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PETROLEUM (Lat. Petra, rock, and oleu...
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See also:PETROLEUM (See also:Lat. See also:Petra, See also:rock, and oleuin, oil)
, a See also:term which, in its widest sense, embraces the whole of the See also:hydrocarbons, gaseous, liquid and solid, occurring in nature (see See also:BITUMEN)
.
Here the application of the term is limited to the liquid which is so important an See also:article of See also:commerce, though references will also be made to natural See also:gas which accompanies See also:petroleum
.
Descriptions of the solid forms will be found in the articles on See also:asphalt or asphaltum, See also:albertite, See also:elaterite, See also:gilsonite, See also:hatchettite and See also:ozokerite
.
Particulars of the shales which yield oil on destructive See also:distillation are given in the article on See also:paraffin
.
See also:Ancient See also:History.—Petroleum was collected for use in the most remote ages of which we have any records
.
See also:Herodotus de-See also:scribes the oil pits near Ardericca (near See also:Babylon), and the See also:pitch See also:spring of Zacynthus (See also:Zante), whilst See also:Strabo, Dioscorides and See also:Pliny mention the use of the oil of See also:Agrigentum, in See also:Sicily, for See also:illumination, and See also:Plutarch refers to the petroleum found near See also:Ecbatana (See also:Kerkuk)
.
The ancient records of See also:China and See also:Japan are said to contain many allusions to the use of natural gas for See also:lighting and See also:heating
.
Petroleum (" burning See also:water ") was known in Japan in the 7th See also:century, whilst in See also:Europe the gas springs of the See also:north of See also:Italy led to the See also:adoption in 1226 by the See also:municipality of See also:Salsomaggiore of a See also:salamander surrounded by flames as its See also:emblem
.
Marco See also:Polo refers to the oil springs of See also:Baku towards the end of the 13th century; the medicinal proper-ties of the oil of See also:Tegernsee in See also:Bavaria gave it the name of " St See also:Quirinus's Oil " in 1436; the oil of Pechelbronn, Elsass, was discovered in 1498, and the " earthbalsam " of See also:Galicia was known in 15o6
.
The earliest mention of See also:American petroleum occurs in See also:Sir See also:Walter See also:Raleigh's See also:account of the See also:Trinidad pitch-See also:lake in 1595; whilst See also:thirty-seven years later, the account of a visit of a Franciscan, See also:Joseph de la See also:Roche d'Allion, to the oil springs of New See also:York was published in Sagard's Histoire du See also:Canada
.
In the 17th century, See also:
A See also:Russian traveller, See also:Peter Kalm, in his See also:work on See also:America, published in 1748, showed on a See also:map the oil springs of See also:Pennsylvania, and about the same See also:time Raicevich referred to the " liquid bitumen " of See also:Rumania
.
See also:Modern Development and See also:Industrial Progress.—The first commercial exploitation of importance appears to have been the distillation of the oil at See also:Alfreton in See also:Derbyshire by See also:
See also:Sumatra, See also:Java and See also:Borneo, where active development began in 1883, 1886 and 1896, bid See also:fair to See also:rank before See also:long among the See also:chief See also:sources of the oil supplies of the world
.
Similarly, Burma, where the Burmah Oil Company have, since 189o, rapidly extended their operations, is rising to a position of importance
.
Oil fields are being continually opened up in other parts of the
world, and whilst America still maintains her position as the deposited on See also:compression. largest petroleum producer, the world's supplies are now being derived from a steadily increasing number of centres
.
See also:Physical and Chemical Properties.—Although our See also:information respecting the chemical See also:composition of petroleum has been almost entirely gained since the See also:middle of the 18th century, a considerable amount of empirical knowledge of the substance was possessed by chemists at an earlier date, and there was much See also:speculation as to its origin
.
In his Sylva sylvarum (1627), See also:Francis See also:
This See also:report has become a classic in the literature of petroleum
.
The physical properties of petroleum vary greatly
.
