O
`
`12,) Umted States Patent
`Froderman et al.
`
`(10) Patent N0.:
`(45) Date of Patent:
`
`US 8,962,059 B1
`Feb. 24, 2015
`
`US008962059B1
`
`54) BIO-BASED OIL COMPOSITION AND
`
`3005/0155232 A1
`
`7/3005 5:ig%‘_=1k0V\’ ‘=1 31'
`
`75)
`
`73-
`=1
`
`_
`IHVGHIOISI Christopher 5- Froderman: AVOH, IN
`(US); William C. Hildebrand,
`IN<Us>
`_
`I
`_ S
`.
`0.1 C
`_
`A, V.
`A hhlgnw "l?"“’” .1
`'°‘“P“">” H‘-=
`lndianapolis, IN (US)
`
`”‘ ) Notice:
`
`Subject to any disclaimer, the term of this
`I
`.
`V
`V
`.
`V
`patent is extended or «'.l(.l]Llblt!(.l under 35
`
`U's'C' 15403) by 81 dayS'
`
`.
`21) Appl NO" 13/111301
`.
`.
`F11°d'
`
`9/2007 Scheimann el al.
`2007/0210007 /\1*
`2007/0238891 A1* 10/2007 VVinsness et al.
`2008/0110577 Al
`5/2008 Vi/insness
`._
`,_
`’
`.._
`a e
`%88§$8;%§31i:1
`sag:
`2009/0293344 A1
`12/2009 O’Brien et a1.
`2012/0245370 A1 *
`0/2012 Sheppard et al.
`()'1'l-IER l’UBLlCA1'l()N S
`
`.
`...... ..
`
`.. 210/728
`
`554/3
`
`554/204
`
`__
`_
`David G. Cooper. J.E. Zajic, Edward J. Can11el and Joan W. Wood.
`.“
`,,
`.
`.
`.
`.
`.
`.
`The Relevanceol HIB loDe-Emulsillcalion ol aMI.xlureol Heavy
`Oil, Water and Clay. The Canadian Journal ofChemical Engineering
`Vol. 58, Oct. 1980; pp. 576-579.”‘
`Hui Wang, Tong Wang, and Lawrence A. Johnson Effect of Low-
`Shear Extrusion on Corn Fermenmtion and Oil Partition. J. Agric.
`Food Chem. 2009, 57, 2302-2307*
`Singh, N. et al., "Extraction of Oil From Corn Distillers Dried Grai11s
`With Solubles,” Transactions oft/leASABE, Vol. 41, No. 6, Nov./Dec.
`1993. pp. 1775-1777.
`“The HLB Syste1nA lime-Saving Guide to Emulsilier Selection," ©
`1076 [C1 United States Inc, 22 pages.
`(Continued)
`
`Primary Examiner —l1umera Sheikh
`.4ssistar2t Examiner— Subbalakslimi Prakash
`(74) Anoriiefv, Agent, or Firm — William F. Bahret
`
`ABSTRACT
`(57)
`A method of extracting oil fron1 a byproduct stream of a
`bio-based ethanol production process and 21 organic co1npo-
`sitio11 resulting from the method is provided. The method
`includes applying an oil concentrator to a byproduct stream,
`mixing the oil concentrator with the byproduct stream, and
`separating the oil from the byproduct stream. An organic
`composition comprising oil derived from a byproduct stream
`of a bio-based ethanol production process and an oil concen-
`trator is also provided.
`
`16 Claims, 5 Drawing Sheets
`
`22)
`_
`51,)
`
`May 27‘ 2011
`
`(2006-01)
`(2006-01)
`
`‘
`Int‘ ('1'
`C1113 3/16
`C113 13/00
`52) U_S_ C]_
`USPC .......................... .. 426/601; 554/206; 426/623
`58) Field of Classification Search
`CFC
`~~~~~~~~ ~~ C113 1/103 C1 1B 13/00
`.
