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Oil Refineries, Petrol and Fuel Oils

Several oil company railway tank liveries are illustrated below in the sub section on Oil Companies, lubricating and other specialist oil companies and tanks are discussed in 'Lineside Industries -Lubricating Oils & Associated Works', Bitumen companies and tanks are discussed in 'Lineside Industries - Bitumen', coal tar companies and tanks are described under 'Lineside Industries - Coal Tar Distillers' and seed crushing companies and tanks are illustrated in 'Lineside Industries - Industries associated with docks'. For more oil rail tank liveries see also 'Goods Stock - Rail Tanks' and 'Livery - Tank Wagons'.

In the present context it is possibly worth noting that several oil related locations such as oil storage depots and oil handling docks used 'fireless' locomotives (steam was pumped in to a specially constructed usually dome-ended 'boiler' and the loco used this to drive conventional pistons). These engines had no fire so no coal bunker or funnel and the pistons were often mounted at the cab end of the chassis.

Fig ___ Fireless locomotive

Sketch showing typical fireless locomotive

In the mid 1960s the Dingle Oil Jetty near Liverpool was still using a Barclay 0-6-0 fireless engine on this general type. By the 1980s diesel-hydraulic shunters were in common use, some being road-rail machines, based on (for example) the Unimog truck.

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Petroleum has been used for the last two thousand years, mainly as a 'lamp oil' and as a medicine. With the development of machinery it was also used as a lubricant but 'refining' was primitive and there was no real market for petrol or fuel oil until the 1880s when the internal combustion engine became popular.

In British law (as per the Petroleum Act 1871 et seq, the term 'petroleum' refers to 'Any rock-oil, Rangoon-oil, Burma Oil, oil made from petroleum, coal, schist, shale, peat or other bituminous substance and any products of petroleum or of any of the above mentioned oils, such as; Benzene, benzol, benzolene, diesel oil, fuel oil, gasoline, kerosene (paraffin), lythene, naphtha, petrol, toluene, turpentine etc'. These are then subdivided for various purposes by their respective 'flash point' (the temperature at which they will catch fire). There are various systems of division, ships use several categories but on the railways they have just three. Anything with a flash point below 73 deg.F. (23 deg.C.) is considered dangerous, those with a flash point above 73 deg F. but below 141 deg. F(60 deg C.) are considered worrisome and those with a higher flashpoint are considered safe. A fairly lengthy list of liquids falling into these categories has been included in the section on 'Livery - Tank wagon liveries', for this section only those likely to be encountered in connection with oil refineries are considered.

The more dangerous liquids such as petrol, gasoline, benzene, benzol, benzolene, methyl alcohol and methylated spirit) were required to have specially built Class A tank wagons, painted in a distinctive livery. These were not allowed to have bottom discharge after 1905 so there should be no valve stub on the top of these tanks. Less dangerous liquids such as paraffin (kerosene), mineral oil, shale oil, turpentine, white spirit and coal tar required special Class B wagons again in a distinctive livery. These did use bottom discharge and hence did have a valve spindle sticking up beside the filling hatch.

Class A tanks, after 1909, has a 'stone' coloured tank with a red band extending along the sides and across the ends. Class B tanks were to have a red body, but in practice heavy fuel oil and bitumen made black the only practical colour for wagons carrying them. In 1939 the red band on Class A wagons could have a gap in the centre but the solebar had to be painted red. During the 39-45 war Class A tanks were either grey or two-tone grey camouflage. After the war the red band was discontinued, tanks could be stone (rarely used) grey or silver and the sole bars had to be red.

Non dangerous liquids such as Bitumen, heavy fuel oil and lubricating oils have high flash points, but on the railways the first two were always transported in Class B wagons in with black painted tanks. Lubricating oil tanks sometimes used odd liveries (notably yellow tanks with red lettering used by Shell), but that was very much the exception rather than the rule and most had the standard Class B red oxide tanks.

In Britain the main market was initially for paraffin or kerosene for use in oil lamps and lubricating oils for the factories. Up to about 1900 the British used oil recovered from shale (sometimes encountered in coal mines) and imported more from the USA in barrels. The paraffin was then distributed either in the barrels or in small portable tanks and was retailed by ironmongers and hawkers who also sold the lamps and stoves which burnt it. The development of gas supplies and later electricity supplies reduced demand but oil lamps remained common into the 1920s. In the towns and cities paraffin heaters remained common and the 'paraffin man' with a tank on a hand cart or horse drawn cart remained a feature of life into the 1950s. In the country areas the oil lamps remained common into the 1930s as few farms had electricity or gas supplies (one common cargo in these area was wooden boxes with supplies of the glass funnels for oil lamps as people turned them up too high and the glass cracked).

