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Author      Title/Abstract      

Analysis of Organic Nitrogen Removal in Municipal Wastewater by Reverse Osmosis
Author: Rion Merlo, Joe Wong, Victor Occiano, Kyle Sandera, Anil Pai, Seval Sen, Jose Jimenez, Denny Parker and John Burcham
Date: 1/211
Preprint, Nutrient Recovery and Management 2011, January 9-12, 2011, Miami, FL

Organic nitrogen (Norg) removal by the reverse osmosis (RO) process is not well documented in the literature. Unlike inorganic nitrogen (i.e. ammonia, nitrate, nitrite), which is consistently removed across a RO membrane as a function of process operation (i.e. flux and recovery), pH and membrane type; the Norg removal will vary depending on its characteristics. Characteristics of Norg that could affect its removal include size, charge and hydrophobicity. The results of a pilot study that was conducted to determine the total nitrogen (TN) removal possible with the RO process are presented. The Norg removal rates are compared with removals observed from three full-scale RO facilities and four pilot studies. The results of this analysis suggest that RO may not consistently produced TN levels less than 1.0 mg/L without additional treatment. Biological nutrient removal (BNR) followed by RO treatment would be necessary to meet stringent TN limits. Additional processes such as coagulation or activated carbon may be necessary as well.