`ISISPC
`fil f""" 4261/6015 6231:1554/204° 206
`ee app Eamon
`e or comp ete Seam nstory
`References Cited
`U.S. l’A1'EN '1' DOCUMENTS
`
`(56)
`
`................. . 554/10
`
`8/1052 Darling etal.
`2,606,916 A *
`12/1953 Strezynski
`2,663,718 A
`4,702,798 A * 10/1987 Bonanno ................. .. 159/47.1
`5,250,182 A
`10/1993 Benlo et al.
`5,662,810 A
`9/1997 Willgohs
`5,795,477 A
`8/1998 Herman et al.
`6,433,146 B1
`8/2002 Cheryan
`7,601,858 B2
`10/2009 Cantrell et al.
`7,608,729 B2
`10/2009 Winsness et al.
`2003/0180415 A1
`9/2003 Sriefel etal.
`2004/0087808 A1
`5/2004 Prevostet al.
`
`bio-based
`source
`material
`
`whole stillage
`byproduct
`
`high solids
`without
`solubles
`
`stream liquid stillage
`solubles
`
`
`
`dried stillage
`with de—oi|ed
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`US 8,962,059 B]
`Page 2
`
`(56)
`
`References Cited
`OTHER PUBLICATIONS
`
`Becher, Paul, Emulsions." Theolfy (1ndPmm‘ice, Reinhold Publishing,
`New York, c. 1957, Chapter 6, “'lhe Chemistry of hrnulsifying
`Agents.” p. 209-265.
`Watkins, Catherine, “Two Fuels From One Kernel,” Infiirm, vol. 18,
`No. 11, Nov. 2007, pp. 714-718.
`lumisorb PSTS-20 K (Polysorbate 65) Technical Data Sheet, Lam-
`bent Technologies, c. 2006, 2 pages.
`
`Lumisorb PSMO-20 K (Polysorbate 80) Technical Data Sheet, Lam-
`bent Technologies, c. 2004, 2 pages.
`GreenShift Corporation Corn Oil Extraction Process Description,
`[online]. © 2005-2010. [retrieved Nov. 17. 2010]. Retrieved from the
`lnlernel: hllp://www.greenshill.com/cornoil.pl1p?mode:2, 2 pages.
`FDA Part I72, Code of Federal Regulations Title 21, Part 172,
`[online], undated,
`[retrieved Dec. 3, 2012]. Retrieved from the
`Internet: http://www.accessdatafda.gov/scripts/cdrh/efdoe s/cfCFR’
`CFRSearch.cfm?CFRPa1t:l72, 5 pages.
`
`* cited by examiner
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`U.S. Patent
`
`Feb. 24, 2015
`
`Sheet] of5
`
`US 8,962,059 B1
`
`bio—based
`
`whole stillage
`
`source
`
`material
`
`byproduct
`
`stream
`
`high solids
`
`without
`
`solubles
`
`
`
`liquid stillage
`
`dried stillage
`
`with de—oi|ed
`
`solubles
`
`FIG. 1
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`U.S. Patent
`
`Feb. 24, 2015
`
`Sheet 2 of5
`
`US 8,962,059 B1
`
`whole stillage
`
`byproduct
`stream
`
`high solids
`
`without
`
`solubles
`
`stillage with
`
`de—oi|ed
`
`solubles
`
`dried stillage
`
`with solubles
`
`FIG. 2
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`U.S. Patent
`
`Feb. 24, 2015
`
`Sheet 3 of5
`
`US 8,962,059 B1
`
`FIG. 3
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`U.S. Patent
`
`Feb. 24, 2015
`
`Sheet 4 of5
`
`US 8,962,059 B1
`
`whole stillage
`
`byproduct
`stream
`
`I‘
`i
`I
`
`I.
