title: Process development for scum to biodiesel conversion.
abstract: A novel process was developed for converting scum, a waste material from wastewater treatment facilities, to biodiesel. Scum is an oily waste that was skimmed from the surface of primary and secondary settling tanks in wastewater treatment plants. Currently scum is treated either by anaerobic digestion or landfilling which raised several environmental issues. The newly developed process used a six-step method to convert scum to biodiesel, a higher value product. A combination of acid washing and acid catalyzed esterification was developed to remove soap and impurities while converting free fatty acids to methyl esters. A glycerol washing was used to facilitate the separation of biodiesel and glycerin after base catalyzed transesterification. As a result, 70% of dried and filtered scum was converted to biodiesel which is equivalent to about 134,000 gallon biodiesel per year for the Saint Paul waste water treatment plant in Minnesota.
authors.affiliation: College of Engineering, China Agricultural University, Beijing 100083, China; Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, USA.
authors.forename: Chong-hao
authors.initials: CH
authors.lastname: Bi
authors.affiliation: Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, USA. Electronic address: minxx039@umn.edu.
authors.forename: Min
authors.initials: M
authors.lastname: Min
authors.affiliation: College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Nie
authors.affiliation: Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, USA.
authors.forename: Qing-long
authors.initials: QL
authors.lastname: Xie
authors.affiliation: Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, USA.
authors.forename: Qian
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, USA.
authors.forename: Xiang-yuan
authors.initials: XY
authors.lastname: Deng
authors.affiliation: Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, USA.
authors.forename: Erik
authors.initials: E
authors.lastname: Anderson
authors.affiliation: College of Engineering, China Agricultural University, Beijing 100083, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Li
authors.affiliation: Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Chen
authors.affiliation: Center for Biorefining, and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Avenue, St. Paul, MN 55108, USA. Electronic address: ruanx001@umn.edu.
authors.forename: Roger
authors.initials: R
authors.lastname: Ruan
mesh_terms: D000143:Acids / Q000737:chemistry; D056804:Biofuels; D003247:Conservation of Natural Resources / Q000379:methods; D004951:Esterification; D005230:Fatty Acids, Nonesterified / Q000737:chemistry*; D005990:Glycerol / Q000737:chemistry*; D012037:Refuse Disposal / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D000143:Acids; D056804:Biofuels; D005230:Fatty Acids, Nonesterified; D005990:Glycerol; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Acid washing; Biodiesel; Glycerol washing; Scum; Wastewater treatment plant