Process for co-gasification of two or more carbonaceous feedstocks and apparatus thereof

• US 10,174,265 B2
• Filed: 12/29/2011
• Issued: 01/08/2019
• Est. Priority Date: 06/10/2011
• Status: Active Grant

• Current Assignee: Bharat Petroleum Corporation Limited (Government of India)
• Original Assignee: Bharat Petroleum Corporation Limited (Government of India)
• Inventors: Rakshit, Pranab Kumar, Voolapalli, Ravi Kumar, Maity, Pintu
• Primary Examiner(s): Akram, Imran
• Application Number:
  US14/119,615
• Publication Number:
  US 20140090298A1
• Time in Patent Office: 2,567 Days
• CPC Class Codes: C10J 2300/0913 Carbonaceous raw material
• CPC Class Codes: C10J 2300/0916 Biomass
• CPC Class Codes: C10J 2300/093 Coal
• CPC Class Codes: C10J 2300/0943 Coke
• CPC Class Codes: C10J 2300/0969 Carbon dioxide
• CPC Class Codes: C10J 2300/0976 as steam
• CPC Class Codes: C10J 2300/1215 using synthesis gas as fuel
• CPC Class Codes: C10J 2300/1253 by injecting hot gas
• CPC Class Codes: C10J 3/14 using gaseous heat-carriers
• CPC Class Codes: C10J 3/66 by introducing them into the gasification zone
• CPC Class Codes: C10J 3/721 Multistage gasification, e.g. plural parallel or serial gasification stages
• CPC Class Codes: F23G 2202/00 Combustion
• CPC Class Codes: F23G 2203/501 with external recirculation of entrained bed material
• CPC Class Codes: F23G 2203/503 with two or more fluidised beds
• CPC Class Codes: F23G 2900/50001 Combination of two or more furnaces
• CPC Class Codes: F23G 5/027 pyrolising or gasifying stage pyrolisation of sludge C02F11/00; destructive distillation of carbonaceous materials C10B53/00
• CPC Class Codes: F23G 5/30 having a fluidised bed
• CPC Class Codes: Y02P 20/145 the feedstock being materials of biological origin

Abstract

The present invention relates to a process for co-gasification of two or more carbonaceous feedstock, said process comprising combusting a first carbonaceous feedstock having high calorific value with low ash and high hydrogen content, to produce a heated effluent; carrying the heated effluent to second reactor where the heated effluent reacts with a second carbonaceous feedstock, having low calorific value with high ash and low hydrogen content, to produce synthesis gas. The present invention also relates to an apparatus for co-gasification of two or more carbonaceous feedstock, comprising a first reactor (3), having a first feedstock inlet port (1), a oxygen or air inlet port (2), a steam inlet port (9), a ash removal port (7), and a solid recycle port (6); a first cyclone separator (5) connected to the first reactor (3) through a first cyclone separator inlet port (4); a second reactor (16), having a second feedstock inlet port (10), and a ash removal port (15), the second reactor is connected to the first cyclone separator (5) through a gaseous inlet port (8); and a second cyclone separator (12), having a fine particles removal port (13), and an effluent port (14), wherein the second cyclone separator is connected to the second reactor through a second cyclone separator inlet port (11).

Claims

1. A process for co-gasification of two or more carbonaceous feedstock, said process comprising:

completely combusting a first carbonaceous feedstock having high calorific value with low ash and high hydrogen content, in presence of steam, with an amount of oxygen to produce a heated effluent in a first reactor;

separating carbon particles from the heated effluent using a cyclone separator as the heated effluent travels from the first reactor to a second reactor, wherein the cyclone separator is connected to the first reactor via a cyclone separator inlet port and the second reactor is connected to the cyclone separator via a gaseous inlet port, and recycling the separated carbon particles to the first reactor; and

carrying the heated effluent forward to the second reactor,

wherein the heated effluent reacts with a second carbonaceous feedstock, having low calorific value with high ash and low hydrogen content, in the second reactor to produce synthesis gas; and

wherein the first reactor and second reactor are separate vessels.

2. The process as claimed in claim 1, wherein

the step of completely combusting the first carbonaceous feedstock occurs in the first reactor selected from a fluid bed reactor or an entrained bed reactor, at a temperature in the range of 800 degrees C. to 2000 degrees C. and pressure in the range of 1 bar to 100 bar in presence of steam with an amount of oxygen to produce the heated effluent.

3. The process as claimed in claim 2, wherein the second reactor is selected from a moving bed reactor or a fluid bed reactor.

4. The process as claimed in claim 3, wherein the heated effluent is introduced radially into the moving bed reactor.

5. The process as claimed in claim 3, wherein the moving bed reactor is selected from up-draft moving bed reactor, or down-draft moving bed reactor.

6. The process as claimed in claim 1, wherein the first carbonaceous feedstock having high calorific value with low ash and high hydrogen content is selected from the group consisting of Petcoke, low ash Coal, Natural gas, Liquefied petroleum gas, synthesis gas, coal and oil emulsions or mixtures thereof.

7. The process as claimed in claim 1, wherein the second carbonaceous feedstock having low calorific value with high ash and low hydrogen content is selected from the group consisting of Indian Coal, high ash coal and Biomass or mixtures thereof.

8. The process as claimed in claim 1, wherein the amount of oxygen used in the combustion of first carbonaceous feedstock having high calorific value with low ash and high hydrogen content, is stoichiometric oxygen or ±

5 to ±

20% by weight than the stoichiometric oxygen.

9. The process as claimed in claim 1, wherein the oxygen is preheated at a temperature in the range of 200 degrees C. to 400 degrees C.

10. The process as claimed in claim 1, wherein the combustion of first carbonaceous feedstock having high calorific value with low ash and high hydrogen content is carried out at a temperature in the range of 900 degrees C. to 1800 degrees C.

11. The process as claimed in claim 1, wherein the combustion of first carbonaceous feedstock having high calorific value with low ash and high hydrogen content is carried out at a pressure in the range of 1 bar to 90 bar.

12. The process as claimed in claim 1, wherein the heated effluent comprises heat, super heated steam and hot gases.