`
`apply oil
`concentrator
`
`high solids
`
`without
`
`solubles
`
`
`
`
`"I
`I
`: concentrate :
`I
`I
`E and separate E\)
`'
`OII
`I
`L _____________ __I
`1'
`
`stillage with
`de-°"ed
`
`solubles
`
`dried stillage
`
`with solubles
`
`FIG. 4
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`U.S. Patent
`
`Feb. 24, 2015
`
`Sheet 5 of5
`
`US 8,962,059 B1
`
`
`
` [IIIIIIIIIIIA Ida
`
`FIG. 5B
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`US 8,962,059 B1
`
`1
`BIO-BASED OII. COMPOSITION AND
`l\/IETIIOD FOR PRODUCING TIIE SAME
`
`BACKGROUND OF THF INVENTION
`
`This invention relates to a plant oil product and methods of
`producing the product from a bio-based ethanol byproduct
`stream, and more particularly to a com oil product and meth-
`ods of recovering the corn oil product from a dry milling
`process for obtaining ethanol from corn.
`The global production of ethanol fi‘om biologically based
`(bio-based) sources has recently expanded significantly.
`While the production of ethanol from petroleum sources
`remains, the ethanol supply is now primarily produced from
`renewable sources. The dry grind ethanol production process,
`using corn, is presently the primary source of ethanol in the
`United States. While the fermentation of sugars to produce
`alcohol is one of" hun1anity’s earliest and arguably most
`important discoveries, its implementation to mass producing
`ethanol for fuel has occurred relatively recently. The ethanol
`produced from corn is considered renewable because the
`growth of corn does not destroy the resources that it needs to
`produce compounds (e.g. starches and sugars) which can be
`treated enzymatically then fermented to produce ethanol.
`The manufacture of ethanol fror11 bio-based sources does
`not completely consume the bio-based material. Instead,
`there are typically considerable quantities of byproducts
`remaining after the fermentable sugars are converted into
`ethanol. Depending on the bio-based source, these byprod-
`ucts may be quite valuable. For example, the production of
`ethanol front corn using the dry mill production process
`results in a byproduct stream that is used primarily as an
`animal feed (dry distillers grains (DDG) or wet distillers grain
`(WDG)).
`Bio-based sources for the production of ethanol often
`include significant proportions of oils. For example, most
`crop plants contain some amount of oils. The oils in plants are
`primarily triglycerides. As such, they are 11ot fennentable and
`remain in the byproduct stream through the ethanol manufac-
`turing processes. Further, bio-based sources may be modified
`to increase the proportion of the source that is oil. For
`example, plant breeders began attempting to modify the oil
`content of corn ir1 studies that date back to the turn of the 20"’
`century. In the 1950s, it was possible to produce low oil corn
`having less than one percent oil by weight and high oil corn
`having greater than 15% oil. Currently, high oil corn hybrids
`are commercially available that contain up to about 8% oil.
`The value of" the oil is dependent upon the nature of the
`bio-based source. For example, peanut oil and olive oil may
`have substantial value as food products. However, many bio-
`based oils derive their value from their capacity to serve as a
`fuel; for example, bio—diesel is a transesterification product of
`triglycerides, primarily obtained from soy, which has become
`a significant fuel source. Oil from the byproduct stream ofthe
`bio-based production of ethanol may be a secondary product
`stream providing additional value to the overall process, so
`long as the co st ofobtaining the oil is below the value derived.
`Production facilities for bio-based ethanol generation have
`a clear focus on ethanol as the core product. However, the
`byproduct streams may provide an important and significant
`revenue stream that provides additional economic incentive
`for production growth. In particular, dried distillers grains
`with soluble (DDGS) has been the primary byproduct from
`these production facilities and its use as a feedstock for ani-
`mals l1as become important to the feed market. A production
`facility using corn as feedstock may produce almost 3 gallons
`ofethanol and almost 20 lbs. ofdistiller’s grains with solubles
`
`l0
`
`IS
`
`20
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`(dry basis) per bushel ofcorn. VVhile valuable, increasing the
`value of this byproduct stream enhances the overall value of
`the ethanol production process. One marmer of improving the
`value ofthe byproduct stream is the extraction ofoil from this
`stream for either food or fuel use.
