Inorganic Solid Precipitation Model for Anaerobic Digestion Liquor
A computation model for inorganic composition of mesophillic anaerobically digested sludge was developed using 9 datasets taken from digesters at 9 different wastewater treatment plants. The model employed some assumptions and calibration parameters based on stoichiometry and kinetics, combined with thermodynamic equilibrium computation. Through the model development process, (1) the primarily precipitating solid species for Ca, Mg and Fe were determined to be CaHPO4, Mg(NH4)PO4·6H2O and FeCO3, respectively; (2) phosphorous (P), Ca and Mg contents in sludge biomass were estimated to be 1％ of digested sludge volatile solid, respectively; (3) A1(OH)3 was adsorbed by P with 0.05 mol-P/mol-Al (OH)3; (4) CaHPO4 and FeCO3 were assumed to experience slow solid-to-solid reaction to CaCO3 and Fe3(PO4)28H2O with first-order reaction rates of 0.05 day1 and 0.01 day1, respectively. The developed model successfully reproduced aqueous P, Ca and Mg concentrations of the datasets. The model predicted typical inorganic composition of digested sludge inside anaerobic digester as P (aqueous = 52％, inorganic solid = 20％), Ca (aqueous = 5％, inorganic solid = 65％) and Mg (aqueous = 52％, inorganic solid = 6％).
Anaerobic digestion inorganic precipitation thermodynamics modelling
Daisuke Naka Rajeev Goel Hidenari Yasui
Faculty of Environmental Engineering, the University of Kitakyushu, 1-1 Hibikino,Wakamatsu, Kitakyus Hydromantis Environmental Software Solutions, Inc., 1 James Street South,Suite 1601, Hamilton, Ontar Faculty of Environmental Engineering, the University of Kitakyushu, 1-1 Hibikino, Wakamatsu, Kitakyu
国际会议
天津
英文
215-224
2011-11-12（万方平台首次上网日期，不代表论文的发表时间）