1 US B2 (12) United States Patent (10) Patent No.: US 8,211,680 B2 Retsina et a. (45) Date of Patent: Ju. 3, 2012 (54) PROCESS FOR OBTANNG BOCHEMCALS 435/105; 530/500; 536/1.11; 536/30; 536/55.3; N A ZERO-LQUD DSCHARGE PLANT 536/ 56; 536/ 69 (58) Fied of Cassi?cation Search /165, (75) nventors: Theodora Retsina, Atanta, GA (US); Vesa Pykkanen,Atantas GA (Us); 435/163, 162, 161, 160, 140, 72, 100, 101, 435/105; 530/500; 536/1.11, 30, 55.3, 56, Kimberey Neson, Atanta, GA (US) 536/69 See appication?e for compete search history. (73) Assignee: AP nteectua Property Hodings, LLC Atanta G A (Us) (56) References Cited ( * ) Notice: Subject to any discaimer, the term of this U'S' PATENT DOCUMENTS (21) App.No.: 12/474,267 U'S'C' patent is 154(b)by extended 213 or days adjusted under / ; A1* 221: 10/2008 $883 Yang gersfr 00 yeta.,,,,,,,,,,,,,,,,...,,.. 435/ / A1 * 7/2009 Heikkia et a /55 OTHER PUBLCATONS (22) Fed: May Aden et a., Lignoceuosic biomass to ethano process design and (65) Prior Pubication D at a economics of utiizing co-current diute acid prehydroysis and enzy matc hydroysis of corn stover. Technica Report NREL/TP-S 10 US 2009/ A1 Dec. 10, ; 1-154,* AZate et a., Energy consumption anaysis of integrated?owsheets Reated US. Appication Data for production of fue ethano from ignoceuosic biomass. Energy, , vo. 31; * (60) PrOVsOna apphcanon NO 61/ ?ed on May Koppo et a., On Zero Water discharge soutions in the process indus 29, try. Adv. Environ. Res, 2003, vo. 8: * (51) nt, C, * cited by examiner C12P 7/10 C121) 7/0g ( ) (200601) Primary Examiner * Ganapathirama Raghu C12P 7/14 (200601) (74) Attorney, Agent, or Firm * Ryan P. O Connor C12P 7/06 C12P 7/16 ( ) ( ) (57) ABSTRACT C121) 7/ 54 ( ) A method is presented for the production of ceuosic etha C121) 1 9/ 00 ( ) 1101, acetic acid and derivatives from the extract containing C121) 19/12 ( )?bers and hemiceuoses after steam cooking of biomass in a C121) 1 9/ 04 ( ) host pant. The process is integrated With the host pant pro C121) 19/02 ( ) cess to minimize the effect of oss of heat vaue from the C0 7G 1/00 (201 1 ~01) extracted hemiceuoses and eiminate the need for the Waste C0 7H 1/ 00 ( ) Water treatment pant. (52) US. C /165; 435/163; 435/162; 435/161; 435/160; 435/140; 435/72; 435/100; 435/101; 17 Caims, 2 Drawing Sheets
2 US. Patent Ju. 3, 2012 Sheet US 8,211,680 B2 FOSSL FUEL DSPLACEMENT POWER 4 - _ _ _ _ _ 1 _. _... _. _. _. _. _. _... _. _. _. _... _.. _. _. HOUSE :AKEUP WATER -. _. _. _. _ ' :......!. T CAUSTC _ SODA.. ' BOARD EFF-UENT PRMARY UL TM F'LTER NANOF'LTER v _ REVERSE AcETATE PLANT : CLARFER ' TURBDTY > SUGAR 5M055 ' CRYSTALLZATON mpmuucr REMOVAL REMOVAL ACETATE SEPARATON z MQLAssEs DRY V M CRYSTALLZATON ORGANC - SULFURC A STREAM ACD i r ACD HYDROLYSS OF ORGANC STREAM A NOTE: HEX- HEAT EXCHANC ER SMULTANEOUS ETHANOL c5 AND C6 HEX _> E'HANOL! A FERMENTATON k DSTLLATON W! YEAST i PREPARATON L.._.."2T." TF....._i....._ Figure. A fow sheet exampe of the invention process. Process steps may be in other sequences.