`The DDGS byproduct stream is currently used as feed for
`animals; in particular, DDGS is feed for livestock such as
`ruminants. As such, the oil content has value as a component
`of the feed. The value of this byproduct has increased in
`response to the demand on the corn supply by ethanol pro-
`duction In particular, as greater proportions ofthe com sup-
`ply are used to produce ethanol,
`the price of corn l1as
`increased and the value of feed supplements, such as DDGS,
`has also risen. While DDGS is useful as a feed supplement, its
`inclusion at high levels does have a negative effect on the
`livestock. For example, dairy cows constuning high DDGS
`levels exhibit reduced milk fat production. High DDGS levels
`may also result in reduced conception rates. Increased soft fat
`in pork and bacon and reduced weight gain i11 beef feedlot
`cattle have also been observed. These negative effects are
`correlated to the high oil content of DDGS; thus, removal of
`oil from the byproduct stream increases the utility of the
`resulting DDGS product while also generating another valu-
`able byproduct stream, the oil.
`In one popular method of removing the oil from the
`byproduct stream, mechanical forces are used to separate the
`oil from thin stillage. Generally, this method recovers oil by
`recovering whole stillage from the process used for producing
`the ethanol and mechanically processing the whole stillage to
`provide distillers wet grains and thin stillage. The thin stillage
`is concentrated by evaporation and heated under pressure to
`effectuate separation. The thin stillage is then treated with
`high temperatures and pres sures prior to being separated into
`an aqueous phase and an oil phase through centrifugation.
`While this approach is effective. useful, and experiencing
`significant commercialization, there are disadvantages asso-
`ciated with this method. One disadvantage is that the use of
`elevated temperatures and pressures requires additional
`energy expenditure. This expenditure is accompanied by the
`concomitant financial and enviromnental expense. Further-
`more, extensive applications of heat and pressure may have
`deleterious effects or1 the remaining byproduct streams. For
`example, high temperatures and pressures may degrade (e.g.
`oxidize or hydrolyze) components ofthe thin stillage so that
`the resulting feed composition has a diminished value.
`Another limitation is that mechanical separation techniques
`have efficiencies directly related to the elevated temperatures,
`pressures, and mechanical force inputs. Thus, while inputting
`additional energy into the process generally increases yield,
`the retum on investment calculation dictates that the removal
`remains somewhat inefficient. /\s such, substantial oil is left
`within the byproduct streams to maximize the co st-benefit of
`the extraction.
`
`SUMMARY OF THE INVENTION
`
`One aspect of the present invention involves a method of
`extracting oil from a byproduct stream of a bio-based ethanol
`production process. An oil concentrator is applied to the
`byproduct stream ofthe bio -based ethanol production process
`ar1d mixed with the byproduct stream. The oil concentrator
`reduces interactions between the oil and oil sequestering
`components ofthe byproduct stream facilitating extraction of
`the oil from the byproduct stream.
`Another aspect ofthe present invention involves an organic
`composition including an oil derived from a byproduct stream
`of a bio-based ethanol production process a11d an oil concen-
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`US 8,962,059 Bl
`
`3
`trator. The oil concentrator includes a compound having a
`hydrophilic group and a lipophilic group. These groups pro-
`vide the oil cor1cer1trator a hydro pl1ile-lipo phile balance
`(HLB) of about 12 to about 18.
`Other aspects and advantages of the present invention will
`be apparent from the following descriptions with reference to
`the drawings.
`BRIEF DESCRIPTION OF THE DRAVVINGS
`
`FIG. 1 is a schematic showing byproduct streams gener-
`ated fror11 the production of ethanol from a bio—based source
`material;
`FIG. 2 is a schematic showing a method of extracting oil
`from the whole stillage byproduct stream from FIG. I, show-
`ing process steps in dashed boxes and byproduct streams in
`solid line boxes;
`FIG. 3 is a schematic showing the concentrate and separate
`oil step shown in FIG. 2 with exemplary additional detail;
`FIG. 4 is a schematic showing a second method of extract-
`ing oil from the whole stillage byproduct stream from FIG. I,
`wherein the oil concentrator is applied directly to the whole
`stillage byproduct stream; and
`FIG. 5(A—B) are schematics showing the layering of the
`aqueous layer, the rag layer, and the oil layer which occurs
`with (FIG. 5A) and without (FIG. SB) applying an oil con-
`centrator.
