Pressurized digester vessel

A pressurized digester biogas reactor comprising:

• a mixing tank having a bottom, sides and a top;
• a bottom portion of the tank having a smaller diameter than a central portion of the tank;
• a double channel central draft tube;
• a pump forcing an inlet fluid downward through a central channel in the double channel central draft tube into the bottom portion of the tank;
• said central channel having a primary nozzle facing downstream;
• an outer draft channel housing the central channel;
• wherein an annular space between the outer draft channel and the central channel forms a secondary channel;
• said outer draft channel having a secondary nozzle facing downstream;
• wherein said primary nozzle is located above said secondary nozzle, and both nozzles share a common longitudinal axis;
• said outer draft channel having an inlet weir for channeling a mixing tank fluid into the secondary channel;
• wherein the pump supplies a minimum of twenty feet per second flowrate to the inlet fluid;
• wherein said minimum twenty feet per second flowrate forms a vacuum at a bottom end of the outer draft channel;
• wherein said vacuum induces the mixing tank fluid into the weir and out the secondary nozzle;
• wherein a combined flow from the primary and secondary nozzles impinge the bottom of the mixing tank;
• a slurry in the tank producing a biogas;
• a pressure controller located at a top portion of the tank to maintain an operating pressure in the tank in the range of about 30 to 100 psi;
• said bottom portion of the tank having a heater;
• said pump having an inlet in a central mixing zone of the tank for the inlet fluid;
• and
• said central mixing zone having a slurry outlet to release liquids therefrom.