicative of the inattention to the chemical con- ditions of combustion.* The general impression is, that coal, spoken of under the objectionable term of “fuel,” enters into combustion at once, on the application of heat, and that, during such combustion, it evolves the gaseous matter which it contains. This, however, is neither correct nor scientific, and evades an important feature in the use of coal, namely, the order in which the gaseous and solid portions come into use as heat-giving media. When heat is first applied to bituminous coal, the question naturally arises, What becomes of it? or, What is its effect? A charge of fresh coal thrown on a furnace in an active state, so far from augmenting the general temperature, becomes at * Many instances of inattention might here he given. The following will suffice. In a popular treatise on the steam-engine, by Dr. Lardner, speaking of Brunton’s revolving grate, he observes, “ The coals are let down from the hopper on the grate, and as they descend in very small quantities at a time, they are almost immediately ignited.’’ Here the coal is represented as being ignited, or converted into flame, which is incorrect. Coal-gas may be converted into flame, and coke may be ignited, but coal can neither be ignited nor converted into flame. Again, “ But, until their ignition is complete,” a smoke wiU arise, which, passing to the flue over the burning coal, will he ignited.” Here it is the gas which is ignited — the term smoke being improperly used instead of gas. This, also, is incorrect, as smoke, properly speaking, being once formed, cannot be ignited or inflamed in the same furnace.
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