`
`DETAILED DESCRIPTION OF PREFERRED
`EMBODIMENTS
`
`For the purpose of promoting an understanding of the
`principles ofthe invention, reference will now be made to the
`embodiments illustrated in the drawings and specific lan-
`guage will be used to describe the same. It will nevertheless
`be rmderstood that no limitation ofthe scope of the invention
`is thereby intended, such alterations and further modifica-
`tions in the illustrated device and such further applications of
`the principles of the invention as illustrated therein being
`contemplated as would normally occur to one skilled in the art
`to which the invention relates.
`It is desired to increase the value ofbyproduct streams from
`the production of ethanol from bio—based sources. One man-
`ner of increasing the value is to separate the oil, which has
`greater value as a separate byproduct stream, from the stillage
`stream. Another manner of increasing the value of the
`byproduct stream is to separate the oil from the stillage stream
`according to a method that enhances, or maintains, the value
`of the remaining stillage byproduct stream.Yet another man-
`ner of increasing the Value of the byproduct streams is to
`enhance the efficiency by which the oil is separated from the
`byproduct stream. The use ofan oil concentrator on the whole
`stillage byproduct stream or a secondary byproduct stream
`derived therefrom provides a means for increasing the value
`of the byproduct streams. As described herein, application of
`an oil concentrator to the byproduct stream increases the
`overall value of the byproduct streams so that the production
`of ethanol from the bio—based source returns greater Value per
`quantity of source material used. In illustrative embodiments,
`a method of extracting oil from a byproduct stream of a
`bio—based ethanol production process comprises applying an
`oil concentrator to the byproduct stream of the bio—based
`ethanol production process, mixing the oil concentrator with
`the byproduct stream so that
`the oil concentrator reduces
`interactions between the oil and oil sequestering components
`of the byproduct stream, and separating the oil from the
`byproduct stream.
`
`l0
`
`I5
`
`20
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`4
`Referring to FIG. I, a bio—based source material can be
`used to produce ethanol through several well known tech-
`niques.
`'Ihe production of ethanol generates a byproduct
`stream that includes those non—fermentable components of
`the source material. For example, a dry milling method for
`producing ethanol uses the starch in corn to produce ethanol
`through fermentation and creates a byproduct stream com-
`monly referred to as “whole stillage.” As further shown in
`FIG. 1, the whole stillage byproduct stream may be further
`separated into a high solids byproduct stream and a liquid
`stillage byproduct stream. In the exemplary production of
`ethanol from com, this high solids byproduct stream is com-
`monly referred to as “distillers wet grains” and the liquid
`stillage byproduct stream is commonly referred to as “thin
`stillage." The liquid stillage, depending 011 the nature of tlie
`bio—based source material, may contain significant quantities
`ofvaluable oil. The oil byproduct stream has been historically
`considered part of the byproduct stream that is not harvested
`and passed through the distiller’s grain to produce animal
`feed products. The feed products are commonly distributed as
`distillers dried grains with soluble without a de-oiling step.
`However, as FIG. I shows, it is possible to separate oil from
`the byproduct stream while still passing the remaining
`solubles to the high solids byproduct stream to produce an
`animal feed product.
`FIG. 2 is a schematic showing a method of extracting oil
`from the whole stillage byproduct stream from FIG. 1. FIG. 2
`shows the process steps in dashed boxes and byproduct
`streams in solid line boxes. While there are various processes
`useful for the separation of the whole stillage byproduct
`stream from the liquid stillage byproduct stream, centrifuga-
`tion is commonly used. For example, a press/extruder, a
`screen centrifuge, a centrifugal decanter, a horizontal axis
`centrifuge, or a two—pl1ase helical conveyor centrifuge may be
`used to separate the whole stillage into a high solids byprod-
`uct (approximately 35% solids; e.g. distillers wet grains) and
`a liquid stillage (approximately 8% solids; e.g. thin stillage).
