Abstract: Energy efficiency is improved in a grain alcohol production plant (60) by capturing heat energy that otherwise would be lost to the environment when stillage evaporator last effect vapors (22) are condensed to recycle their water content. The low temperature/pressure heat energy of these vapors is efficiently recovered and reused by placing the vapors in direct physical contact (301, 402) with a working fluid (38) to form heated working fluid (54, 66), then using the heated working fluid directly in a process of the plant. In an embodiment, cook water used for the plant fermentation process is preheated by direct contact with stillage evaporator overhead vapor via one or more direct contact heat exchangers (301, 401) and/or a thermocompressor (402).

Abstract: A pyrolysis plant 20 comprises a grinding pyrolyzer 22, being a machine or apparatus in which both particle size reduction and pyrolysis occur simultaneously. Plant 20 also comprises a bin (hopper) 30 for holding wet particulate biomass feedstock. Chute 32 leads from the bin 30 to a biomass dryer 34 which reduces moisture content of the feedstock as low as possible, e.g., to below about 10. Dried feedstock is conveyed from dryer 34 via line 36 to a dried biomass feedstock hopper 38. Dried feedstock is fed from hopper 38 into a chute 40 which leads to an inlet trunnion 42 of grinding pyrolyzer 22. A discharge trunnion 44 of grinding pyrolyzer 22 leads to a char holder 60 for collecting char particles and a condensation train 62 for condensing vapor generated by the pyrolysis to produce oil.