3 US. Patent Ju. 3, 2012 Sheet 2 0f 2 US 8,211,680 B2 Concentration, mg/ml As Received After Hydroysis After Fermentation Acetic Acid HMF Furfura Ceubiose Gucose Mannose ND Gaactose Xyose Arabinose Tota Sugars Ethano N/A N/A Figure 2. A resuting acetic acid concentration and an exampe of hydroysis and fermentation of treatment of effuent from steam cooking of mixed hardwood chips.
4 1 PROCESS FOR OBTANNG BOCHEMCALS N A ZERO-LQUD DSCHARGE PLANT FELD OF THE NVENTON This invention reates, in genera, to the post treatment of e?uent from forest product or food or beverage pant. The treatment speci?cay converts the soube fraction of extracted ignoceuosic materia to byproduct ethano, ace tic acid and other chemicas. BREF DESCRPTON OF THE DRAWNGS A more compete understanding of the present invention may be obtained by reference to the foowing detaied description When read in conjunction With the accompanying drawings Wherein: FG. 1 iustrates a typica genera arrangement of the unit operations for mixed hardwood derived extract from steam cooking Water e?uent. Other e?uent iquors are possibe. FG. 2 shows concentrations of acetic acid and other Wood derived components after hydroysis and fermentation of treatment of e?uent from steam cooking of mixed hardwood chips. BACKGROUND OF THE NVENTON Forest products industry e?uents contain dissoved or mechanicay separated Wood components. The major Wood components are ignin, hemiceuoses and ceuose. The puping processes preferaby separate ignin and hemiceu oses. The dissoved ignin and hemiceuoses are burned for process energy and chemica recovery in the most puping processes. Some of the?bers and dissoved Wood compo nents escape the process to the e?uent treatment pant. The recovery, separation, and upgrade of the degraded hemice uoses into chemicas and derivatives are currenty not prac ticed. These hemiceuoses are most commony consumed during activated sudge WasteWater treatment. The activated sudge is then and?ed or bumed. Speci?cay, the steam cooking process dissoves predomi nanty hemiceuoses in temperatures above 160 degrees C. The soution containing hemiceuoses removed from this process is termed extract. The extraction of hemiceuoses using steam cooking and bowing through pressure reducing vave, commony termed bow vave, is used in the produc tion of medium and hard density board. Because of the ow concentration of hemiceuoses in the extract, When the hemiceuoses are hydroyzed to sugars, the subsequent con centration of sugars through evaporation before fermentation to produce ethano is energy intensive. Research indicates that ethano, acetic acid and their byproducts can be derived from the extract. Especiay, pre dominanty hardwood, containing bark, produces extract rich in acetic acid and sugars as taught by Amidon et a. in (US. Patent Appication No. 2007/ A1, Apr. 12, 2007). The present inventors have now deveoped a process Wherein the hemiceuoses in the extract can be converted to chemica products in an energy e?icient process. SUMMARY OF THE NVENTON The present invention describes a process for the produc tion of ethano, acetic acid and derivatives from hemiceuo ses extracted from steam expoded biomass. Treating the hemiceuoses extracted through a series of membranes, hydroysis, fermentation and distiation recovers saeabe US 8,211,680 B products. The process is integrated With the ho st pant to reuse Water and minimize process energy consumption and eimi nate the need for the Waste Water treatment pant. DETALED DESCRPTON OF THE NVENTON Biomass is heated in a batch or continuous digesting vesse With steam and bown through a vave commony termed bow vave. The bown chips are Washed With Water to recover the dissoved ignoceuosic components, termed extract, into the Wash?trate. For Wood chips biomass, the Wash?trate contains?bers, some dissoved ignins and hemiceuoses derivatives, i.e., xyan, gucan, mannan, arbi nan, gaactan, and acetic acid. The Wash?trate is at approxi matey 2% soids concentration at 50 degrees C. temperature is cari?ed and diverted to the membranes. The remaining biomass is sent to a board or puping process digester Where it is converted to?na product. The?rst step of the process is sedimentation. The Wash?trate is cari?ed from suspended materia, such as?ber and sand by cari?cation or centrifugation. From the sedimenta tion, the cari?ed?trate is then sent to the