Cook water preheat using evaporator vapor heat recovery

A system for a grain alcohol plant, the system comprising:

• a non-contact condenser for transferring heat to the environment from a last effect vapor produced by an evaporator;
• a means for placing the last effect vapor into direct physical contact with a working fluid upstream of the non-contact condenser to at least partially condense the last effect vapor and to produce a heated working fluid;
• and
• a means for using the heated working fluid in a process of the grain alcohol plant,
• wherein the means for placing the last effect vapor into direct physical contact with a working fluid comprises one of a group consisting of a direct contact condenser and a thermocompressor.

A method of energy management in a grain alcohol plant, the plant including an evaporator operative to remove moisture from thin stillage and a cook water system operative to provide cook water, the method comprising:

• transferring heat from an overhead vapor produced by the evaporator to the cook water by:
• directing at least a first portion of the overhead vapor to a vapor inlet of a direct contact heat exchanger;
• and
• directing the cook water to a cook water inlet of the direct contact heat exchanger to produce warmed cook water,
• wherein the direct contact heat exchanger comprises a first direct contact heat exchanger, and further comprising:
• directing a second portion of the overhead vapor to a suction side of a thermocompressor and directing a plant process vapor to a motive side of the thermocompressor to produce a vapor mixture;
• and
• directing the vapor mixture to a vapor inlet of a second direct contact heat exchanger and directing the warmed cook water to a cook water inlet of the second direct contact heat exchanger to produce a warmer cook water.