USRE5284E - Improvement in the manufacture of inflammable gases for fuel - Google Patents

Description

UNITED STATES PATENT O FIGE WILLIAM ELMER, on NEW YORK, N. Y.

IMPROVEMENT IN THE MANUFACTURE OF I NFLAMMABLE GASES FOR F UEL, 8m.

Specification forming part of Letters Patent No. 106,669, dated August 23, 1870; antedated August 1'2, 1870;

- reissue No. 5,284, dated February 18, 1873.

' To all whom it may concern:

Be it known that I, WILLIAM ELMER, of the city, county, and State of New York, have invented a new and useful method or process of eliminating in an isolated and gaseous condition the heat-producing elements contained in ordinary fuel and in other substances. These isolated and gaseous elements are intended to be used for heating purposes instead of ordinary fuel, and for other uses to which they may be applicable; and I do hereby declare that thefollowing is a full, clear, and exact description of my said invention.

In my specification contained in certain Letters Patent granted to me bythe United States, and dated the 13th day of February, 1869, I there represented the process of gasifying fuel by employing retorts set in. ahorizontal position, and whichretorts'were divided through the center by means of a partition. This at rangement of retorts answered very well the purpose for which it was intended, but not as perfectly as the arrangement and process hereinafter described.

In order to give a clear understanding of the nature and object of my present invention, I deem it necessary to make some more particular statements as to the effect of heat upon the products given ofi from ordinary fuel when subjected to the process of distillation, and the reactions and other effects produced by the application of high heat to the products of the destructive distillation of such ordinary fuel in order that the nature and extent of my improvement may be fully comprehended.

The materials usually employed in the production of artificial heat are coal, wood, and peat, which, though very dissimilar in appearance, are composed mainly of the same elements-namely, carbon, hydrogen, oxygen, and small but variable proportions of nitrogen, sulphur, and other elements, which constitute the ash when fuel is burned; but of all these elements two only in their union with oxygen by combustion can take any part in the production of heat; these are carbon and hydrogen. The other elements in fuel are very objectionable, because, being in combination with the heat-producing elements, they reduce the available quantity of these substances, and'in combustion they enter into new combinations, which again reduce the heat-producin g elevolume of gases is produced,

ments, while the compounds thus formed be come the vehicle for the transmission of a large share of the heat from the point of ignition to the surrounding atmosphere, so that the actual calorific effects of the combustion of ordinary fuel are by this means reduced to a mere nominal power; besides, most of the heat thus generated as ordinarily usedis carried off by the flues and lost for practical purposes, so that the actual quantity of heat utilized from ordinary fuel is only about ten per cent. of the whole amount that the heat-producing agents are capable of yielding. To obviate these objections so far as to utilize the heat-producin g elements contained in fuel, I propose to eliminate these in the form of gases. To accomplish this object, I subject the fuel intended to be used as gas-stock to a series of distilla' tions out of contact with the atmosphere, and decompose and convert such of the distillates as contain the heat-producing elements that are condensable and non-inflammable into inflammable gases.

It is well known that when bituminous and cannel coal are subjected to the process of distillation at a low red heat (700 to 800 Fahrenheit) they yield a variety of compounds, among which are aqueous vapors, free hydro gen, carbureted hydrogen, carbonic acid, light v'olatile hydrocarbons condensable into spirit or oil; and as the distillation goes on other condensable oils of different specific gravities are given off, and among which are heavy oils and what is called dead-oil, which mixme chanically with other products and settle to the bottom of the receiving-vessel, and the compound thus formed is called tar. The nitrogen and sulphur present enter into new combinations, producing ammoniacal and sulphur compounds. In the retort there finally remains a quantity of fixed carbon or coke containing the ash, which usually consists of silica, alumina, lime, and the oxides of manganese, iron, and some other substances. The condensable distillates, which constitute the principal product of the coal, subside in the receiver into different stratums, according to their specific gravities.

