THWRC Awarded Proposal 515UTA0051H

Project Number:       515UTA0051H

Title:                           Impact of Coagulation on Biofiltration:  Simultaneous of Multiple Chemical

                                  Contaminants

Lead PI:                     Mary Jo Kirisits

Awarded Amount:    $50,000

ABSTRACT

A key problem in the drinking-water industry is to find effective treatment processes to remove an increasing variety and concentration of trace organic compounds (e.g., endocrine disruptors, pharmaceuticals, personal care products, and taste and odor compounds), many of which occur due to increased wastewater influence. The benefits of biofiltration including particle removal, biodegradation, and adsorption, make it an attractive process for addressing this problem. Biofiltration must be studied holistically, including its common upstream process of coagulation. Coagulation impacts the type and amount of organic matter entering the biofilter; this could influence microbial community structure and biodegradation, with implications for the removal of trace organics, trihalomethane formation potential and total/dissolved organic carbon. 

            The goal of proposed work is to develop a holistic understanding of coagulation-biofiltration. Specific objectives are to examine the impact of coagulant type and pH/dose on the simultaneous removal of multiple trace organic compounds by biofiltration and on the biofilter microbial community. To meet these objectives, a 23-month project ($50,000) is proposed, which will be divided into three tasks. Task 1 (partially completed) is to prepare key materials for the project, including choosing the suite of trace organic compounds and to concentrate natural organic matter for the coagulation-biofilter studies. Task 2 is to examine the impact of two coagulants (ferric chloride and alum) and pH/dose (optimized for enhanced coagulation or not optimized) on the removal of the trace organic compounds by biofiltration. Task 3 is to examine the impact of those same coagulation conditions on the structure of the biofilter microbial community. Together, these data will show if coagulation can be tailored to influence community composition and to maximize the overall removal of trace organic compounds in the combined coagulation-biofiltration process; if this link exists, practical guidance can be given to utilities that need to improve their removal of multiple trace organic compounds.