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US4284616A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for recovering carbon black and hydrocarbons from used tires

Assignee: Intenco Inc
•
Filing: 1979-01-15
•
Granted: 1981-08-18
•
Expires: 1999-01-15
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Abstract

Abstract The invention is a process for economically recovering carbon black, oil and fuel gas from used tires. Used tires are physically fragmented. The fragments are pyrolized at slightly subatmospheric pressure in a reactor while process char is being recycled to increase heat transfer and avoid coke on heat transfer surfaces. Entrained char is separated from the vapor phase products of the pyrolysis, and the vapor phase products of the pyrolysis are then fractionated into oil and fuel gas. A preferred embodiment condenses reactor vapors in two stages at two temperature levels to separate dust from an oil-dust mixture, without water in the first stage and light oil in the second stage. The fuel gas can be compressed and burnt to provide process heat. The entrained char dust and some heavy oil is returned to the reactor. Solid phase pyrolysis products are stripped of trash and milled to carbon black. Carbon black is mechanically separated from the effluent air stream of the mill and formed into pellets with added water and dried.

Inventors

  • 👤 Age Solbakken
  • 👤 Fred P. Apffel
  • 👤 Sam P. Robinson
  • 👤 Bobby L. Hayes

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 14:02
CPC Classifications
B; B29; B29B; B29B17/00; B29B17/02; C; C09; C09C; C09C1/00; C09C1/44; C09C1/48; C09C1/482; C10; C10B; C10B47/00; C10B47/18; C10B47/26; C10B53/00; C10B53/07; C10G; C10G1/00; C10G1/10; B29B2017/0213; B29B2017/0268; B29B2017/0272; B29B17/04; B29B2017/0424; B29B2017/0496; B29K; B29K2707/00; B29K2707/04; B29L; B29L2030/00; C01; C01P; C01P2004/00; C01P2004/50; C01P2006/00; C01P2006/12; C01P2006/19; Y; Y02; Y02P; Y02P20/00; Y02P20/141; Y02P20/143; Y02W; Y02W30/00; Y02W30/50; Y02W30/52; Y02W30/62