The See also:colour ranges from See also:pale yellow through red and See also: It is found that transparent oils under the influence of light absorb oxygen, becoming deeper in colour and opalescent, while strong acidity and a penetrating odour are See also:developed, these changes being due to the formation of various See also:acid and phenylated compounds, which are also occasionally found in fresh oils . The residues from petroleum distillation have been shown to contain very dense solids and liquids of high specific gravity, having a large proportion of carbon and possessed of remarkable fluorescent properties . Natural gas is found to consist mainly of the See also:lower paraffins, with varying quantities of carbon dioxide, carbon monoxide, hydrogen, nitrogen and oxygen, in some cases also sulphuretted hydrogen and possibly See also:ammonia . This mixture dissolves in petroleum, escaping when the oil is stored, and conversely it invariably carries a certain amount of water and oil, which is Occurrence.—Bitumen is, in its various forms, one of the most widely-distributed of substances, occurring in strata of every See also:geological See also:age, from the lowest Archean rocks to those now in process of deposition, and in greater or less quantity throughout both hemispheres, from Spitzbergen to New See also:Zealand, and from California to Japan . The occurrence of commercially valuable petroleum is, however, comparatively limited, hitherto exploited deposits being confined to rocks younger than the See also:Cambrian and older than the See also:Quaternary, while the majority of developed oil-fields have been discovered north of the See also:equator . The See also:main requisites for a productive oil or gas field are a porous See also:reservoir and an impervious See also:cover . Thus, while the See also:mineral may be formed in a stratum other than that in which it is found, though in many cases it is indigenous to it, for the formation of a natural reservoir of the fluid (whether liquid or gas) it is necessary that there should be a suitable porous rock to contain it . Such a rock is typically exemplified by a coarse-grained See also:sandstone or See also:con-glomerate, while a See also:limestone may be naturally porous, or, like the Trenton limestone of See also:Ohio and See also:Indiana, rendered so by its See also:conversion into See also:dolomite and the consequent production of cavities due to shrinkage—a change occurring only in the purer limestones . Similarly it is necessary, in view of the hydrostatical relations of water and mineral oils, and the volatile character of the latter, that the porous stratum should be protected from water and See also:air by an overlying shale or other impervious See also:deposit . Water, often saline or sulphurous, is also found in these porous rocks and re-places the oil as the latter is withdrawn . In addition to these two necessary factors, structural conditions See also:play an important part in determining the See also:accumulation of oil and gas . The main supplies have been obtained from strata unbroken and comparatively undisturbed, but the occurrence of anticlinal or See also:terrace structure, however slightly marked or limited in extent, exerts a powerful influence on the creation of reservoirs of petroleum . These tectonic See also:arches often extend for long distances with great regularity, but are frequently crossed by subsidiary anticlines, which themselves play a not unimportant part in the See also:aggregation of the oil . Owing to difference of density the oil and water in the anticlines See also:separate into two layers, the upper consisting of oil which fills the anticlines, while the water remains in the synclines . Any gas which may be See also:present rises to the summits of the anticlines . When the slow folding of the strata is accompanied by a See also:gradual See also:local descent, a modified or " arrested " anticlinal structure, known as a " terrace " is produced, the up-heaving See also:action at that part being sufficient only to See also:arrest the descent which would otherwise occur . The terraces may thus be regarded as See also:flat and extended anticlines . They need not be See also:horizontal, and sometimes have a See also:dip of a few feet per mile, as in the See also:case of the Ohio and Indiana oil fields, where the amount varies from one to ten feet . These slight See also:differences in level, however, are found to have a most powerful effect in the direction already mentioned . It is evident that accurate knowledge of the character and structure of the rock-formations in petroliferous territories is of the greatest importance in enabling the See also:expert to select favourable sites for drilling operations; hence on well-conducted petroleum-properties it is now customary to See also:note the character and thickness of the strata perforated by the See also:drill, so that a See also:complete See also:section may be prepared from the recorded data . In some cases the depths are stated with reference to See also:sea-level, instead of being taken from the See also:surface, thus greatly facilitating the utilization of the records . Oil and gas are often met with in drilled See also:wells under great pressure, which is highest as a See also:rule in the deepest wells . The closed pressure in the Trenton limestone in Ohio and Indiana is about 200–300lb. per sq. in., although a much higher pressure has been registered in many wells . The gas wells of Pennsylvania indicate about See also:double the pressure of those drilled in the Trenton limestone, 600–800 lb. not being unusual, and even moo lb having been recorded . The extremely high pressure under which oil is met with in wells drilled in some parts of the Russian oil fields is a See also:matter of See also:common knowledge, and a See also:fountain or spouting well resulting therefrom is one of the " See also:sights" of the See also:country . A famous fountain in the See also:Groznyi oil field in the See also:northern See also:Caucasus, which began to flow in August 1895, was estimated to have thrown up during the first three days 1,200,000 poods (over 4,500,000 gallons, or about 18,500 tons) of oil a day . It flowed continuously, though in gradually diminishing quantity, for fifteen months; afterwards the flow became intermittent . In See also:April 1897 there was still an occasional outburst of oil and gas . Three theories have been propounded to account for this pressure:- 1 . That it results from the weight of the overlying strata . 2 . That it is due to water-pressure, as in artesian wells (" hydro-static " or " artesian " theory) . 3 . That it is caused by the compressed See also:condition of the gradually accumulating gas . Of these the first has been proved untenable, and while in some instances (e.g. certain wells in Ohio), the second has held See also:good, the third appears to be the most widely applicable . The conditions of formation and accumulation of petroleum point to the fact that the principal oil fields of the world are merely reservoirs, which will become exhausted in the course of years, as in the case of the decreasing yield of certain of the American fields .
