Combined anaerobic digester and GTL system and method of use thereof

• US 10,240,119 B2
• Filed: 05/06/2016
• Issued: 03/26/2019
• Est. Priority Date: 05/06/2015
• Status: Active Grant

• Current Assignee: Maverick BioFuels, Inc.
• Original Assignee: Maverick BioFuels, Inc.
• Inventors: Bradin, David, Yenne, Samuel, Cumming, Eric, Harrison, Jeffrey
• Primary Examiner(s): Witherspoon, Sikarl A
• Application Number:
  US15/572,034
• Publication Number:
  US 20180135004A1
• Time in Patent Office: 1,054 Days
• CPC Class Codes: C01B 2203/02 Processes for making hydrogen or synthesis gas
• CPC Class Codes: C01B 2203/0216 containing a non-catalytic steam reforming step
• CPC Class Codes: C01B 2203/061 Methanol production
• CPC Class Codes: C01B 2203/062 Hydrocarbon production, e.g. Fischer-Tropsch process
• CPC Class Codes: C01B 3/24 of hydrocarbons
• CPC Class Codes: C07C 1/041 Reactors
• CPC Class Codes: C07C 29/1518 one step being the formation of initial mixture of carbon oxides and hydrogen for synthesis
• CPC Class Codes: C07C 31/04 Methanol
• CPC Class Codes: C07C 45/002 by dehydrogenation
• CPC Class Codes: C07C 45/29 of hydroxy groups
• CPC Class Codes: C07C 47/04 Formaldehyde
• CPC Class Codes: C10G 2/32 with the use of catalysts
• CPC Class Codes: C10G 2300/1011 Biomass
• CPC Class Codes: C12F 3/04 Recovery of volatile fermentation products from carbon dioxide
• 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 27/02 Stirrer or mobile mixing elements
• CPC Class Codes: C12M 41/18 Heat exchange systems, e.g. heat jackets or outer envelopes
• CPC Class Codes: C12M 43/00 Combinations of bioreactors or fermenters with other apparatus
• CPC Class Codes: C12P 5/023 Methane
• CPC Class Codes: C12P 7/6409 Fatty acids
• CPC Class Codes: C12P 7/6463 : obtained from glyceride producing microorganisms, e.g. single cell oil
• CPC Class Codes: C12P 7/649 : Biodiesel, i.e. fatty acid alkyl esters
• 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 20/10 : Process efficiency
• CPC Class Codes: Y02P 30/20 : using bio-feedstock

Abstract

A combined anaerobic digester system and gas-to-liquid system is disclosed. The anaerobic digester requires heat, and produces methane. The gas-to-liquid system produces heat, and converts methane to higher-value products, including methanol and formaldehyde. As such, the combination of the two systems results in significant savings in terms of capital and operating expenses. A process for producing bio-formaldehyde and bio-formalin from biogas is also disclosed.

Claims

1. A system for producing bioproducts, comprising an anaerobic digester that converts biomass to a mixture of gases comprising methane and carbon dioxide, coupled with a syngas generator capable of converting the methane to a mixture of carbon monoxide and hydrogen, and a gas-to-liquid reactor capable of converting the carbon monoxide and hydrogen to hydrocarbon products selected from the group consisting of alcohols, formaldehyde, formalin, low molecular weight (C_2-5) olefins and paraffins, and C_20-50 paraffins, further comprising heat exchangers to transport heat produced in the gas-to-liquid reactor to the anaerobic digester, wherein the syngas generator is an autothermal reformer or a steam reformer.

2. The system of claim 1, further comprising a steam autoclave unit adapted to receive biomass, autoclave the biomass, and transport the biomass to the anaerobic digester.

3. The system of claim 1, further comprising a cavitation stirrer adapted to receive biomass, and stir the biomass at extremely high speeds, under cavitation.

4. The system of claim 1, further comprising a pressure swing absorption unit to remove carbon dioxide from the mixture of gases produced by the anaerobic digester.

5. The system of claim 1, further comprising a reactor for growing algae or cyanobacteria, wherein the reactor is adapted to receive carbon dioxide from the anaerobic digester and/or the gas-to-liquid reactor.

6. The system of claim 1, wherein the gas-to-liquid reactor comprises a catalyst suitable for converting a mixture of carbon monoxide and hydrogen to methanol, dimethyl ether, low molecular weight (C_2-5) olefins and paraffins, or C_20-50 paraffins.

7. The system of claim 1, wherein the product is methanol, and wherein the system further comprises a reactor and catalyst for converting the methanol to formaldehyde.

8. The system of claim 5, further comprising a reactor for recovering oils from the algae.

9. The system of claim 8, further comprising a reactor for converting oils produced by algae, or fatty acids produced by cyanobacteria, to biodiesel fuel.

10. A method for producing bio-formaldehyde, comprising the steps of:

a) converting biogas to syngas,

b) converting the syngas to methanol, and

c) converting the methanol to formaldehyde wherein the methanol is formed using the system of claim 1.

11. The method of claim 10, wherein the biogas is derived, in whole or in part, from the anaerobic digestion of animal waste.

12. The method of claim 11, wherein the process for producing methanol is exothermic, further comprising the step of transferring excess heat energy from the exothermic methanol producing step to an anaerobic digester, which anaerobic digester performs the anaerobic digestion of the animal waste.

13. The method of claim 10, further comprising converting all or part of the bio-formaldehyde to bio-formalin.