Producer Gas.

Timaru Herald, Volume XIC, Issue 13349, 27 July 1907, Page 3 (Supplement)

Producer Gas.

. THEORY OF ITS PRODUCTION. In a paper introduced by Mr Charles H; Wall to the notice of, tha Staffordshire Iron and Steel Institute, the subject of which was " The Use, of Gas for Heating and'; Reheating Purposes,"./the author said: There is no more-; common object than the ordinary domestic ' fire, and vet none ■can illustrate or convey a greater variety of interesting lessons in science, both scientific and. hisioriqal—such as how and when in> ancient .times man first bccam.e~-posses.sed •of it, and the source, from which he obtained it. We can stee in it the production of inns from- the gases,' which are .produced by distillation of the coal'.by the action of heat burning in contact with the air. Here Ave have the glowng coke or carbon, which is also consumed, burning in union/with the air but without flame. .

-When the fire is di"ep and ihic-k, ami contains only glowing carbon, a .short bluish fin mo appears from it", surface. ..This is due to the fact that the carbonic acid gas, which is produced by. complete convbustion of ite carbon, in the lower strata of the fuel, becomes reduced to carbonic ox-ids gas burning again, to carbonic acid.' What passes up the: cliimney in • this case is a mixture of carbonic acid, water vsipour, nitrogen, and the excess of air passing over thj fire. ....... When fresh fuel or coal is. laid on a hot fire an immediate cooling takes place. The cold fuel hike? up a Certain amount of heat, if wet still more, and' soon beginslo giv;i oil' in abundance gases of grey- or yellow tint.. As t!u\ heat increases, streams of flame vhooL up until all. the rising from the eoal\ take lire, and the whole of Ihe upper surface of the fuel is covered with flame. The gases- in. this case are comphtely burned to carbonic acid and. water vapour. The gases first given Off are from burning ■ by, the temperature, at that .spot .being-too low to i.aus.« tlifui to ignite and by tlin further action of the cold air, which mests them in hu-ge quantifies, causing an alteration in their chemical composition of. its- cooling effect. If wo were to enclose the upper part of Hie fireplace and thus stop,the free passage of air to'these gases, a large quantity'of them would remain combustible, and with suitable, .arrangements could be ignited, and consumed with flam?. The same would' happen to the carbonic oxide given off from the fire in its glowing concliton. So that it is possible to chai-ge the form of the fuel into combustible gases which can be, by means of pipss or Hues, carried and conveyed into places'arranged for (he oper-: ation and thero burned.

| These, although elementary, remarks • may hj? useful a ,s illustrating 'in a simple. way some of the primary principles connected wth the action of gas producers, a* compared' with fireplaces for solid fuel. Tn fact,, a gas producer: is an enclosed fireplace in which the fuel'is partially burned, and should be made in-such "a. war so as to produce-the largest amount of combustible gas, and therefore to. obtain the smalleft amount of heat in the place wlie-ve the solict fuel is consumed that will produce the desired effect. The idea of producing fixd from'combustible gases, to.be burned independently, was suggested by obeying the., process going on . during combustion. Firct: the gases escaping from the heaps : in which charcoal was beng made, and then from blast furnaces and waste gaw were found to be combnstibl?. and 'were used in a variety of ways as fuel. Prom that point cams the idea of designing and constructing an apparatus which was 'to ■be used exclusively as a medium for the production of these combustible gases. We find mention of the use of waste gases from 1801 to about 1837.. Gas producers ofji practical kind date from 1839. and in-a,- dumber of forms were used in Germany,' .Sweden, and 1 France for. some years b?foro the introduction of the Siemens produced into Britain in 1,961. Rom2 English inventors, however, foresaw the coming improvement: one of these took out. in 1332. a. patent for the utilisation of the waste heat of blast furnaces, and another one, Moses Pole, who mentions in his nafont. 1841, « gas producer founded on .the pattern of a, blast furnace. Since that time a large number of designs of various forms have been introduced', but latterly the tendency has been a return to thb blast furnace shape with necessary modifications.