Claims Analysis

Total Claims: 39
Claim 1
Independent Claim 92 words
A process for manufacturing carbon black and hydrocarbons from discarded tires, comprising: cutting the tires into fragments; pyrolyzing the fragments in a pyrolysis reaction vessel at a temperature and pressure and for a reaction time sufficient to cause the fragments to dissociate into a vapor phase and a solid phase; recycling a portion of said solid phase back into the reactor; said pyrolizing step including indirectly, internally heating the fragments in the reaction vessel with molten salt; producing carbon black from the solid phase; and processing said vapor phase to produce hydrocarbons.
Claim 2
Dependent Claim 92 words
A process for manufacturing carbon black and hydrocarbons from discarded tires, comprising: cutting the tires into fragments; pyrolyzing the fragments in a pyrolysis reaction vessel at a temperature and pressure and for a reaction time sufficient to cause the fragments to dissociate into a vapor phase and a solid phase; recycling a portion of said solid phase back into the reactor; said pyrolizing step including indirectly, internally heating the fragments in the reaction vessel with molten salt; producing carbon black from the solid phase; and processing said vapor phase to produce hydrocarbons.
Claim 3
Dependent Claim 26 words
A process as in claim 1 including: separating trash from the pyrolyzed solid phase after said reaction; and milling the pyrolyzed solid phase to carbon black.
Claim 4
Dependent Claim 19 words
A process as in claim 2 including: cooling the pyrolyzed solid phase after it leaves the pyrolysis reaction vessel.
Claim 5
Dependent Claim 29 words
A process as in claim 3 including: wetting at least a portion of the carbon black; forming the wetted carbon black into pellets; and drying the carbon black pellets.
Claim 6
Dependent Claim 21 words
A process as in claim 3 wherein the cooling is accomplished by passing said solid phase indirect heat exchange with water.
Claim 7
Dependent Claim 31 words
A process as in claim 5 wherein at least a portion of the water heated by indirect heat exchange with the solid phase is subsequently used to wet the carbon black.
Claim 8
Dependent Claim 30 words
A process as in claim 2 wherein milling of the pyrolyzed solid phase into carbon black is accomplished by passing the pyrolyzed solid phase through an air swept roller mill.
Claim 9
Dependent Claim 21 words
A process as in claim 3 wherein said tires contain steel reinforcing wire and said trash separation is a magnetic separation.
Claim 10
Dependent Claim 47 words
A process as in claim 1 wherein the heat is introduced through an internal, hollow shaft of the reactor having protrusions therefrom and the molten salt mixture is introduced into the rotating shaft through a rotating seal and returned from the shaft through means which are non-rotating.
Claim 11
Dependent Claim 20 words
A process as in claim 1 including initially passing the effluent vapor phase from the reactor vessel through a scrubber.
Claim 12
Dependent Claim 29 words
A process as in claim 10 wherein scrubbing of said vapor phase occurs in close proximity to the vapor outlet of the pyrolysis reaction vessel and at subatmospheric pressure.
Claim 13
Dependent Claim 43 words
A process as in claim 11 wherein a second portion of the vapor phase obtained by scrubbing a portion of the vapor phase is cooled to condense out oil and said oil is separated from the gas containing remainder of said vapor phase.
Claim 14
Dependent Claim 33 words
A process as in claim 12 wherein said oil is cooled out of the second portion of the vapor phase by passing the second portion of the vapor phase in indirect heat exchange.
Claim 15
Dependent Claim 28 words
A process as in claim 13 including: compressing the gas containing remainder of the second portion of the vapor phase to provide fuel gas for the pyrolysis reactor.
Claim 16
Dependent Claim 26 words
A process as in claim 14 wherein said compression is accomplished by the same mechanical means used to maintain subatmospheric pressure in the pyrolysis reaction vessel.
Claim 17
Dependent Claim 50 words
A process as in claim 1 wherein a first portion of the vapor phase is scrubbed and partially condensed with a cooled condensate obtained by refluxing and cooling a second portion of the vapor phase obtained by scrubbing a portion of the vapor phase in a direct contact multi-stage scrubber.
Claim 18
Dependent Claim 25 words
A process as in claim 16 wherein the scrubbing occurs in low pressure drop, venturi type scrubbers with high volume reflux of the cooled condensate.
Claim 19
Dependent Claim 15 words
A process as in claim 16 wherein the scrubbing occurs in a direct spray condenser.
Claim 20
Dependent Claim 56 words
A process as in claim 17 wherein residue is obtained by the step of removing substantial quantities of liquids of a second portion of the cooled condensate by centrifuging a second portion of the cooled condensate, the residue being substantially in the form of a concentrated carbon black and the residue is recycled to the reactor.
Claim 21
Dependent Claim 21 words
A process as in claim 19 wherein the residue is recycled by a progressing cavity sludge pump back to the reactor.
Claim 22
Dependent Claim 43 words