But new deposits are continually being exploited, and there may be others as yet unknown, which would entirely alter any view that might be expressed at the present time in regard to the probable duration of the world's See also:supply of oil and gas
.
As already stated, every one of the great geological systems appears to have produced some See also:form of bitumen, and in the following table an See also:attempt has been made to classify on this basis the various localities in which petroleum or natural gas has been found in large or small quantities:
See also:Recent.—See also:Lancashire (Down See also: Carboniferous.—See also:Scotland, North of See also:England, and Midlands, Wales, France, See also:Belgium, See also:Carniola, Moravia, Elsass, Saxony, See also:Perm, Sizran, China, Cape Colony, Nova See also:Scotia, See also:Newfoundland, Pennsylvania, West Virginia, Ohio, See also:Michigan, Indiana, Illinois, See also:Iowa, See also:Missouri, See also:Tennessee, Kentucky, Alabama, Kansas, Arkansas Colorado, Oklahoma, See also:Tasmania, Victoria (Permo-Carboniferous), West Australia (Permo-Carboniferous) . Devonian.—Scotland, Devonshire, Spain, Hanover, See also:Archangel, See also:Vitebsk, Athabasca, See also:Mackenzie, See also:Ontario, See also:Quebec, New Brunswick, Newfoundland, New York, Pennsylvania, West Virginia, Ohio, Michigan, See also:Wisconsin, Kentucky . See also:Silurian.—Shropshire, Wales, Bohemia, Sweden, See also:Esthonia, Manitoba, Ontario, Quebec, Newfoundland, New York, Pennsylvania [?], Ohio, Michigan, Indiana, Illinois, Minnesota, Tennessee, Kentucky, See also:Georgia, Alabama, Oklahoma, New Mexico, New See also:Caledonia . Cambrian.—Shropshire, New York . Archean.—France, See also:Norway, Sweden, Ontario . In this list, while certain occurrences in rocks of undetermined age in little-known regions have been omitted, many of those included are of merely See also:academic See also:interest, and a still larger number indicate fields supplying at present only local needs . All have been arranged in See also:geographical See also:order without reference to productive capacity or importance . It should be pointed out that the deposits which have been hitherto of chief commercial importance occur in the old rocks (Carboniferous to Silurian) on the one hand, and in the comparatively new See also:Tertiary formations on the other, the intermediate periods yielding but little or at any rate far less abundantly . Origin.—The question of the origin of petroleum (and natural gas), though for the first See also:half of the 19th century of little more than academic interest, has engaged the See also:attention of naturalists and others for over a See also:hundred years . As early as 1804, See also:Humboldt expressed the See also:opinion that petroleum was produced by distillation from deep-seated strata, and Karl See also:Reichenbach in 1834, suggested that it was derived from the action of heat on the See also:turpentine of See also:pine-trees, whilst See also:Brunet, in 1838, adumbrated a similar theory of origin on the ground of certain laboratory experiments . The theories propounded may be divided into two See also:groups, namely, those ascribing to petroleum an inorganic origin, and those which regard it as the result of the decomposition of organic matter . M . P . E . See also:Berthelot was the first to suggest, in 1866, after con-ducting a See also:series of experiments, that mineral oil was produced by purely chemical action, similar to that employed in the manufacture of acetylene . Other theories of a like nature were brought forward by various chemists, Mendeleeff, for example, ascribing the formation of petroleum to the action of water at high See also:tempera-, tures on See also:iron See also:carbide in the interior of the See also:earth . On the other hand, an overwhelming and increasing majority of those who have studied the natural conditions under which petroleum occurs are of opinion that it is of organic origin . The earlier sup-porters of the organic theory held that it was a product of the natural distillation of See also:coal or carbonaceous matter; but though in a few instances volcanic intrusions appear to have converted coal or allied substances into oil, it seems that terrestrial vegetation does not generally give rise to petroleum . Among those who have considered that it is derived from the decomposition of both See also:animal and See also:vegetable marine organisms may be mentioned J . P . See also:Lesley, E . See also:Orton and S . F . See also:Peckham, but others have held that it is of exclusively animal origin, a view supported by such occurrences as those in the orthoceratities of the Trenton limestone, and by the experiments of C .
