Two-phase anaerobic digestion of carbonaceous organic materials
AssigneeInstitute of Gas Technology
InventorVipul J. Srivastava
Life of this patent
Estimating the term…
Abstract
A process for improved methane production by two-phase anaerobic digestion of organic carbonaceous material in which organic carbonaceous material is fermented under anaerobic conditions in an acid phase digester, forming a liquid/solids effluent, the liquid/solids effluent is fermented under anaerobic conditions in a methane phase digester, product gas comprising methane is withdrawn from the methane phase digester, and oxygen is introduced into the methane phase digester. In a preferred embodiment, the methane phase liquid effluent is passed through a CO.sub.2 stripper resulting in stripping of CO.sub.2 and H.sub.2 S from the methane phase liquid effluent. The resulting stripper liquid effluent comprising dissolved oxygen is then recycled back to the methane phase digester.
Claims13
A process for improved methane production by two-phase anaerobic digestion of organic carbonaceous material comprising the steps of:
- introducing said organic carbonaceous material into an acid phase digester;
- fermenting said organic carbonaceous material in said acid phase digester under anaerobic conditions, forming a liquid/solids effluent;
- passing said liquid/solids effluent to a methane phase digester;
- fermenting said liquid/solids effluent in said methane phase digester under anaerobic conditions and withdrawing gas comprising methane from said methane phase digester;
- passing a methane phase liquid effluent to a CO.sub.2 stripper and stripping CO.sub.2 and H.sub.2 S from said methane phase liquid effluent;
- and
- introducing a stripper liquid effluent comprising dissolved oxygen into said methane phase digester.
In a two-phase anaerobic digestion process for improved methane production in which an organic carbonaceous material is fermented in an acid phase digester and a liquid/solids effluent from said acid phase digester is fermented in a methane phase digester forming a gas comprising methane and a liquid effluent, the improvement comprising:
- introducing oxygen into a liquid phase of said methane phase digester.
Dependencies are inferred from the claim text.