US Patent 7708884 Process for aerobic-thermophilic stabilization and disinfection of sludge

A process for the stabilization and disinfection of sludge whereina) raw sludge having a dry matter content of from 3 to 7% by weight is fed continuously or quasi-continuously into a first stage, where it remains for an average retention time of three to ten days under aerobic-thermophilic conditions to obtain a partially stabilized sludge; andb) the partially stabilized sludge is fed into a second stage in which disinfection of the partially stabilized sludge is effected at temperatures of at least 50° C., wherein prior to discharging, there is no charging until the partially stabilized sludge has been disinfected.