Patent EA-004080-B1 (EA)
Title: Process for pre-hydrolysis of biomass
Inventor: GARCIA PINATTI DALTRO
IPC: C13B10/14
Filed: 2000-06-23
Abstract: 1. A biomass pre-hydrolysis process comprising the following steps: a) discharging of the biomass into the helical feeder for processing; b) flooding the biomass with an acidic solution; c) heating the mixture of the acidic solution and the biomass; characterized in that the biomass is compacted in the reactor and amount of the acidic solution being fed is such that liquid/solid ratio is adjusted to 2; the biomass is heated to a state which mainly corresponds to pulping hemi-cellulose and amorphous cellulose of said biomass. 2. The process according to claim 1, characterized in that the biomass is cut and washed in any sequence. 3. The process according to claim 1, characterized in that the biomass is fed with a helical feeder. 4. The process according to claim 1 or 3, characterized in that the biomass is fed into the biomass pre-hydrolysis device as far as the start of compaction, so as to achieve a density around 300kg/m<3>. 5. The process according to claim 1, characterized in that the biomass is flooded in the biomass pre-hydrolysis device with acidic solution, the amount of acid corresponding to 1.7% of the dry biomass, pH solution is about 1. 6. The process according to claim 1, characterized in that the acidic solution is pre-heated to about 80 degree prior to adding to the pre-hydrolysis device. 7. The process according to claim 1, characterized in that liquid/solid ratio has a temperature between about 150 and 170 degree C, preferably 160 degree C, and pressurization of about 0.62 MPa. 8. The process according to any one of claims 1 or 7, characterized in that if live steam is used for heating it is taken from the pre-hydrolysis device to maintain the temperature between about 150 and 170 degree C. 9. The process according to any one of claims 1, 7 or 8, characterized in that the escape steam is about 160 degree C. 10. The process according to any one of claims 1, 7, 8 or 9, characterized in that the heat of the escape steam is recovered in the heat exchanger pre-heating the acidic solution of the following reaction. 11. The process according to any one of claims 1, 7, 8, 9 or 10, characterized in that comprises a step of degasing in the initial phase of heating. 12. The process according to any one of claims 1, 7, 8, 9, 10 or 11, characterized in that the pre-hydrolysis is effected during about 30 minutes. 13. The process according to any one of claims 1, 7, 8, 9, 10, 11 or 12, characterized in that the pre-hydrolysis device is carried out with rotary oscillation. 14. The process according to claim 1, characterized in that the sugar content concentration is up to a value close to 10 Bricks. 15. The process according to claim 1 or 14, characterized in that the main component of the pre-hydrolysis is xylite, produced by hemi-cellulose pulping. 16. The process according to claim 1, characterized in that solid material is produced at a final step comprising crystalline cellulose and lignine, termed cellulignin. 17. The process according to claim 1 or 16, characterized in that sugar is recovered from the cellulignin followed the steps of: a) feeding filtered water in about 1 liquid/solid ratio; b) agitating in the pre-hydrolysis device; c) discharging the solution produced at previous steps. 18. The process according to claim 1, 16 or 17, characterized in that a step of cellulignin washing is carried out, the washing comprises the steps of: a) feeding filtered water in about 3 liquid/solid ratio; b) agitating in the pre-hydrolysis device; c) discharging the solution produced at previous steps. 19. The process according to claim 1 or 16, characterized in that comprises a step of discharging produced cellulignin. 20. The process according to claim 1, 16 or 19, characterized in that comprises a step of cellulignin washing from the pre-hydrolysis device. 21. The process according to claim 1 or 20, characterized in that external cellulignin washing is carried out by percolation on corresponding washers or carts. 22. The process according to claim 1 or 20, characterized in that external cellulignin washing is carried in mechanical washing facilities like facilities used for ore dressing. 23. The process according to claim 1, characterized by the use of filtered water in the process for producing normal cellulignin and deionized water in the process for producing clean cellulignin.