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
Constructed wetlands(CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer(Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate(HLR) on the efficiency of eff...Constructed wetlands(CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer(Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate(HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions(salinity 7.4–7.6) at 3 different HLRs(0.762, 0.633, and 0.458 m d–1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen(by 81.03–92.81%) and nitrite nitrogen(by 99.40%–99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids(TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.展开更多
Anaerobic treatment model treats fish processing wastewater to be necessary for a small and medium factory that is very popular in Vietnam and other countries.Several techniques have been proposed.However,they are qui...Anaerobic treatment model treats fish processing wastewater to be necessary for a small and medium factory that is very popular in Vietnam and other countries.Several techniques have been proposed.However,they are quite expensive and hard to operate,especially in remote areas.In this study,the hydraulic retention times(HRT)including 3,5,and 7 hours with a various organic loading rate of 1.5 to 6.5 kg COD/m3/day were investigated.Biomass concentration as mix-liquor volatile suspended solid(MLVSS)in the model is at 6,000 to 9,000 mg/L.On the basis of the result the optimal HRT with a 4.0 kg COD/m3/day organic loading rate was 8 hours which BOD5,COD removal efficiency were 92.18,87.36 percent respectively.By the end of the optimal hydraulic retention times,the total methane gas volume as a by-product was collected with 2.6 liters.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.
基金supported by the Agriculture Commission and the Sciences and Technology Commission of Shanghai(No.09ZR1429000)Shanghai University Knowledge Service Platform,Shanghai Ocean University aquatic animal breeding center(ZF1206),China
文摘Constructed wetlands(CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer(Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate(HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions(salinity 7.4–7.6) at 3 different HLRs(0.762, 0.633, and 0.458 m d–1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen(by 81.03–92.81%) and nitrite nitrogen(by 99.40%–99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids(TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.
文摘Anaerobic treatment model treats fish processing wastewater to be necessary for a small and medium factory that is very popular in Vietnam and other countries.Several techniques have been proposed.However,they are quite expensive and hard to operate,especially in remote areas.In this study,the hydraulic retention times(HRT)including 3,5,and 7 hours with a various organic loading rate of 1.5 to 6.5 kg COD/m3/day were investigated.Biomass concentration as mix-liquor volatile suspended solid(MLVSS)in the model is at 6,000 to 9,000 mg/L.On the basis of the result the optimal HRT with a 4.0 kg COD/m3/day organic loading rate was 8 hours which BOD5,COD removal efficiency were 92.18,87.36 percent respectively.By the end of the optimal hydraulic retention times,the total methane gas volume as a by-product was collected with 2.6 liters.