utra?tration step. The suspended soids are further concentrated in a?ter press to form combustibe product. At this point the cari?ed?trate may be acidi?ed to increase acetic acid yied and reduce microbia fouing of the membranes. The second step of the process is utra?tration of the arge moecues for ignin remova. The cari?ed?trate eaving the sedimentation is sent to a bank of utra?tration membrane eements. The utra?tration membrane reject arge dissoved moecues, such as ignin at moecuar Weight cutoff between MW:3,000 and MW:10,000. The concentrate from the utra?tration membrane is combined With the suspended so ids and combusted. The third step of the process is nano?tration for sugar moecue remova. The permeate from utra?tration is sent to a nano?tration membrane skid, Where the moecues over MWOO are concentrated. These moecues are predomi nanty Wood hemiceuoses and sugars. The sugars are sent to hydroysis, Whie the membrane permeate is sent to acetic acid separation. The fourth step is reverse osmosis?tration. To recover the acetic acid from the nano?tration permeate, reverse osmosis membranes are used in akaine environment to convert acetic acid to acetate form. The reverse osmosis membrane perme ate is cean Water, because of good rejection of other mo ecues in akaine conditions as demonstrated by Mukho padhyay (US. Pat. No. 6,537,456, Mar. 25, 2003). n another version of the process acetic acid is separated in an acetic environment. The concentrated acetate can be sod as ique?ed de-icing product or be further concentrated by evapora tion for sae as an acetate product. The?fth step of the process is acid hydroysis. Sufuric acid or enzymes can be used to hydroyze the sugar concen trate from the nano?tration membrane, Which is rich in sug ars and hemiceuoses, into hydroyzate containing ferment abe sugars. The hydroysis reactors Wi be operated to give a continuous How of hydroyzate going to the fermentation and separations sections of the pant. The reaction conditions for the acid hydroysis Wi be 30 to 120 minutes residence time at a temperature of 80 to 180 degrees C. The ph of the soution during hydroysis Wi be 0.1 to 4 ph. This ow ph Wi convert poymer hemiceuoses into monomer sugars. Time, temperature and ph must be optimized to maximize sugar yied Without converting monomer sugars further to furfura and 5-hydroxy-2 -methyfurfura, Which inhibit fermentation.
5 3 Aternativey, a mixture of ceuase and xyanase enzymes can be used to perform hydroysis. The sixth step of the process is fermentation of biomass derived sugars. Fermentation of the fermentabe sugars in the hydroyzate is performed in a muti-stage semi-continuous process With a micro-organism capabe of converting?ve and six carbon sugars into ethano and carbon dioxide. Acetic acid product or ammonium hydroxide is used for the ph adjust ment and nutrients. Additiona nutrients and yeast are added in a recircuation ine for the?rst fermentation stage. Carbon dioxide is removed from the fermenters and scrubbed With iquid for acoho recovery and odor contro. The product, commony termed beer, from the fermentation stage is sent to distiation in the ethano coumn. The seventh step of the process is distiation of ethano. The beer from the fermentation process is sent to a distiation coumn to separate the ethano from the residua sugars that Were not fermented. Ethano eaves as the overhead product from the distiation coumn and is recovered at approxi matey 50% concentration. The?na concentration of the ethano product is performed in a rectifying coumn and moecuar sieves to obtain over 99% ethano concentration. Aternativey, membranes are used for?na concentration. A ethano distiation coumns are designed for continuous operation. The distiation bottoms are evaporated to achieve a zero iquid discharge pant operation. ntegration of the biore?nery With the existing pant. Pro cess integration of the biore?nery With the existing pant site is very important as it improves both the capita as We as the operating cost of the proposed instaation. The Water from the reverse osmosis step is used for boier feedwater makeup or any other fresh Water use point. Water reuse aso decreases the heating needs of the host pant. n this process, activated sudge is not burned, causing a decrease in the steam produced in the existing pant biomass boier. HoWever, this steam oss is mitigated by the reduction in energy required by the Waste Water pant and the host pant Where ess Water heating is required due to the recyce of hot Water from the reverse osmosis step. Exampe 1 The ph of 125 ml of extract from the steam cooking of hardwood chips Was adjusted to 1 by adding 95% sufuric acid. The extract Was then hydroyzed at 120 degrees C. for 1 hour in an autocave. The ph of the hydroyzed iquor Was adjusted to 5.6 using ammonium hydroxide (30% ammonia). The iquor Was then combined With 3 g peptone and 1.5 g yeast extract nutrients. 