Method and apparatus for pyrolysis of a biomass
View Patent ↗A method and apparatus for effective pyrolysis of a biomass utilizing rapid heat transfer from a solid heat carrier or catalyst. Particularly, various embodiments of the present invention provide methods and apparatuses which incorporate progressive temperature quenching and rapid disengagement of the heat carrier material and reaction product.
1. A process for biomass conversion comprising:
a) utilizing a riser reactor having a mixing zone, an intermediate zone located above said mixing zone, and an upper zone located above said intermediate zone;
b) charging a biomass feed and a heat carrier material to said mixing zone above the location where a lift gas is charged to said mixing zone, thereby forming a mixture;
c) converting said biomass feed in said mixture to thereby form a reaction mixture comprising said heat carrier material and a product stream comprising oxygenated hydrocarbons;
d) charging at least one quench stream to said riser reactor through at least one quench stream conduit connected in fluid flow communication with said riser reactor at a location within: i) said intermediate zone, ii) said upper zone, or iii) both said intermediate zone and said upper zone, thereby lowering the temperature of said reaction mixture; and
e) separating at least a portion of said product stream from said heat carrier material in a disengager which is connected in fluid flow communication with said upper zone of said riser reactor.
2. The process of claim 1 wherein the temperature of said reaction mixture produced in step c) is in the range of from about 300 C to about 600 C; and wherein the temperature of said reaction mixture is lowered by 25 to 400 C by said at least one quench stream in step d) so that the reaction mixture is at a quench temperature.
3. The process of claim 2 wherein said at least one quench stream in step d) is introduced at the interface between said mixing zone and said intermediate zone.
4. The process of claim 2 wherein the temperature of said reaction mixture is lowered to said quench temperature through the introduction of a plurality of said quench streams in both said intermediate zone and said upper zone.
5. The process of claim 4 wherein the temperature of said reaction mixture is lowered by about 20 to about 60 C by each of a first, second and third of said quench streams.
6. The process of claim 1 wherein the temperature of said reaction mixture produced in step c) is in the range of from about 450 C to about 575 C; and wherein the temperature of said reaction mixture is lowered by 50 to 200 C by said at least one quench stream in step d) so that the reaction mixture is at a quench temperature.
7. The process of claim 1 wherein said at least one quench stream comprise a fluid selected from the group consisting of water, steam, caustic solutions, hydrotreated organics liquids, recycle bio-oil, carbon monoxide, carbon dioxide, ethane, ethylene, propane, propylene, methanol and other alcohols, naphthas, gas oil, and combinations thereof.
8. The process of claim 7 wherein said water or said steam are from water produced in the conversion process.
9. The process of claim 8 wherein said quench stream comprises water or steam and also comprises dissolved organics.
10. The process of claim 1 wherein components of said quench stream react with organic components of said product stream to form stabilized organic compounds.
11. The process of claim 1 wherein the time between biomass feed conversion in step c) and said separation of said product stream from said heat carrier in step e) is less than about 2 second.
12. The process of claim 11 wherein the time between biomass feed conversion in step c) and said separation of said product stream from said heat carrier in step e) is less than about 1 second.
13. The process of claim 12 wherein said heat carrier material/reaction product disengager in step d) comprises a cyclone which is closely coupled to said riser reactor.
14. The process of claim 13 wherein the time between biomass feed conversion in step c) and said separation of said product stream from said heat carrier in step e) is less than 0.7 second.
15. The process of claim 1 wherein said heat carrier material comprises a material selected from the group consisting of an inorganic inert material, an inorganic catalyst, and combinations thereof and wherein said biomass feed comprises lignocellulose.