Molecular Evidence of Arsenic Mobility Linked to Biodegradable Organic Matter

2020 ◽  
Vol 54 (12) ◽  
pp. 7280-7290 ◽  
Author(s):  
Wen Qiao ◽  
Huaming Guo ◽  
Chen He ◽  
Quan Shi ◽  
Wei Xiu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Molecular Evidence ◽  
Arsenic Mobility ◽  
Biodegradable Organic Matter

Biomarker assessment of spatial and temporal changes in the composition of flocculent material (floc) in the subtropical wetland of the Florida Coastal Everglades

2013 ◽  
Vol 10 (5) ◽  
pp. 424 ◽  
Author(s):  
Oliva Pisani ◽  
J. William Louda ◽  
Rudolf Jaffé
Keyword(s):  
Organic Matter ◽  
Nutrient Cycling ◽  
Florida Everglades ◽  
Molecular Evidence ◽  
Seasonal Differences ◽  
Freshwater Marshes ◽  
Microbial Biomarkers ◽  
Spatial Differences ◽  
Dry Down ◽  
Flocculent Material

Environmental context Flocculent material (floc) in freshwater and coastal areas of the Florida Everglades plays an important role in food web dynamics and nutrient cycling. Using biomarkers and pigment chemotaxonomy, we determined the organic matter composition of floc from different environments in the Everglades, and found that it is dominated by local biomass inputs and influenced by hydrological regimes. With the on-going restoration of the Florida Everglades, it is important to gain a better understanding of the biogeochemical dynamics of floc, including its sources, transformations and reactivity. Abstract Flocculent material (floc) is an important energy source in wetlands. In the Florida Everglades, floc is present in both freshwater marshes and coastal environments and plays a key role in food webs and nutrient cycling. However, not much is known about its environmental dynamics, in particular its biological sources and bio-reactivity. We analysed floc samples collected from different environments in the Florida Everglades and applied biomarkers and pigment chemotaxonomy to identify spatial and seasonal differences in organic matter sources. An attempt was made to link floc composition with algal and plant productivity. Spatial differences were observed between freshwater marsh and estuarine floc. Freshwater floc receives organic matter inputs from local periphyton mats, as indicated by microbial biomarkers and chlorophyll-a estimates. At the estuarine sites, the floc is dominated by mangrove as well as diatom inputs from the marine end-member. The hydroperiod (duration and depth of inundation) at the freshwater sites influences floc organic matter preservation, where the floc at the short-hydroperiod site is more oxidised likely due to periodic dry-down conditions. Seasonal differences in floc composition were not consistent and the few that were observed are likely linked to the primary productivity of the dominant biomass (periphyton in the freshwater marshes and mangroves in the estuarine zone). Molecular evidence for hydrological transport of floc material from the freshwater marshes to the coastal fringe was also observed. With the on-going restoration of the Florida Everglades, it is important to gain a better understanding of the biogeochemical dynamics of floc, including its sources, transformations and reactivity.

Wastewater nitrogen removal in SBRs, applying a step-feed strategy: from lab-scale to pilot-plant operation

2004 ◽  
Vol 50 (10) ◽  
pp. 89-96 ◽  
Author(s):  
S. Puig ◽  
M.T. Vives ◽  
Ll. Corominas ◽  
M.D. Balaguer ◽  
J. Colprim
Keyword(s):  
Organic Matter ◽  
Nitrogen Removal ◽  
Pilot Plant ◽  
Batch Reactor ◽  
Aerobic Oxidation ◽  
Scaling Up ◽  
Plant Operation ◽  
Feed Strategy ◽  
Real Wastewater ◽  
Biodegradable Organic Matter

One of the problems of nitrogen removal from wastewater when applying sequencing batch reactor (SBR) technology, is the specific use of organic matter for denitrification purposes. Since easily biodegradable organic matter is rapidly consumed under aerobic or anoxic conditions (i.e. aerobic oxidation or anoxic denitrification, respectively), it is an important factor to consider when scaling up SBRs from the laboratory to real plant operation. In this paper, we present the results obtained in relation to scaling up reactors from lab-scale to pilot-plant scale, treating real wastewater from two different locations: the laboratory and in situ, respectively. In order to make using easily biodegradable organic matter more efficient, the filling phases of SBR cycles were adjusted according to a step-feed strategy composed of 6 anoxic-aerobic events. Feeding only occurred during anoxic phases. The results obtained demonstrated that the methodology may be useful in treating real wastewater with high carbon and nitrogen variations, as it always kept effluent levels lower than the official standards require (effluent total COD lower than 125 mg COD/L and effluent Total Nitrogen lower than 15 mg N/L).

Biodegradable organic matter removal in biological filters: evaluation of the CHABROL model

1999 ◽  
Vol 33 (6) ◽  
pp. 1387-1398 ◽  
Author(s):  
Patrick Laurent ◽  
Michèle Prévost ◽  
John Cigana ◽  
Patrick Niquette ◽  
Pierre Servais
Keyword(s):  
Organic Matter ◽  
Organic Matter Removal ◽  
Biological Filters ◽  
Biodegradable Organic Matter

scholarly journals Reducción de la carga orgánica de aguas residuales tóxicas de los laboratorios de la unas mediante oxidación avanzada Foto – Fenton

2018 ◽  
pp. 31-41
Keyword(s):  
Waste Water ◽  
Organic Matter ◽  
Soil Analysis ◽  
Organic Matter Content ◽  
Matter Content ◽  
Toxic Waste ◽  
Significant Variable ◽  
Total Phenols ◽  
La Selva ◽  
Biodegradable Organic Matter