Lubricating oil formed a separate market, being sold and distributed by companies established in the business of selling lubricating oil of vegetable origin before the introduction of mineral products.

After the introduction of the internal combustion engine in 1885, petrol came to be sold by chemists, paraffin sellers and (as a side line) by cycle repairers, who in time also undertook the sale and repair of motor cycles and motor cars (most of the British motor car manufacturers started out making bicycles). Prior to the 1890s most petrol was sold from a small tank, the customer providing the container to take it away in. In the 1890s Russian oil arrived, by 1900 about a third of the oil sold in the UK was from Russia, the bulk of the rest being from American oil wells. In 1890 Anglo-American (better known today as Esso) introduced a sealed two gallon petrol tin (which reassured the purchaser that the oil had not been watered down with an inferior grade). The two gallon tin proved popular and became the most popular method for selling petrol for the next 20 years.

By the time of the First World War most oil arrived in bulk tanker ships (Shell had a lot to do with developing this), the demand had grown and companies had set up ever larger storage and distribution depots all over the country. Very little oil was refined in the UK, the refineries at the time were close to the well, so the cargo on the ships was the high value product rather than the low value crude oil.

Petroleum oil of various grades has been a regular cargo on the railways since the mid nineteenth century, initially transported in wooden barrels later and (by the time of the First World War) two gallon tins and rolled steel drums. Tank wagons were introduced in limited number from the mid 19th century, however these could only operate between locations equipped to handle bulk oil, so were not terribly common until the 1920s. Up to the mid 1930s most petrol was sold in 2 gallon tins, introduced by the Americans, these were transported in vans. They were packed in open wooden crates of two tins for shipping as they could not otherwise be stacked because the handle and filling cap stuck up on the top. The two gallon tins remained in civilian use into World War Two, although as more retailers invested in tanks and pumps bulk tanker supplies were delivered. The British and American military in particular were dependent upon the two gallon tin for forward supplies, two tins in a crate was a convenient size for man-handling. during the war the 5 gallon German 'jerry can' found favour as it was made of thicker steel, could be packed more densely and could be stacked without a crate round it. By the end of the war the Allied forces had changed over to jerry can, although these were not perfect, more than one Stalwart load carrier caught fire in the 1960s and 70s when petrol from a leaking jerry can reached the hot exhaust.

Pipelines are cheaper than rail transport but cost a lot to build. The government built a pipeline system to supply oil products to military establishments in the 1930s, this remains operational today and private companies can also use it. During the invasion of Europe in 1944 this pipeline supplied the Pluto cross-channel pipeline to supply the troops with fuel. In 1969 the privately owned United Kingdom Oil Pipeline (UKOP) was opened, originally to connect the Shell refineries at Stanlow and at Shell Haven on the Thames Estuary. It has since been further extended and also supplied Nottingham and Northampton terminals. Quite early on someone discovered that you could feed one grade after another up a pipeline with very little mixing of the two grades, hence only a single pipeline is needed to carry a wide range of products.

In the 19th and early 20th Century the UK relied on imported refined oils, when demand increased in Scotland at the start of the 20th century the Anglo-Saxon Petroleum Co. Ltd. built a storage facility at Granton Docks (Edinburgh), to which the petrol and other oils were transported in tank barges towed across from refineries which had been established in Rotterdam. Granton was where, in 1850, the world's first train-ferry operated, using a paddle steamer, between Granton and Burntisland (Fife). The service ended in 1890 when the Forth Bridge opened.

Within a few years the Scottish distributor found they needed a better supply and added facilities for ocean going tankers on one of the quays at the main harbour and pipelines up to the storage tanks. By this time a typical deep-sea tanker was about two hundred and fifty feet long, which is about 20 inches in British N, 40 inches in OO. This site supplied most of Scotland's oil fuels for many years (I think it closed in the early 1970s, but I am not at all sure on that). By the 1950s the site was jointly owned by Scottish Oils (a BP subsidiary) and Shell-Mex Ltd but was still reliant on imported refined products (although regular rail shipments were received from other UK facilities).

