ALTERNATIVE FUELS HE CHINA'S WAR EFFORT
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DURING the four-and-a-half years of war the adoption of alternative fuels,. including producer gas, has taken place in China amid a marked atmosphere of reluctance, Although it would be an exaggeration to slate that the Chinese welcomed with open arms the idea of charcoal-burning gas producers, it is true that the changeover to this type of fuel has been undpr difficulties and on a scale so great as to render.the British effort in this
direction comparatively unnoticeable.. •.
Certainly, a greater necessity than ours was the mother
of the innovation, but there has been a' great great deal of initiativeand ingenuity Shownin the development of producer-gas plants, for the difficulties which originally necessitated the abandoning of pc.",--ol as the standard fuel continue to exist in the form of restricted channels of importation of materials and machine tools necessary for their construction.
Since the cutting of the Burma Road, in 1942, the only alternative route into China has been by air over the mountains from India. Lately this route has become heavily laden, but, naturally, in view of other needs, the amount of material which has been imported to cover the requirements of road transport has been pitifully small compared a. with the relatively-abundant supplies in this country.
Under such conditions of short supply it is not surprising that theft i to be seen along the roads of China, lorries which, for the most part, were originally designed for short-delivery runs in Amefica.
China Has its Official Design of Gas Producer
Early in 1941, the Friends' Ambulance Unit sent a convoy to carry out medical work for the Chinese Army. It fell to the transport section of the convoy to form itself into an organization the job of which was to move supplies to and from the far corners of Free China and Burma Although a detailed history of the F.A.U. (China Convoy) may be of no great interest to the average reader, the following notes, compiled as a result of two years' experience with the unit's transport• section, apply to China's road transport in general.
Charcoal-burning gas producers were one of the first and most widespread types of conversion—and varied were the means for producing! There was no timidity shown in. . the borrowing of ideas from European experience, nor was there Any lack of ingenuity in adapting ideas to existing models.. Just as there is a Government-pattern producer in England,. so, in China, there is a pattern known as the National Resource Cormnission type, and as this is one of the most-widely and successfully used a brief description may prove of interest. •
Like all °tier systems in China, the whole. apparatus is accommodated on the truck itself ; a trailer would be hope
. A2,4 lessly unsuitable for the rough and winding road conditions which preyail, A 3-ft.-squar* hole is cut out of the front near-side of the body to make room for the hopper, which bolds 400500 lb. of charcoal. The tuyere is situated facing forward
from the bottom of hopper, projecting two or three inches inside; it is water-cooled, the tank being arranged on top of the hopper.This tank also supplies water for the drip-feed, which operates at the tuyere tip, the rate of drip, under normal running conditions, being abouttwo drops per second. A hand blower is fitted to the tuyere
for starting purposes. The air-tight ash door is at the rear of the base of the hopper.
The problem of filtering the gases is dealt with in five stages. First, the gas outlet from the hopper (diametrically opposite the tuyere) is-covered by a detachable grid which excludes from the system particles over about f-in. diameter.. The gas then ,passes along a 3-in. pipe made up from sheet metal and welded to a centrifugal filter, around which it passes under its own momentum, throwing out particles of charcoal which drop to the well in the base. Thirdly, a series of cloth filters is employed, which consists of cloth bags stretched over wire frames and inserted into an air-tight cylinder, over a perforated pipe which forms the outlet. The fourth and fifth stages of filtering are contained inone housing, in the bottom of which .is an oil bath through which the gas bubbles before passing through oil-soaked metal turnings, the final filtering agent.
The whole apparatus is spread around the vehicle just beneath the body, so that the gas passes around the hack of the truck and along the length of the off side and under the cab to the engine, thus providing the maximum cooling area.
The air intake (carburetter) consists, merely, of an orifice, a few inches from the manifold, with a butterfly which provides a means for control. Most owners had the gas pipe led straight to the manifold, but the F.A.U. was fortunate enough to have a small stock of Burma petrol,and had its machines fitted with a normal petrol carburetter, and a change-over valve operated from the cab, so that starting Was considerably facilitated. This meant that otherwise unclimbable hills could be negotiated by admit
ting a " whiff " of petrol. But for the less-fortunate drivers there were other methods of persuading their vehicles to ascend!
Lack of Facilities Leads to Operating Difficulties
Chevrolets, Dodge, Ford, and International 3-tonners are the makes which were imported up the Burma Road in greatest numbers, and all of these types can be seen running on charcoal-burning gas producers. Chevrolets and G.M.C.s are probably among the most successful, because of their overhead valves and higher-compression ratios,, but, quite apart from the question of power output, there are difficulties which are common to all conversions made under the conditions which. prevail. Crude welding apparatus, and a lack of machining facilities are the chief reasons for air leaks being common; poor materials cause 'stripped threads and fractures; poor gas filtration renders engine oil somewhat ineffective; and vibration, over-loading and over-revving can cause anything from a burnt-out tuyere to a shattered big-end. All the time, too, there is the probability that these difficulties will be encountered at 1,000 kiloms. or so from one's base and, several hundred from the nearest workshop.
