78 research outputs found
Odour and H2S degradation in a full scale biofilter with a mineral based organic coated filter media
[Abstract] In order to minimize the odorous emissions from sludge storage tanks on the waste water treatment plant «Niederrad» of the city of Frankfurt/Main, about 12.000 m3/h of foul air has to be treated. Due to high Hydrogen-Sulphide (H2S) loads, the installed standard biofilter systems failed operation after one year. Thus, one of the existing filter beds was filled with a mineral based organic coated material; the other one was re-filled at the same time with a standard biofilter media to allow a comparative study. In a long term monitoring program from May 2006 to June 2007, both media were compared regarding degradation of H2S and odour. The one-year measurement program revealed that the mineral high performance media performs much better then the standard organic media
IMPACTS OF DIURNALLY EXPOSED SLIME LAYER HYDROGEN SULFIDE CONCENTRATIONS IN SEWER ATMOSPHERE
Hydrogen sulfide (H2S) is a major issue in wastewater collection systems. H2S can cause rapid damage to wastewater infrastructure, affects the publics quality of life through odor issues and is a safety concern for sewer workers. Relatively recent development and introduction of H2S data loggers has shown that H2S concentrations in the sewer headspace demonstrate a diurnal pattern that is not explained by current models. Odor complaints and toxicity are primarily a result of the peak concentration levels and may be more accurately predicted through a better understanding of the diurnal H2S concentration patterns. Biological slime layer grows in the submerged portion of sanitary sewer pipes and is the primary source of H2S in the sewer atmosphere. The diurnal hydraulic cycle common to sanitary sewer systems results in the periodic exposure of a portion of the slime layer. It was hypothesized that the diurnally exposed slime layer impacts the sewer atmosphere concentration of H2S. Utilizing laboratory style tests in a field sewer system showed that the slime layer, when exposed to the sewer atmosphere, will remove H2S. This has not been previously demonstrated and helps explain the diurnal H2S variation in the sewer atmosphere.\u2
Odor Monitoring at Wastewater Treatment Plants
Hydrogen sulfide (H2S) is notable for its toxicity and corrosion is one of the major sources of odor in wastewater treatment plants. Evaluation of existing or potential odor problems requires knowledge of the type of compounds likely to cause such problems and the mechanism of their formation in wastewater systems which is discussed in this paper. For the present study, the East Bank wastewater treatment plant was chosen since it is the largest wastewater treatment facility within Jefferson Parish, Louisiana. To combat the odor problems in this facility, a monitoring program was designed and developed to characterize the severity of the problem. The program involved continuous ambient monitoring followed by careful evaluation of the data obtained from sample collection and analysis. Different instruments were strategically placed within the facility after a hot-spot analysis to determine the major sources of odor generation
Odor Monitoring at Wastewater Treatment Plants
Hydrogen sulfide (H2S) is notable for its toxicity and corrosion is one of the major sources of odor in wastewater treatment plants. Evaluation of existing or potential odor problems requires knowledge of the type of compounds likely to cause such problems and the mechanism of their formation in wastewater systems which is discussed in this paper. For the present study, the East Bank wastewater treatment plant was chosen since it is the largest wastewater treatment facility within Jefferson Parish, Louisiana. To combat the odor problems in this facility, a monitoring program was designed and developed to characterize the severity of the problem. The program involved continuous ambient monitoring followed by careful evaluation of the data obtained from sample collection and analysis. Different instruments were strategically placed within the facility after a hot-spot analysis to determine the major sources of odor generation
Exogenous hydrogen sulfide gas does not induce hypothermia in normoxic mice
Hydrogen sulfide (H2S, 80 ppm) gas in an atmosphere of 17.5% oxygen reportedly induces suspended animation in mice; a state analogous to hibernation that entails hypothermia and hypometabolism. However, exogenous H2S in combination with 17.5% oxygen is able to induce hypoxia, which in itself is a trigger of hypometabolism/hypothermia. Using non-invasive thermographic imaging, we demonstrated that mice exposed to hypoxia (5% oxygen) reduce their body temperature to ambient temperature. In contrast, animals exposed to 80 ppm H2S under normoxic conditions did not exhibit a reduction in body temperature compared to normoxic controls. In conclusion, mice induce hypothermia in response to hypoxia but not H2S gas, which contradicts the reported findings and putative contentions
Reduction of net sulfide production rate by nitrate in wastewater bioreactors. Kinetics and changes in the microbial community
15 páginas, 7 figuras, 5 tablas, 44 referencias.-- [email protected] addition stimulated sulfide oxidation by
increasing the activity of nitrate-reducing sulfide-oxidizing
bacteria (NR-SOB), decreasing the concentration of
dissolved H2S in the water phase and, consequently, its
release to the atmosphere of a pilot-scale anaerobic bioreactor.
