PROCESS FOR PRODUCING ETHANOL AND FOR ENERGY RECOVERY

• US 20080003654A1
• Filed: 08/28/2007
• Published: 01/03/2008
• Est. Priority Date: 12/19/2005
• Status: Active Grant

• Current Assignee: Stanley Consultants Incorporated (SC Companies Incorporated)
• Original Assignee: Stanley Consultants Incorporated (SC Companies Incorporated)
• Inventors: Hirl, Patrick
• Granted Patent: US 7,524,418 B2
• Time in Patent Office: Days
• US Class Current: 435/162
• CPC Class Codes: C05F 17/00 Preparation of fertilisers characterised by biological or biochemical treatment steps, e.g. composting or fermentation
• CPC Class Codes: C05F 5/008 Waste from biochemical processing of material, e.g. fermentation, breweries
• CPC Class Codes: C12M 21/04 for producing gas, e.g. biogas digesters for manure with production of biogas A01C3/028, biological treatment of water, waste water or sewage C02F3/00, C02F11/02, preparation of natural gas or syngas C10L3/06, C10L3/10
• CPC Class Codes: C12M 21/12 for producing fuels or solvents C12M21/04 takes precedence; liquid carbonaceous fuels C10L1/00, solid fuels C10L5/00
• CPC Class Codes: C12M 43/08 Bioreactors or fermenters combined with devices or plants for production of electricity
• CPC Class Codes: C12P 5/023 Methane
• CPC Class Codes: C12P 7/06 Ethanol, i.e. non-beverage
• CPC Class Codes: Y02A 40/20 Fertilizers of biological origin, e.g. guano or fertilizers made from animal corpses
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02E 50/30 Fuel from waste, e.g. synthetic alcohol or diesel
• CPC Class Codes: Y02P 20/129 Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
• CPC Class Codes: Y02P 20/145 the feedstock being materials of biological origin
• CPC Class Codes: Y02P 20/59 Biological synthesis; Biological purification
• CPC Class Codes: Y02W 30/40 Bio-organic fraction processing; Production of fertilisers from the organic fraction of waste or refuse

Abstract

The present invention is directed to a process for the production of ethanol and energy. The process includes the steps of fermenting a corn mash in an aqueous medium to produce a beer. Next, the beer is distilled to produce ethanol and a whole stillage. The whole stillage is anaerobically digested to produce a biogas and a residue. The biogas is combusted to produce electricity and steam. The electricity and steam are used during the fermentation and distillation process. The residue may further be separated into a liquid fertilizer and top soil residue.

Claims

1. An integrated continuous process for the production of ethanol and energy comprising:

fermenting a corn mash in an aqueous medium to produce a beer;

distilling said beer to produce ethanol and a whole stillage;

digesting a mixture containing said whole stillage anaerobically to produce a biogas and a residue;

combusting said bio-gas to produce electricity and steam;

utilizing the electricity produced by said combustion during the steps of fermenting and distilling to produce said ethanol; and

utilizing the steam produced by said combustion during the step of fermenting the corn mash.

2. The process of claim 1 further comprising:

dehydrating the distilled ethanol to produce an ethanol with a higher proof then said distilled ethanol, wherein during the dehydrating step water is recovered; and

utilizing the recovered water during the step of distilling.

3. The process of claim 1 further comprising mixing the whole stillage with bacteria and water prior to digesting.

4. The process of claim 3 further comprising the steps:

separating the residue from the digestion step into digested liquids and digested sludge, and

recycling bacteria from said digested sludge into the whole stillage.

5. The process of claim 4 further comprising the step:

dewatering the digested sludge to produce a soil amendment and a water residue, and

recycling said water residue from the dewatering step into the whole stillage.

6. The process of claim 4 further comprising the steps:

stripping ammonia from the digested liquid to produce an ammonia rich air stream; and

scrubbing said ammonia rich air stream to produce an aqueous ammonia fertilizer.

7. The process of claim 6 further comprising the step of recycling water from the digested liquid following ammonia stripping into the whole stillage.