The invention relates to a biochemical simultaneous
phosphorus and
nitrogen removal method of domestic
sewage.
Sewage passes through a
grating and a primary
settling tank at first so that partial
suspended solids are removed, next, the
sewage passes through an
anaerobic filter tank loaded with iron
carbon filler and an aerobic filter tank, the
effluent of the aerobic filter tank flows back to the
anaerobic filter tank, organic matters in the
sewage in the anaerobic state are acidified so that the pH is reduced, an electrochemical reaction is aroused on the
surface layer of the iron
carbon filler to intensify
denitrification, and in the meantime, few
ferrous ions (Fe<2+>) are dissolved out; the
ferrous ions (Fe<2+>) are oxidized into
ferric ions (Fe<3+>) in the aerobic state, the
ferric ions react with soluble
phosphate radicals in the sewage to generate precipitate, and finally, the sewage enters a
sedimentation basin and is gravitationally settled, and then emitted. The biochemical simultaneous
phosphorus and
nitrogen removal method of domestic sewage, provided by the invention, has the advantages that no
reagent needs to be fed independently to remove
phosphorus, and only by virtue of the biochemical method, the COD (
Chemical Oxygen Demand) in the yielding water is lower than 30 mg / L, TN (
Total Nitrogen) in the yielding water is 1.5 mg / L and TP (
Total Phosphorus) in the yielding water is 0.2 mg / L, and consequently, the yielding water is up to the class IV water standards of
surface water. Furthermore, the biochemical simultaneous phosphorus and
nitrogen removal method of domestic sewage is simple in process, and capable of saving investment and operation costs, and thus has a great application value.