Study on the treatment of sewage mixed with partially-treated swine wastewater by a combined upflow anaerobic sludge blanket and constructed wetland process
A system with the combination of upflow anaerobic sludge blanket (UASB) reactor and constructed wetlands (CWLs) has not yet been applied for cleaning river water polluted by sewage and swine wastewater. In this study, a pilot system with an UASB reactor (effective working volume 2.5 liters) combined with two CWL reactors (effective working volumes 54.4 and 80 liters for CWL-1 and CWL-2, respectively) was used to test the feasibility for treating wastewater samples prepared by mixing 1 volume of sewage and 1 volume of partially-treated swine wastewater. In the system, the UASB reactor was seeded with an anaerobic sludge for sewage treatment and CWL-1 and CWL-2 were planted with emergent macrophyte (reed, Phragmites australis L.) and floating macrophyte (Pistia stratiotes L.), respectively.
Effects of hydraulic retention time (HRT) of the test wastewater in the UASB reactor on the removal efficacy of various pollutants were tested. HRTs of 6, 4, and 2 hours were set for the UASB for the first, second, and third experimental phases, respectively.
The tested influent wastewater had the following properties (unit in mg/L and the number in parentheses indicates the average value): total CODt 64-332 (179), soluble CODS 28-267 (129), soluble BODS 8-120 (70), SS 110-1330 (372), NH3-N 20-99 (48), NO3--N 1.2-11.9 (2.7), NO2--N 0-3.4 (1.0), total nitrogen TN 24.3-95.7 (56.8), PO43--P 0-10.4 (2.9), total phosphorus TP 5.1-52.1 (23.9), Cu 0.0-0.41 (0.13), Zn 0.05-0.73 (0.27), DO 0.2-2.7 (0.7), and pH 6.9-7.7 (7.4).
Effluents from the UASB reactor for the third phase test had average values of CODt 55, CODS 40, BODS 27, SS 93, NH3-N 42, NO3--N 2.6, NO2--N 0.5, TN 43.7, PO43--P 0.9, TP 17.2, Cu 0.08, Zn 0.07, DO 0.04, and pH 7.4. For the phase, effluents from the combined UASB-CWL1-CWL2 system had average values of CODt 21, CODS 16, BODS 10, SS 38, NH3-N 2, NO3--N 1.9, NO2--N 0.1, TN 11.3, PO43--P 2.6, TP 5.9, Cu 0.06, Zn 0.05, DO 5.4, and pH 7.6. The system has been shown to be economically and technically feasible for cleaning the test wastewater.
Advisor:none; none; none
School:National Sun Yat-Sen University
School Location:China - Taiwan
Source Type:Master's Thesis
Keywords:uasb constructed wetland swine wastewater sewage
Date of Publication:06/27/2007