Combined process for coal pyrolysis and char gasification

Patent · Tue Mar 25 04:00:00 EST 1986

OSTI ID:5759430

Gorin, E

This patent describes the method of converting coal to gaseous products. The method consists of: (a) admixing finely divided coal into a hydrogencontaining recycle gas stream, (b) providing a vertically elongated pyrolysis zone, (c) introducing the coal-containing recycle gas stream of step (a) into a lower region of the pyrolysis zone, (d) introducing a finely divided particulate heated char into a lower region of the pyrolysis zone, (e) passing the resulting mixture of heated char, finely divided coal, and recycle gas upwardly through the pyrolysis zone at a temperature between about 500/sup 0/ and about 950/sup 0/ C. and a pressure between about 3 and about 33 atmospheres absolute, (f) removing from an upper region of the pyrolysis zone a raw vapor stream comprising tar and lighter hydrocarbons, (g) separating condensible liquid products from the raw vapor stream of step (f) to produce a gas stream, (h) returning at least a portion of the gas stream from step (g) to comprise cycle gas of step (a), (i) removing from an upper region of the pyrolysis zone a stream of finely divided hot solids comprising char and ash, (j) providing a vertically elongated fluidized bed gasification zone, (k) passing the stream of hot solids from step (i) to an upper region of the gasification zone, (l) directing oxygen-containing gas and steam into a lower region of the gasification zone in amount sufficient to maintain the solids therein in a state of fluidization, (m) withdrawing from a lower region of the gasification zone a stream comprising coal ash, (n) withdrawing from an intermediate region of the gasification zone a stream comprising heated char, (o) passing the withdrawn char of step (n) to the step of introducing in step (d), and (p) withdrawing from an upper region of the gasification zone a synthesis gas product stream comprising carbon monoxide and hydrogen.

• Assignee: Conoco Inc., Wilmington, DE
• Patent Number(s): US 4578175
• OSTI ID: 5759430
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404 -- Coal
Lignite
& Peat-- Gasification
010406* -- Coal & Coal Products-- Pyrolysis & Cracking-- (-1987)
ASHES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHARS
CHEMICAL REACTIONS
COAL
COAL GASIFICATION
DECOMPOSITION
DISPERSIONS
ELEMENTS
ENERGY SOURCES
FLUID FLOW
FLUIDIZATION
FLUIDIZED BEDS
FLUIDS
FOSSIL FUELS
FUELS
GAS FLOW
GASES
GASIFICATION
HIGH PRESSURE
HIGH TEMPERATURE
HYDROGEN
MATERIALS
MEDIUM PRESSURE
MIXTURES
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PARTICLES
PARTICULATES
PYROLYSIS
PYROLYSIS PRODUCTS
RECYCLING
RESIDUES
THERMOCHEMICAL PROCESSES
VAPORS
VERY HIGH TEMPERATURE