High-grade ethanol production process

An ethanol production method comprising:

• a low boilers removal process including:
• receiving at a first distillation column at least one feed stream including ethanol, low boiling components having associated boiling points lower than a boiling point of ethanol, and high boiling components having associated boiling points higher than the boiling point of ethanol, wherein the high boiling components include water;
• forming a polynary mixture with a plurality of azeotropes split into separate distillation segments that are in fluid communication with one another within the first distillation column;
• removing a stream as an overhead stream from the first distillation column that includes at least a portion of the low boiling components and a first portion of the high boiling components;
• and
• a water removal process including:
• generating a vaporous stream from the at least one feed stream via the first distillation column;
• removing substantially all of the water from the vaporous stream via one or more membranes to produce an anhydrous stream including ethanol and high boiling components including water;
• and
• a high boilers removal process including:
• receiving the anhydrous stream;
• removing at least a portion of the high boiling components of the anhydrous stream from the anhydrous stream via a bottom stream of a second distillation column;
• and
• producing an overhead stream from the second distillation column, wherein the overhead stream consists of a high-grade ethanol product that comprises fewer impurities than fuel grade ethanol.

An ethanol production method comprising:

• a low boilers removal process including:
• receiving at a first distillation column, a first feed stream including ethanol, low boiling components having associated boiling points lower than a boiling point of ethanol, and, high boiling components having associated boiling points higher than the boiling point of ethanol, wherein the high boiling components include water;
• forming distillation zones in the first distillation column that each include a different polynary azeotrope of the low boiling components that are in fluid communication with at least one other polynary azeotrope in the first distillation column;
• removing a stream within one distillation zone as an overhead stream from the first distillation column that includes at least a portion of the low boiling components and a first portion of the high boiling components;
• and
• producing a first bottom stream from the first distillation column;
• a water removal process including:
• receiving a second feed stream, the second feed stream including at least a portion of the first bottom stream;
• and
• removing at least a portion of the water from the second feed stream to produce a dehydrated stream;
• and
• a high boilers removal process including:
• receiving in a second distillation column, a third feed stream including ethanol and high boiling components including a second portion of the high boiling components and water, the third feed stream being at least a portion of the dehydrated stream;
• removing at least a portion of the high boiling components of the third feed stream from the third feed stream via a bottom stream of the second distillation column;
• and
• producing an overhead stream from the second distillation column, wherein the overhead stream of the second distillation column consists of a high-grade ethanol product that comprises fewer impurities than fuel grade ethanol.