US2205554A - Method for generating oil gas - Google Patents

Description

\- June 25, 1940. M, M. BRANDEGEE Er AL 2,205,554

lETlHUD FOR GENERATING DIL GAS Original File'd Dec. 16.1935

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` `IN'ENT Rsv Monms M RAoe-Gee GER CHARLE E. HEM

Patented June 25, 1940 l f 2.205.554 v amm Y nm'rnon `son aanname oiLGAs arm-is M. annonce, riainiieid', ma chai-ies ii.'V Hemminger, Westfield, N. I., assignors 'to Oomimiinn Utilities corporation, New york, is. Y..

a corporation of Maine y n December' ifs, i935, serial No. 54,704-

Applicatie Glaiiiml This invention relates to` the' manufacture of combustible gas and more particularly concerns an improved'method of generating gas having a wide range of caloriflc value and specific gravity for use in industrial and domestic heating. y A'A particular object of the present invention is to meet the demand for a plan whereby existing three-shell 'water gas generating sets of small capacity (i. e., below the so-called seven foot n sets) may be converted for operationfas oil gas generators without any considerable expense to the owners. Another object is to provide 'simple operating cycles on which such small water gas e sets may be operated as oil gas generators with.-v out the use of expensive automatic controls by.

operators of average skill and'ability. Another object is to provide a planwhereby such small watergas sets may be converted for operation with oil asthe sole source of fuel for use both in n heating up the set and in generating carbureted water gas. Another object of the invention is to provide 'process steps whereby suchsmall `water gas sets may be operated efficiently on an intermittent cycle employing a relatively shorter heatlng period in relation to the gas makingperiod than is usually used.

A feature of the invention resides inthe use in the carburetor ofa water gas set of a carbon filtering screen of small uniformly sized ceramic 1 n brick in place of the usual Achecker brick, and inv the employment of the screen as the Aprincipal high temperature oil cracking and gas generating zone of the apparatus during the gas making periods. Another important feature of the invention consists in a novel design of combinedA u oil spray and forced draft oil burner unit which v is mounted above the ceramic screen in substantially the vertical axis thereof such` unit and the relative positioning of its parts being such as to insure uniform heating of all sections of the ceramic screen and uniform spraying of oil thereover during the gas making pey riod.

. With the above and other objects and features u lin view, the invention consists vin the improved process for making carbureted water gasfwhich vis hereinafter described and more particularly i defined in the accompanying claims.

In the drawing forming a part hereof a Apre-- ferred 'form of the apparatus is illustrated inwhich: n i

Fig. 1 is a somewhat diagrammatic view in vertical section of a three-shell water gas set which has been modified to' include ceramic screens,

u combined forced draft oilburner and ofi spray` the design Qf -be produced by the-plan of operation. temperatures as high as 2000 F. may be devel- Renewed September 14, 193.91`

units, and connections whereby the set may y'Jperted in accordance with several different' op- .erting cycles. .i s

Fig. 2 is an enlargeliviempartly in elevation and partly in vertical;` section, of the upper por- I tion of a gas generator equipped with acombined .forced draft oil burner and oil spray unit whichl forms one of the principal apparatus elements of v the present invention. f

3 isv a `somewhat diagrammatic plan'A view .1'.

ofthe top ofthe gas generator (with parts brofken away) showing -how primary aii is admit-v ted at 4a controlled rate tangentiaily to the oil j burnerat the to of'the, generator.

