PROCESS AND PLANT FOR DISTILLATION OF METHANOL WITH HEAT RECUPERATION Russian patent published in 2017 - IPC B01D3/14 C07C29/80 

FIELD: chemistry.

SUBSTANCE: invention is intended for refining crude methanol. Method of refining crude methanol comprises at least three distillation stages operating in cascade at decreasing pressures, comprising at least a first distillation stage at a maximum distillation pressure (p2), a second distillation stage at a medium distillation pressure (p3), and a final distillation stage at a minimum distillation pressure (p4). First and second distillation stage each produce at least one respective gaseous stream of distilled methanol, and a respective solution containing methanol that is fed to next distillation stage. Final stage produces at least one gaseous stream of distilled methanol and a solution made up essentially of water. At least one first gaseous stream of distilled methanol, produced in first distillation stage, and a second gaseous stream of distilled methanol, produced in second distillation stage, are used as heat sources to heat up at least said second distillation stage and said final distillation stage, respectively. Plant for refining crude methanol includes at least three distillation columns operating in cascade at respective decreasing pressures. First column and second column each comprise at least one top outlet line for a gaseous stream of distilled methanol, and a bottom outlet line to feed a solution containing methanol to second column and to final distillation column, respectively. Top outlet lines of first column and of second column comprise a branch for directing at least one part of distilled methanol to heaters of second and third column respectively.

EFFECT: technical result is reduction of power consumption.

13 cl, 2 dwg, 2 tbl, 2 ex