By the time of the First World War the UK had some limited refinery capacity, however Shell had to dismantle a refinery designed to recover toluene (vital in explosives manufacture) which they had built in Holland and ship it back to the UK. This was set up at Portishead and made a seriously important contribution to the war effort.

Some sources claim that the first UK refinery to process imported crude oil was at Llandarcy near Swansea, which opened in 1928 (closing in the later 1990s), however the APOC refinery at Grangemouth opened in 1924 (although that may have been dealing with imported partly refined oils), Fawley refinery was built in 1920/21 by Anglo Gulf West Indies Petroleum Corporation Ltd but again this may simply have been reprocessing the refined products of crude oil imported from the massive refineries in Holland. Prior to the 1920s the principal (and possibly only) general petroleum refining in the UK was the processing of 'shale oil' (discussed in more detail below) mainly for use as a lamp oil and for 'medicinal purposes'.

By the later 1920s several British oil refineries were refining crude oil and marketing a full range of petroleum products within the United Kingdom including retail motor oil and lubricants. The range of products produced included industrial lubricants, fuel oil for power stations and small quantities of oil derivatives for highly specialised uses. By the 1930s 'petrochemicals' were becoming increasingly significant part of the refinery business (these are discussed in more detail separately).

There are only a few refineries in the UK, the more modern post-war examples tend to be clustered together around the ports however there have always been a number of smaller refineries dotted about the place. All larger refineries are rail connected, there have been a very few small refineries which were not. If modelling a refinery you only need the rail access area, the bulk of the establishment should be on the backscene.

From the refinery the products are shipped (by road, rail, boat or pipeline) to 'distribution depots' where it is loaded into drums or tankers for delivery to customer. These depots do not as a rule engage in further processing of the product and from a modelling perspective offer several advantages over a 'refinery' for a line side industry. All that is required is the suggestion of some storage tanks and a discharge point for the tankers.

Refining Oil

As it comes out of the ground oil is made up of a range of materials ranging from heavy tar to oils so light they will evaporate, this raw mix is of limited practical use. In a refinery the various grades of oil are separated, each being used for particular purposes.

In the 18th and early 19th century the most saleable commodity from mineral oil was paraffin (also known as kerosene), widely used for 'oil lamps' and heating and later for 'paraffin engines' (for which one manufacturer (Kelvin) suggested that Russian oil is the best, but all Russian oil is not alike, good oil is also produced in Scotland but American oil is unsuitable). In the 1920s major paraffin suppliers included Shell Mex Ltd., the Anglo-Persian Oil Co., Ltd, The Scottish Oil Agency, Ltd., The Pinkston Oil Co. of Glasgow, and the The Merchant Trading Co. of London. I believe only the first three manufactured paraffin, the remainder importing their supplies. Paraffin is technically a Class B cargo but was also seen carried in Class A wagons (it is comparatively clean and does not stain everything black).

In the early days of the industry (around the mid 19th century) the simple fractional distillation process then used on the crude oil gave four products: benzene marketed as a cleaning product for leather and furniture, kerosene for burning in lamps and stoves, paraffin wax for candle manufacture and a heavy waste oil for which there was no immediate use. Petrochemicals cam in during the 1920s, following the first production of rubbing alcohol, or isopropyl alcohol, by Jersey Standard in 1920. Petrochemicals are discussed in more detail separately.

The sulphur removed from the oil is sold or made into sulphuric acid (actually it leaves the refinery as oleum, or sulphur tri-oxide as either a solid or liquid depending on the exact formulation, just add water to get sulphuric acid). Sulphur and sulphuric acid are both valuable industrial chemicals. Paraffin wax is another valuable material with a surprising range of applications (including frozen food packaging).

The thick residue left after removal of the more valuable materials is known as residual bitumen (to distinguish it from naturally occurring 'crude bitumen'). This is used to make tarred road surfaces (mixed with limestone or granite chippings it is called asphalt) and also as a waterproofing for wood or felt roofing material. Just to confuse matters the Americans refer to bitumen as asphalt. Bitumen has largely replaced coal tar in these duties, which is handy as the coal gas plants and steel works (both large producers of coal tar) have now all but disappeared. However with the concern over oil supplies bitumen is now being made from non-petroleum based renewable resources (developed in America and hence called bioasphalt). A by product of the bitumen processing is petroleum coke (usually called petcoke) which is basically carbon and is used for making electrodes and as a fuel (although it has a high sulphur content so it is not used for domestic purposes).

