US 4,395,488 A · Drive-through pit production of ethanol

Abstract

Ethanol (C.sub.2 H.sub.5 OH) is produced efficiently by employing a drive-through pit in which carbohydrate-containing material is fermented by hydrolyzing agents such as enzymes. The configuration and depth of the pit are such as to permit conventional farm vehicles to have ready access to the pit, thereby enabling the pit to be loaded and unloaded conveniently. The pit is insulated on its sides and bottom and is closed at the top by a heat-insulating cover. The pit is heated to assist the fermentation process. After several days of heating, the pit is drained through a sediment trap and the filtered pit drainage is separated into concentrated ethanol and a mixture of water and enzymes. The solid residue left in the pit is removed for use as feed or fertilizer. The separated water and hydrolyzing agents are stored in a reservoir for subsequent flooding of the pit when a new quantity of carbohydrate-containing material is added to the pit.

Claims8

Dependent claims

A method for producing ethanol, comprising the steps of:

depositing carbohydrate-containing material into a pit having a bottom with one end lower than the other and heating pipes within grooves in the bottom below the surface of the bottom;
driving a vehicle into the pit and using it to spread said carbohydrate-containing material;
flooding the pit with a mixture of water and hydrolyzing agents until the material is covered with at least six inches of liquid;
fermenting the contents of the pit;
draining the liquid contents of the pit from the lower end of the pit;
separating the drained liquid into concentrated ethanol and a mixture of water and hydrolyzing agents;
removing the mixture of water and hydrolyzing agents for later use in flooding the pit;
and
driving a vehicle into the pit and removing the solid residue from the pit with the vehicle.

6 more elements

Apparatus for producing ethanol by the fermentation of carbohydrate-containing material, comprising:

a pit into which carbohydrates-containing material can be placed and flooded with a solution for producing ethanol;
a sediment trap adjacent the pit for draining the pit and removing solids from the drained liquid;
separation equipment for producing concentrated ethanol and a mixture of water and hydrolyzing agents;
a storage reservior for storing a mixture of water and hydrolyzing agents for subsequent use in producing ethanol;
a cover for the pit to seal the pit during the fermentation process;
said pit including a bottom wall, side walls and sloping end walls;
said bottom wall being impervious to liquids, the bottom wall being inclined with respect to the horizontal so that one end of the pit is deeper than the other;
said side walls extending upwardly from the bottom wall, the side walls being impervious to liquids;
said sloping end walls extending outwardly from the bottom wall at an angle to the horizontal, the end walls being impervious to liquids;
generally horizontal aprons extending laterally outwardly from the end walls;
a plurality of grooves formed in the bottom wall;
heating pipes located in the grooves, the heating pipes adapted to convey heated fluid so that the contents of the pit can be heated;
said grooves having a depth greater than the diameter of said pipes, whereby a vehicle may be driven over said bottom wall without rupturing said pipes;
and
a drainage gate formed in one of the side walls adjacent the deeper end of the pit.

12 more elements

Dependencies are inferred from the claim text.

Drive-through pit production of ethanol

Life of this patent

Drive-through pit production of ethanol

Life of this patent

Abstract

Claims8