Engler, who obtained a liquid like crude petroleum by the distillation of See also:menhaden (See also:fish) oil
.
Similarly there is a difference of opinion as to the conditions under which the organisms have been mineralized, some holding that the process has taken See also:place at a high temperature and under great pressure; but the lack of See also:practical See also:evidence in nature in support of these views has led many to conclude that petroleum, like coal, has been formed at moderate temperatures, and under pressures varying with the depth of the containing rocks
.
This view is supported by the fact that petroleum is found on the Sardinian and See also:Swedish coasts as a product of the decomposition of seaweed, heated only by the See also:sun, and under atmospheric pressure
.
See also:Consideration of the evidence leads us to the conclusion that, at least in commercially valuable deposits, mineral oil has generally been formed by the decomposition of marine organisms, in some cases animal, in others vegetable, in others both, under practically normal conditions of temperature and pressure
.
Extraction (Technically termed Production.)—The earliest See also:system adopted for the collection of petroleum appears to have consisted in Early skimming the oil from the surface of the water upon Methods. which it had accumulated, and Professor Lesley states
that at Paint Creek, in See also: The " See also:wild-See also:cat " wells, sunk by speculators on untested territory or on lands which had not previously proved productive, played an important part in the earlier mapping out of the petroleum fields . To discourage the sinking of wells on land immediately adjoining productive territory, it has been usual to drill along the See also:borders of the land as far as practicable, in order to first obtain the oil which might otherwise be raised by others; and on account of the small See also:area often con-trolled by the operator, the number of wells drilled has frequently been far in excess of the number which might reasonably be sunk . Experience has proved that in some of the oil fields of the United States one well to five acres is as See also:close as they should be drilled . After the selection of the site, the first operation consists in the erection of the rig . The chief portion of this rig is the See also:derrick, OII which consists of four strong uprights or legs held in Derrick position by ties and braces, and resting on strong wooden sills, which are preferred, as a See also:foundation, to See also:masonry . For drilling the deeper wells, the derrick, on account of the length of the " See also:string " of drilling tools, is usually at least 70 ft. high, about 20 ft. wide at the base, and 4 ft. wide at the See also:summit . The whole derrick is set up by keys, no mortices or tenons being used, and thus the complete rig may be readily taken down and set up on a new site . The See also:samson-See also:post, which supports the walking See also:beam, and the See also:jack-posts, are See also:dove-tailed and keyed into the sills . The samson-post is placed flush with one See also:side of the main See also:sill, the See also:band-See also:wheel jack-post being flush with the other side, so that the walking-beam, which imparts See also:motion to the string of tools, See also:works parallel with the main sill . The See also:boiler generally used is of the See also:locomotive type and is usually stationary, though sometimes a portable form is preferred . It is either set in the first instance at some distance from the See also:engine and well, or is subsequently removed sufficiently far away before the drill enters the oil-bearing formation, and until the oil and gas are under See also:control, in order to minimize the See also:risk of See also:fire . A large boiler frequently supplies the engines of several wells . The engine, which is provided with See also:reversing See also:gear, is of 12 or 15 See also:horse-power and motion is communicated through a See also:belt to the band-wheel, which operates the walking-beam by means of a See also:crank . The throttle-See also:valve is opened or closed by turning a grooved See also:vertical See also:pulley by means of an endless See also:cord, called the See also:telegraph, passing See also:round another pulley fixed upon the " headache-post," and is thus under the control of the driller working in the derrick . The headache-post is a vertical wooden beam placed on the main sill directly below the walking-beam, to receive the weight of the latter in case of breakage of connexions . The position of the reversing See also:link is altered by means of a cord, passing over two pulleys, fixed respectively in the engine-See also:house and on the derrick . At one end of the hand-wheel See also:shaft is the See also:bull-rope pulley, and upon the other end is a crank having six holes to receive a movable See also:wrist-See also:pin, the length of stroke of the walking-beam being thus adjusted . The revolution of the bull-wheels is checked by the use of a powerful, hand-See also:brake . The band-wheel communicates motion to the walking-beam, while drilling is in progress, through the crank and a connecting-See also:rod known as the See also:pitman; to the