Carbon cycle regulation and greenhouse gas(GHG)emission abatement within wastewater treatment plants(WWTPs)can theoretically improve sustainability.Currently,however,large amounts of external carbon sources used for d...Carbon cycle regulation and greenhouse gas(GHG)emission abatement within wastewater treatment plants(WWTPs)can theoretically improve sustainability.Currently,however,large amounts of external carbon sources used for deep nitrogen removal and waste sludge disposal aggravate the carbon footprint of most WWTPs.In this pilot-scale study,considerable carbon was preliminarily recovered from primary sludge(PS)through short-term(five days)acidogenic fermentation and subsequently utilized on-site for denitrification in a wool processing industrialWWTP.The recovered sludge-derived carbon sources were excellent electron donors that could be used as additional carbon supplements for commercial glucose to enhance denitrification.Additionally,improvements in carbon and nitrogen flow further contributed to GHG emission abatement.Overall,a 9.1%reduction in sludge volatile solids was achieved from carbon recovery,which offset 57.4%of external carbon sources,and the indirect GHG emissions of the target industrial WWTP were reduced by 8.05%.This study demonstrates that optimizing the allocation of carbon mass flow within a WWTP has numerous benefits.展开更多
Catalytic ozonation is regarded as a promising technology in the advanced treatment of refractory organic wastewater.Packed-bed reactors are widely used in practical applications due to simple structures,installation ...Catalytic ozonation is regarded as a promising technology in the advanced treatment of refractory organic wastewater.Packed-bed reactors are widely used in practical applications due to simple structures,installation and operation.However,mass transfer of packed-bed reactors is relatively restrained and amplified deviations usually occurred in scale-up application.Herein,a multi-scale packed-bed model of catalytic ozonation was established to guide pilot tests.First,a laboratory-scale test was conducted to obtain kinetic parameters needed for modeling.Then,a multi-scale packed-bed model was developed to research the effects of water distribution structure,catalyst particle size,and hydraulic retention time(HRT)on catalytic ozonation.It was found that the performance of packed bed reactor was increased with evenly distributed water inlet,HRT of 60 min,and catalyst diameter of about 3-7 mm.Last,an optimized reactor was manufactured and a pilot-scale test was conducted to treat kitchen wastewater using catalytic ozonation process.In the pilot-scale test with an ozone dosage of 50 mg/L and HRT of 60 min,the packed-bed reactor filled with catalysts I was able to reduce chemical oxygen demand(COD)from 117 to 59 mg/L.The performance of the catalytic ozonation process in the packed-bed reactor for the advanced treatment of actual kitchen wastewater was investigated via both multi-scale simulation and pilot-scale tests in this study,which provided a practical method for optimizing the reactors of treating refractory organic wastewater.展开更多
基金supported by the Key Research and Development Project of Shandong Province,China(2020CXGC011202-004)the State Key Laboratory of Urban Water Resources and Environment(Harbin Institute of Technology),China(No.2022TS26)the Shenzhen Science and Technology Innovation Program,China(KQTD20190929172630447).
文摘Carbon cycle regulation and greenhouse gas(GHG)emission abatement within wastewater treatment plants(WWTPs)can theoretically improve sustainability.Currently,however,large amounts of external carbon sources used for deep nitrogen removal and waste sludge disposal aggravate the carbon footprint of most WWTPs.In this pilot-scale study,considerable carbon was preliminarily recovered from primary sludge(PS)through short-term(five days)acidogenic fermentation and subsequently utilized on-site for denitrification in a wool processing industrialWWTP.The recovered sludge-derived carbon sources were excellent electron donors that could be used as additional carbon supplements for commercial glucose to enhance denitrification.Additionally,improvements in carbon and nitrogen flow further contributed to GHG emission abatement.Overall,a 9.1%reduction in sludge volatile solids was achieved from carbon recovery,which offset 57.4%of external carbon sources,and the indirect GHG emissions of the target industrial WWTP were reduced by 8.05%.This study demonstrates that optimizing the allocation of carbon mass flow within a WWTP has numerous benefits.
基金supported by the“Explorer 100”cluster system of Tsinghua HPC Platform.
文摘Catalytic ozonation is regarded as a promising technology in the advanced treatment of refractory organic wastewater.Packed-bed reactors are widely used in practical applications due to simple structures,installation and operation.However,mass transfer of packed-bed reactors is relatively restrained and amplified deviations usually occurred in scale-up application.Herein,a multi-scale packed-bed model of catalytic ozonation was established to guide pilot tests.First,a laboratory-scale test was conducted to obtain kinetic parameters needed for modeling.Then,a multi-scale packed-bed model was developed to research the effects of water distribution structure,catalyst particle size,and hydraulic retention time(HRT)on catalytic ozonation.It was found that the performance of packed bed reactor was increased with evenly distributed water inlet,HRT of 60 min,and catalyst diameter of about 3-7 mm.Last,an optimized reactor was manufactured and a pilot-scale test was conducted to treat kitchen wastewater using catalytic ozonation process.In the pilot-scale test with an ozone dosage of 50 mg/L and HRT of 60 min,the packed-bed reactor filled with catalysts I was able to reduce chemical oxygen demand(COD)from 117 to 59 mg/L.The performance of the catalytic ozonation process in the packed-bed reactor for the advanced treatment of actual kitchen wastewater was investigated via both multi-scale simulation and pilot-scale tests in this study,which provided a practical method for optimizing the reactors of treating refractory organic wastewater.