Title: Control of Struvite (Magnesium Ammonium Phosphate) Scale in Wastewater Treatment Plants
Learner Objectives:
This study deals with the struvite scale control by synthetic, hybrid, and biodegradable polymers in wastewater treatment plants
Content/Topic Outline:
Presenter:
Zahid Amjad, PhD
Presentation Description:
Higher levels of phosphate in wastewater are responsible both for the deterioration of the water quality of natural water sources and for the formation of undesirable deposit on the various equipment and parts of machinery used during the wastewater treatment processes. Phosphate concentrations in wastewater, both industrial and municipal, may increase due to intensive soil fertilization, domestic, and industrial processes. In some cases, the phosphate concentrations in treated water may be sufficiently high to cause the formation and deposition of undesirable scale formed due to the interaction of phosphate ions with metal ions such as magnesium, calcium, and iron which may present in excess in wastewater. Additionally, the higher concentrations of phosphate, ammonia, and magnesium present in wasted sludge can result in the formation of scale called struvite (magnesium ammonium phosphate, MgNH4PO4.6H2O). The Formation of struvite scale is detrimental since it clogs pipes, reducesefficiencies of heat exchangers, and restricts flow in surface aerators. Struvite formation causing scaling problems have been reported in the biological treatment of hog and poultry wastes, in wine distillery effluents and in biosolids from biological phosphorus removal processes.
In the present work we have investigated the effect of a variety of polymeric additives containing different functional groups, monomer ratios, and molecular weights, on struvite precipitation under spontaneous precipitation conditions using synthetic synthetic wastewater solution. The results reveal that struvite inhibition is strongly influenced by polymer architecture. Struvite crystals formed in the absence and presence of inhibitor were characterized by x-ray diffraction and scanning electron microscopy.
Presenter Bio:
Dr. Amjad is a Visiting Professor in the Chemistry Department and has over 40+ years of water treatment and chemical industry experience.
Education:
Work Experience:
Current Focus on Research:
Crystal growth and dissolution phenomena with applications in scale formation and inhibition in industrial and biological systems, toxic substances removal from aqueous streams, solid/liquid separation, water purification processes, scale removal, etc.
Professional Organization Memberships, Affiliations, Awards:
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