Bathgate Chemical Works

From:

THE INDUSTRIES OF SCOTLAND – Their Rise, Progress and Present Condition

by David Bremner

This work appeared as a series of articles in the Scotsman in 1868.  It was then published by Adam and Charles Black in 1869. The visit to Bathgate is not dated but was probably made in 1867.

p482  MANUFACTURE OF MINERAL OILS AND PARAFFIN

David Bremner describes his visit to Bathgate Chemical Works:

In the year 1847 Professor Lyon Playfair, while visiting a brother-in-law who owned a coal-pit at [Riddings] Alfreton, Derbyshire, had his attention drawn to a thick, dark, oily fluid which trickled from rents in the roof of the colliery, and was struck by the idea that it might be transformed into some useful substance by proper chemical treatment. He imparted his views to Mr James Young, then a well-known chemist in Manchester, and suggested to that gentleman the advisability of subjecting the crude liquor to chemical investigation, with the view of testing the qualities it possessed. Mr Young took the hint, and found that the crude fluid on being distilled, yielded a pale yellow oil and contained floating particles of lustrous matter, which proved to be crystals of paraffin. Soon afterwards a factory for the distillation of burning and lubricating oils from the crude petroleum of the coal-mine was established at Alfreton by Mr Young. The enterprise was successful…but the factory had not been in operation for two years when the supply of raw material ceased…[Young then set himself to investigate the origin of the oil.] Guided by experience, he was led to the conclusion that the oil had its origin in the distillation of coal by subterranean heat. In the course of two years he was enabled to prove the correctness of the opinion he had formed. He found that,  by distilling coal at a low temperature, he obtained a liquid of oleaginous kind, similar in its virtue and consistency to the natural oil…Subsequent experiments proved that the crude oil could be extracted from any coal of a bituminous nature, and that the largest quantity could be obtained from cannel coal. …

Some bituminous coal obtained from Boghead, near Bathgate, in the county of Linlithgow, was tried by Mr Young in 1850, and found to be particularly rich in oil. As the supply was abundant, Mr Young   after taking out a patent for “treating bituminous coal to obtain paraffin and oil containing paraffin,” was joined by Messrs Meldrum & Binney. They selected a site near the town of Bathgate, and erected thereon an extensive establishment for extracting oil from coal, and converting it into a variety of useful products. The works were put up under the superintendence of Mr Meldrum, and were conducted under his active management. [Production began in February, 1851.]

Such was the beginning of trade which speedily assumed great importance, and converted the quiet town of Bathgate into a great centre of industrial activity. The district was chiefly inhabited by hand-loom weavers, whose miserable earnings – in many cases not exceeding 4s. a-week – were barely sufficient to prevent starvation; and when the new field of labour was opened up, the weavers gladly relinquished their looms, and sought employment at the paraffin works.  A proof of the marvellous success that attended Mr Young’s enterprise, and the deep hold that it took on the district, is afforded by the fact that, though the population of the parish and town of Bathgate had increased by only from 2513 to 3341 between the years 1801 and 1851, the ten succeeding years witnessed an increase to 10,000. The manufactory was extended until it covered a great space of ground; and the value of its products was recognised throughout the world.

The Bathgate Chemical Works are situated about a mile from the town. They occupy twenty-five acres of ground, and are connected with the main lines of railway in the vicinity by branch lines… The various departments are admirably arranged, and the appliances in all are so completely adapted to their purpose that it is difficult to believe that the manufacture of paraffin is really only a thing of yesterday. [The view] reveals a series of  broad thoroughfares lined with retorts, stills, boilers, tanks, &c., some under iron roofs, and others exposed to the weather.

… the visitor must begin at the coal-breaking shed. The coal used is a hard, rusty-black-coloured mineral…[It is broken] into small pieces, which may be conveniently shovelled into the retorts.

