Methods of and systems for producing biofuels

• US 8,152,870 B2
• Filed: 04/06/2011
• Issued: 04/10/2012
• Est. Priority Date: 04/06/2010
• Status: Expired due to Fees

• Current Assignee: Heliae Development, LLC (PT Perusahaan Perkebunan London Sumatra Indonesia Tbk)
• Original Assignee: Heliae Development, LLC (PT Perusahaan Perkebunan London Sumatra Indonesia Tbk)
• Inventors: Kale, Aniket
• Primary Examiner(s): Cutliff, Yate K
• Application Number:
  US13/081,232
• Publication Number:
  US 20110192075A1
• Time in Patent Office: 370 Days
• Field of Search: None
• US Class Current: 44/385
• CPC Class Codes: A61P 7/00 Drugs for disorders of the blood or the extracellular fluid
• CPC Class Codes: B01D 11/04 of solutions which are liquid
• CPC Class Codes: C11B 1/10 by extracting
• CPC Class Codes: C11B 1/108 after-treatment, e.g. of miscellae
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

A method for producing biofuels is provided. A method of making biofuels includes dewatering substantially intact algal cells to make an algal biomass, sequentially adding solvent sets to the algal biomass, and sequentially separating solid biomass fractions from liquid fractions to arrive at a liquid fraction comprising neutral lipids. The method also includes esterifying the neutral lipids, separating a water miscible fraction comprising glycerin from a water immiscible fraction comprising fuel esters, carotenoids, and omega-3 fatty acids. The method also includes obtaining a C16 or shorter fuel esters fraction, a C16 or longer fuel ester fraction, and a residue comprising carotenoids and omega-3 fatty acids. The method includes hydrogenating and deoxygenating at least one of (i) the C16 or shorter fuel esters to obtain a jet fuel blend stock and (ii) the C16 or longer fuel esters to obtain a diesel blend stock.

Claims

1. A method of making biofuels, comprising:

a. dewatering intact algal cells to make a wet algal biomass comprising intact algal cells;

b. combining the wet algal biomass with an amphiphilic solvent set, the solvent set comprising one or more amphiphilic solvents, to make a first extraction mixture, wherein the weight of the amphiphilic solvent set about the same as the weight of the wet algal biomass;

c. separating the first extraction mixture into a first liquid fraction comprising proteins and a first biomass fraction;

d. combining the first biomass fraction with an amphiphilic solvent set to make a second extraction mixture, wherein the weight of the amphiphilic solvent set about the same as the weight of the first biomass fraction;

e. separating the second extraction mixture into a second liquid fraction comprising polar lipids and a second biomass fraction;

f. combining the second biomass fraction with an amphiphilic solvent set to make a third extraction mixture, wherein the weight of the amphiphilic solvent set about the same as the weight of the second biomass fraction;

g. separating the third extraction mixture into a third liquid fraction comprising neutral lipids and a third biomass fraction, wherein the first liquid fraction has a higher protein concentration than the second and third liquid fractions, the second liquid fraction has a higher polar lipids concentration than the first and third liquid fractions, and the third liquid fraction has a higher neutral lipids concentration than the first and second liquid fractions;

h. transesterifying the neutral lipids to produce a mixture comprising glycerin, fuel esters and unesterifiable material;

i. separating a water miscible fraction comprising glycerin from a water immiscible fraction comprising fuel esters, and unesterifiable material;

j. recovering the fuel esters.

2. The method of claim 1 further comprising:

a. separating the fuel esters into a C16 or shorter fuel ester fraction, and a C16 or longer fuel ester fraction, by a separation technique selected from the group consisting of distillation, adsorption, or liquid-liquid extraction;

b. hydrogenating and deoxygenating the C16 or shorter fuel esters to obtain a jet fuel blend stock; and

c. isomerizing jet fuel blend stock to obtain jet fuel.

3. The method of claim 1 further comprising:

a. separating the fuel esters into a C16 or shorter fuel ester fraction, and a C16 or longer fuel ester fraction, by a separation technique selected from the group consisting of distillation, adsorption, or liquid-liquid extraction;

b. hydrogenating and deoxygenating the C16 or longer fuel esters to obtain a diesel blend stock; and

c. isomerizing diesel blend stock to obtain diesel fuel.

