Phosphorus recovery by struvite formation from al samra municipal wastewater treatment plant in jordan

Abstract

Struvite precipitation is a well-known problem in wastewater treatment plants (WWTPs) as it causes clogging in pumps and pipes. However, controlled struvite recovery from sewage sludge can reduce these problems. The special feature of the present study is the pilot-scale reactor applied to study the efficiency of the designed system in struvite recovery from anaerobic sludge supernatant produced at Al Samra WWTP in Jordan. Moreover, various operational parameters effects on struvite formation have been investigated. By adjusting the pH value between 8.5 and 9, the efficiency of phosphorus removal achieved from experimental runs reached about 77%. Best efficiencies were obtained at high mixing speed (300 rpm), low mixing time (0.5 h) and settling time in the range of 8–16 h. Efficiency was found to be directly proportional to mixing speed and inversely proportional to mixing time and settling time. Struvite formation was verified by X-ray diffraction tests.