If the coal be subjected to higher tempera tures than those referred to, the products of distillation are somewhat changed, a larger and less .con-

densable matter, and, consequently, more carbon remains in the retort. j

When bituminous andcannel coals are subjected to the process of distillation under a full white heat the products are chiefly hydrogen, light carbureted hydrogen, and carbonic oxide. Bisulphide of carbon, sulphureted hydrogen, ammonia, cyanogen N 0 0 Y, and sulphocyanogen O N S 0 Y S; are also formed. The amount of carbonaceous matter left in the retort under a white heat is much larger than under a red heat. Under the latter temperature from forty to forty-five per cent. of the carbon contained'in the coal remains in the retort, while under a white heat from sixty- --five to seventy per cent-remains.

It is evident, from the products obtained from the distillation of coal under various temperatures, that neither a high nor low heat alone is suited to the process of eliminating and gasifying the heat-producing elements contained in coal. Under the former the products given oil from the coal are mostly gaseous and solid; under the latter, fluid and solid. The gases produced'under a high heat alone, though much larger in amount than under a low heat'alone, seldom amount to more than ten thousand cubic feet to the ton of coal. Be-

, sides, the compounds produced other than gaseous hydrocarbons under .both a high and low heat are not only numerous but are wholly unfitted for. the production of heat.

An example of what occurs in the distillation of bituminous coal under diiferent temperatures isafforded in the manufacture of illuminating-gas. The process of the distillation of coal, as ordinarily practiced in the manufacture of illuminating-gas, is attended with the production of a great variety of compounds other than'illuminating-gas, and hence the results, both to the manufacturer and the consumer, are unsatisfactory. With a low heat the quantity of gas produced is small,

though'its luminosity is good. With a high heat a larger quantity is produced, yet its luminosity is very poor, while a medium temperature is attended with neither economy nor the production of a gas of a satisfactory quality." Hence, in either case, the result is a cost- 1 y product to consumers.

Wood and" peat subjected to the process of distillation 'un der various temperatures yield similar products to those obtained from bituminous coal.

In the distillation of wood the following are obtained: Light carbureted hydrogen, hydrogen, hydrocarbons of the olefiant-gas series, carbonic oxide, carbonic acid, pyroligue'ous or impure acetic acid, eupione, pyroxanthine, paraflin'e, creosote, oxyphenic acid, pittacal, ammonia, aqueous vapor, volatile and fixed oils, wood-tar; and charcoal, which contains the ashes or inorganic constituents, is left in theretort. a

f P amt... wept-satiation o Peat.

bonic acid, carbonic oxide, hydrocarbons of" the olefiant-gas series, volatile and fixed oils, paraffine, creosote, acetic acid, 'animonia,sulphate of ammonia, pyroxylic spirit or wood naphtha, aqueous vapor, peat-tar and charcoal remains in the retort.

Analysis of crude fuel.

The analysis of the chief products given oil from different kinds of crude fuel by distillationunder various temperatures shows that they are constituted as follows:

First, gaseous productshydrogen and by drocarbons: Hydrogen, H; light carbureted hydrogen, 0 H olefiant gas or ethylene, G Hgacetylene, (3.; H propylene, 0 H bu tylene or tetrylene, (3 H Second, liquid products-light oily hydrocarbons: Benzole, G H toluol, 0 H cu mol, (3 E cymol, U H photogen, light paraffine oil, and other hydrocarbon oil of the paraffine series.

Third, solid hydrocarbon products: Par-al fine, (J H naphthaline, O H paranap'hthaline, O H pyrene, G H crysene, (3

Fourth, intro-hydrocarbon, mobile oily products: Aniline, O H N; chinoline, 0 H N; leucolene, G H N; picoline, 0 H-, N; pyridine, 0 H N; toluidine, 0 B9 N.

Fifth, ammoniacal compounds: Carbonate of ammonia, N H, O O 0 sulphate of ammonia,

N H. O S 0 hydrosulphate of sulphide of ammonium, N H S H S.

Sixth, sulphureted-hydrogen gas, H S.

Seventh, bisulphide of carbon, (liquid,) 0 S Eighth, gaseous oxides of carbon: Carbonic oxide, (1 O; carbonic anhydride, 0 O

Ninth, carbolic acid-phenol, O H

Tenth, aqueous products-water, H 0.

First scries.-The gaseous hydrocarbons, when passed through tubes heated to a full redness, are decomposed, and deposit all but one equivalent of their carbon, and light carbureted hydrogen is formed. 1f the latter compound be passed through tubes heated to an intense whiteness, it is also decomposed, its carbon is deposited, and a volume of hydrogen double that of the original gas is liberated.

