APPARATUS AND METHOD FOR REMOVING PHOSPHORUS FROM WASTE LAGOON EFFLUENT

摘要

An apparatus (10) and method for removing phosphorus from a wastewatereffluent stream (16) from a hog waste lagoon is disclosed. The wastewatereffluent (16) is introduced to the bottom of an inverted cone-shapedcontinuous crystallizer (12) including a fluidized bed of struvite therein. Aneffective amount of ammonia (20) is introduced to the wastewater effluent (16)at the bottom of the crystallizer (12) to elevate the pH of wastewatereffluent (16) a predetermined amount. An effective amount of magnesium (18) isalso introduced to the wastewater effluent (16) at the bottom of thecrystallizer (12). The composition adjusted wastewater effluent is thencontinuously passed upwardly through the fluidized bed of struvite to reducethe total phosphorus content of the wastewater effluent (16) a predeterminedamount of up to about 80 % or more. The treated wastewater effluent stream(24) is removed from the top of the crystallizer (12), and struvite crystalsthat grow large enough to sink from the bottom of the crystallizer (12) areperiodically removed from a collection chamber (22) therebeneath.