title: Removal of organic impurities in waste glycerol from biodiesel production process through the acidification and coagulation processes.
abstract: Treatment of waste glycerol, a by-product of the biodiesel production process, can reduce water pollution and bring significant economic benefits for biodiesel facilities. In the present study, hydrochloric acid (HCl) was used as acidification to convert soaps into salts and free fatty acids which were recovered after treatment. The pH value, dosages of polyaluminum chloride (PACl) and dosage of polyacrylamide (PAM) were considered to be the factors that can influence coagulation efficiency. The pH value of waste glycerol was adjusted to a pH range of 3-9. The PACl and PAM added were in the range of 1-6 g/L and 0.005-0.07 g/L. The results showed best coagulation efficiency occurs at pH 4 when dosage of PACl and PAM were 2 and 0.01 g/L. The removal of chemical oxygen demand (COD), biochemical oxygen demand (BOD(5)), total suspended solids (TSS) and soaps were 80, 68, 97 and 100%, respectively. The compositions of organic matters in the treated waste glycerol were glycerol (288 g/L), methanol (3.8 g/L), and other impurities (0.3 g/L).
authors.affiliation: Department of Civil Engineering, Prince of Songkla University, Hat Yai, Songkhla, Thailand.
authors.forename: Qiao-Guang
authors.initials: QG
authors.lastname: Xie
authors.forename: Wirach
authors.initials: W
authors.lastname: Taweepreda
authors.forename: Charongpun
authors.initials: C
authors.lastname: Musikavong
authors.forename: Chaisri
authors.initials: C
authors.lastname: Suksaroj
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000536:Aluminum Hydroxide / Q000737:chemistry; D056804:Biofuels; D057919:Biological Oxygen Demand Analysis; D005990:Glycerol / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D012915:Soaps / Q000302:isolation & purification; D018505:Waste Management / Q000379:methods*; D014866:Waste Products / Q000032:analysis; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D000536:Aluminum Hydroxide; D056804:Biofuels; D005990:Glycerol; D012915:Soaps; D014866:Waste Products; D000099166:Polyacrylamides; C016213:aluminum oxychloride