Iogen Energy Corporation

Vijay Anand

Jeffrey S Tolan

Brian Foody

Ziyad Rahme

Robert John Griffin

Colin Nicholson

Pat Foody

Corinne Mott

Stephen A Rowland

Daphne Wahnon

Patrick Foody, Sr

David Rea

Foody,pat

A process for recovering a volatile carboxylic acid from an aqueous stream containing same comprising the steps of: (a) evaporating the aqueous stream to produce a vapour stream comprising the volatile carboxylic acid that has been vapourized and water vapour, which aqueous stream is produced by a conversion process using a lignocellulosic feedstock as a substrate; (b) contacting the vapour stream with an organic solvent so as to extract the volatile carboxylic acid present in the vapour stream, thereby producing a liquid stream comprising the organic solvent and the volatile carboxylic acid, and a water vapour stream, wherein the organic solvent has an atmospheric boiling point of at least about 150&#xb0; C. and is insoluble in water; and (c) separating the volatile carboxylic acid from the organic solvent.

Recovery of volatile carboxylic acids by extractive evaporation

A process for recovering a volatile carboxylic acid from an aqueous stream comprising same, the process comprising the steps of: (i) steam stripping the carboxylic acid from the aqueous stream, which aqueous stream is produced by a conversion process using a lignocellulosic feedstock as a substrate, the steam stripping comprising contacting the aqueous stream with steam by flowing the aqueous stream and the steam countercurrent to one another, thereby producing a vapor stream comprising vaporized carboxylic acid and steam and a stripped aqueous stream; (ii) extracting the vaporized carboxylic acid with an organic solvent by contacting the vapor stream with the organic solvent to produce (a) a stream comprising the organic solvent and the carboxylic acid and (b) the steam at least substantially depleted of the carboxylic acid, wherein the organic solvent has an atmospheric boiling point of at least about 150&#xb0; C. and is insoluble in water; (iii) returning the steam from step (ii) to the steam stripping step (step i) to further strip the carboxylic acid from the aqueous stream; and (iv) separating the carboxylic acid from the organic solvent.

Recovery of volatile carboxylic acids by a stripper-extractor system

A method for recovering inorganic salt during processing of a lignocellulosic feedstock is provided. The method comprises pretreating the lignocellulosic feedstock by adding an acid to the feedstock to produce a pretreated lignocellulosic feedstock. A soluble base is then added to the pretreated lignocellulosic feedstock to adjust the pH and produce a neutralized feedstock. The neutralized feedstock is then enzymatically hydrolyzed to produce an enzyme hydrolyzed feedstock and a sugar stream. Inorganic salt is recovered from either a stream obtained from the lignocellulosic feedstock prior to the step of pretreating, a stream obtained from the pretreated lignocellulosic feedstock, a stream obtained from the neutralized feedstock, a stream obtained from the sugar stream, or a combination of these streams. The inorganic salt may be concentrated, clarified, recovered and purified by crystallization, electrodialysis drying, or agglomeration and granulation, and then used as desired, for example as a fertilizer.

Recovery of inorganic salt during processing of lignocellulosic feedstocks

A method is provided for hydrolyzing polysaccharides in a lignocellulosic feedstock to produce monosaccharides or pretreating a lignocellulosic feedstock, in which an aqueous slurry of the lignocellulosic feedstock is fed into a pressurized dewatering zone wherein the feedstock is partially dewatered and then is compressed into a plug. The plug is introduced into a reaction zone that operates at a pressure (P) equal to greater than about 90 psia and under suitable temperature and pH conditions to hydrolyze the polysaccharides or pretreat the feedstock. The plug provides a pressure seal between the outlet of the dewatering zone and the reaction zone. The pressure (P) of the aqueous slurry of the lignocellulosic feedstock at the inlet of the dewatering device is related to Pas follows:

Method for low water hydrolysis or pretreatment of polysaccharides in a lignocellulosic feedstock

A process for producing ethanol from a pretreated feedstock is provided. The feedstock is selected from grasses, cereal straws, stover, and combinations thereof, and least about 80% of the feedstock has a particle length of between about 2 cm and about 40 cm. This process comprises wetting the feedstock in liquid, pressing the wet feedstock through one roll press or a series of roll presses to remove at least a portion of water and soluble substances from the wetted feedstock and to shear the feedstock to produce feedstock particles of a size suitable for pumping at a solids concentration of about 8% to about 20% when slurried. At least one roll press, or at least one roll press in the series of roll presses comprises rolls with circumferential v-shaped grooves. The pressed feedstock particles are slurried to produce a slurried feedstock having a consistency of between about 8% and about 20%, and the slurried feedstock pumped into a pretreatment reactor. Dilute acid pretreatment of the slurried feedstock is carried out at a temperature of 160&#xb0; C. to 280&#xb0; C.

Process for producing a pretreated feestock

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&#xb0; C. to 280&#xb0; 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 is used to heat the feedstock slurry in the heating train.

Continuous flowing pre-treatment system with steam recovery

The present invention provides a method of producing xylose from lignocellulosic feedstock. The method comprises disrupting lignocellulosic feedstock; leaching the lignocellulosic feedstock by contacting the feedstock with at least one aqueous solution for a period greater than about 2 minutes to produce a leached feedstock and a leachate; removing the leachate from the leached feedstock; acidifying the leached feedstock to a pH between about 0.5 and about 3 to produce an acidified feedstock, and; reacting the acidified feedstock under conditions which disrupt fiber structure and hydrolyze a portion of hemicellulose and cellulose of the acidified feedstock, to produce a composition comprising xylose and a pretreated feedstock. The xylose may be purified from the pretreated feedstock or it may be converted to ethanol with the pretreated feedstock.

Method of processing lignocellulosic feedstock for enhanced xylose and ethanol production

A process for producing a pretreated feedstock is provided. The feedstock is selected from grasses, cereal straws, stover, and combinations thereof, and least about 80% of the feedstock has a particle length of between about 2 cm and about 40 cm. This process comprises wetting the feedstock in liquid, pressing the wet feedstock through one roll press or a series of roll presses to remove at least a portion of water and soluble substances from the wetted feedstock and to shear the feedstock to produce feedstock particles of a size suitable for pumping at a solids concentration of about 8% to about 20% when slurried. At least one roll press, or at least one roll press in the series of roll presses comprises rolls with circumferential v-shaped grooves. The pressed feedstock particles are slurried to produce a slurried feedstock having a consistency of between about 8% and about 20%, and the slurried feedstock pumped into a pretreatment reactor. Dilute acid pretreatment of the slurried feedstock is carried out at a temperature of 160&#xb0; C. to 280&#xb0; C.

Process for producing a pretreated feedstock

A method for recovering inorganic salt during processing of a lignocellulosic feedstock is provided. The method comprises pretreating the lignocellulosic feedstock by adding an acid or a base to the feedstock to produce a pretreated lignocellulosic feedstock. A soluble base or acid is then added to the pretreated lignocellulosic feedstock to adjust the pH and produce a neutralized feedstock. The neutralized feedstock is then hydrolyzed to produce an hydrolyzed feedstock and a sugar stream. Inorganic salt is recovered from a wash stream obtained from the pretreated lignocellulosic feedstock, a stream obtained from the neutralized feedstock, a stream obtained from the sugar stream, or a combination of these streams. The inorganic salt may be concentrated, clarified, recovered and purified by crystallization, electrodialysis, drying, or agglomeration and granulation, and then used as desired, for example, as a fertilizer.

Growing community of inventors

Brossard, Canada

Vijay Anand