Methods and systems for processing a reaction product mixture of cellulosic biomass material

A method comprising:

• providing a biomass feedstock containing cellulose and water;
• digesting at least a portion of the biomass feedstock to generate a digested product;
• separating the digested product into at least an overhead fraction and a bottom fraction, wherein the bottom fraction comprises (i) at least one compound having a separation point having a temperature in a range of about 100 to 600 degrees C. and a pressure of about atmospheric pressure selected, and (ii) one or more volatile organic compounds;
• vaporizing at least one volatile organic compound from the bottom fraction in a first flasher to generate an overhead product;
• depositing the at least one compound having a separation point having a temperature in a range of about 100 to 600 degrees C. and a pressure of about atmospheric pressure on a surface in the first flasher;
• placing the first flasher in standby mode;
• vaporizing at least one volatile organic compound from the bottom fraction in a second flasher to generate additional overhead product;
• and
• combusting the deposited at least one compound in the first flasher.

A system comprising:

• a digestion unit adapted to digest a cellulosic biomass material to generate a digested product;
• a separation zone adapted to separate the digested product into at least an overhead fraction and a bottom fraction;
• wherein the bottom fraction comprises (i) at least one compound having a separation point having a temperature in a range of about 100 to 600 degrees C. and a pressure of about atmospheric pressure, and (ii) one or more volatile organic compounds;
• and
• a recovery unit comprising:
• a flasher coupled to the separation zone to receive at least a portion of the bottom fraction;
• a first reboiler coupled to the flasher to provide the flasher with thermal energy during operation of the first reboiler;
• and
• a second reboiler coupled to the flasher to provide the flasher with thermal energy during operation of the second reboiler;
• wherein the recovery unit is configured to operate one of the first and second reboilers to provide thermal energy to the flasher to support operation of the flasher to vaporize at least one volatile organic compound in the bottom fraction while the other reboiler is in standby mode.

A method comprising:

• providing a biomass feedstock containing cellulose and water;
• digesting at least a portion of the biomass feedstock to generate a digested product;
• separating the digested product into at least an overhead fraction and a bottom fraction, wherein the bottom fraction comprises (i) a plurality of compounds having a separation point having a temperature in a range of about 100 to 600 degrees C. and a pressure of about atmospheric pressure selected, and (ii) one or more volatile organic compounds;
• vaporizing at least one volatile organic compound from the bottom fraction in a flasher to generate an overhead product;
• depositing at least a portion of plurality of compounds having a separation point having a temperature in a range of about 100 to 600 degrees C. and a pressure of about atmospheric pressure on a surface in a first reboiler coupled to the flasher;
• placing the first reboiler in standby mode;
• depositing at least another portion of plurality of compounds having a separation point having a temperature in a range of about 100 to 600 degrees C. and a pressure of about atmospheric pressure on a surface in a second reboiler coupled to the flasher;
• and
• combusting the deposited compounds in the first reboiler in standby mode to provide thermal energy to the flasher to support the vaporization in the flasher.