Odors due to the emission of hydrogen sulfide (HS) have been a concern in the sewage treatment plants over the last decades. HS fate and emissions from extended aeration activated sludge (EAAS) system in Muharram Aisha-sewage treatment plant (MA-STP) were studied using TOXCHEM model. Sensitivity analysis at different aeration flowrate, HS loading rate, wastewater pH, wastewater temperature and wind speed were studied. The predicted data were validated against actual results, where all the data were validated within the limits, and the statistical evaluation of normalized mean square error (NMSE), geometric variance (VG), and correlation coefficient (R) were close to the ideal fit. The results showed that the major processes occurring in the system were degradation and emission. During summer (27 °C) and winter (12 °C), about 25 and 23%, 1 and 2%, 2 and 2%, and 72 and 73% were fated as emitted to air, discharged with effluent, sorbed to sludge, and biodegraded, respectively. At summer and winter, the total emitted concentrations of HS were 6.403 and 5.614 ppm, respectively. The sensitivity results indicated that aeration flowrate, HS loading rate and wastewater pH highly influenced the emission and degradation of HS processes compared to wastewater temperature and wind speed. To conclude, TOXCHEM model successfully predicted the HS fate and emissions in EAAS system.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7747736 | PMC |
http://dx.doi.org/10.1038/s41598-020-79395-8 | DOI Listing |
Sci Total Environ
December 2024
Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, School of Environmental Studies, China University of Geosciences, Wuhan 430074, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China.
To meet the challenge of water quality protection and management in the middle Yangtze River and understand the accumulation mechanism of PAHs in aquatic complexity systems, caused by hydro-chemical changes, anthropogenic and geological activities, and intensive surface water-groundwater interaction, a comprehensive study is urgently needed. The study investigated the pollution levels, potential sources, accumulation mechanism, and groundwater- surface water interaction of polycyclic aromatic hydrocarbons (PAHs) in wet and dry seasons of the middle Yangtze River. There was no significant difference of PAHs accumulation between wet and dry seasons of the middle Yangtze River.
View Article and Find Full Text PDFEJHaem
December 2024
Division of Hematology and Oncology, Department of Medicine University of Washington Seattle Washington USA.
Background: The tumor microenvironment (TME), including infiltrating T-cells, is thought to play a major role in the pathogenesis and prognosis of follicular lymphoma (FL) and may contribute to its widely varied disease course. We hypothesized that programmed death-1 inhibition may be most effective in untreated, immunocompetent FL patients. Thus, we developed a phase 2 study to evaluate the efficacy of pembrolizumab as the initial treatment for indolent B-cell lymphoma.
View Article and Find Full Text PDFEnviron Sci Technol
December 2024
School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Tire and road wear particles (TRWPs) are an appreciable source of microplastics (MPs); however, knowledge of their large-scale occurrence and mass flux based on robust sampling and quantification is limited. Herein, the first city-wide survey of TRWPs across environmental compartments (road dust, snowbank, water, and sediment from rivers and lakes) along four ring roads (beltways) in Beijing was performed. TRWP concentrations ( = 74) were quantified using bonded-sulfur as a marker to reveal the city-wide spatial distributions and adopted to establish a framework estimating TRWP emission factors (EFs) and mass flux from generation to remote atmospheric, terrestrial, and aquatic transport.
View Article and Find Full Text PDFMar Pollut Bull
December 2024
Finnish Meteorological Institute, Atmospheric Composition Research, P.O. Box 503, Helsinki FI-00101, Finland.
The ChemicalDrift model is applied to predict concentrations of metals and polycyclic aromatic hydrocarbons emitted from shipping in European seas in 2050, compared to 2018. Sources include antifouling paints (AFPs), discharge water from scrubbers and atmospheric deposition. The fate of pollutants in the marine environment is presented, highlighting the effect of degradation and volatilization, with seasonal and regional differences.
View Article and Find Full Text PDFSci Total Environ
December 2024
College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Key Laboratory of Yangtze River Water Environment, Ministry of Education, Shanghai 200092, China.
Seasonal fluctuations present significant challenges to drinking water treatment by altering the properties of Dissolved Organic Matter (DOM) within watersheds, thereby influencing the potential for disinfection by-product (DBP) formation. DOM is a complex mixture of organic matter that serves as a critical DBP precursor and is closely linked to adverse health outcomes. The prediction of DBP formation is complicated by the variability in DOM concentrations and compositions in lake source water, a situation exacerbated by seasonal changes in water systems.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!