Biofuel production involves returning methane from sludge gasification reactor to sludge anaerobic treatment stage, where it is mixed with nascent biogas

摘要

Biogas is generated by sludge gasification reactor and is returned to the aerobic treatment stage where it is mixed with the nascent biogas. The sludge is gasified at between 400 and 1200 deg C producing primarily methane. The mixture is drawn from the anaerobic reactors for use as fuel. Foul sludge stage (11) biogas and anaerobic stage biogas circulate between the reactors before it is drawn off for use as a fuel. An Independent claim is also included for a sludge treatment assembly, comprising an anaerobic stage (3, 4), a foul sludge thickener (5), a foul sludge homogenizer (6), a de-watering unit (7), a foul sludge stacking container (8), a sludge drier (9), a dry sludge store (10) and a sludge gasifier (11). The assembly has a pipe linking the foul sludge gasifier to the anaerobic stage containers.