bull-wheels, while the tools are being raised, by the bull-rope; and to the See also:sand-See also:pump See also:reel, by a See also:friction pulley, while the sand-pump is being used . It is therefore necessary that the machinery should be so arranged that the connexions may he rapidly made and broken . The sand-pump reel is set in motion by pressing a See also:lever, the reel being then brought into contact with the See also:face of the hand-wheel . The sand-pump descends by See also:gravitation, and its fall is checked by pressing hark the lever, so as to throw the reel against a post which serves as a brake . The drilling tools are suspended by an untarred See also:manila rope, 2 in. in See also:diameter, passing from the bull-wheel shaft over a grooved wheel known as the See also:crown-pulley, at the summit of the derrick . The string of drilling tools consists of two Drilling parts separated by an appliance known as the jars . 
Tools
.
This piece of apparatus was introduced by See also: On the down-stroke, the auger-stem falls 20 in., while the sinker-bar goes down 24 in. to See also:telescope the jars for the next blow coming up . A skilful driller never allows his jars to strike on the down-stroke, they are only used to jar down when the tools stick on some obstruction in the well before reaching the bottom, and in fishing operations . An unskilful workman sometimes ' loses the jar ' and works for See also:hours without accomplishing anything . The tools may be See also:standing at the bottom while he is playing with the slack of the cable or they may be swinging all the time several feet from the bottom . As the jar works off, or grows more feeble, by See also:reason of the downward advance of the drill, it is ' tempered ' to the proper strength by letting down the temper-screw to give the jars more play . The temper-screw forms the connecting link between the walking-beam and cable, and it is ' let out ' gradually to regulate the play of the jars as fast as the drill penetrates . When its whole length is run down, the rope clamps play very near the well-mouth . The tools are then withdrawn, the well is sand-pumped, and preparations are made for the next ' run.' " The See also:ordinary sand-pump or bailer, consists of a See also:plain See also:cylinder of light galvanized iron with a See also:bail at the See also:top and a stem-valve at the bottom . It is usually about 6 ft. in length but is sometimes as much as 15 or 20 ft., and as its valve-stem projects downwards beyond the bottom, it empties itself when rested upon the bottom of the See also:waste-trough . The operation of drilling is frequently interrupted by the occurrence of an See also:accident, which necessitates the use of fishing tools . If the fishing operation is unsuccessful the well has to be abandoned, often after months of labour, unless it is found possible to drill past the tools which have been lost . In readiness for a fracture of the drilling tools or of the cable, See also:special appliances known as fishing tools are provided . These are so numerous and varied in form that a description would be impossible within the See also:scope of this article . The fishing tools are generally attached to the cable, and are used with portions of the ordinary string of tools, but some arc fitted to pump-rods or tubing, and others to special rods . The drilling of a well is commonly carried out under See also:contract, the producer erecting the derrick and providing the engine and boiler while the drilling contractor finds the tools, and is Drilling the responsible for accidents or failure to complete the Will well . The drilling " See also:crew " consists of two drillers and two See also:tool-dressers, working in pairs in two " See also:tours " (See also:noon to midnight and midnight to noon) . The earlier wells in Pennsylvania consisted of three sections, the first formed of surface See also:clays and gravels, the second of stratified rocks containing water, and the third of stratified rocks, including the oil-sands, usually See also:free from water . The conductor, which was a wooden casing of somewhat greater See also:internal diameter than the maximum bore of the well, passed through the first of these divisions, and casing was used in the second to prevent percolation of water into the oil-bearing portion . In later wells the conductor has been replaced with an 8-in. wrought-iron drive-See also:pipe, terminating in a See also:steel See also:shoe, which is driven to the See also:bed-rock, and a 7$-in. hole is drilled below it to the base of the lowest water-bearing stratum . The bore is then reduced to 5f-in., and a bevelled See also:shoulder being made in the rock, a 5f-in. cjtsing, having a See also:collar to See also:fit water-tight on the See also:bevel shoulder, is inserted . The well is then completed with a S%- in. See also:hit . As the water is shut off before the portion of the well below the water-bearing strata is bored the See also:remainder of the drilling is conducted with only sufficient water in the well to admit of sand-pumping . The drill is thus allowed to fall freely, instead of being partly upheld by the buoyancy of the water, as in earlier wells . Wells in Pennsylvania now range in depth from 300 ft. to 3700 ft .
