In order to enhance the hydraulic loading rate （HLR） of a subsurface wastewater infiltration system （SWIS） used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results sh...In order to enhance the hydraulic loading rate （HLR） of a subsurface wastewater infiltration system （SWIS） used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results show that the intermittent operation mode contributes to the improvement of the HLR and the pollutant removal rate. When the wetting-drying ratio （RwD） was 1.0, the pollutant removal rate increased by （13.6 ± 0.3）% for NH3-N, （20.7 ± 1.1）% for TN, （18.6± 0.4）% for TP, （12.2 ± 0.5）% for BOD, （10.1 ± 0.3）% for COD, and （36.2 ± 1.2）% for SS, compared with pollutant removal rates under the continuous operation mode. The pollutant removal rate declined with the increase of the HLR. The effluent quality met The Reuse of Urban Recycling Water - Water Quality Standard for Scenic Environment Use （GB/T 18921-2002） even when the HLR was as high as 10 cm/d. Hydraulic conductivity, oxidation reduction potential （ORP）, the quantity of nitrifying bacteria, and the pollutant removal rate of NH3-N increased with the decrease of the RWD. For the pollutant removal rates of TP, BOD, and COD, there were no significant difference （p 〈 0.05） under different RwDS. The suggested RWD was 1.0. Relative contribution of the pretreatment and SWlS to the pollutant removal was examined, and more than 80% removal of NH3-N, TN, TP, COD, and BOD occurred in the SWIS.展开更多
The feasibility of using CASS technique for treating domestic sewage at low temperatures was investigated. The results indicate that for domestic sewage (averagely, ρ(BOD5)=295.7 mg/L; ρ(CODCr )= 811.7 mg/L; ρ(SS)=...The feasibility of using CASS technique for treating domestic sewage at low temperatures was investigated. The results indicate that for domestic sewage (averagely, ρ(BOD5)=295.7 mg/L; ρ(CODCr )= 811.7 mg/L; ρ(SS)= 119.6 mg/L), the removal rates are 95.3%, 85.7%, 91%, respectively. The CASS technique is operable in a wide range of temperature (about -5～20 ℃), but φ(S) and ρ(S) values are higher at low temperature than those at normal temperature. A low temperature is good for oxygen transmission and the cyclic fluctuation of DO (dissolved oxygen) is benefit for the removal of P and N, preventing the sludge from bulking.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51108275)the Program for Liaoning Excellent Talents in Universities(LNET)(Grant No.LJQ2012101)+2 种基金the Program for New Century Excellent Talents in Universities(Grant No.NCET-11-1012)the Science and Technology Program of Liaoning Province(Grants No.2011229002 and2013229012)the Basic Science Research Fund in Northeastern University(Grants No.N130501001 and N140105003)
文摘In order to enhance the hydraulic loading rate （HLR） of a subsurface wastewater infiltration system （SWIS） used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results show that the intermittent operation mode contributes to the improvement of the HLR and the pollutant removal rate. When the wetting-drying ratio （RwD） was 1.0, the pollutant removal rate increased by （13.6 ± 0.3）% for NH3-N, （20.7 ± 1.1）% for TN, （18.6± 0.4）% for TP, （12.2 ± 0.5）% for BOD, （10.1 ± 0.3）% for COD, and （36.2 ± 1.2）% for SS, compared with pollutant removal rates under the continuous operation mode. The pollutant removal rate declined with the increase of the HLR. The effluent quality met The Reuse of Urban Recycling Water - Water Quality Standard for Scenic Environment Use （GB/T 18921-2002） even when the HLR was as high as 10 cm/d. Hydraulic conductivity, oxidation reduction potential （ORP）, the quantity of nitrifying bacteria, and the pollutant removal rate of NH3-N increased with the decrease of the RWD. For the pollutant removal rates of TP, BOD, and COD, there were no significant difference （p 〈 0.05） under different RwDS. The suggested RWD was 1.0. Relative contribution of the pretreatment and SWlS to the pollutant removal was examined, and more than 80% removal of NH3-N, TN, TP, COD, and BOD occurred in the SWIS.
文摘The feasibility of using CASS technique for treating domestic sewage at low temperatures was investigated. The results indicate that for domestic sewage (averagely, ρ(BOD5)=295.7 mg/L; ρ(CODCr )= 811.7 mg/L; ρ(SS)= 119.6 mg/L), the removal rates are 95.3%, 85.7%, 91%, respectively. The CASS technique is operable in a wide range of temperature (about -5～20 ℃), but φ(S) and ρ(S) values are higher at low temperature than those at normal temperature. A low temperature is good for oxygen transmission and the cyclic fluctuation of DO (dissolved oxygen) is benefit for the removal of P and N, preventing the sludge from bulking.
