416 



NATURE 



[January 23, [919 



[ifficulties which will require much patience, greal 

 courage, untiring effort, and a fine spiril oi sacrifice 

 on the pari oi the community to realise. Yet the 

 reward will be great. There will need to be the 

 closes) co-operation among educational authorities to 

 give the requirements of the Act their full effect, and 

 they can only be solved painfully step by step. The 

 supply of suitable teachers is in itself a vast problem, 

 as well a-, the provision of appropriate buildings. The 

 it "i the hours of instruction so as to meet 

 the necessities of the various industries is scarcely 

 li ss perplexing. In many cases it must be met in 

 talcing the whole of a working day or more per week 

 for a limited period, and in rural areas Buring some 

 weeks of the winter season. Indeed, it will be seen 

 that no greater step was taken during the great war 

 towards peace-time 1 econstruction, seeing that the 

 Education Act, worked to its logical limit, means re- 

 ci msti u'ction all round. 



THE PRODUCTION OF OIL FROM 

 MINER !/. SOURCES. 1 



MANY and verj various products can be obtained 

 by tin carbonisation of bituminous minerals, the 

 character and quality of the materials produced depend- 

 ing mainly upon the temperature at which the process 

 is conducted. It does not, however, follow that all 

 identical products will be obtained from different bitu- 

 minous materials when the)' are subjected to the same 

 temperature conditions, because the chemical composi- 

 tion varies, and consequently when subjected to heat the 

 method of decomposition also varies. The organic body 

 or bodies in shale are called kerogen,and this, on being 

 subjected to moderate heat, yields oil of the define 

 and paraffin series, ammonia also being produced. 

 The organic matter in coals and cannels is generally 

 described as volatile mallei-, and probably differs con- 

 siderably in chemical character from the kerogen ; 

 consequently, on being subjected to moderate heat, 

 different products are obtained, although they also 

 are mainly of the define and paraffin series. When 

 coals are subjected to high temperatures a different 

 class of hydrocarbon is produced, mainly the hydro- 

 carbons of the benzene series. It is probable that 

 this would also be the case to a greater or less extent 

 if shale were also subjected to high temperature in 

 retorts similar to those employed for heating coal. 



It is extremely difficult to obtain an even distribu- 

 tion of heat in any carbonisation process ; consequently 

 it is bv no means eas\ to make certain of always 

 obtaining the same products from a given material 

 in the same proportions, and great care has to be 

 exercised to ensure that the conditions are as nearly 

 constant as possible. The form of the retort has 

 much to do with the quantity and quality of the pro- 

 ducts obtained. In all cases the first effect of the 

 heat is low-temperature distillation, because the 

 material is introduced cold into the retort, and, how- 

 ever high the temperature of the retort, the heat must 

 first gel through the badly conducting mass before the 

 temperatures can approximate to that of the retort, 

 and by that time a considerable part of the volatile 

 matter will have been driven off. Then another ques- 

 tion arises, viz. whether the form of the retort is such 

 that the volatile products, as they are formed, come 

 in contact with the surface of the retort before being 

 drawn off, or whether tbev are removed without being 

 heated after they have been evpelled from the material. 

 The quality and character of (be final products depend 

 almost entirely upon this. Tims in horizontal gas 

 retorts the volatile matter as it leaves the coal cones 



1 Abstract of a paper read before the Institution of Petroleum Technolo- 

 gists on December 17, 1918, by Dr. F. Mollwo Perlcin. 



NO. 2569, VOL. I02] 



ict with the highly heated arch and sides of 

 the retort before it enters the ascension pipes and is 

 carried to the hydraulic main. This causes radical 

 changes in the volatile products, and hydrocarbons of 

 1 In in 11/enoid or aromatic series are largely produced. 

 'in tin other hand, in a vertical retort tie volatile 

 products, as they are released from tin- .,..11. ascend 



upwards through the cold incoming coal, onl 

 lion 1 oming in contact with the hot walls of the retort, 

 and, as a consequence, the resulting products con- 

 tain a considerable proportion of Iixdnn , \„, 

 paraflinoid nature. 



Whether high or low temperature should be em- 

 ployed for carbonising bituminous material entire! 

 depends upon what products are required. For 

 works, where a large-volume yield of gas is required, 

 high temperature is essential, but where motor spirit, 

 Fuel oil, lubricating oil, and paraffin wax are required, 

 low-temperature carbonisation must be adopted. In 

 low-temperature carbonisation the gas pr6duced is lis, 

 than half that obtained by high-temperature carbonisa- 

 tion, and contains less hydrogen and more hydro- 

 carbons than the latter; low-temperature carbonisation 

 could, therefore, not be employed for the manufacture 

 of gas for lighting purposes. The main distinctions 

 between high and low temperature are as follows : — 

 High Temperature. 1 emperature. 



(a) Large volume of Low volume of gas, 

 gas, say 12,000 cu. ft. on say 5000 cu. ft. on the 

 the average. average. 



(6) Yield of sulphate of Yield of sulphate of 

 ammonia, on average, ammonia, on average, 

 say, 20 lb. say, 10 lb. 



(c) Yield of tar on Yield of tar (crude oil) 

 average, say, 11 gallons on average, say, 20 gal- 

 per ton of coal carbonised. Ions per ton of coal car- 

 bonised. 



(d) Tar is largely of Tar (crude oil) consists 

 aromatic series, and of hydrocarbons of the 

 yields benzol, toluol, aliphatic series (paraffins, 

 naphthalene, anthracene, olefines, and naphthenes). 

 carbolic acid, and cresols. From the tar can be ob- 

 These are the raw pro- tained motor spirit, fuel 

 ducts for the manufacture oil, lubricating oil, and 

 of dyes, explosives, photo- paraffin wax. The tar 

 graphic chemicals, drugs, acids are useful for dis- 

 and many other synthetic infectants, but of no 

 products. use as raw products for 



other industrial purposes. 



It should be mentioned that when coals high in 

 volatile elements and rich cannels are subjected to 

 low-temperature distillation, much larger yields of 

 crude oil are obtained, as much as 40 and 60 gallons. 



Oils obtained by the carbonisation of bituminous 

 material come under the same category as natural 

 oils ; they may, therefore, be classed as mineral oils, 

 even although their origin was probably organii :, 

 was that of natural oils, but many organic substani es, 

 such, for example, as peat or wood, will give oils of 

 a similar character when carbonised under suitable 

 conditions. 



At the outbreak of the war the world's production 

 of natural oil was in the neighbourhood of 50,0m 

 tons, and last vear more than 60,000,000 tons. 



Before the war Greal Britain was, with tin- excep- 

 tion of the oil obtained from the Scottish shale-oil 

 industry (275,000 tons crude oil), entirely dependent 

 upon imported oil for all the various purposes for 

 which oil is required. Our aeroplanes, warships, 

 motor-cars, etc., wen dependent upon sea transport 

 for petrol and fuel oil, and our machinery for lubri- 

 cants. l"n fortunately, we are still in the same posi- 

 tion. Great Britain, with her vast Navy and her great 