A process as in claim 1 wherein the pyrolyzing occurs in an oxygen limited hydrocarbon vapor atmosphere isolated from ambient air by the use of an inert purge gas seal and airlocks at the entry port and discharge port of the reaction vessel.
Claim 23
Dependent Claim 128 words
A process for maufacturing carbon black and hydrocarbons from discarded tires, comprising: cutting said tires into small pieces; pyrolyzing the pieces in a pyrolysis reaction vessel at between 750° and 1800° Fahrenheit and oxygen limited hydrocarbon vapor atmosphere at between 1-22 PSIA for between 5 and 90 minutes to produce a substantialy pyrolyzed solid phase and a vapor phase; recycling 10-80% of pyrolyzed material to the pyrolysis reaction vessel; producing a condensate from a portion of said vapor phase in said reaction vessel, such portion containing the dust entrained in the vapors; recycling the concentrated dust to the reactor; fractionating a second portion of said vapor phase to produce oil and gas; and recycling at least a first portion of the pyrolyzed solid phase into said reaction vessel.
Claim 24
Dependent Claim 128 words
A process for maufacturing carbon black and hydrocarbons from discarded tires, comprising: cutting said tires into small pieces; pyrolyzing the pieces in a pyrolysis reaction vessel at between 750° and 1800° Fahrenheit and oxygen limited hydrocarbon vapor atmosphere at between 1-22 PSIA for between 5 and 90 minutes to produce a substantialy pyrolyzed solid phase and a vapor phase; recycling 10-80% of pyrolyzed material to the pyrolysis reaction vessel; producing a condensate from a portion of said vapor phase in said reaction vessel, such portion containing the dust entrained in the vapors; recycling the concentrated dust to the reactor; fractionating a second portion of said vapor phase to produce oil and gas; and recycling at least a first portion of the pyrolyzed solid phase into said reaction vessel.
Claim 25
Dependent Claim 23 words
A process as in claim 22 wherein pyrolysis occurs for between 5 and 25 minutes at about 850° Fahrenheit and about 14 PSIA.
Claim 26
Dependent Claim 32 words
A process as in claim 23 wherein the pyrolysis reaction vessel is a hollow shaft, hollow flight vessel and the fragments are moved through the vessel by at least one screw conveyor.
Claim 27
Dependent Claim 15 words
A process as in claim 24 wherein the screw conveyor has a reduced flight pitch.
Claim 28
Dependent Claim 19 words
A process as in claim 23 wherein the reaction vessel uses a hollow flight screw with square pitch flights.
Claim 29
Dependent Claim 37 words
A process as in claim 23 wherein the pyrolysis reaction vessel contains a hollow shaft and appendages and the fragments are moved through the vessel by appendages attached to the shaft having variable, pitched attachments mounted thereon.
Claim 30
Dependent Claim 14 words
A process as in claim 23 wherein the pyrolysis reaction vessel is indirectly heated.
Claim 31
Dependent Claim 18 words
A process as in claim 28 wherein the vessel is indirectly heated by a circulating molten salt mixture.
Claim 32
Dependent Claim 37 words
A process as in claim 29 wherein the fractionating of the second portion of the vapor phase comprises: condensing at least one hydrocarbon fraction from said vapor phase; and separating said fraction from the residual fuel gas.
Claim 33
Dependent Claim 25 words
A process as in claim 30 wherein said condensate and said hydrocarbon fraction are cooled by a combination of direct contact and indirect heat exchange.
Claim 34
Dependent Claim 40 words
A process as in claim 28 wherein the hydrocarbon atmosphere in the reaction vessel is isolated from air by the use of an inert purge gas seal and airlocks at the entry and discharge ports of the sealed reaction vessel.
Claim 35
Dependent Claim 19 words
A process as in claim 22 including cooling said partially pyrolyzed solid phase after it exits the pyrolysis reactor.
Claim 36
Dependent Claim 31 words
A process as in claim 33 wherein cooling of the pyrolyzed solid phase to less than 300° Fahrenheit is accomplished by passing said solid phase in indirect heat exchange with water.
Claim 37
Dependent Claim 57 words
A process as in claim 31 including magnetically separating steel wire from the cooled, pyrolyzed solid phase; physically separating trash from the solid phase by passing the solid phase through a relatively coarse screen of between 4 and 10 mesh; discarding the trash; and recycling at least a portion of the pyrolyzed material to the reaction vessel.
Claim 38
Dependent Claim 24 words
A process as in claim 22 including compressing said gas and burning at least a portion of said compressed gas to supply process heat.
Claim 39
Dependent Claim 33 words
A process as in claim 22 wherein the amount of the first portion is between all and five percent of the amount of the partially pyrolyzed solid phase produced from the reaction vessel.

References Cited (Backward Citations)

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US3823224A Cited
US3966487A Cited
US3772242A Cited
US4098649A Cited
US3996022A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-08-17 1985-02-16 1985-08-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-08-17 1989-02-16 1989-08-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-08-17 1993-02-16 1993-08-18 $7700.00 Window Closed / Lapsed

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