The effect of four different concentrations of nitrate
(0.12, 0.24, 0.50, and 1.00 mM) was investigated for a
period of 3 days in relation to sulfide concentration in two
bioreactors set up at Guadalete wastewater treatment plant
(Jerez de la Frontera, Spain). Physicochemical variables were measured in water and air, and the activity of bacteria
implicated in the sulfur and nitrogen cycles was analyzed
in the biofilms and in the water phase of the bioreactors.
Biofilms were a net source of sulfide for the water and gas
phases (7.22±5.3 μmol s−1) in the absence of nitrate dosing.
Addition of nitrate resulted in a quick (within 3 h)
decrease of sulfide both in the water and atmospheric
phases. Sulfide elimination efficiency in the water phase
increased with nitrate concentrations following the
Michaelis–Menten kinetics (Ks=0.63 mM NO3
−). The
end of nitrate addition resulted in a recovery or increase
of initial net sulfide production in about 3 h. Addition of
nitrate increased the activity of NR-SOB and decreased
the activity of sulfate-reducing bacteria. Results confirmed
the role of NR-SOB on hydrogen sulfide consumption
coupled with nitrate reduction and sulfate
recycling, revealing Sulfurimonas denitrificans and
Paracoccus denitrificans as NR-SOB of great importance
in this process.We acknowledge the support of the grants
P06-RNM-01787, P11-RNM-7199, the PAI groups RNM-214
and BIO-288 from Consejería de Innovación, Ciencia y
Empresa, Junta de Andalucía, Spain and CTM2009-10736 from
the Ministerio de Innovación y Ciencia, Spain, which include
cofinancing from FEDER funds. S. Papaspyrou was funded by a
JAE-Doc fellowship (Programa JAE, JAE-Doc109, Spanish National
Research Council) and a Marie Curie ERG action
(NITRICOS, 235005, European Union).Peer reviewe
Odor Monitoring at the New Orleans East Bank Wastewater Treatment Plant
Hydrogen Sulfide is a corrosive, odorous, and hazardous gas that can cause issues for wastewater collection systems and treatment plants. When evaluating hydrogen sulfide concentrations it is important to consider the source, odor causing mechanism, and its level of toxicity. In this study, continuous hydrogen sulfide monitoring was performed for 8 locations within the New Orleans East Bank Wastewater Treatment Plant for a span of 5 months. Hot spots within the plant are located and data analysis is performed based on daily and hourly averages of hydrogen sulfide concentrations. The data was configured to show peak hydrogen sulfide concentrations at specific time intervals throughout the day
Odor Monitoring at the New Orleans East Bank Wastewater Treatment Plant
Hydrogen Sulfide is a corrosive, odorous, and hazardous gas that can cause issues for wastewater collection systems and treatment plants. When evaluating hydrogen sulfide concentrations it is important to consider the source, odor causing mechanism, and its level of toxicity. In this study, continuous hydrogen sulfide monitoring was performed for 8 locations within the New Orleans East Bank Wastewater Treatment Plant for a span of 5 months. Hot spots within the plant are located and data analysis is performed based on daily and hourly averages of hydrogen sulfide concentrations. The data was configured to show peak hydrogen sulfide concentrations at specific time intervals throughout the day
On-line monitoring of methane in sewer air
Methane is a highly potent greenhouse gas and contributes significantly to climate change. Recent studies have shown significant methane production in sewers. The studies conducted so far have relied on manual sampling followed by off-line laboratory-based chromatography analysis. These methods are labor-intensive when measuring methane emissions from a large number of sewers, and do not capture the dynamic variations in methane production. In this study, we investigated the suitability of infrared spectroscopy-based on-line methane sensors for measuring methane in humid and condensing sewer air. Two such sensors were comprehensively tested in the laboratory. Both sensors displayed high linearity (R2 > 0.999), with a detection limit of 0.023% and 0.110% by volume, respectively. Both sensors were robust against ambient temperature variations in the range of 5 to 35°C. While one sensor was robust against humidity variations, the other was found to be significantly affected by humidity. However, the problem was solved by equipping the sensor with a heating unit to increase the sensor surface temperature to 35°C. Field studies at three sites confirmed the performance and accuracy of the sensors when applied to actual sewer conditions, and revealed substantial and highly dynamic methane concentrations in sewer air
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