Apparatus, system, and process for anaerobic conversion of biomass slurry to energy

An improved digester apparatus for converting wet carbonaceous biomass materials to biogas comprising gaseous organic fuel, said apparatus comprising a digestion unit operating at a controlled temperature and having a concentrator component and a pressure swing component each containing anaerobic bacteria;

• means for conveying slurried aqueous biomass from a biomass source to said concentrator component;
• means for removing said biogas from said concentrator component;
• means for conveying concentrated aqueous biomass from said concentrator component to said pressure swing component and means for conveying digested aqueous biomass from said pressure swing component to said concentrator component, thereby forming a closed loop between said concentrator and pressure swing components;
• means for removing waste solids from said pressure swing component;
• and pressure swing pump means for controlling the pressure within said pressure swing component in a cycle comprising a first phase having a first time duration at a sub-atmospheric first pressure and a second phase having a second time duration and a second pressure at or above atmospheric pressure;
• wherein the improvement comprises:
• inclusion in said apparatus of programmable computer means provided with a database comprising previously acquired data relating biomass-biogas conversion for biomass materials of varying compositions to values for said first and second, respectively, pressures and time durations of said first and second phases,
• said programmable computer means for continuously monitoring the pressure of biogas in said pressure swing component and to adjust said first and second phases in said cycle of said pressure swing pump means to optimize biogas conversion of biomass from said biomass source.