Referring to n designates a gas generator which is connected at its top through conduit I2 with a carbureter I4. 'I'he v carbureter is connected at its base through e conduit l'with a superheater Il. A conduit Il contraires by a not valve :z connects the base ci p generator 'lli with the base of carbureter Il. Another conduit 2l controlled by a' hoi'. valve 20 connects the base of the generator with conduity i2 and the top of vcarbureter I4. A`hot valve Ilv 'ls mounted in .conduit I2 at a point between genf u erator Il and the Junction of conduit 24 with conduit I2. yAnother conduit It equipped with a -valve 12 'leadsoiifroi'n the. upper part of super# heater Il to a wash -box il, anda gas otake Vline I6 is ported out iroxrithe` wash. box. ,The top or superheaier is has a hinged siaek'vaive u*A opening into the base of a stack Il. Another conduit 42 controlled by a hot valve connects the base of the generator directly t the' wash boxed 1 Generator Il lis provided at a point above the level of conduits 2Q and 4K2 with a refractory.v checker brick arch Lupon which is supported a bed of ceramic material which vmay be three to iive feet in depth and which mayA consist'pariiauy 'of checker brick It and partially of uniformly 5 sized 'small 'ceramic bricks or balls Il. The' carbureter I4 is also .provided near itsl base .with a refractory checkerbrick arch 50 lupon which is supported a carbon. filtering and crackingy screen composed partly of checker brick I2 and partlyv u of a bed of small substantially uniformly sized ceramic bricks or balls Il. I'he ydepth of the screen Il is, preferably in the neighborhood ci?y two to Vthree feet,- this depthvarying 'somewhat o depending upon the character of vgas which is to v Since opedon the surfaces of the-,refractory inthe generator and carbureter vscreens 46, 4l, 52 and y g. 1 of the drawing, numeral i u 54, these screens are preferably composed of Mullite or similar high alumina. ceramic material adapted to withstand spalling due to' the alternate heating and cooling. The individual ceramic bricks or ballswhich make up the screens 48 and 54 are preferably sized so that their maxf imum linear dimensions or diameter lies in the range two to three inches.

The base of the generator III is provided with a valved primary air inlet 56 adjacent which there is also mounted an oil burner il. A specially designed combination forced draft oil burner and oil spray 6l! is shown astmounted at the top and in the vertical axis of the carbureter I4. Air for operating the oil burner element of the unit 60 enters the unit tangentially from a valved air connection 62. A similar combined oil spray and oil burner unit 64 is shown as mounted at the top of generator I Il in the vertical axis thereof and as receiving air for its operation from a valved air supply conduit 6I. A valved air supply line 68 opens into the top of the superheater It, and valved steam supply lines 1li and 12 open lrespectively into' the base ofthe generator and into the top of 'the superheater. y

As illustrated particularly in Figs. 2 and,3,the combined'il'burner and oil spray units il and i4 f which are shown in Fig. las mounted vertically y'at the top of the generator andcarbureter units,

comprise an outer cylindrical shell or T 14 having especial tangential sldje imei 1s for air from one of the valved air supply pipes 62 and 86. The velocity at which air Venters the T 1I` through opening' 16 is controlled by means ofa butteriiy damper 18. The bOttOm Outlet 0f T Il is bolteda to fthe `usual top carbureter nozzle and/or to the fuel charging inlet at the'. top oi the gas generator element oi' f a standard set. Axially mounted within'thel T 14and supported ,by a

ilange closure 19 for the top of the T, is a steam atomizing oil burner Il to which `oil is supplied by, a'valved oil pipe B2, and steam by a valved steam connection 8l. A multi-nozzle rosettei-type oil spray 86 is suspended concentrically around and closely adjacent to the 'burner 20, the carbureting oil being conducted to the spray through a valved oil supply connection Il.

The combined burner and oil spray is kept cool by purging the burner with steam during periods of gas make, and by circulation of cooling water through a water cooling chamber Sl concentrically mounted around theoil spray and oil burner and within the T 14. Additional cooling of the burner and oil spray is provided by the air which is admitted to the annular air supply chamber 92 which surrounds the oil spray within the T 14, during periods when burner is operating. Cooling water is supplied to chamber through a pipe 9| and is removed therefrom through a pipe 96.' l

The damper 18 in the air supply conduit affords'the means for controlling the velocity at l which theair enters the annular chamber 02, and consequently the degree of turbulence with' which `'the air whirls about the nozzle of oil burner ill as the air enters the gas generating chamber at the top of generator I0 and/or carbureter Il. By adjustment of the damper 18, flames may be secured at the nozzle of burner 80 which vary from short sharp balls of fire immediately adjacent the nozzle to a long diffused semi-radiant ilame projecting downwardly to the top of the underlying refractory screen. Since the oil burner` GII is mounted coaxially withinthe of the units 60 and 64; the burner being provided lwith a stuiling gland 9| for the purpose of preventing the escape of gas under pressure around the burner tube.

By the concentric arrangement of nomles |00 of the oil spray 486 about/the burner the oil `for use in generating make gas or in carbureting make gasis delivered to the generator and/or carbureter in its vertical axis with uniform dis- "persion'and with any degree of atomization and rate of supply required, without disturbing the Gas operated pilot burners Ill' are the oil burner elements particularly during periods when the apparatus isA starting up.

