Continuous flowing pre-treatment system with steam recovery
US8017820B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 2005 |
| Grant date | Sep 13, 2011 |
| Priority date | — |
| Expiry date | Oct 28, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E50/10
- WIPO fieldBiotechnology
- WIPO sectorChemistry
Abstract
The present invention is directed to a continuous process for pretreating a lignocellulosic feedstock. A feedstock slurry is provided, which has a solids concentration of 10% to 33% by weight. The feedstock slurry is pumped through a heating train of at least two stages, each stage including a pump to increase stage pressure and a direct steam injection to heat the feedstock slurry. Acid is also added to the feedstock slurry prior to the heating train, during a heating stage, or after leaving the heating train; the acid is added at a concentration of 0% to 12% weight of acid on weight of initial feedstock. A heated, acidified feedstock slurry is thus produced. The heated, acidified feedstock slurry is flowed through a pre-treatment reactor at a temperature of 160° C. to 280° C. for a time sufficient to increase efficiency of conversion of cellulose in the feedstock to glucose using cellulase enzymes. After the slurry exits the pre-treatment reactor, it is cooled using two, or more than two flashing stages at successively lower pressures, without intermittent increases in pressure. The steam energy, at or near its flash temperature, from two or more than two of the flashing stages i…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.