Methods and devices for producing biodiesel, diesel-range hydrocarbons, and products obtained therefrom

A process for producing hydrocarbons from a biological feedstock comprising:

• a. subjecting the biological feedstock to a pre-treatment process comprising:
• i. heating the biological feedstock to a temperature above ambient temperature;
• ii. adding an aqueous acid solution to the heated biological feedstock and mixing to produce a mixture;
• and
• iii. separating the mixture to produce a refined biological feedstock;
• wherein the biological feedstock comprises a distillation bottoms recovered from a biodiesel distillation process, the distillation bottoms comprising unsaponifiable material at a concentration greater than 2 wt % and a fatty acid alkyl ester fraction comprising greater than 40 wt % C16 and shorter carbon fatty acid chains, and the refined biological feedstock has a reduced concentration of inorganic impurities and reduced alkalinity compared to the biological feedstock;
• b. diluting the refined biological feedstock with a hydrocarbon oil to produce a diluted biological feedstock,
• c. subjecting the diluted biological feedstock to a hydrodeoxygenation process comprising contacting the diluted biological feedstock with a hydrogen-rich gas and a catalyst at a temperature and pressure which are elevated above an ambient temperature and pressure to produce a reactor effluent;
• and
• d. recovering a hydrocarbons fraction from the reactor effluent.

A process for producing a purified biodiesel from a feedstock containing unsaponifiable material, said method comprising:

• a. introducing the feedstock to a first pre-treatment process to produce a pretreated feedstock;
• b. introducing the pretreated feedstock to a FFA refining process to produce a refined feedstock;
• c. reacting the refined feedstock in a transesterification reactor with an alcohol to produce a crude biodiesel;
• d. purifying the crude biodiesel by distillation to produce a purified biodiesel and a distillation bottoms having a concentration of inorganic impurities;
• e. subjecting the distillation bottoms to a second pre-treatment process comprising:
• i. heating the distillation bottoms to a temperature above ambient temperature;
• ii. adding an aqueous acid solution to the heated distillation bottoms and mixing to produce a mixture;
• and
• iii. separating the mixture to produce a refined biological feedstock;
• wherein the distillation bottoms comprise unsaponifiable material at a concentration greater than 2 wt %, and the refined biological feedstock has a reduced concentration of inorganic impurities and reduced alkalinity compared to the biological feedstock;
• f. diluting the refined biological feedstock with a hydrocarbon oil to produce a diluted biological feedstock;
• g. subjecting the diluted biological feedstock to a hydrodeoxygenation process by contacting the diluted biological feedstock with a hydrogen-rich gas and a catalyst at a temperature and pressure which are elevated above an ambient temperature and pressure to produce a reactor effluent;
• h. recovering a hydrocarbons fraction from the reactor effluent.

A process for producing stripped hydrocarbons from a biological feedstock comprising:

• a. subjecting the biological feedstock to a pre-treatment process comprising:
• i. heating the biological feedstock to a temperature above ambient temperature;
• ii. adding an aqueous acid solution to the heated biological feedstock and mixing to produce a mixture;
• and
• iii. separating the mixture to produce a refined biological feedstock;
• wherein the biological feedstock comprises a distillation bottoms recovered from a biodiesel distillation process, the distillation bottoms comprising unsaponifiable material at a concentration greater than 2 wt %, and the refined biological feedstock has a reduced concentration of inorganic impurities and reduced alkalinity compared to the biological feedstock;
• b. diluting the refined biological feedstock with a hydrocarbon oil to provide a diluted biological feedstock;
• c. subjecting the diluted biological feedstock to a hydrodeoxygenation process by contacting the diluted biological feedstock with a hydrogen-rich gas and a catalyst at a temperature and pressure which are elevated above an ambient temperature and pressure to produce a reactor effluent;
• d. separating the reactor effluent into a hydrocarbon phase, a gas phase, and an aqueous phase;
• e. using a hydrocarbon stripper to separate the hydrocarbon phase into a stripper overheads fraction and a stripped hydrocarbons fraction.