15 g of this soution Was combined With 3 g yeast and inocuated at 30 degrees C. for 4 hours. The inocuated soution Was recombined With the origina and fermented at 35 degrees C. for 4 hours. FG. 2 shows the concentration of acetic acid, ethano, and other Wood derived components for the extract as received, after hydroysis, and after fermentation. The invention caimed is: 1. A process for producing fermentabe sugars and an aka ine acetate from a biomass-derived extract, said process comprising: (a) providing a iquid extract produced during steam or hot-water cooking of biomass, Wherein said iquid extract comprises hemiceuoses, acetic acid, dissoved ignin, and suspended soids; (b) carifying said iquid extract by sedimentation or cen trifugation for removing said suspended soids, to pro duce a cari?ed extract; US 8,211,680 B (c) introducing said cari?ed extract to an utra?tration unit for removing said dissoved ignin With a moecuar Weight cutoff range of 3,000 g/mo to 10,000 g/mo, to produce an utra?tration concentrate comprising said dissoved ignin and an utra?tration permeate compris ing said hemiceuoses and said acetic acid; (d) introducing said utra?tration permeate to a nano?tra tion unit for removing said hemiceuoses, to produce a nano?tration concentrate comprising said hemiceuo ses and a nano?tration permeate comprising said acetic acid; (e) combining said nano?tration permeate With an akaine additive for converting said acetic acid to an akaine acetate, to produce a reverse-osmosis feed stream com prising said akaine acetate; (f) introducing said reverse-osmosis feed stream to a reverse-osmosis membrane, to produce a reverse-osmo sis permeate comprising Water and a reverse-osmosis concentrate comprising said akaine acetate; and (g) introducing said nano?tration concentrate to a hydroysis reactor, to produce a hydroyzate comprising fermentabe sugars. 2. The process of caim 1, Wherein said cari?ed extract is acidi?ed prior to step (c). 3. The process of caim 1, Wherein said suspended soids are recovered as a combustion fue. 4. The process of caim 1, Wherein said dissoved ignin is recovered as a combustion fue. 5. The process of caim 1, Wherein said utra?tration con centrate is combined With said suspended soids to form a combustion fue mixture. 6. The process of caim 1, Wherein said nano?tration unit comprises a membrane With a moecuar-weight cutoff of 100 g/mo. 7. The process of caim 1, Wherein said akaine additive is sodium hydroxide. 8. The process of caim 1, Wherein said reverse-osmosis permeate consists essentiay of Water. 9. The process of caim 1, Wherein said reverse-osmosis permeate is used as boier feedwater. 10. The process of caim 1, Wherein said reverse-osmosis permeate is recyced for use in said steam or hot-water cook ing of biomass. 11. The process of caim 1, Wherein said hydroysis reactor is operated in the presence of sufuric acid at a ph seected from 0.1 to 4, a hydroysis temperature seected from 800 C. to 1800 C., and a hydroysis time seected from 30 minutes to 2 hours. 12. The process of caim 1, Wherein said hydroysis reactor is operated in the presence of a mixture of ceuase and xyanase enzymes. 13. The process of caim 1, said process further comprising fermentation of said fermentabe sugars to produce a fermen tation product. 14. The process of caim 13, Wherein said fermentation product is ethano. 15. The process of caim 13, Wherein said fermentation product is butano. 16. The process of caim 13, said process further compris ing distiation of said fermentation product, Wherein disti ation bottoms are recyced or evaporated rather than dis charged as iquid. 17. The process of caim 16, said process further compris ing recycing said reverse-osmosis permeate and recycing cooing Water used for cooing said hydroyzate, to achieve a zero-iquid-discharge process. * * * * *