Finally a range of useful gasses are produced, these are generally referred to as Liquid Petroleum Gas or LPG. Most of these gasses can be conveniently liquified and shipped at moderate pressures. They were first produced in 1910 by Dr. Walter Snelling, and the first commercial products appeared in on the market in 1912. A proportion of these gasses are used raw as fuel at the plant, when it is known as 'process gas'. The remainder is split into its component parts, mainly Butane, Propane and Ammonia for sale. Other chemicals can be recovered from the LPG, notably Propylene and butylenes, used in the production of a number of plastics.

A full blown oil refinery is a large installation characterised by numbers of storage tanks, a cluster of tall metal towers, cooling towers and a lot of pipe-work. There will also be a number of buildings, some housing processes other housing offices and laboratories. The attraction for the modeller is the range of rolling stock which would be required to handle the various petrochemicals produced. Refineries are impressive, modelled well they can be very impressive and it is perhaps worth noting that chemical plants (discussed separately) often use similar processing methods and plant but these can be very much smaller. There were also a number of rather small refineries, in the main these re-processed the materials from the oil refinery, an example being the Briggs refinery in Dundee which in later years 'cracked' the thick bituminous residue from the refineries to extract saleable fractions. These smaller establishments received their supplies by rail as well as shipping out their products.

A refinery is more a finely balanced machine than a factory as so much of what happens depends on other parts of the system functioning. Crude oil flows in at one end, this is split into its components and these are then further processed to produce saleable materials. Many of the various processes require a constant flow through the system, when something has to be maintained and no back-up is available a series of buffer tanks are used to allow the remainder of the system to continue. If a refinery has to be shut down (which can take weeks to do properly) it can be a year or more before it can be re-started.

The tall metal towers are where the initial refining takes place. The crude oil is first heated and fed into a 'fractionating column', basically a large condenser in which the different grades are condensed out at different levels, the heavier bituminous tars and oils at the bottom, and progressively lighter more volatile products; paraffin wax, lubricating oil, gas oil, motor and aviation spirit (petrol) towards the top and gasses are taken off right at the top of the tower. There are often two of these towers, the second operating in a partial vacuum in order to get a better separation of the fractions. In the illustration below the two columns can be seen on the right of the installation, there are also three thinner columns to the left.

Fig ___ Fractionating column

Sketch showing Fractionating column with products associated with an oil refinery

Over the years the design of these towers has evolved, prior to World War Two the towers tended to be encased in girderwork and had a greater number of access platforms. This type is illustrated and discussed under Modelling Refineries below

As the demand for the lighter spirits is high the heavy oils are further refined in 'cracking towers', where a heat treatment breaks down the liquid, pressurised to raise its boiling point, into a series of lighter products. The cracking process was originally developed in the later 19th century (in America and Russia), it allowed the production of high octane fuels but the oil companies decided against using it at the time due to the cost of the additional plant (they thought there was perhaps 25 years worth of petrol in the world, this was before the discovery of the Middle Eastern oil fields). The the modern cracking methodology was developed in the early 1930's by an American called Eugene Houndry (1892-1962) and arrived in Britain shortly thereafter. At the time the British oil industry was still importing most of its oils as already refined products, only after World War two did the government encourage the building of refineries to import low value 'crude', refining it in the UK and selling the high value products. The cracking process has been further refined and modern systems use a powdered catalyst as a 'fluidised bed' through with the gasses are passed, first developed in 1944 this is usually called an FCC plant for fluid catalytic cracking. I believe the three towers on the left in the illustration above are 'cracking' towers.

From the early 1950s several refineries set up chemicals units to manufacture alkylbenzenes, the basis of household detergents.

Fig ___ View of the ConocoPhillips refinery, Humberside

Photo of the CobocoPhillips refinery at Humberside

Image copyright and courtesy of ConocoPhillips

Note that pipework in a refinery is almost always raised, where it runs beside a road it is typically to chest height but in crowded areas there is room to walk underneath. Raised pipes allow spills and leaks to be quickly spotted and metal trays can be placed under them until a repair can be effected.

The products of the various distillations are not useable without further treatment, the distillates are commonly treated with sulphuric acid and caustic soda, when there is a lot of sulphur in the oil cupric oxide (a black solid material delivered as a crumbly loose solid) or litharge is employed as a desulphurizing agent. The acid and caustic soda are usually delivered as liquids in tanker wagons.