Second serie s.The light oily hydrocarbons, when distilled at a red heat, deposit a portion of their carbon, and are converted. into posed, depositing all but one equivalent of their carbon, and double their volume oflight carbureted hydrogen is formed.

Thirdseries-The solid hydrocarbons, for the most part, may be distilled when subject- 'ed'to avery high heat, but without much change in their composition. hen'distilled at a white heat in contact with highly-heated steam they are decomposed, and a rearrangement of their elements occurs; a large pro- .portion of their carbon is deposited, and hydrocarbon gases are formed of the ethylene series 0 H the'oxygen of the steam combines with a portion of the carbon, to form carbonic oxide while the hydrogen of the steam is set free. The hydrocarbon gases of this series, like oletia-nt gas, are decomposed when passed through highly-heated tubes, forming light carbureted hydrogen and depositing carbon.

Fourth series-When the vapor of nitrohydrocarbons is passed through highly-heated tubes carbon is'deposited, ammonia and a small quantity of hydrocyanic acid are given off, and a dense hydrocarbon liquid remains in the receiver. If this liquid be subjected to a white heat in contact with highly-heated steam, similar results occur to that described in the decomposition of the compounds of the third series.

Fifth series.-Oarbonate of ammonia is volatilized by heat, and, when passed through a heated tube with steam, it is decomposed, a portion of the ammonia and carbonic acid is evolved, and a solution of a single carbonate remains. When sulphate of ammonia is subjected to a temperature of only 536 Fahrenheit it is decomposed, nitrogen and ammonia are liberated, and sulphite of ammonia and water are formed. Hydrosulphate of sulphide of ammonia is decomposed when, passed through highly-heated tubes, a small quantity of sulphur is deposited, and ammonia and sulphureted hydrogen are liberated.

Sixth series.-Sulphureted hydrogen is decomposed when the gas is passed through a tube heated to full redness, the sulphur is deposited in the receiver, and the hydrogen is set free.

Seventh series-The vapor of bisulphide of carbon is decomposed when passed through tubes heated to whiteness with intensely-heated-steam. The oxygen of the steam unites with the carbon to form carbonic oxide, and thehydrogen with the sulphur to form sulphureted hydrogen, whichv is decomposed by heat, as above stated.

Eighth series-Carbonic oxide remains unchanged when passed through tubes heated to the highest intensity. Carbonic anhydride, (acid,) when passed through tubes filled with carbon highly heated, is decomposed and converted into carbonic oxide.

Ninth series-Garbolic acid. is decomposed only to a limited extent when passed through ared-hot tube, yielding a small quantity of solid olefiant gas, (naphthaline,) but when passed, with highly-heated steam, through a tube heated to whiteness it yields a variety of compounds, among which are oxides of carb011, free carbon, and hydrocarbon gas, identicalwith olefiant gas. This gas burns with a white smokeless flame, of peculiar splendor .and brilliancy.

Tenth series-Aqueous vapor, as is well known, is decomposed when passed through a tube filled with small shavings or strips of iron heated to a bright redness; also when highly-heated steam is brought in contact with the vapor of metallic zinc; likewise when highly-heated steam is brought in contact with incandescent carbon. cases the oxygen of the steamcombines with the metals, forming solid oxides, while the hydrocarbon is liberated. With the latter the oxygen unites with the carbon to form the gaseous oxides of carbon, while the hydrogen is set free.

Eleventh series-Substances obtained from the distillation of wood and peat: Acetic acid 0 H 0 H. When vapor of acetic acid is passed through a red-hot tube a portion is decomposed, yielding free carbon and combustible gases, acetone, naphthaline, hydrate of phenol, and benzole. If the vapor of acetic acid be passed through carbon in a highlyheated tube it is entirely'decomposed, yielding hydrocarbon gases and carbonic oxide. Acetone, 0 H 0 when passed in a state of vapor through a red-hot tube, deposits carbon, and is converted into a peculiar oil called dumasin. This oil, when passed'over incandescent carbon, is converted into inflammable gases. Eupione, O H The vapor of eupione is decomposed when passed through a highly-heated tube, yielding hydrocarbon gases. Methylic alcohol, 0 H 0 syn., wood naphtha, pyroxylic spirit. The vapor of methylic alcohol, passed through a red-hot tube, yields olefiant gas and aqueous vapor. Pyroxanthine, 0 H 0 when highly heated, is decomposed, depositing carbon and yielding inflammable gases and aqueous vapor. Oreosote, (J H 0 The vapor of creosote, when passed through a tube heated to whiteness, is decomposed, depositing carbon and yielding inflammable gases and aqueous vapor. H 0 is decomposed when its vapor is passed through carbon in a tube heated to whiteness.

zC-arbonic acid and propylene are produced.

