Pyrolysis method and pyrolysis device for producing pyrolysis gas and pyrolysis coke

Patent metadata

Field	Value
Publication number	US-2025043189-A1
Application number	US-202218719498-A
Country	US
Kind code	A1
Filing date	Dec 20, 2022
Priority date	Dec 20, 2021
Publication date	Feb 6, 2025
Grant date	—

Abstract

The invention relates to a method and a device for providing pyrolysis oil and pyrolysis gas.

First claim

1 . A pyrolysis process for production of pyrolysis gas and pyrolysis coke, comprising:
a) providing biomass with a water content of below 30% by weight in piece form, where the median particle diameter D 50 of the biomass in piece form is between 2.0 mm and 60 mm, determined to ASTM E112; b) providing a pyrolysis apparatus comprising:
i) a reactor space in an essentially vertical arrangement, where the reactor space is essentially cylindrical and/or essentially conical,
ii) a conveying unit for transporting the biomass in piece form from the bottom upward through the reactor space;
iii) a heating unit for the reactor space;
iv) a feed for a heating medium into the heating unit from the top and a drain for the heating medium, such that the heating medium is conducted in countercurrent based on the biomass;
v) an outlet for the pyrolysis gases in the upper region of the reactor space;
vi) a discharge unit for pyrolysis coke or a discharge unit for pyrolysis coke and separated dust particles;
c) feeding the biomass in piece form from the bottom upward through the reactor space, such that there is a bed within the reactor space; d) heating the biomass in piece form at a heating rate of 0.3 to 5 K/s; e) pyrolyzing the biomass in piece form essentially in the absence of oxygen at a temperature of 400 to 750° C. for 5 to 60 minutes; f) removing the pyrolysis gases from the reactor; h) removing the pyrolysis coke obtained; and i) removing the pyrolysis gas.

2 . The process as claimed in claim 1 , wherein the pyrolysis apparatus further comprises:
vii) a dedusting unit for the pyrolysis gases.

3 . The process as claimed in claim 1 , wherein step h) of the process further comprises the feeding of the pyrolysis gases into a dedusting unit.

4 . The process as claimed in claim 1 , wherein the process further comprises:
g) separating off and removing dust particles; where step h) further comprises the removing of the pyrolysis coke obtained together with the separated dust particles.

5 . The process as claimed in claim 1 , wherein the process further comprises:
i) providing pyrolysis oil by partial condensation of the pyrolysis gas removed.

6 . The process as claimed in claim 1 , wherein step e) consists of pyrolyzing the biomass in piece form essentially in the absence of oxygen at a temperature of 450 to 650° C., for 5 to 60 minutes.

7 . The process as claimed in claim 1 , wherein pyrolysis oil is obtained by partial condensation of the pyrolysis gas removed as a biphasic mixture of pyrolysis oil and water, and this biphasic mixture is separated.

8 . The process as claimed in claim 1 , wherein the dust particles are separated off by cyclone and/or hot gas filter.

9 . The process as claimed in claim 1 , wherein the pyrolysis coke is discharged under gravity.

10 . The process as claimed in claim 1 , wherein the separated dust particles are removed together with the pyrolysis coke.

11 . The process as claimed in claim 1 , wherein the feeding of the biomass in piece form from the bottom upward through the reactor space is effected with a conveying screw, preferably at 0.5 to 20 revolutions per minute.

12 . The process as claimed in claim 11 , wherein the screw pitch of the conveying screw decreases from the top downward.

13 . The process as claimed in claim 1 , wherein the pyrolysis gases are prepurified by the bed of biomass in piece form.

14 . The process as claimed in claim 1 , wherein the bed of biomass in the upper region of the reactor space has lower bulk density than in the lower region of the reactor space.

15 . The process as claimed in claim 1 , wherein the bed height in the reactor space is chosen so as to achieve a dwell time of the biomass within the reactor space at a temperature of 400 to 750° C., of 5 to 60 minutes.

16 . The process as claimed in claim 1 , wherein continuous mixing of the biomass in piece form is effected by means of the conveying unit for transport of the biomass in piece form from the bottom upward through the reactor space.

17 . The process as claimed in claim 16 , wherein the conveying unit is configured such that the bed of biomass is partly mixed from the top downward, preferably in that the bed of biomass can move vertically downward close to the shell surface, most preferably close to the shell surface and under gravity.

18 . The process as claimed in claim 1 , wherein hydrogen is obtained from the pyrolysis gas.

19 . The process as claimed in claim 18 , wherein water is additionally introduced.

20 . A pyrolysis apparatus comprising:
i) a reactor space in an essentially vertical arrangement, where the reactor space is essentially cylindrical and/or essentially conical, ii) a conveying unit suitable for transporting biomass in piece form from the bottom upward through the reactor space so as to provide a bed; iii) a heating unit for the reactor space; iv) a feed for a heating medium into the heating unit from the top and a drain for said heating medium, such that the heating medium is conducted in countercurrent based on the biomass; v) an outlet for the pyrolysis gases in the upper region of the reactor space; and vi) a discharge unit for pyrolysis coke.

21 . The pyrolysis apparatus as claimed in claim 20 , wherein the pyrolysis apparatus further comprises:
vii) a dedusting unit for the pyrolysis gases.

22 . The pyrolysis apparatus as claimed in claim 20 , comprising external heating, wherein preferably the outer concluding face of the reactor or the outer concluding face of the reactor and the conveying unit are heated.

23 . The pyrolysis apparatus as claimed in claim 20 , wherein the heating medium is fed in from the top.

24 . The pyrolysis apparatus as claimed in claim 20 , wherein the heating medium is gaseous or the heating medium is a liquid metal or a liquid metal alloy, or the heating medium is a liquid salt melt.

25 . (canceled)

Assignees

• Fraunhofer Ges Forschung

Inventors

• Artmann Michael
• Apfelbacher Andreas
• Daschner Robert

Classifications

• C10B47/44

  with conveyor-screws · CPC title

• C10B1/04

  Vertical retorts · CPC title

• C10K1/026

  by centrifugal forces (cyclones B04C) · CPC title

• C10K1/001

  working-up the condensates (recovering of NH3 and NH4 salts C01C1/00; working-up or purifying tars and tar-oils C10C1/00) · CPC title

• C10B7/10

  with conveyor-screws · CPC title