US1891890A

US1891890A - Method of making asphalt

Info

Publication number: US1891890A
Application number: US291601A
Authority: US
Inventors: Jr Percy C Keith
Original assignee: Gasoline Products Co Inc
Current assignee: Gasoline Products Co Inc
Priority date: 1928-07-10
Filing date: 1928-07-10
Publication date: 1932-12-20
Anticipated expiration: 1949-12-20

Description

Dec. 20, 1932. p KElTl-LJR 1,891,890

METHOD OF MAKING ASPHALT Filed July 10, 1928 (Hum MM:

Patented n... 20, 1932' UNITED STATES PATENT or fice;-

PERCY c. .xnrrn, 3a., or BEBNABDSVILLE, NEW mnsnir, assienoa, BY men; as-

sremrmrrs, TO GASOLINE PRODUCTS COMPANY, INC OF A CORPORATION OF DELAWARE NEWARK, NEW JERSEY,

mnon OF MAKING ASPHALT Application filed July 10, 1928. Serial No. 291,601.

This invention relates to the roduction of commercial asphalt from cradkingcoil tar and will be understood from the following description read in conjunction with the drawing which is an elevation principally in section of apparatus in which my method'may be carried into effect.

Petroleum oil to be cracked is introduced through the 'ipe 1 controlled by valve 2 to the tubular eater 3. The tubular heater consists of a number of sections of tubing joined end to end by cross-over connections to form a continuous circuit. It is surrounded by the refractory setting 4 and may be heated through port 5 by means of the burner 6. The heating is 'so conducted that the material is heated to a relatively high temperature, usually above 800 F., and is then discharged through pipe 7 into thedigestion chamber 8. This consists of a drum, preferably-surrounded by insulating material 9, in which the cracked petroleum oil is retained for a further period durin which cracking reactions proceed, principa ly as a result of the contained heat. The precise form of tubular heater and digestion drum are unimportant; any alternative type may be employed in place of those specifically illustrated. The tubular heater is known in the trade as a cracking coil and will be hereinafter referred to as such. Ordinarily the coil and drum operate under pressure considerably in excess of atmospheric, frequentl as high as several hundred pounds gauge, w ich may be reduced at the outlet 10 by a reduction valve such as 11. The cracked material which is continuously abstracted from the digestion drum is introduced at reduced pressure, say 15 pounds gauge or less, into the low pressure drum 12 through the pipe 11a. The cracked material is preferably discharged into this drum through a perforated pipe such as 13. Separation takes place in the drum 12, tarry material collecting in the lower part thereof while vapors which are substantially tar free pass off overhead through the pipe 14. When operating under extremely high pressures in the coil and drum, or during vapor phase operation, it is frequently advisable to introduce petroleum oil with the cracked gnaterial, which may be done by means of the oil inlet pipe 15 controlled by valve 16 and discharging into pipe 11a. While any oil introduced in this manner will absorb the super-heat of the cracked material and control the consistency of the tar produced, it is desirable to introduce through the pipe 15 an oil containing tar-forming constituents which will add to the tar produced by cracking and the additional benefit will be simultaneously derived in separating the tar-forming constituents from the oil so introduced. The vapor passing oii' through 14 enters the rectifying column 17. This consists of any suitable type of rectifying equipment; that shown is provided with the conventional partitions which carry over-flow pipes and vapor distributors of any suitable character, not shown. Condensation is produced by cooling coils in the upper part of the tower such as 18 and 19. The C011 19 may conveniently be supplied with oil for the crackingcoil which is thereby pre-heated prior to cracking. The total amount of cooling obtained by the use of

coils

18 and 19 is preferably so controlled that the final vapor passing ofi through the pipe 20 consists essentially of gasoline which may then be condensed and worked up for the market in any approved manner. Aliquid bottoms collects in the base of the tower 17 and is preferably withdrawn continuously through the pipe 21 and pumped by means of the pump 22 through the pipe 23 controlled b valve 24 back into the cracking coil, there y recirculating the 35 said bottoms and adding to the total quantit of gasoline produced. The drum .12 is re erably surrounded by insulation 12a an the tar collectingin this drum is withdrawn continuously or eriodically by means of the pipe 90 25 controlled by valve 26 and thereby d18- charged into the intermediate portion of the stripping drum 27. The pi e 25 is preferably surrounded by insulation 26a so that the tar may be introduced substantially without loss of heat into the intermediate portion of the drum 27. This drum carries horizontal partitions 28 equipped with the customary vapor distributors and over-flow pipes, not shown, below the point of introductor 33. The drum 27 preferably carries.

foraminous plates 34 above the point of introduction of the tar, which may in turn carry tile or other bafiling means, not shown, to knock down entrainment from the ascending ..vapor. Vapors may be conducted from the drum 27 through the vapor pipe 36 which discharges into the condenser 37. This condenser consists of an elongated drum provided with water inlet 38 at the lower end and water outlet 39 at the upper end. A number of tubes 42 are arranged within the drum between the two

header plates

40 and 41 so that the water circulates within the tubes 42.