There are a few other compounds resulting from the distillation of crude fuel, but not of sufiicient importance to our present objectto require notice.

From the foregoing statement it is evident that the products, excepting the permanent gases, resulting from the distillation of the various kinds of crude fuel may be decomposed, and the heat-producin g elements they contain isolated and converted into permanent inflammable gases. But the heat -producing elements contained in crude fuel maybe more conveniently and efi'ectually eliminated in the gaseous condition by subjecting the distillate to the high heat named herein while in the form of vapor and before it has lost the heat it has acquired, so as to avoid the formation of the compounds named by condensation. At a lower heat some of the products escape decomposition, and, upon cooling, condense and appear in the form of tar, ammonia, &c.,

In the former Oxyphenic acid, 0

the retorts is made in the usual form. A the retorts is set in the bench in a horizontal position, as is usual in gas-works. The other containing, as an element, hydrogen, which a higher heat would have liberated.

- named, with greater certainty, convenience,

and effect than have hitherto been attained.

' The method pursued and the apparatus employed are as follows! The bench for holding One of two retorts are set in a vertical position, one on either side of the horizontal retort. The latter retort I have, for convenience, denominated the receiving-retort, as the fuel to be subjected to the process is placed in this retort, which is made larger than the vertical retorts. The vertical retorts are made in the form of a boot-that is, the lower end of these retorts, when placed in position, turn outward and protrude through the wall of the bench in order to admit the attachment of mouth-pieces to the retorts, so that when the mouth-piece is also attached to the receivin gretort the bench presents the appearance of an ordinary bench of three retorts. The receiving -cretort is connected with one of the vertical retorts by means of a pipe inserted into the mouth-piece of both. The two verticalretorts are connected with each other at the top of the bench by means of a pipe. To the mouth-piece of the vertical-retort not connected with the receiving-retort is attached the stand-pipe to convey the gas from the retorts to the hydraulic main. The two vertical retorts are filled with small pieces of fire-brick or other suitable substance indestructible by heat. These retorts must be kept at a white heat of not less than 2000 Fahrenheit, and, preferably, from 2,500 to 3,000 The crude i'uel or material subjected to the process of volatilization is first. placed in the receivingretort, where it is subjected to the process of distillation under a red heat of from 800 to 1000 Fahrenheit, according to the nature of the material employed. The volatile products, as eliminated from this material, are

, conveyed directly into the vertical retort con nected with the receivingretort and pass up through the white-hot material contained inthis retort. The object of the material in the vertical retorts is to divide the volatile products into infinitesimal particles or streams, and to retain in the retorts the free carbon and solid hydrocarbons by filtration, so that none of these substances go over with the gases from the retorts.

It is obvious that from the position of the material in the vertical retort no gas or vapor can traverse the retort without passing through and being'brought in contact with the whitehot surfaces of the particles of the mass, whereas in a horizontal retort coke, coal, brokenhricks, or any other comminuted material, however compactlythe retort may be filled with it, is liable to settle down and leavea vacant space at the top, through which gas and vapors may pass without contact. By this means the volatile hydrocarbons given off by distillation from the materials employed are decomposed, depositing free carbon and solid hydrocarbons of the third series and forming a variety of gases of different specific gravities. These gases, with more or less vapors, which have escaped decomposition in the first vertical retort, pass from this retort through the con necting-pipe into and down through the other vertical retort when a second vertical retort is used, where, in their passage through the in: candescent material'contained in this retort, they again deposit a portion of their carbon and are converted into permanent inflammable gases. The aqueousvapor formed in the receiving-retort is also decomposed in the first vertical retort, where it comes in contact with carbon deposited there, and which, under the high heat, has become incandescent. Both carbonic oxide and carbonic acid are formed in the decomposition of the aqueous vapor by carbon, and the hydrogen of the steam is set free, while the carbonic acid is decomposed in its passage through the incandescent carbon deposited in the second vertical retort, and is changed into carbonic oxide. When the material subjected to distillation in the receiving-retort ceases to give off gaseous and volatile products, then steam heated to redness may be admitted in small and regulated quantities into this retort, where a portion of it is decomposed, forming the oxides of carbon and liberating hydrogen, but the greater portion of the steam passes on in contact with the free carbon and solid hydrocarbons, remaining in the vertical retorts, where a rearrangement of the elements of steam and the solid hydrocarbons and free carbons takes place, and which results in the formation of permanent inflammable gases of different specific gravities.