`Currently, the liquid stillage is either concentrated through an
`evaporation step to create syrup or de-oiled and concentrated
`to create de-oiled syrup. Either of these syrup byproduct
`streams ca11 be re-cornbined with the high solids byproduct
`stream and subsequently dried to produce animal feed. One
`a spect ofthe present invention is that the enhancement ofthe
`de-oiling process increases the amount of oil extracted from
`the liquid stillage stream while maintaining the value of tlie
`de-oiled syrup for addition to the high solids byproduct
`stream for drying.
`FIG. 3 shows illustrative process steps, according to one
`embodiment of the present invention, for processing syrup to
`produce de-oiled syrup and oil. While the prior art describes
`mechanical means for obtaining oil from a syrup, see for
`example U.S. Pat. No. 7,608,729, which is hereby incorpo-
`rated by reference in its entirety, the present process includes
`applying an oil concentrator to the syrup to facilitate separa-
`tion of the oil from the liquid. As shown in FIG. 3, according
`to one embodiment of the present invention, an oil concen-
`trator may be applied to a syrup that has been heated (e.g.
`between 100° F. and 212° F.) and pH adjusted (e.g. between a
`pH of 3 and 7). The composition can then be mixed in a
`baffled tank or other mixing unit for a time suflicient for the
`oil concentrator to act on the sequestered oil. The mixture
`then may be passed through a centrifuge, for example, a disk
`stack centrifuge, so that the oil can be separated from the
`syrup.
`Referring now to FIG. 4, shown is a schematic detailing
`that the oil concentrator may be applied directly to the whole
`stillage byproduct stream prior to the whole stillage being
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`US 8,962,059 B1
`
`5
`separated into a high solids byproduct stream and a liquid
`stillage stream. The remainder of the process remains as
`shown in FIG. 2. Similarly, as shown in FIG. 3, the “concen-
`trate and separate oil” step may or may not include a further
`addition of oil concentrator.
`While not limited to any particular theory, it is believed that
`the oil concentrator functions through several pathways to
`promote the enhanced recovery of oil from the bio-based
`ethanol production process byproduct streams. One aspect of
`the present invention is that depending on the bio—based
`source, it is common for byproduct streams to include oil
`sequestering components that emulsify and/or stabilize the
`oil within the liquid solution. For example, a syrup byproduct
`stream may include soluble starches, proteins, gums, and
`waxes that i11teract with the oil (primarily triglycerides) to
`prevent its separation from solution. The molecular structure
`of a triglyceride includes a glycerol backbone with three fatty
`acids groups bound through esterbonds. Each ofthe fatty acid
`groups of a particular triglyceride can be composed of a
`variety of fatty acids with different molecular weights and
`lipophilicity. The overall oil profile may include a relatively
`diverse range of triglycerides having a diverse range of fatty
`acids bound thereon. The result is a potentially broad distri-
`bution of lipophilicity amongst the population of triglycer-
`ides that makes up the oil profile of a given source. Further-
`more, the oil profile varies according to the source species,
`breed, and even with variable environmental and seasonal
`factors under which the source grew. The sequestering corn-
`ponents interact with the triglycerides to prevent the triglyc-
`erides from interacting with each other in a manner which
`would result in the formation of a distinct oil phase. Instead,
`the oil tends to remain dispersed in the aqueous phase stabi-
`lized by the starches. proteins. gums, and waxes.
`One aspect ofthe present invention is that it was discovered
`that an oil concentrator may be used to enhance oil recovery
`by interfering with the interaction between the naturally
`occurring oil sequestering components and the triglycerides
`so that the triglycerides are capable of interacting with each
`other so as to form a distinct oil phase. I11 illustrative embodi-
`ments, the oil concentrator comprises a surfactant compound
`having a hydrophilic group and a lipophilic group. The lipo-
`philic group may be selected to have a higher affinity for the
`fatty acid groups ofthe triglycerides than the naturally present
`oil sequestering component. Thus, the triglycerides separate
`from the oil sequestering component. As used herein, this
`effect is referred to as a “detergent effect.” Essentially, the
`detergent effect is a “washing” of the triglycerides from the
`starches, waxes, gums, and proteins that are included in the
`bio—based byproduct stream. The hydrophilic group provides
`solubility for the lipophilic group enabling aqueous solubil-
`ity.