5. The method of claim 1, wherein the esterifying is catalyzed by an acid, a base or an enzyme.

6. The method of claim 1, wherein at least one of the solvent sets comprises an alcohol.

7. The method of claim 1, wherein at least one of the solvent sets comprises at least one of methanol, ethanol, isopropanol, acetone, ethyl acetate, and acetonitrile.

4. A method of making biofuels, comprising:

a. dewatering intact algal cells to make a wet algal biomass comprising intact algal cells;

b. combining the wet algal biomass with an amphiphilic solvent set, the solvent set comprising one or more amphiphilic solvents, to make a first extraction mixture, wherein the weight of the amphiphilic solvent set about the same as the weight of the wet algal biomass;

c. separating the first extraction mixture into a first liquid fraction comprising proteins and a first biomass fraction;

d. combining the first biomass fraction with an amphiphilic solvent set to make a second extraction mixture, wherein the weight of the amphiphilic solvent set about the same as the weight of the first biomass fraction;

e. separating the second extraction mixture into a second liquid fraction comprising polar lipids and a second biomass fraction;

f. combining the second biomass fraction with an amphiphilic solvent set to make a third extraction mixture, wherein the weight of the amphiphilic solvent set about the same as the weight of the second biomass fraction;

g. separating the third extraction mixture into a third liquid fraction comprising neutral lipids and a third biomass fraction, wherein the first liquid fraction has a higher protein concentration than the second and third liquid fractions, the second liquid fraction has a higher polar lipids concentration than the first and third liquid fractions, and the third liquid fraction has a higher neutral lipids concentration than the first and second liquid fractions;

h. esterifying the neutral lipids with a catalyst in the presence of an alcohol to make fatty acid esters and glycerin;

i. combining the fatty acid esters and glycerin with water;

j. separating a water soluble fraction comprising glycerin from a water insoluble fraction comprising fatty acid esters;

k. distilling the fatty acid esters to obtain a C16 or shorter fatty acid esters fraction, a C16 or longer fatty acid ester fraction; and

l. hydrogenating and deoxygenating at least one of (i) the C16 or shorter fatty acid esters to obtain a jet fuel blend stock and (ii) the C16 or longer fatty acid esters to obtain a diesel blend stock.

m. isomerizing at least one of (i) the jet fuel blend stock to obtain jet fuel and (ii) diesel blend stock to obtain diesel fuel.

8. A method of making biofuels, comprising:

a. dewatering intact algal cells to make a wet algal biomass comprising intact algal cells;

b. combining the wet algal biomass with an amphiphilic solvent set, comprised of one or more amphiphilic solvents, to make a first extraction mixture, wherein the weight of the first amphiphilic solvent set about the same as the weight of the wet algal biomass;

c. separating the first extraction mixture into a first liquid fraction comprising proteins and a first biomass fraction;

d. combining the first biomass fraction with an amphiphilic solvent set, comprised of one or more amphiphilic solvents, to make a second extraction mixture, wherein the weight of the second amphiphilic solvent set about the same as the weight of the first biomass fraction;

e. separating the second extraction mixture into a second liquid fraction, comprising carotenoids and polar lipids including phospholipids and glycolipids, and a second biomass fraction;

f. separating the second liquid fraction into carotenoids, phospholipids and glycolipids;

g. combining the second biomass fraction with an amphiphilic solvent set to make a third extraction mixture, wherein the weight of the amphiphilic solvent set about the same as the weight of the second biomass fraction;

h. separating the third extraction mixture into a third liquid fraction, comprising carotenoids and neutral lipids including omega-3 fatty acid rich oil, and a third biomass fraction, wherein the first liquid fraction has a higher protein concentration than the second and third liquid fractions, the second liquid fraction has a higher polar lipids concentration than the first and third liquid fractions, and the third liquid fraction has a higher neutral lipids concentration than the first and second liquid fractions;

i. separating the neutral lipids into carotenoids and omega-3 fatty acid rich oil

j. transesterifying the omega-3 fatty acid rich oil to produce a mixture comprising a water miscible fraction comprising glycerin and a water immiscible fraction comprising fatty acid esters;

k. separating the water miscible fraction comprising glycerin from the water immiscible fraction comprising fatty acid esters;

l. wherein the fatty acid esters comprise long chain omega-3 fatty acid esters and short chain fuel esters;

m. distilling the water immiscible fraction under vacuum to separate the long chain omega-3 fatty acid esters from the short chain fuel esters;

n. recovering the fuel esters.