The hydrocarbons of the third series are principally formed in the receiving-retort and volatilized by heat, and hence are displaced by distillation with the other volatile products and carried into the vertical retorts, where they are partially decomposed, giving up a portion of the hydrogen they contain and be come solid, and are deposited in these retorts where they are no longer volatilized by heat, but may be transformed into inflammable gases by highly-heated steam, as 'above stated. It is these compounds that are so annoying and troublesome to the manufacturers of illuminating-gas. They are given off from coal by distillation with other products and become deposited in the stand-pipes, often filling them up solid. These deposits have to be removed with bars of iron and are a dead waste in the ordinary manufacture of illuminating-gas, and yet they are composed of carbon and hydrogen-the very materials essential to the prodnction of gas, but cannot be utilized in the ordinary process of gas-making,

By my invention these compounds are destructive to the retorts wholly utilized, as well as the product known as coal-tar, by conversion into permanent inflammable gases.

New Process of Gas Manufeature.

Advantages of the cubic feet.

Second. The receiving-retort is designed to hold a ton or more of coal at avsingle charge, which is placed in the retort by machinery so quickly that little or no loss of gas occurs. At the same time a great'saving of labor and time is effected.

Third. The receiving-retorts require chargin g only three times in twenty-four hours; whereas, in the manufacture of illuminatinggas, as ordinarily conducted, the retorts are charged about every four hours, which is very from the frequent introduction of cold material into them while highly heated.

Fourth. By the new process all the coal-tar and other heavy hydrocarbons, and free carbons not utilized in the ordinary manufacture of illuminatinggas, are converted into permauent inflammable gases.

Fifth. The gas manufactured bylthe new pro cess contains very few impurities, and these in small quantities only.- It is evident that it could not contain more than one-eighth the amount of impurities existing in ordinary illuminating-gas, as eight times the quantity of gas is made by the new process from a given quantity of coal, as is made by the ordinary process of making illuminating gas. Not only is this the case, but the sulphureted hydrogen, bisulphide of carbon, and most ofthe ammoniacal compounds formed in the distillation of coal, are decomposed in the vertical retorts, and the hydrogen they con taiued set free, while the carbonic acid is converted into carbonic oxide, a gas as inflammable as hydrogen, and both of which add to the volume of gas produced. The purification of the gas made by the new method will, therefore, cost less than one-eighth that of illuminating-gas as ordinarily made. 7

Sixth. It is'evident that, as eight times the quantity of gas is made by the new process over the old, much less room for the storage of coal is required, and much less capital to conduct the business. There is also no tar to dispose of, or deposit of solid carbon or other material to remove from the retorts and pipes in the manner practiced in the old process of gas manufacture; besides, the new method is in nowise a nuisance to the neighborhood in Which the gas is produced.

Seventh. The gas produced by the new process, though consisting of a variety of gases products of these substances into of different specific gravities, becomes (accordmg to the well-known law of difl'usion of gases) perfectly mixed-that is, they iutermiugle with each other throughout the entire body of .the gas, so that the free hydrogen present, though lightest of all the gases, exists in uni form proportions throughout the entire gase ous body.

These gases are also permanent in their character, and, therefore, not condensable by cold or ordinary pressure in the holder or pipes, as is the case with the luminiferous constituents of ordinary coal-gas, which constitutes a very serious waste of the very best light-producing elements existing in the gas.

Advantages and Economy of Infiamnmble Gases Over Ordinary Fuel.