Four strings of iron casing are usually employed, having the following diameters: 10 in., 8; in., 61 in. and 5 in., the lengths of See also:tube forming the casing being screwed together
.
Contractors will often undertake to drill wells of moderate depth at 90 cents to $t per See also:foot, but the cost of a deep well may amount to as much as $7000
.
The rotary system of drilling which is in general use in the oil-fields of the coastal plain of Texas is a modification of that invented
Rotary by Fauvelle in 1845, and used in the early years of the
system. industry in some of the oil-producing countries of
Europe
.
It is one of the most rapid and economical which can be employed in soft formations, but where hard rock is encountered it is almost useless
.
The principle of this system consists essentially in the use of rotating hollow drilling rods or casing, to which is attached the drilling-bit and through which a continuous stream of water, under a pressure of 40 to 100 lb. per sq. in., is forced
.
The yield of petroleum wells varies within very wide limits, and the relative importance of the different producing districts is also
Yield of constantly changing
.
I
.
C
.
See also: A flow of oil may often be induced in a well which would otherwise require to be pumped, by preventing the See also:escape of gas which issues with the oil, and causing its pressure to raise the oil . The See also:device employed for this purpose is known as the water-See also:packer, and consists in its simplest form of an See also:india-See also:rubber See also:ring, which is applied between the tubing and the well-casing, so that upon compression it makes a tight See also:joint . The gas thus confined in the oil-chamber forces the oil up the tubing . For pumping a well a valved working-See also:barrel with valved sucker is attached to the lower end of the tubing, a perforated "See also:anchor " being placed below . The sucker carries a series of three or four See also:leather cups, which are pressed against the inner surface of the working barrel by the weight of the See also:column of oil . The sucker is connected by a string of sucker-rods with the walking-beam . There is usually fixed above the sucker a See also:short iron valve-rod, with a device known as a See also:rivet-catcher to prevent damage to the pump by the dropping of rivets from the pump-rods . On the completion of drilling, or when the production is found to decrease, it is usual to See also:torpedo the well to increase the flow . Torpedoing The explosive employed is generally See also:nitroglycerin, Wells. and the amount used has been increased from the original 4 to 6 quarts to 6o, 80, too and even 200 quarts . It is placed in See also:tin canisters of about 31 to 5 in. in diameter and about to ft. in length . The canisters have conical bottoms and fit one in the other . They are consecutively filled with nitro-See also:glycerin, and are lowered to the bottom of the well, one after the other, by a cord See also:wound upon a reel, until the required number have been inserted . Formerly the upper end of the highest canister was fitted with a " firing-See also:head," consisting of a circular See also:plate of iron, slightly smaller than the bore of the well, and having attached to its underside a vertical rod or pin carrying a percussion cap . The cap rested on the bottom of a small iron cylinder containing nitroglycerin . To explode the See also:charge an iron weight, known as a go-See also:devil, was dropped into the well, and striking the disk exploded the cap and fired the torpedo . Now, however, a See also:miniature torpedo known as a go-devil See also:squib, holding about a quart of nitro-glycerin, and having a firing-head similar to that already described, is almost invariably employed . The disk is dispensed with, and the percussion cap is exploded by the impact of a leaden weight See also:running on a cord . The squib is lowered after the torpedo, and, when exploded by the descent of the weight, fires the charge . It must be See also:borne in mind that although the See also:explosion may increase the production for a time, it is by no means certain that the actual output of a well is increased in all such cases, though from some wells there would be no production without the use of the torpedo . The petroleum industry in Canada is mainly concentrated in the district of See also:Petrolea, Ontario . On account of the small Drillingln depth of the wells, and the tenacious nature of the Canada. principal strata bored through, the See also:Canadian method of drilling differs from the Pennsylvanian or American system in the following particulars: 1 . The use of slender wooden See also:boring-rods instead of a cable . 2 . The employment of a simple auger instead of a spudding-bit . 3 . The adoption of a diffeient arrangement for transmitting motion . 