FACTS FOR FARMERS. STRAW-BURNING PORTABLE ENGINE.

Waikato Times, Volume IV, Issue 210, 13 September 1873, Page 2

FACTS FOR FARMERS. STRAW-BURNING PORTABLE ENGINE.

VN the extensive farms of the prairies of North and South America, steam lias hitherto been httlo employed for agriculturul operation" — not because its advantage over animal power was disputed, but on account of the impossibility of obtuiiung coal or wood as (uel for the enguve, except at a cost übioh would render (heir use utmost prohibitive In South Russia, the United Provinces of Moldavia and Wallachia. and boiiio parts of Hungary, where a daj a'journey may be accomplished without "seeing a tree, steam machinery has been employed for some tune for the purposes of jhrashipg aud grinding, in order to meet the demands of the export cora market ; but the operation has boon curried on at great cost te the farmer, most of the wood for fuel being brou^h^ in carta for a long distance, or if coal un« used it was transported from the nearest port,, where it had usually arrived from England. Although <'oal aud wood are not indigenous to these countries, jet many vegetable products abound, euch as straw, reeds, maize stalks, .fee., which are capable of generating sufficient heat to keep up steam in the- boiler, if a method was discovered to feed uito the (urnace m such a manner %jt each separate piece might be exposed to the action of the fire, and a proper amount of atmospheric air admitted to produce continuous combustion; and as such is always attainable ou the spot, at alrnqst a nominal price, it is self-evident such a discovery would greatly extend the use of steam power in these district!. In some parts of the West Jndies and in Egypt, jugar cane trash, or megass, has been for some time used as fuel, but usually mixed with conl or wood, a.nd in South Russia and op the. banks of the Danube, straw has been burnt in tho portable engines in various ways; but the only one which can bo admitted at all successful was the following :— The bars were taken out of the firebox, and the engine was placed on a brick flue, running diagonally from the ground to the floor of a pit about 10 feet deep, one end of which was hermetically sealed to the bottom of the firebox, and tho other terminated in a sort of oien, in which the straw was burnt. Thp heated gases passed up the flue, through the firebox and tubes of the engine to the chimney. This system was injurious to the lower part ot the firebox, besides" compelling the farmer to bring all his grain m carts to the place where the engine wbi fixed, instead of taking the thrashing machine alongside each stack, which is a great savin* of labour and expense. ° to obviate these difficulties, Mr Schemioth, a Russian engineer, conceived an ideu t at s.traw might be forced" into tho firebox of either a portable or fixed boiler in the form of a fan by means of rollers, so that each separate piece would come under the action of {.he tlanie, allowing more rapid combustion to take pluuo than when the straw was fed into the furnace in »i compressed state, and burnt m a slow smouldering manner $c communicated his idea to Messrs Ransomes, Sims, and Head, of Ipswich, who forthwith commenced to make experiments, and after about fifteen months of continued trial, this firm have at last produced the most perfect engine yet invented for burning straw and other vegetable products. In some of tho early experiments much trouble was experienced in obtaining sufficient atmospheric air through the bottom of the firebox, owing to a deposit of sihcious matter which covered the bars with a sort qf clinker, and nfter trying various schemes, the following simple method was fouiid to bo the most practical : the bars are placed about 4 inches apart, and between each pair is a blunt knife projecting about 2i inches above them. Each knife is attached to a cross bar sliding on two guides under the grate, on end of j this bar terminating m a long bundle extending beyond the j ash pan. When the bars require to be cleaned \he fireman moves the knives backwards an.d forwards, giving them at the 'amo time a side action, which cuts out the clinkers, these falling mto the ash pan, where they are immediately quenched by a je{, of cold water from the feed pump, thus avoiding any danger from tho escape of tho burning ashes m case of windy weather. The apparatus for feeding the engine is self-acting, and dmven by means of a strap, and jteam may bo got up in the same way a$ with any other combustible, by attaching a handle to the feeding rollers and turning them by hand instead of by steam power. One man only is necessary to feed the straw into the engine, provided the material is brought to him and plnced alongside the freding trough. The average consumption is abont fo^r to five pimps the weight of coal, and according to experiments made, about.ten to twelve sheaves of stiaw are required to throsji one hundred sheaves af wheat. On Monrlnj lnst we had an opportunity of witnessing at the makers' works, at Ipswich, a, trial of an engine fitted with the apparatus of which ne lia'w been speaking. The engine I was one of Messrs Jfansomc s, Sjnns, and Head's ordinary 10 horse power portables, exeppt that it was provided wjth a larger firebox than is used i'or coal burning, and that the tubes were of Might lj smaller dimeter than those ordinarily employed On the iirs\ lighting up, the rollers had of course to be turned by hand to feed the straw in.to the firebox, but this is very light labour and can easily be performed j by a boy In thirty-two minutes from applying a light, the steam had got up to 20 1b pressure, and the bteam jet in the chimney was then opened. In eight minutes more, or forty minutes from lighting up, the steam pressure' had reached 31 lb and the engine was then btarted, the steam jet being shut olf, nnd the belt put on to drive the straw feeding rollers. Tho htenin presume then began to rise rapidly, and in eleven tnimilc* mon , or u total Inw of fiay-one minutes fioui lighting up, a pit^uiu ol GUil) udi reached. Subfe-

qumilly, the prcisure was raised to 70 lb, and a break, applied, to the fly-wheel, was loaded &o as to cause tho engine to develop 20 effective horae power, the speed being 140 revolutions per minute. With this loacl steam was maintained steadily and with the utmost ease,' the whole of the an\inge<nent» working admirably The combustion of the straw tias thorough und complete, only a very hw stray articles of un-' burnt material occasionally finding tbijir way into the ash pan, while by an oeeasiqnal use of tue mk? or knives already mentioned, the grate bars were readily kept clear. The water jets in the ash pan, alio thorough] r "fulfilled their purpose of preventing ignited particles f?om flying about— nn important matter where thrashing is, going on— and altogether th<} tnal was a most satisfactory' one in all respects. A very fine ipecimen of one of thpse engines \s exhibited at the Vienna Exhibition at Messrs Ransotnet, Sims, «nd Heads s itand, where it hai attracted great attention. We consider this to be one of the most important stlps that hr.s been made in the construction of portable engine^ since their introduction, as tlieycan now be used m any country where vegetable products be raised, instead, of u& heretofore beinc practicully restricted to those countries where coal or wood can be procured, and a wider extension is thus given to the oppoitumtii's fortheeniplDynvnt of a t«am power than would at first sight be thought possible. * '