Patent ID: 7485228

Claim:
A hybrid reactor for anaerobic waste water treatment, comprising: a plurality of porous carrier elements occupying at least part of the height of the hybrid reactor; a space in a lower portion of the hybrid reactor between the lower confines thereof and the carrier elements; an upper portion of the hybrid reactor between the upper confines thereof and the carrier elements; a supply line for waste water to be treated and to be introduced into the hybrid reactor for the first time; a discharge system for discharging treated waste water from the hybrid reactor, a central flow channel extending from the top of the hybrid reactor in downward direction from a first distance from the upper confines of the reactor to a second distance from the lower confines of the reactor; a space between the central flow channel and a wall of the hybrid reactor in which the carrier elements are positioned, the space extending for at least part of the height of the flow channel, the carrier elements forming a structured, ordered fixed bed to permit flow therethrough, the carrier elements being arranged with flow passages having a predetermined width range between adjacent carrier elements; a separator system located in the upper portion of the hybrid reactor below the discharge system, the separator system being structured to retain microorganisms floating in the waste water in the hybrid reactor and to separate water passed between the carrier elements into a first partial flow flowing into the central flow channel at the top end of the hybrid reactor, and a branched-off second partial flow; the hybrid reactor being structured to allow the waste water flow in the hybrid reactor in a loop through the central flow channel in downward direction, then through the space in the lower portion, then along the carrier elements in upward direction, and finally again into the central flow channel; and a recirculation system structured to withdraw water from the second partial flow and recirculate the withdrawn water into the waste water loop flow, the recirculation system including a withdrawal member positioned above a portion of the separator system and at a lower level than the discharge system.