According tol one preferred operating cycle e which will now be described, some'of the apparatus elements -illustrated in Fig. 1 `may be omitted, namely theconnections 20, 2l and l2 withtheir hot valves,hot valve 28, the oil burner (but not the spray) elementof the unit Il 'at the top oflgenerator I0,` as also the small refractory brick portion Il ofthe ceramic screen in the generator. In place of the generator fuel bed a three to five foot depth of checker brick is supported on the refractory arch M at a suiiicientheight above the base of the generator to form "a combustion chamber below the arch.- For control purposes. thermocouples 104 are mounted below the screen in the carbureter, and in the superheater. The only operating valves required for this cycle are the stack'valve. two air valves, an oil valve, and a steam valve; any other valves,

as the steam atomizing valves forthe oil burners,

being mechanically tied in with other valves.

During the heating cycle the burner 5l at the base of the generator is operated simultaneously with the oil burner element of the unit ll atthe' top of the carbureter. Suiiicient excess air is admitted to the set through air inlets 56 and 62 to4 insure combustion of any carbon residue remainfrom the generator in series through thecarbureter and screen 5I and thence through the superheater to the wash box and out to storage through offtake 3G. At the end of the make run the oil supply to the generator and carbureter` is cut oit. and the set is purged of oil gas andV vapor by continuing for a brief period the supply. oi steam to the base of the generator through steam inlet 1l. After' the steam purge the cycle isrepeated by cutting oi! the steam supply. openf cycle just previously described, in whichy the checker brick 45 of the generator is changed so4 as to include a middle section of small sized in passing` through the generator and carbureter screens is converted into a mixture of oil gas and its air supply, followed by the second burner and air supply located at the top of the carbureter.

When operating on a cycle such as thatjust described, the caloriiic value of the 'make gas produced is regulated largely by the temperatures 'which are maintained vat the bottom of the carbureter and in the superheater. These temperaheatershou'ld be maintained in the range .1650 F.

to 1750 F. ,For making a 1000 B. t. u. gas, the al#-vv lowable temperature range for the base of-the carbureter and the superheater is between 1500? F. and 1650" F. The Oil which is introdced'to generator` I0 is vaporized and partiallyl cracked in anatmosphere of steam which has been prel l L generator-'and carbureter, do not drop below a heated by passage through thegeneratorchecker brick 46. The oil vapors and any oil gas produced` in the generator pass therethrough into the .t0n

of the carbureter where it forms an atmosphere within which the oil introduced to the carbureter er brick in the generator is only slightly cooled by the small quantities of steam which are passed therethrough during the gas making run, and ac.

cordingly this checkerbrick is'maintained at'a sufiicient temperature to serve as an igniting surface for the primary air and atomized o'ilfintroduced beneath the generatorarch M, during the heating-up period. Any carbon residue on thek generator screen and on the carbureter screen is consumed by reaction with excess air introduced into theapparatus during thevblowing-up l period. l f y Another modified cycle l ferent apparatus setup than that required for the broken ceramic bricks or balls I8, thereby result-V ing in a generator of the type illustrated having a screen corresponding to the carbureter screen. For this cycle the cross connection 20 between the base of the generator and the base of the carbureter is also required, as is also the complete forcedl draft oil burner and oil spray unit M which is illustrated at the top of the generator in Fig. 1 ofthe drawing. When operating in accordance with this cycle hot valve 28 is closed, or else a blank flange is introduced at the location of the Y hot valvein conduit I2.

'I'he heating period according to this second 'process cycle, starts with down heating of the are then passed from the base of the generator -and the base of the carbureter into and upwardly through the superheater checker brick, and out of the stack; On completion of the heating `pe riod, the air and oil supplies to the burners aty the top of the generator and 'carbureter are cut off and thestack valve 38 ls closed, after which steam is admitted to the tops of both the generator and the carbureter, with simultaneous admissionof oil through the voil spray elements of units Il and Il. The mixture of oil 'and steam employs a slightly dif- The products of combustionl water gas by cracking ofthe oil and reactionoi Vthe steam with carbon produced on cracking, and` the makegas is then conducted Athrough thel checker brick-of the superheater and thence' f through the wash box and offtake` 36 to storage.