Any oil va or discharged b the pipe 36 circulates in t e space externa to the tubes and is thereby condensed. The condensate is continuously withdrawn through the pipe 44 discharging into the accumulator 45 .from which it may be continuously or periodically withdrawn by means of the pipe 46 connected to the pump 47 and thereby diverted through the pipe 48 to any suitable accumulator. By means of the pi e 49 connected to the accumulator 45 and t e vacuum pump 50 the condenser 37 and drum 27 are maintained under vacuum. The vacuum pump 50 may be of any suitable t e although that illustrated diagrammatical y is barometric. .The operation of the cracking coil will be obvious to those familiar with the art. In 0 erating theequi ment for the reduction 0 the tar produc by the cracking equipment a vacuum is applied through the condenser 37 to the tar discharged into the drum 27. I preferably employ a. vacuum corresponding to an absolute pressure of less than 100 mm. of mercury. This automatically results in a considerable reduction of the tar delivered by the pipe 25. In consequence of the retained heat of the tar this is distinctly assisted by the fact that the tar when brought from the cracking system may be at a temperature of 700 or 800 F. The reducing effect of the vacuum ap lied to the heated tar is further augmente by the strip in effect of the steam introduced through t e istributor 33 and the additional heat applied by means of the coil 30. The coil 30 is preferably supplied with super-heated steam for this purpose. The effect of these agencies is so controlled as to roduce a li uid residuum in the bottom 0 the drum 2 corresponding to a commercial asphalt. By means of the overflow pipe 51 the level of this material in the bottom of the drum 27 is maintained above the coil 30, any excess being continuously diverted through the overflow pipe 51 controlled by valve 52 and transferred by means of the pump 53 to'any suitable accumulator. The

ade of material produced may conveniently include all of those products which are generically covered by the term asphalt and which range from the liquid or semi-liquid products known as bindersdown to the productswhich are solid at normal temperatures and which constitute asphalts of relatively high melting oint and low penetration.

The foregoing specific illustration of my method is by way of illustration and not of limitation. Itis my intention that the invention be limited only bythe a pended claims, or their equivalents, in whic I have. endeavored to cover broadly all inherent ndvelty.

I claim:

1. The method of reducing tar residuum produced by heating petroleum oil,- under pressure, ina confined stream to a cracking temperature, retaining the cracked material, under pressure, in' a digestion zone, continuously withdrawing cracked material from the digestion zone and discharging it into a zone'maintained under reduced pressure to produce a first vapor and 'a tar residuum, which comprises continuously discharging the tar residuum without substantial loss of heat into a zone maintained under vacuum,

stripping the material in said zone maintained under vacuum to the extent necessary to produce aresiduum of commercial asphalt.

2. The method of reducing tar residuum produced by heating petroleum oil, under pressure, in a confined stream to a cracking temperature retaining the cracked material, under pressure, in a digestion zone,-continuously withdrawing cracked material from the digestion zone and discharging it into a zone maintained under, reduced pressure to roduce a first vapor and a tar residuum w ich comprises continuously discharging the tar residuum without substantial loss of heat into a zone maintained under vacuum to produce a second vapor and a liquid residuum,

- contacting the liquid residuum counter-cur-.

rently with steam to the extent necessar to produce a residuum of commercial as alt. 3. The method of reducing tar resi uum produced by heating petroleum oil, underpressure, in a confined stream to a crackin temperature, retaining the cracked materia under pressure, in a digestion zone, continuously withdrawing cracked material from the digestion zone and dischar ing it into a zone maintained under reducec l pressure to produce a first vapor and a tar residuum which comprises continuously discharging the tar residuum without substantial loss of heat into a zone maintained under vacuum to produce a second vapor and a liquid residuum, heatin the liquid residuumin said zone maintaine under vacuum and counter-currently contacting steam therewith to the extent necessary to produce a residuum of'com-- inercial asphalt.

sure in a confined stream to a crackin tem-- gerature, retammg the cracked materlal un- 4. The method of making asphalt which comprises heating petroleum oil under pressure in a confined stream to a cracking temperature, retaining the cracked material under pressure in a di stion zone, continuously withdrawing crac ed material from the digesting zone, combining therewith petroleum oil containing tar-forming constituents, discharging the combined materials into a zone maintained under reduced pressure to pro-1 duce a first vapor and a tar residuum and continuously withdrawing the tar residuum without substantial loss of heat to strip the sailmf to produce a residuum of commercial asa t. a

p 5. The method of making asphalt which comprisesheating petroleum oil under preser pressure in a digestion zone, continuously withdrawing cracked material from the digestion zone, combining therewith petroleum oil containing tar-forming constituents, discharging the combined materials into a zone maintained under reduced pressure to produce a first vapor and a tar residuum, continuously withdrawing the tar residuum and discharging the same without substantial loss of heat into a zone maintained under vacuum, stripping the tar residuum in said zone maintained under vacuum to the extent necessary to roduce a residuum of commercial asphalt. n testimony whereof, I have signed my name to this specification this 5th day of July, 1928.

PERCY O. KEITH, JR.