Petroleum oil processing developed after the advent of the railways, and the railways provided a convenient way of moving the product inland from the coastal refineries. Oil for British refineries (including refined products such as petrol) has always been imported and a number of large establishments equipped with storage tanks of various kinds have been operating since at least the early twentieth century (possibly earlier). The 'tank farms' associated with refineries tend to be rather large, just one of the refineries at Milford Haven has 145 storage tanks, 11 for crude oil delivered by the ships and the rest for the storage of petrol and other refined product.




Principal Oil Refining Areas

Due to the obvious danger of fire, and to save money on the purchase of land, oil depots were usually located outside built-up areas and tended to grow rather haphazardly as consumption for fuel and chemical industry feed-stock increased.

Because most oil is imported most oil refineries and associated petro-chemical establishments are located on large river estuaries. Generally they prefer flat land and they tend to need a lot of water for cooling purposes. Inland depots tended to be somewhat smaller but that is a relative term and they were still on the big side for inclusion on a model railway.

Fig ___ Major rail connected oil installations

Sketch map showing major rail connected oil installations in mainland Britain

As noted above however there were smaller refineries, such as the Briggs plant in Dundee, which further processed the refineries's waste products to extract saleable materials. These were often very small (compared to a full refinery), they often employed rail for both deliveries of the raw materials and shipping of the products. These small establishments represent the bridge between oil refineries and petrochemical plants.




British on-shore and off-shore oil fields

There are only limited deposits of (liquid) oil found in the UK mainland at East Nottinghamshire and in north Leicestershire, with a post war field at Wytch Farm Dorset. Oil shale (described below) was however a very significant source of certain oil products from the 1830s until after World War One (the last plants closing in the 1960s).

British Oil Shale Refining

Oil shale is a kind of rock which contains an oily liquid called kerogen which can be distilled to produce hydrocarbons similar to those in petroleum. Oil shale was regularly used from about the sixteenth century but this was mainly seen as a medicinal material. In the seventeenth century an Italian town was heated using gas made from oil shale but serious commercial exploitation only began in 1838 in France where the oil was distilled for lamp oil. If you heat oil shale to about 500 degrees Celsius you get hydrocarbons and a range of solid products most of the solids are useless but some are valuable, notably sulphur, ammonia, alumina, soda ash and nahcolite (which is used in industrial exhaust gas scrubbing).

By driving off the oil in retorts (similar in principle to those used in gas works) four types of oil could be recovered paraffin oil for burning, oil for lubricating machinery, a light volatile fluid called naphtha, and solid paraffin. The oil from the retorts was purified by mixing with sulphuric acid and allowing the acid to precipitate out the impurities. The waste material was sold as fuel (the acid was not recovered and would require regular shipments to replenish the stocks). Caustic soda was then mixed in to deal with any residual sulphuric acid and the entire process of distillation and purification was then repeated to produce the pure oils. Also produced were ammonia and ammonium sulphate (a fertilizer, sales of which kept the enterprise afloat in the early years).

Most people used whale oil for domestic lighting but by the mid nineteenth century whale oil could not meet the demand for lamp oil and prices rose. Around this time various shale oil recovery firms were established. You may see references to 'tar tunnels', these were usually coal mines which encountered a layer of oil rich coal (known as cannel) the liquid in which then leaked out and could be processed. The Ironbridge Gorge Museum complex in Shropshire includes a tar tunnel of this type.

James Young (1811-1883) was the originator of the British paraffin industry. In the later 1840's he was engaged in the manufacture of oils from a petroleum spring at Alfreton, Derbyshire, and in 1850 set up a partnership to manufacture oils from `Torbane Hill mineral', or `Boghead coal', at Bathgate. He began selling paraffin in 1856 and had a great deal of success with the product (which did not smell nearly as badly as the fish oils used in lamps). Young bought out his partners and sold the enterprise (`Young's Paraffin Light and Mineral Oil Company') in 1866. Carboniferous shale later replaced the coal and over the years the process was continuously adjusted to recover the most valuable components (at the expense of the less valuable products).