`In addition to the detergent effect, the surfactant compound
`also acts in an interfacial capacity. In this capacity, the corn-
`potmd accumulates at the interface between the oil phase and
`the aqueous phase. As used herein, this effect will be referred
`to as the “interfacial effect.” The interfacial effect enables the
`formation ofoil droplets in an aqueous environment (i.e. an
`oil-in-water emulsion). One will appreciate that formation of
`an emulsion may be contradictory to the objective of separat-
`ing the oil from the aqueous dispersion. In particular, some
`emulsions, once formed, are stable and prevent the separation
`ofa11 oil and water mixture i11to discrete and separable phases.
`In fact, it was discovered that a number of compotmds known
`for their exemplary detergent properties frustrated the extrac-
`tion of oil from the byproduct streams. For suitability witl1ir1
`the present invention, an oil concentrator will include com-
`pounds that exhibit a suitable detergent effect and an appro-
`
`l0
`
`I5
`
`20
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
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`6
`priate interfacial effect. As described above, many byproduct
`streams include starches, waxes, gums, and proteins. Not only
`do these components interfere with the evaporators and
`reduce evaporative efiiciency, they reduce the efficiency by
`which high speed centrifuges are able to separate the oil from
`the liquid stillage. The presently described oil concentrator
`interacts with the oil, gums, and waxes to enhance separation
`of the oil from the stillage.
`It was discovered that the hydrophile—lipophile balance
`U-II B) ofa particular compound was a useful indicator for its
`eflicacy as an oil concentrator. Typically, HLB numbers are
`associated with nonionic compounds that have both hydro-
`philic components and lipophilic components. This type of
`compound is often called a surfactant, a tenn derived from the
`phrase “surface active agent,“ because the compounds con-
`centrate themselves and perform functions at surface inter-
`faces. Ilowever, as used herein, the term IILB is not limited to
`its application to nonionic surfactants alone. While HLB has
`a specific meaning for nonionic surfactants, its meaning can
`be extrapolated to other compounds useful within the scope of
`the present invention. As such, l-ILB may be considered as a
`general indicator of the hydrophilicity and lipophilicity of a
`given compound, regardless ofwhether it is ionic or nonionic.
`While the term surfactant is used herein, it is intended to
`encompass the general functional definition of the term and
`not to represent a certain class of compounds having a par-
`ticular structure. Compounds with a low HLB values are more
`lipophilic (lipid loving). These compounds may make water-
`in-oil emulsion (i.e. inverse-phase; e.g. hand cream) and have
`greater solubility in non-polar solvents (cg. oil) than high
`HIB compounds. I-ligh HIB value compounds are more
`hydrophilic (water loving) and tend to make oil-in-water
`emulsions (i.e. normal-phase; e.g. milk). These compounds
`tend to be more soluble in polar solvents (eg. Water).
`IILB values for a particular compound are determined by
`dividing the hydrophilic molecular weight percentage of tlie
`compound by 5. For example, if the compound has an average
`molecular weight of 1000 Daltons and the hydrophilic por-
`tion of that compound was 750 Daltons, the hydrophilic
`molecular weight percentage would be 75 andthe I-II B would
`be 15. Furthennore, each application has a particular HLB
`requirement. However. with respect to HLB values for certain
`applications, it should be noted that HLB requirements for
`most applications are calculated based on the concept that the
`end goal is a stabilized emulsion. That is, most HLB require-
`ment calculations and experiments establish the HLB for
`making a stable emulsion between a non-polar and polar
`sub stance. For example, the HLB requirement for corn oil in
`water has been determined to be 1 0. Thus, a surfactant having
`a HLB of 10 is likely to fonn a stable emulsion of corn oil in
`water. As described herein, the present invention does not rely
`on forming a stable emulsion; rather, the oil concentrator
`should provide stabilization and attraction to the oil enabling
`the oil to be withdrawn from the byproduct stream (detergent
`effect) while still forming an emulsion with marked instabil-
`ity so that the oil is easily separable fi‘on1 the aqueous phase.
