NOVELTY - Hydrated biomass produced from ethanol process is dried by mixing hydrated biomass with solvent. The biomass is dehydrated and milled to change biomass into dry distillers grains with solubles (DDGS). Source of gaseous compound is introduced within feedback loop system associated with biomass drying. Filtrate is distilled to separate solvent and water. A negative pressure is created within the feedback loop system to move solvent vapors from the mixing, dehydrating, milling and distilling steps to condensing step and to draw off the gaseous compound and other vapors and air emissions.    USE - For drying hydrated biomass produced from an ethanol process to use as a food useful for human or animal consumption (claimed).    ADVANTAGE - The process is maintained at a lower temperature to maintain the food quality of the by-product DDGS and reduces the loading of volatile gas emissions subject to regulation. The drying process of a hydrated organic substrate is conducted in an environment of inert and stable atmosphere, maintaining a non-explosive atmosphere during the drying process because of the vacuum or negative pressure is pulled on the feedback loop system allowing the lower temperatures during the final drying process. The drying process or system is conducted in the feedback loop system at a negative pressure, with limited gas flow, recirculating and reclaiming gases in the process and thus minimizing air emissions.    DETAILED DESCRIPTION - Drying hydrated biomass produced from an ethanol process involves mixing the hydrated biomass with predetermined amount of organic solvent to create a water-solvent mixture within the biomass. The biomass is dehydrated to predetermined moisture content by removing the water-solvent mixture as a filtrate from the biomass. The dehydrated biomass is milled to expose its substrate particles to a dry, heated gas to change the biomass into dry distillers grains with solubles (DDGS) at a predetermined moisture content of less than or equal to 14. A source of stable, gaseous compound is introduced into the mixing and milling steps and into other various points within a feedback loop system associated with the drying of the biomass to create a non-volatile atmosphere for processing the biomass. The filtrate is distilled to separate the solvent from the water by evaporation in a stratified temperature atmosphere to draw off the solvent as a vapor for reclamation and to remove the water by discharging it. The reclaimed solvent vapor is condensed and the solvent is returned for reuse again in the feedback loop system. A negative pressure is created within the feedback loop system to move the solvent vapors from the mixing, dehydrating, milling and distilling steps to the condensing step and to draw off the stable gaseous compound and other vapors and air emissions vented from the mixing, dehydrating and milling steps to the condensing step for reuse of the stable, gaseous compound and for discharge or further processing of the other non-condensable gases and air emissions.    INDEPENDENT CLAIMS are included for:    (1) apparatus for dehydrating an organic substrate created as a by-product in ethanol production to provide a dry, free-flowing end product having properties enabling its use as a food for humans or animals, comprising a feedback loop system for processing the gases within the dehydration processing of the organic substrate, a mixing vessel for mixing a hydrated organic substrate with an organic solvent to form a water-solvent mixture, a source for introducing the organic solvent into the mixing vessel, a source of the hydrated organic substrate for introducing the hydrated organic substrate into the mixing vessel, a dehydration vessel using mechanical force to partially remove the water-solvent mixture from the hydrated organic substrate as filtrate for further processing, a mill agitating and passing a heated gas over the partially dehydrated organic substrate to further remove any remaining organic solvent as a vapor and to dry the dehydrated organic substrate to a predetermined level of moisture by weight of the organic substrate in its transformation to a dry distillers grains with solubles, a source of carbon dioxide (CO2) connected to the mixing vessel and to the mill to create a non-volatile atmosphere during respective dewatering in the mixing vessel and final drying of the organic substrate in the milling vessel, a distillation tower for separating the water-solvent filtrate into solvent vapors and water, and a negative pressure applied throughout the feedback loop system to assist the flow of reclaimed gases while moving other non-condensable gases for discharge from the system or further processing or treatment while creating lower operating temperatures during the final drying process, in which the organic substrate stays less than or equal to 200degreesF for drying the organic substrate in a non-volatile atmosphere and the quality of the DDGS end product is less degraded in flavor, color and uniformity; and    (2) hydrated organic substrate drying system comprising mixing device for mixing the hydrated organic substrate with a low molecular weight organic solvent, a mechanical device connected to the mixing device to partially remove the water-solvent mixture from the hydrated organic substrate, a heated milling device connected to the mechanical device, and the feedback loop system for gases within the drying system connected to the devices for introducing and venting gases from the mixing, mechanical and milling devices to assist in the removal of the moisture from the hydrated organic substrate while operating at a negative pressure within the drying system to create a non-volatile atmosphere for drying the organic substrate and for recirculating the gases to recover certain gases for reuse and to discharge other gases from the system to produce a quality dry distillers grain with solubles as a by-product for human or animal consumption.    The dehydration vessel is a mechanical centrifuge for removing water from the hydrated organic substrate. The mill is a mechanical mill including a chamber with a vacuum pipe to draw off the solvent vapors and other gases emitting from the organic substrate as it is dried to the predetermined moisture level where approximately 100% of the organic solvent is released from the dehydrated organic substrate and recovered for reuse through the vacuum pipe. The distillation tower is connected to the filtrate drain line from the dehydration vessel to further process and separate the water-solvent filtrate into its constituent parts of water and solvent for recovery of the organic solvent as a vapor and for discharge of the water from the tower and the apparatus while reducing regulated air emissions during the drying process.