Reducción de la carga orgánica de aguas residuales tóxicas de los laboratorios de la unas mediante oxidación avanzada Foto – Fenton Gian Marco Castillo Avila, José Antonio Blaz Matienzo Universidad Nacional Agraria de la Selva, Av. Universitaria Km. 1.5 s/n, Tingo María-Perú Resumen Se investigó la reducción de la materia orgánica contenida en aguas residuales tóxicas proveniente de siete laboratorios de la Universidad Nacional Agraria de la Selva (Química General e Inorgánica, Fitoquimica, Análisis de Suelos, Bioquímica, Microscopia y Sanidad Animal) mediante el proceso Foto-Fenton solar. Para optimizar el proceso, se utilizó la metodología de superficie de respuesta, estudiando el efecto de los factores dosis de H2O2 y Fe (II) sobre la variable respuesta porcentaje de remoción de DQO. Previo al tratamiento se caracterizó el agua residual (DQO 10551 mgO2/L, DBO5 850 mgO2/L, fenoles totales 1740mg/L, nitratos 83250 mg/L, sulfatos 104402 mg/L y pH 2.8) cuyas concentraciones superan ampliamente los valores máximos admisibles. La concentración de Fe (II) fue la variable significativa sobre la remoción de la DQO. Con la optimización del proceso, se alcanzó remover un 95.3% de DQO, 67.88% de DBO5, 100% de fenoles totales 91.12% de nitratos y 90.4% de sulfatos, reduciendo la concentración de los parámetros hasta valores de: 495 mgO2/L, 273 mgO2/L, 0.002mg/L, 7312 mg/L y 10031 mg/L, respectivamente, los cuales se encuentran por debajo de los Valores Máximos Admisibles. Se logró incrementar el índice de biodegradabilidad (DBO5/DQO), partiendo de 0.08 de contenido de materia orgánica difícilmente biodegradable, hasta un óptimo de 0.57 de contenido de materia orgánica parcialmente biodegradable. Con lo que se comprueba que el agua residual tratada es menos toxica que el agua residual inicial. Descriptores: Aguas residuales, Foto-Fenton, Valores máximos admisible, biodegradabilidad. Abstract The reduction of the organic matter content in toxic waste water from the seven laboratories at the Universidad Nacional Agraria de la Selva (General Chemistry and Inorganic, Phytochemistry, Soil Analysis, Biochemistry, Microscopy and Animal Health) through the solar photo-Fenton process was researched. To optimize the process, the response surface methods were used, studying the dosing factors of H2O2 and Fe (II) on the variable, percentage of removal response of DQO (acronym in Spanish). Before treatment, the waste water was characterized (DQO 10551 mgO2/L, DBO5 850 mgO2/L, total phenols 1740mg/L, nitrates 83250 mg/L, sulfates 104402 mg/L and pH 2.8); having concentrations which greatly surpassed the maximum allowable values. The concentration of Fe (II) was the significant variable for the removal of the DQO. With the optimization of the process, it was possible to remove a 95.3% of the DQO, 67.88% of the DBO5 (acronym in Spanish), 100% of the total phenols, 91.12% of the nitrates and 90.4% of the sulfates was achieved, reducing the concentration of the parameters to values of: 495 mgO2/L, 273 mgO2/L, 0.002mg/L, 7312 mg/L and 10031 mg/L, respectively, which come in under the maximum allowable values. An increase in the biodegradable index (DBO5/DQO) was achieved, having started with 0.08 difficult biodegradable organic matter content, reaching an optimal 0.57 partially biodegradable organic matter content. With which, it is proven that the treated waste water is less toxic than the initial waste water. Keywords: waste water, Foto-Fenton, Maximum admissible values, biodegradability.

scholarly journals Enhancement of performance and biodegradability kinetics of aerobic-anaerobic sludge digestion

2020 ◽  
Vol 167 ◽  
pp. 01010 ◽  
Author(s):  
Boonchai Wichitsathian ◽  
Jareeya Yimratanabovorn ◽  
Watcharapol Wonglertarak
Keyword(s):  
Organic Matter ◽  
Removal Efficiency ◽  
Aeration Rate ◽  
Anaerobic Sludge ◽  
Sludge Reduction ◽  
Excess Sludge ◽  
Sludge Digestion ◽  
Anaerobic Sludge Digestion ◽  
Aerobic Sludge ◽  
Biodegradable Organic Matter

The excess sludge problem from a wastewater treatment plant is a great concerned due to the high cost of sludge management accounting for about 20% to 50% of the total operating cost. Therefore, sludge reduction is critical. Currently, aerobic and/or anaerobic sludge digestions are widely used in the industries for treating the excess sludge. The objective of this research was to study the effects of aeration rate and temperature on the excess sludge reduction by using the aerobic-anaerobic digestion system in the laboratory. The aeration rates of 1.0, 0.5, and 0.1 volume air per volume slurry per minute (vvm) at the room temperature and the thermophilic temperature (55 ± 2°C) were investigated. The results showed that the highest removal efficiency of aerobic sludge digestion was obtained at the thermophilic temperature and aeration rate of 1.0 vvm. The removal efficiency of organic matter in terms of COD, total solids (TS) and volatile solids (VS) were 34.76%, 33.01% and 43.45%, respectively. Consequently, the highest specific growth rate of microorganisms was 0.39 per hour and the substrate removal rate was 0.55 milligram CODremoved per milligram VSS per hour. Furthermore, slowly biodegradable organic matter was hydrolyzed to readily biodegradable organic matter and inert soluble organic matter. When the sludge effluent from aerobic sludge digestion was feed to the anaerobic sludge digestion, the removal efficiency of organic matter in terms of COD, TS and VS were increased by 25%, 17% and 28%, respectively. Moreover, the obtained methane production rate in the anaerobic sludge digestion was approximate 0.234 m3/kg COD removed.

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