4 . The use of a lighter set of drilling tools . Although petroleum wells in Russia have not the depth of manyof those in the United States, the disturbed character of the strata, with consequent liability to caving, and the occurrence of hard concretions, render drilling a lengthy and expensive Drilling in operation . It is usual to begin by making an excava- Russia . tion 8 ft. in diameter and 24 ft. in depth, and lining the sides of this with See also:wood or See also:brick . The initial diameter of the well drilled from the bottom of this See also:pit is in some instances as much as 36 in., bore-holes of the larger See also:size being preferred, as they are less liable to become choked, and admit of the use of larger bailers for raising the oil . The drilling of wells of large size requires the use of heavy tools and of very strong appliances generally . The system usually adopted is a modification of the Canadian system already described, the boring rods being, however, of iron instead of wood, but the cable system has also to some extent been used . For the ordinary 2-in. plain-laid manila cable a See also:wire rope has in some cases been successfully substituted . Rivetted iron casing, made of 136 -in. plate, is employed, and is constantly lowered so as to follow the drill closely, in order to prevent caving . Within recent years, owing to the initiative of See also:Colonel See also:English, a method of raising oil by the agency of compressed air has been introduced into the Baku oil-fields . In Galicia the Canadian system is nearly exclusively adopted . In some instances under-reaming is found necessary . This consists in the use of an expanding reamer by means of which Drilling is the well may be drilled to a diameter admitting of the Galicia . casing descending freely, which obviously could not be accomplished with an ordinary bit introduced through the casing . Of See also:late years the under-reamer has been largely superseded by the See also:eccentric bit . The See also:Davis calyx drill has also been employed for petroleum drilling . This apparatus may be described as a steel-pointed core-drill . The bit or cutter consists of a cylindrical The calyx metallic See also:shell, the lower end of which is made, by a Drill . process of gulleting, into a series of sharp See also:teeth, which are set in and out alternately . The outward set of teeth drill the hole large enough to permit the drilling apparatus to descend freely, and the teeth set inwardly See also:pare down the core to such a diameter as will admit of the See also:body of the cutter passing over it without seizing . The calyx is a long tube, or a series of connected tubes, situated above the core barrel, to which it is equal in diameter . In conclusion it may be stated that the two systems of drilling for petroleum with which by far the largest amount of work has been, and is being done, are the American or rope comparison system, and the Canadian or rod system . The former of systems. is not only employed in the United States, but is in use in Upper Burma, Java, Rumania and elsewhere . The latter was introduced by Canadians into Galicia and, with certain modifications, has hitherto been found to be the best for that country . A form of the rod system is used in the Russian oil-fields, but owing to the large diameter of the wells the appliances differ from those employed elsewhere . The wells from which the supplies of natural gas are obtained in the United States are drilled and cased in the same manner as the oil wells . Transport and Storage.—In the early days of the petroleum industry the oil was transported in the most See also:primitive manner . Thus, in Upper Burma, it was conveyed in earthenware vessels from the wells to the See also:river See also:bank, where it was poured into the holds of boats . It is interesting to find that a See also:rude pipe-See also:line formerly existed in this field for conveying the crude oil from the wells to the river; this was made of bamboos, but it is said that the loss by leakage was so great as to See also:lead to its immediate See also:abandonment on completion . In Russia, until 1875, the crude oil was carried in barrels on See also:Persian carts known as " arbas." These have two wheels of 81 to 9 ft. in diameter, the body carrying one barrel, while another is slung beneath the See also:axle . In America, crude petroleum was at first transported in iron-hooped barrels, holding from 40 to 42 American gallons, which were carried by teamsters to Oil Creek and the See also:Allegheny River, where they were loaded on boats, these being floated down stream whenever sufficient water was present—a method leading to much loss by collision and grounding . Bulk See also:barges were soon introduced on the larger See also:rivers, but the use of these was partially rendered unnecessary by the introduction of See also:railways, when the oil was at first transported in barrels on See also:freight cars, but later in tank-cars . These at first consisted of an ordinary See also:truck on which were placed two wooden tub-like tanks, each holding about 2000 gallons; they were replaced in 1871 by the modern type of tank-See also:car, constructed with a horizontal cylindrical tank of boiler plate .