But there are other means for gas propulsion. There is the updraught, tuyere-less type of charcoal burner; there ,are those in which the whole apparatus is carried on the cab roof, and those in which the hopper is a complete 45-gallon petrol drum. Softie have weird and wonderful superchargers fitted, others have two gearboxes set in tandem and, common to all, is a driver's mate, whose chief function is to alight at such times as the gradient threatens to overcome the efforts of the charcoal, run along behind until, as the engine gasps to a stop, he rams a large wooden chock, designed for the purpose, under the rear wheel to prevent any chance of the machine running back. lie
then wearily proceeds to crank the engine, with the assistance of an equally weary -starter-motor. Then there are a few moments' respite while the driver raises the engine revs, to a breath-taking peak before plunging the clutch into engagement with a fury that would spell disaster for some member of the transmission were the engine producing its normal power.
Nevertheless, charcoal has moved the goods. Over mountainous roads, the average condition of which cannot be compa.ted with the worst to be found in England, an unbelievable proportion of China's internal war transport has relied on gas producers.
Drivers Obtain Excellent Performance on Producer Gas As important as the advance of technical and constructive detail on' the part of the Chinese who make these conversions, is the improvedunderstanding of the apparatus
on the part of the driver. It was the practice of the F.A.U. to dispatch its 3-fon charcoal-burning vehicles with a maximum load of 21tons, but, recentlY, a Chevrolet, loaded with, over 3 ions, set out from Lushien (800 ft.), in Szechwan Province, climbed over the 10,000-ft, pass to Kutsing 740 kiloms. aWayr covering the distance in four days, which is no more than the schedule for an oilengined convoy over the same route.
The only lorries designed to run On producer gas to be seen on the roads of China were five H.S.G.-Sentinels, which were exported to China from this country in 1940. Four found their way into the F.A.U. fleet.
Number one met its fate on the first trip up from Rangoon by descending into the River Mekong. The ether three have been on the road spasmodically until, during 1943, number two was dismantled to provide spares. Since then the third has also been used for spares.
This should, in no way, be taken as a sign of the Sentinels' weakness; on the contrary, these vehicles were the toughest and most suitable type for Chinese conditions, and have done really yeoman service carrying medical supplies all over China. But even good vehicles need spares, and these were not available. This is a sad state of affairs which British exporters to all Far Eastern countries would do well 40 note, for one can hardly blame prospective purchasers for preferring to own a vehicle for which spares can be obtained without having to wait an indefinite period for their export from the United Kingdom. It is a complaint that is heard over and over again in India and Burma as well as in China that, although British machines may be the best, it is difficult to find a good spares service.
Indifferent Results Obtained With
Alternative Liquid Fuels
Meanwhile, as the majority of operators was developing gas producers, others placed their faith in liquid fuels. The most common liquid fuel, of 1942, was alcohol. The quality ranged between 95 and 98 per cent. pure (the rest
being water), and performance varied accordingly. A typical performance would produce a consumption of five miles per Imperial gallon, with, say, a 60 per cent, power output, whereas, under similar, conditions, a machine running on petrol would give a return of 10 m.p.g. Modifications for this fuel consist mainly of drastically richening the mixture, advancing the ignition and raising the compression ratio. The last named was carried out by only a few owners, chiefly because of the practical difficulties of getting the alteration carried out. The typically optimistic outlook, which foresaw a day, in the not-too-distant future, when petrol would again be available, was another reason why operators did not do this.
Another interesting fuel was that obtained from wood and known as T'ong Yu, which I assume to have an ethyl alcohol base, although sludge, twigs and an acid content seemed to suggest that purifying methods could be improved. As in the case of neat alcohol the carburetter mixture is richened, although not quite to the same extent. Performance and consumption are barely 60 per cent, as efficient as when running on mineral petrol, starting is difficult, and the impurities are considerable, although much to be preferred to the dirt, drudgery and despair that accompany charcoal burning.
It was, of course, when petrol supplies were stopped that owners of oilers came into their own. Not only could they make more economical use of any stored, imported fuel than could the owners of a petrol fleet, but 'there was already being produced in China a fuel for their use. In Kansu Province there is a wealth of mineral oil, the exploitation of 'which has been on only a small scale, but chiefly in the production of oil' fuels. The performance on Kansu mineral oil at low altitudes and in warm temperatures compares favourably with that on imported Burma oil, although starting difficulties are introduced, and there is a noticeable loss of power•in the cold, higher regions.
Distribution of Kansu oil is such that stocks can be purchased at only one or two of the biggest cities in Free .China, or at the considerably reduced cost of about 10s. per gallon at the wells.
There is also at the disposal of the oil-engined-vehicle owner a fuel with the same base as T'ong Yu (wood oil) " petrol," although the performance is not very favourable and, as with the " petrol," impurities cause considerable havoc with precision components of the oil engine.
Finally, there is the refined fuel produced from the Kansu wells in China itself. Until late in 1942 probably less than 1 per cent, of the vehicles in China used it, but since then production has been considerably increased. This mineral product is used in unmodified petrol-engined lorries and gives a performance in the neighbourhood of 80 per cent. of that of imported petrol. Due to lack of equipment the fuel is not so good as it might be, and there is a tendency for unburnt fuel to cause dilution of the lubricating oil, but this disadvantage is not enough to prevent Kansu fuel from giving considerably better results than any other substitute fuels at present in use in China.
The point of topical interest in connection with all this is that, with the recent attacks on Myitk-ina, it would seem fairly reasonable to look forward to a time when a land mute will again be opened through the North of Burma and, in some degree, at any rate, the burden of making-do will be lifted from the shoulders of China's transporteers.'
M.D.