Contiguous to the breaking shed, the retorts, which are 200 in number, are ranged in sets of four each. The retorts are simply vertical cast-iron pipes twelve feet in length and fourteen inches in diameter. Each set of four retorts is built into a furnace, the lower part of the pipes being embedded in brickwork, while several feet of the upper end are left free. The retorts have funnel-shaped tops, and are fitted with air-tight stoppers. The lower extremity projects downwards through the furnace into a pit filled with water, an arrangement which, while it effectively shuts out the air, admits of the exhausted cinder being withdrawn without interruption… the waste is withdrawn gradually, and

fresh coal is added. The portion of the pipe which passes through the furnace is maintained at a dull red heat, and that is the point at which the distillation actually takes place. Under the influence of the fire, the coal is decomposed, the oil being driven off in the form of vapour, which is collected in a large main pipe having a connection with all the retorts. This main pipe conveys the oil vapour to the condensers, which are similar to those used in gas-works. The condensers stand outside, and, as the vapour passes through them, it is reduced to a liquid form. It is always found that a portion of the vapour is incondensable, and that portion is collected in a gas-holder, and is used for lighting the workshops. [It is vital that temperatures are strictly controlled to obtain the maximum amount of oil and the minimum amount of gas.] The liquid formed in the condensers is run off into a reservoir capable of containing 100,000 gallons. At this stage the oil has a black greasy appearance, like natural rock-oil or petroleum, and gives off inflammable vapours at the usual atmospheric temperature. The tank is fitted with an air-tight covering of iron for the purpose of retaining this vapour, and lessening the chances of ignition. Another precaution against loss by fire consists of a large pipe inserted into the roof of the tank, and so arranged that, in the event of the oil taking fire, a strong jet of steam could be at once sent in, and the flames be thus extinguished.

The crude oil obtained by distilling the coal is subjected to various other processes, under which it yields four different products – namely, paraffin oil for burning, paraffin oil for lubricating machinery, a light volatile fluid called naphtha, and solid paraffin; but before any separation of these takes place, the oil has to be thoroughly purified. It is first distilled, which is performed in a range of huge cylindrical stills, laid in a horizontal position. When the vapour from the stills is condensed, it is collected in tanks, and presents a wonderful improvement in appearance. The black sluggish stuff from the stock-tank has been converted to a dark-green limpid fluid. The impurities extracted from the crude oil are removed from the still after each charge. They form a large black lustrous substance, resembling coke, and make excellent fuel. Though much improved by the distillation, the oil is not yet sufficiently pure, and requires further treatment. It is run into circular iron tanks; and, after a certain quantity of sulphuric acid is added, the liquid is violently agitated by a revolving stirrer. The acid has no affinity for the finer oil, but it has for the foreign substances which the oil holds in solution. At the end of four hours’ agitation, the oil is seen to have a pale green colour; and on the liquid being allowed to settle, the vitriol and the organic impurities, by reason of their greater weight, collect in the bottom of the tank, and, when drawn off, this sediment is used for fuel. The oil is next transferred to a clean set of tanks, in which it is mixed with a strong solution of caustic soda, and again subjected to agitation. The soda neutralises any sulphuric acid that may remain in the oil, and rids it of impurities which were not affected by the vitriol. The oil is then distilled a second time, and the treatment with sulphuric acid and soda is repeated. After these operations, the oil presents a clear, pale, yellow colour and in that condition it contains the elements of the four products mentioned above. To separate these, and make them available, is the next care of the oil-makers. This is accomplished by distilling the oil at various temperatures.

The first product taken off is naphtha, for the separation of which only a gentle heat is required.

Naptha is a valuable liquid, extensively employed in the arts, and as an illuminator. By raising the temperature of the stills after the naphtha vapour has passed off, paraffin oil is obtained. Before being ready for the market, both the naphtha and the oil are distilled separately, in order to make them perfectly pure. The oil is the most valuable and important of all the articles manufactured at Bathgate, and is extensively known for its illuminating qualities. In country districts, where gas is not manufactured, the paraffin oil has almost entirely superseded the other kinds of oil, and is universally admired for the clearness and brilliancy of the light which it affords… Another, and not the least important virtue which which paraffin oil possesses, is the safety with which it can be used for domestic purposes. Great care is taken to separate the least trace of naphtha from it, so there is no risk of  explosion by accidental ignition.