It is a well established fact that a small proportion only of, the heat-producing elements is utilized in the use of ordinary fuel.. This is the result of imperfect combustion of these elements. Perfect combustion of fuel cannot be obtained without flame, and no form of fuel can be made to produce flameunless first converted into gas. The temperature of an ordinary fire from bituminous coal, wood, or peat is too feeble to convert the entire volatile gas, and hence a very large proportion of the heat-producing elements they contain is wasted.

The burning of wood, peat, or bituminous coal, as ordinarily practiced, is .a process of simple distillation in contact with the atmosphere by which the fuel is mainly converted into smoke, aqueous vapor, hydrocarbon vapors, and gases.

These vapors and unoxidized carbon or smoke and carbonic acid, when mingled with the inflammable gases generated, so far envelop them as to partially obstruct the free contact of the oxygen of the atmosphere with the gaseous body, so that a partial combustion only of the inflammable gases themselves takes place, while the vapors and smoke not only escape combustion but also become a vehicle for the transmission of a portion of the heat by the flue;

In burning anthracite coal, charcoal, or the coke of gas-houses, a flame is produced whenever the supply of oxygen is sufficient to form carbonic acid beneath the mass of ignited coal. The first eflect of combustion of anthracite coal is a glow'of flame, the form of which is scarcely visible, and, as the carbonic acid passes up through the red-hot coal, it ischanged into carbonic oxide, by taking up an additional quantity of carbon equal to that p it already contained. This gas, when exposed to the free action of the atmosphere, takes fire above the bed of coal, and burns with a visible flame; but, if the supply of oxygen is insufficient to form carbonic acid at the bottom of the ignited coal, then a slow combustion takes place, resulting directly in carbonic oxide, which, without a sufficient supply of oxygen, escapes combustion, and is carried on by the flue and wasted, as a heat-producing agent, as truly so as though it were wood or coal scatt'eredfto.the'gwinds by a continuous process; so that the ordinary use of even an thracite coal forms 110 exception to the rule of imperfect combustion and consequent waste of the heat-producing elements contained in crude fuel. To economize the heat-producing elements contained in ordinary fuel, they must first be isolated in the gaseous form out of contact with the atmosphere, and afterward burned, so as to secure perfect combustion, which results in theformation of carbonic acid and aqueous vapor.

The gas made'by the new process is dry and perfectly free from condensable matter of every kind, and, therefore, capable of rapid and perfect combustion, producing, without dust, soot, or ashes, a'hot smokeless flame that may be disposed .of at will by merely turning 011' the gas when the heat is not required. A'great number of burners and other appliances for the use of inflammable gases as a "source of heat isalready in'existence, and

new inventions for this purpose are almost dailyadded to the list, and, therefore, it is not necessary here to describe any particular method for burning inflammable gases. The

gasmade by the new method maybe conveyed through'pipes to customers the same as illuminating-gas, and is applicable to industrial pursuits, and also to all the various purposes of domestic life requiring artificial heats It may be compressed andused in locomotives with great economyand convenience, and by which the terrible nuisance of smoke, cinders, and poisonous gases,'which produce so much discomfort and sickness among passengers in rail-cars, may be avoided; The. gas generated on board ofvrocean steamers, and used for generatingisteam, and for other purposes requiring heat, would be the means of an immense saving of coal, as

it would not require half the quantity that is nowused to produce the same results.

By-thenew'pro'cess, the gas may be made so as to be wholly free from bicarbureted hydrogen, and, in this form, well adapted to metallurgical and chemical purposes, especially in connection with oxygen in producing the oxyhydrogen flame. I

' With the recent facilities for obtaining oxygen, this gas may be employed for the production of the oxyhydrogen light so cheaply that this light may be employed for many purposes withrgreat ecouomyand convenience.

Claims;

What I claim as my invention, and desire to secure by Letters Patent, is----- p The process herein described of manufacturin g gas-fuel from bituminous coal or equivalent crude fuel, by subjectingits distillates to the action of high heat, not. less than 2000 Fahrenheit, in the manner and by the means herein specified, whereby such distillates are decomposed into hydrogen and carbonic oxide. i

Witness my hand this 8th day of November, 1872.

WILLIAM ELMER, Witnesses:

J. P. FITCH, A. LIVINGSTON MILLs.