REACTOR AND METHOD FOR THE ANAEROBIC TREATMENT OF SLUDGE CONTAINING PHOSPHOROUS AND NITROGEN

摘要

Thin sludge can be anaerobically digested with improved phosphate removal in the form of struvite by using a downflow anaerobic digestion reactor (1) which is operated with crystal seeding at the top and enhanced crystal removal at the bottom. The reactor has liquid inlet means (2) at the top, and an exit means (5) at the bottom, the bottom part of the reactor (1) being provided with a rotating scraper (70) capable of collecting solid material from the bottom of the reactor (1) and moving said collected material to said exit means. Magnesium (3) is added as necessary for optimum struvite formation.