When all the finer oil has been distilled over, the heat is increased, and the heavier vapour   is driven off. This last produces a thick oil, which, when thoroughly cooled, assumes the consistency of grease. It is in reality a mixture of oil and solid paraffin. When the paraffin has been crystallised by cooling the liquid, it is separated from the oil by a process of filtration under pressure.  The heavy oleaginous liquid is put into strong canvas bags, and these are placed in the  hydraulic presses, and squeezed until all the oil is forced through the texture of the bags. The oil extracted in this way is an excellent fluid for lubricating machinery, and is used in cotton mills and other establishments in which machinery of a delicate kind is employed. Two valuable peculiarities of this oil are that it does not become rancid, and that it is free from all tendency to spontaneous combustion.

The solid paraffin is now the only substance left. After the oil is extracted, the paraffin is emptied out of the bags. It is then of a dirty-yellow colour, and requires a deal of purification before it assumes that beautiful wax-like appearance by which it is distinguished. The stuff is placed in iron vessels containing heated naphtha, by which it is dissolved. The naphtha acts on the impurities, and after a certain time the liquid is allowed to cool, when it again assumes a degree of consistency. It is then subjected to filtration in canvas bags as before. This operation of dissolving the paraffin in naphtha, cooling it, and filtering through bags is repeated until the substance has acquired the requisite whiteness and purity. On being taken from the filters for the last time, the paraffin is removed to a workshop in which it is subjected to the action of steam, which carries off the odour of the naphtha; and the paraffin, in a liquid state, is run into circular iron moulds, in which it solidifies. As thus finally purified and crystallised, the paraffin is a fine white substance, more transparent than wax, and of a beautiful lustrous structure. It lacks both taste and smell, burns with a white flame, without smoke. Candles made of it are much in favour, both on account of the brilliant light they afford and the clearness with which they burn…

In the manufacture of paraffin, a great quantity of illuminating gas of a superior quality is produced. The town of Bathgate gets its supply from the Paraffin Works…

Additional notes :

James ‘Paraffin’ Young was born in Glasgow in 1811; he died at Inverkip in 1883. He studied at Andersonian College (now Strathclyde University) where his classmates included David Livingstone, Lyon Playfair, and Hugh Bartholomew. When Playfair’s brother-in-law, James Oakes, found the oil seepage [flow rate 300 gallons per day] at Riddings, Alfreton, Playfair was Professor of Chemistry in the Royal Institution, Manchester, and James Young, also  in Manchester, was working  for Charles Tenant & Company. When the oil seepage failed, Young looked for a coal from which he could extract oil and  Hugh Bartholomew, now manager of Glasgow Gas Works, send him samples of Boghead or Bathgate coal. This coal was formed from algae deposited in a lake and, being extremely rich in volatiles [liquids and gases which can be driven off by heat], it was a highly prized gas coal used in gas works throughout Scotland.

Frederick Penny, Professor of Chemistry, Andersonian University, Glasgow analysed Boghead coal  as evidence for the defenders in The Torbanehill Case of Gillespie v Russel. He found that about  70% [by weight] of Boghead coal consisted of ‘volatile matters’ and that one ton would produce 13,000 to 14,000 cubic feet of gas [370 – 400 cubic metres of gas]. H.M. Cadell in The Story of the Forth says ‘While the richest oil shales yield at most 35 to 45 gallons [160 – 200 litres] of crude oil per ton and have 70 to 75% of ash the Boghead Cannel or Torbanite produced 120 gallons [550 litres] or more of oil, and had not much more than 20% of ash.’ [The ash is inorganic residue. Carbon residue will burn so is not ash.]

Young produced lamps at the Clissold Lamp Works, New Spring Street, Birmingham.

To prevent possible competitors from finding out what was going on, the Chemical Works were set up and run under conditions of strict security. The Works were by surrounded by a high wall and workmen were sworn to secrecy. To mislead competitors, too, Young also used non-chemical names for his products; for example, lubricating oil was called ‘finished liquor’.

The Falkirk Herald of 9^th September, 1852, reported: These works have lately been erected at Boghead near Bathgate. They belong to Messrs. J. Young of Manchester; but being conducted strictly as a ‘secret work’ little is known in the district regarding the articles produced in them, and less of the means by which they are produced. Indeed all that is known on the subject, is that in them there is used large quantities of the Boghead cannel coal, from which it is understood that oil and various other valuable substances are, by some chemical process, extracted.