`In illustrative embodiments, a method of extracting oil
`from the byproduct stream of the bio—based ethanol produc-
`tion process includes applying a11 oil concentrator comprising
`a surfactant compound having a hydrophilic group and a
`lipophilic group providing the oil concentrator a l1ydrophile—
`lipophile balance (HLB) of about 10 to about 19; preferably,
`from about 12 to about 18; more preferably, from about 14 to
`a bout 16; and even more preferably, around 15. A list of HLB
`values for various surfactants is available in many references
`such as the “The HLB System: a timesaving guide to emul-
`sifier selection” a publication of ICI United States, which is
`
`(cid:0)+(cid:0)<(cid:0)’(cid:0)5(cid:0),(cid:0)7(cid:0)((cid:0)(cid:3)(cid:0)((cid:0);(cid:0)+(cid:0),(cid:0)%(cid:0),(cid:0)7(cid:0)(cid:3)(cid:0)(cid:20)(cid:0)(cid:19)(cid:0)(cid:19)(cid:0)(cid:20)
`

`
`US 8,962,059 B1
`
`8
`compound. According to illustrative embodiments, a method
`of concentrating the oil from a bio-based production of etha-
`1101 includes using the oil derived from the bio-based source
`as a feedstock for the manufacturing ofadditional oil concen-
`rator, in a loop to extract additional oil. This process may
`include the addition of a reactive hydrophilic moiety that
`orovides the fatty acid ester derived from the triglyceride with
`an I-ILB value as described herein.
`Another aspect of the present invention is that both the oil
`and the de-oiled byproduct stream may be constuned by an
`animal (human or livestock). The oil concentrator, having
`Joth hydrophilic and lipophilic groups, will l1ave at least
`imited solubility i11 both the aqueous and the oil phases
`during a separation. As such, both the oil phase and the
`aqueous phase will include amotmts of the oil concentrator.
`In illustrative embodiments, an organic composition com-
`arising oil derived from a byproduct stream of a bio-based
`ethanol production process and an oil concentrator, the oil
`concentrator comprising a surfactant compound is described.
`r1 one embodiment, the organic composition comprises trig-
`ycerides. I11 another embodiment, the oil concentrator corn-
`orises a fatty acid ester of a sorbitol modified with a polyeth-
`ylene oxide. In another embodiment, the oil concentrator
`comprises about 1 ppm to about 10000 ppm of the organic
`composition; preferably, about 10 ppm to about 5000 ppm of
`he orgturic composition; more preferably, about 10 ppm to
`about I000 ppm of the organic composition; and even more
`oreferably, about 50 ppm to about 1000 ppm of the organic
`composition. 111 one embodiment.
`the oil concentrator is
`edible. In another embodiment, the food additive is usable in
`animal feed and drinking Water. As described above, both the
`aqueous and oil byproduct streams may be used for animal
`feed. As such, the oil concentrator used would ideally not
`impart an unsafe additive into either byproduct stream. As
`such,
`those compounds approved under FDA Part 172,
`describing food additives permitted for direct addition to food
`for human consumption, and FDA Part 573, food additives
`permitted in feed and drinking water of animals, are particu-
`larly preferred; both references are hereby incorporated by
`reference i11 their entirety.
`EXAMPLES
`
`Table 1 shows a number of commercially available surfac-
`tants tested to establish those properties that facilitate an
`understanding of the factors relating to the selection of a
`particular surfactant for use within the scope of the present
`invention.
`
`7
`hereby incorporated by reference in its entirety for disclosure
`related to IILB values. A mixture of surfac