The means of transporting petroleum in bulk commonly used at the present day is the pipe-line system, the history of which See also:dates from 186o
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In that year S
.
D
.
Karns suggested laying a 6-in. pipe from Burning Springs to See also:Parkersburg, West Virginia, a distance of 36 m.; but his proposal was never carried into effect
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Two years later, however, L
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See also:Hutchinson of New York, laid a short line from the Tarr See also:Farm wells to the refinery, which passed over a See also: The barrels employed in the transport of petroleum See also:pro-ducts are made of well-seasoned white-See also:oak staves See also:bound by six or eight iron hoops . They See also:ate coated internally with See also:glue, and painted in the well-known See also:colours, See also:blue staves and white heads . The tins largely used for kerosene are made by machinery and contain 5 American gallons . They are hermetically sealed for transport . In Canada, means of transport similar to those already described are employed, but the reservoirs for storage often consist of excavations in the soft See also:Erie See also:clay of the oil district, the sides of which are supported by planks . The primitive methods originally in use in the Russian oil-fields have already been described; but these were long ago superseded by pipe-lines, while a great See also:deal of oil is carried by tank steamers on the See also:Caspian to the mouth of the See also:Volga where it is transferred to barges and thence at Tzaritzin to railway tank-cars . The American type of storage-tank is generally employed, in See also:conjunction with clay-lined reservoirs . Natural gas is largely used in the United States, and for some time, owing to defective methods of storage, delivery and See also:consumption, great waste occurred . The improvements introduced in 1890 and 1891. whereby this state of affairs was put an end to, consisted in the introduction of the principle of supply by See also:meter, and the adoption of a comprehensive system of reducing the initial Pressure of the gas, so as to diminish loss by leakage . For the latter purpose, Westinghouse gas-regulators are employed, the positions of the regulators being so chosen as to equalize the pressure throughout the service . The gas is distributed to the consumer from the wells in wrought-iron pipes, ranging in diameter from 20 in. down to 2 in . Riveted wrought-iron pipes 3 ft. in diameter are also used . The initial pressure is sometimes as high as 400 lb to the sq. in., but usually ranges from 200 to 300 lb . The most common method of See also:distribution in cities and towns is by a series of pipes from 12 in. down to 2 in. in diameter, usually carrying a pressure of about 4 oz. to the sq. in . To these pipes the service-pipes leading into the houses of the consumers are connected . Refining of Petroleum.—The distillation of petroleum, especially of such as was intended for medicinal use, was regularly carried on in the 18th century, and earlier . V . I . Ragozin states in his work on the petroleum industry that Johann Lerche, who visited the Caspian district in 1735, found that the crude Caucasian oil required to be distilled to render it satisfactorily combustible, and that, when distilled, it yielded a See also:bright yellow oil resembling a spirit, which readily ignited . As early as 1823 the See also:brothers Dubinin erected a refinery in the See also:village of Mosdok, and in 1846 applied to See also:Prince Woronzoff for a See also:subsidy for extending the use of petroleum-distillates in the Caucasus . In their application, which was unsuccessful, they stated that they had taught the See also:Don See also:Cossacks to " change black naphtha into white," and showed by a See also:drawing, preserved in the archives of the Caucasian See also:government, how this was achieved . They used an iron still, set in See also:brickwork, and from a working charge of See also:forty " buckets " of crude petroleum obtained a yield of sixteen buckets of "" white naphtha." The top of the still had a removable head, connected with a See also:condenser consisting of a See also:copper See also:worm in a barrel of water . The " white naphtha ' was sold at Nijni See also:Novgorod without further treatment . Some of the more viscous crude oils obtained in the United States are employed as See also:lubricants under the name of " natural oils," either without any treatment or after clarification by subsidence and filtration through animal See also:charcoal . Others are deprived of a part of their more volatile constituents by spontaneous evaporation, or by distillation, in vacuo or otherwise, at the lowest possible temperature . Such are known as " reduced oils." In most petroleum-producing countries, however, and particularly where the product is abundant, the crude oil is fractionally distilled, so as to separate.it into petroleum spirit of various grades, burning oils, gas oils, lubricating oils, and (if the crude oil yields that product) paraffin . The distillates obtained are usually purified by treatment, successively, with sulphuric acid and See also:solution of See also:caustic soda, followed by washing with water . |
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