The make Acycle is followed by a down steampurge during which'steam alone is introduced to both 'the carbureter and vgeneratorthrough v`the oill yspray and burner parts of units Gland 64., This results in al down st'eam purge of boththe gen` erator andthe carbureter, with removalof the watergas produced on the purge 'through the Y wash boxand oitake 36 to storage. The steamV 'is thencutfoif and theheating cycle repeated.-

The make cycles )inderthis plan of operation have to be short in order that the temperatures in the point at vwhich there would be no ignition of the gas making capacity of theset by operation of both the generator and the carbureterfiniparallel' as twin screen generator units.` The principal "dis- 9 vatomized oil introducedjthroughthe oilburners during the heating-up period. This second cyclehas the advantage ofconsiderably increasing the yadvantage over the cycle first described is the4 f slightly lower neatunuzanon emciency and-tinerv` more 'complicated apparatus requirements.v 'Aci cording toeither ofthe operating` cyclesjust described, the steam requirements 'arerelativ'ely low *L and the gas produced accordinglyfhas vdesirable 1 characteristics, having a relatively high methane ycontent and='lower hydrogen and carbon monoxide r content and lower gravity, than the usual type of mixed oil gas and water gas.

According I`toa`third plan-foi operation, the

'cyclewouldrbe substantially'the saine' as thaty just described exceptthat ytheapparatus would include connectiont 2l vbetween thev base of the generalioll 'and the top of the"carbureter,"andy -wouldl omit 'the connection 20 betweenthe base of the generator and the base of the"carbureter.1 The'operating cycle vwould then'..be 'the' same except-lt'nat the blowjgas and Vmake gas produced in the generator would iiow in series' through the parallel with gases produced in the carbureter.

vcarbureter and carbureter screen rather than in According to a fourth plan'of operation, a relay tively low B. t. u. gasoi' 'say 550 B.` t. u. and .68 gravity can rbe made from low gravity bunker C f fuel oil' by firstproducing an oil' gas 'of approxi- 'mately .750 B. t. 11.and then' diluting with a mixture oi' blow run gas and blue vgas. Par't 'off lthe heat for the set can then be obtained by combustion (during the heatingcycle) of carbon resulting from the cracking of the high gravity highcarbon oil used during the make cycle. Acy Vcording' to this `fourthfplan o ffoperation, a hot ,valveforback run set may be employed having an oil spray-in the topof the generator,'but i without requiring the forced draft oil burner ele-- ment ofthe unit Il illustrated. Shallow screens of'small refractory ll,V 5I, are preferably employedboth in thegenerator and in the carbureter. 'During the make period, allthe oilvre- .quired lto produce make'gas issprayed into the top'of the generator vwhere'it is vaporized by the to form water gas. Heating up of the generator and carbureter between make periods is effected by means of the oil burner at the base of the generator, supplemented by combustion of carbon 5, deposit on the refractory screens with excess air. In a hot valve set the cycle begins with the stack valve Il open andwith supplyof primaryV air to the base of the generator and secondary air to the top of the carbureter. The heating-up 1o period is suspended when the thermocouple at the base of the carbureter reaches a reading of 1600 F. to .1700 F. 'Ihe stack valve and the primary and secondary air supplies are then turned ofi' and steam is introduced to the base l5 of the generator, and heavyoil is dmultaneously sprayed into the top of the generator. The mixture of steam and oil vapors passesfrom the top of the generator into the top ofthe carbureter and thence downwardly through the lrefractory 2o screen inthe carbureter and upwardlythrough the checker brick in the superheaier into the wash box. Cracking of the oil takes placclargely in the zonevof the carbureter screen.` At the end p -of the oil run the oil supply is cut of! and the.

25 apparatus is purged by continuing the supply of steam 'through the steam supply pipe 1I. Before opening the stack for the next heating cycle a short blow purge is carried out by closing the steam supply at 1l vand opening the air supply It for a brief period during which air blast gases are carried through the set to the wash box and are then conducted to the holder.

A fifth operating cycle may be carried out in the set illustratedI in which the principal change in operation is that which makes use of the back run connection 42 directly. from the base of the Agenerator to the wash box. 'nie heatingand make cycles are similar to those just described for the fourth plan of operation, but during the 4Q steam purge cycle steam is introduced through connection 12 to the superheater. Gasproduced during a reverse steam purge is conducted directly from the base .of the generator to the wash box. A reverse air purge follows the reverse steam I purge during which air is'introduced to the superheater through the connection Il and the reverse blow gases are conducted directly from the base of the generator to the wash box, and thence to storage. The next` heating-up opera- ,50 tion is started after closing the air valve in the top oi' the superheater and opening the stack valve. and after closing the valve in connec-V tion 42.

