US 8,499,702 B2 · Char-handling processes in a pyrolysis system

Abstract

Char-handling processes for controlling overall heat balance, ash accumulation, and afterburn in a reheater are provided. Carbonaceous biomass feedstock is pyrolyzed using a heat transfer medium forming pyrolysis products and a spent heat transfer medium. The spent heat transfer medium is separated into segregated char and char-depleted spent heat transfer medium. The char-depleted spent heat transfer medium is introduced into a dense bed of heat transfer medium fluidized by a stream of oxygen-containing regeneration gas. All or a portion of the segregated char is combusted in the dense bed using the stream of oxygen-containing regeneration gas. A portion of the segregated char may be exported out of the pyrolysis system to control the overall heat balance and ash accumulation.

Claims21

Dependent claims

A process for pyrolysis of a carbonaceous biomass feedstock in a pyrolysis system, comprising:

i) pyrolyzing carbonaceous biomass feedstock using a heat transfer medium forming pyrolysis products and a spent heat transfer medium;
ii) separating the spent heat transfer medium into segregated char and char-depleted spent heat transfer medium;
iii) introducing the char-depleted spent heat transfer medium into a dense bed of heat transfer medium fluidized by a stream of oxygen-containing regeneration gas;
iv) combusting all or a portion of the segregated char in the dense bed using the stream of oxygen-containing regeneration gas;
and
v) additionally combusting the segregated char outside of a reheater of the pyrolysis system in the stream of oxygen-containing regeneration gas before introduction of the segregated char into the dense bed.

3 more elements

Dependencies are inferred from the claim text.

Char-handling processes in a pyrolysis system

Life of this patent

Char-handling processes in a pyrolysis system

Life of this patent

Abstract

Claims21