Many shale oil works failed at the end of the nineteenth century as comparatively cheap US and Middle Eastern oil came in to the UK, some firms adapted to the new oil and thrived (Walkers Century Oils in Stoke on Trent started refining shale oil in the 1870s but went on to become a major player in the UK lubricating oil business). Where the shale contained more than about five percent oil by volume recovery remained an economic proposition even after the advent of imported oil, this was mainly done by shifting the emphasis in production. For example as the Chillian guano reserves were used up in the later 19th century the shale was used to produce sulphate of ammonia fertiliser as well as oils. The shale oil refineries were quite large enterprises, several operated their own internal (narrow gauge) railways to bring the shale from the mines to the retorts, Andrew Barclay of Kilmarnock supplied at least three such engines to Young's works at Addiewell and Uphall. Shale oil was commercially refined in the Lothian area of Scotland (to the West of Edinburgh) from the 1860's until the 1960's and, on a smaller scale, in north Somerset near Watchet. At its peak, in 1913, the industry in Scotland employed over 10,000 people and that year extracted over three million tons of shale from the various mines in the area. At that time they could expect to get 30 gallons of oil per ton of shale, by the time the operation closed in 1962 they were managing only about 20 gallons per ton. The Scottish shale oil works used the Pumpherston process which employs external heating of the retort. The final types of retort used was developed around the time of the First World War, a tall vertical system using gravity to carry the shale down through the retort. In the Second World War manpower shortages saw all retorting concentrated at one plate (at Westwood). For a time in the early nineteenth century Britain was an oil exporting country but this did not last long and the vast majority of the UK's oil was imported prior to the North Sea oil boom of the late 1970's.
In the oil business oil from shale and tar sands is called syncrude. A 2005 estimate set the total world resources of oil shale at 411 gigatons — enough to yield 2.8 to 3.3 trillion barrels (520 km3) of shale oil. This exceeds the world's proven conventional oil reserves, estimated at 1.317 trillion barrels (209.4×10^9 m3), as of 1 January 2007. The United States, Russia and Brazil account for 86% of the world's resources in terms of shale-oil content with the US holding just over 60 percent.




Imported Oils

The British have to a large extent relied on imported oil for most of the 19th and 20th centuries. Early imports came from Baku (then in Russia now in Azerbaijan) where the stuff was close enough to the surface to be lifted out of holes dug in the ground. Oil was discovered in Burma in 1859, and the Burmah Oil Co was set up to exploit it. An American called Drake discovered Pennsylvanian crude oil in 1859 and the business expanded rapidly but as with most oils in the Western hemisphere the proportion of lighter fractions (kerosene, petrol, naphtha and diesel oils) was small. Oils from the Eastern hemisphere contain a higher proportion of the valuable light ingredients but less sulphur and thick residues such as asphalt and coke (which often contain metals). The heavy western oils need more energy input to break them down, typically to get two barrels of goodies from heavy oil you use one barrel of the oil as fuel. A light oil well produces about 10,000 barrels per day, heavy oil wells only deliver 5-100 barrels a day.

As result there were expeditions to various parts of the world and in the Middle East large deposits were found by British entrepreneurs, first in Iran (resulting the formation of the Anglo Persian Oil Company, now BP), then in Iraq and Kuwait. As a result the British had a considerable influence in that part of the world and by the later 19th century the UK was importing oil from this area in purpose built tanker ships (this was the basis of Shell's oil business in the early days). One of the reasons for tension between Britain and France and the Germans in the run up to World War One was the shift to oil fired warships, the Germans had no domestic oil production and were actually going to build a railway line from Berlin down to Basra in Iraq to bring oil for their fleet. The first (and one of the largest) deployments of British troops in World War One was in fact to Basra to secure the Iraqi oil fields. This was also part of the reason BP became so big, they offered guaranteed supplies to the Royal Navy in exchange for some investment by the government.

Until the end of the second world war the UK imported processed refinery products, mainly from the Western Hemisphere (ie the US and South America). By the end of 1938 some thirteen refineries in the United Kingdom were producing petrol, but the output represented less than 15 per cent of total deliveries to all home market consumers. In 1946 75 per cent of United Kingdom requirements for all petroleum products, including nearly 90 per cent of the petrol, were still imported in finished form. In the years which followed the 1939-1945 war, however, there was a shift from dollar countries to the Middle East as the main source of supply of crude oil for Western Europe. The leading oil companies in the United Kingdom were also encouraged by the Government to set up a number of new refineries and thereafter imports were increasingly in the form of crude oil rather than of finished products.

By 1963 nearly 70 per cent of all United Kingdom imports of crude oil came from the Middle East, about 11 per cent from Venezuela and a similar amount from North Africa (where oil had been struck for the first time in 1956).