Having thus described the invention what is v55 claimed as new is: 1. An improved cyclic process of making mix oil gas and water gas in apparatus comprising a single gas generator having therein a high t'em- 70 heater, and between periods of the heating spraying oil simultaneously intov the tops of the generator and carbureter while simultaneously introducing steam into the` base of the generator and passing the mixed steam and oil vapors .u through the carbureter and super-heater i track www?? a,aos,ssa

the oil and produce amixture of cracked oil gas and water gas.

2. An improved cyclic process of making mixed oil gas and water gas in apparatus comprising a singlegas generator having therein a ,high temperature carbon ltering screen of small uniformly sized ceramic brick, a single carbureter having acarbon filtering screen of small uniformly sized ceramic pieces supported transversely thereof, and a single superheater, which comprises periodically heating up the apparatus by burning oil simultaneously in the top of the gen-` erator and in the topof the carbureter andpass- L ing the products of combustion in parallel downwardly through the generator screen and car-` il bureter screen, respectively, and thence through 4the superheater. and between heating periods spraying oil and steam simultaneously into the top of thjeshot generator and carbureter, passing the oilvapors and steam downwardly inparallel y through the ceramic screens in the carbureter and generator to crack the oil, and passing the generated oil gas and water gas into and through the superhe'ater.

3. An improved cyclic process of makingmixed gg oil gas and water gas in apparatus comprising a single gas generator having therein a high temperature bed of ceramic brick. a single carbureter having a carbon filtering screen of small uniformly sized ceramic `pieces supported transversely n thereof, and a single superheater, -which com- Y prises periodically heating up the apparatus by burning oil simultaneously in the generator and in the carbureter a'nd passing the products of combustion in admixture with sumcient excess Il lair to burn of! deposited carbon, inseries upwardly through the ceramic `bricks of the generator, downwardly through the ceramic screen of the carbureter and into and through the superheater, and between periods of heating sprayu ing high gravity oil into the top of the generator while simultaneously passing steam upwardly through the ceramic bricks of the generator, passing the mixture of steam and oil vapors. together with any water gas formed in the generator, u through the carbureter screen, thereby cracking `the oil, and pdssing the mixedwater gas and oil gas through the superheater, and before begining the next heating operation purging the apparatus with a short forward steam run followed by a short air-blow purge inthe same direction.v

4. An improved cyclic process of making mixed oil gas and water gas in apparatus comprising a single gas generator having therein a high temperature bed of ceramic brick, a single carbureter u having a carbon filtering screen of small uniformly sized ceramic `pieces supported transversely thereof, and a single superheater, which comprises periodically heating up the apparatus by burning oil simultaneouslyV in the generator .o and in the carbureter and passing the products of combustionin admixture with sumcient excess air to burn oi! deposited carbon. in series up, wardly through the ceramic bricks of the generator, downwardly through the ceramic screen of ,5 the carbureter into `and through the superheater, and between periods of -heating spraying high gravity oil into the top of the generator while simultaneously passing steam upwardly through the refractory bricks of the generator, passing the mixture of steam and oil vapors together with any water gas formed in thegenerator through the carbureter screen thereby crackingtheoil, and passing the mixed water gas and oil gas the superheater, and before beginning 7.

the next heating operation purging the apparatus with a. back steam purge in series through the superheater, carbureter and generator iv'ollowed by a short reverse air-purge through the same path followed by the steam purge.

5. An improved process of making mixed oil l and water gas in an apparatus comprising a single gas generator having therein a bed ofl ceramic brick, a single carbureter, and a single superheater, which comprises periodically heating up the apparatus by burning oil simultaneously in the base of the generator and in the top of the carbureter' and passing the products of combustion in series upwardly through the .ceramic brick o! the generatorvand downwardly through the carbureter and thence through the superheater and between periods of heating spraying oil simultaneously into the tops of the generator and carbureter while simultaneously introducing steam into the base of the generator and passing the mixed steam and oil vapors through the car-Y bureter and superheater to crack the oil and produce a mirture of cracked oil gas and water gas. Y

6. An improved cyclic process of making mixed oil gas and water gas in apparatus comprising a single gas generator having therein a high temperature carbon filtering screen of small'vunithrough the generator screen andl carbureter,

respectively, and thence through the superheater,l and between heating periods spraying oil and steam simultaneously into the top ot the hot generator and carbureter, passing the oilvapors and steam fdownwardly in parallel through the 'carbureter and generator to crack the oil, and

passing the generated oil gas and Vwat'ergas into. and lthrough the superheater.

, v MORRIS M. BRANDEtiEE;\V CHARIES E. GER.

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