scholarly journals Microorganism inactivation by an ozonation step optimized for micropollutant removal from tertiary effluent

2013 ◽  
Vol 68 (2) ◽  
pp. 311-318 ◽  
Author(s):  
H. Schaar ◽  
R. Sommer ◽  
R. Schürhagl ◽  
P. Yillia ◽  
N. Kreuzinger

This paper demonstrates the additional benefit of the microbicidal efficacy of an ozonation plant implemented for micropollutant removal from tertiary effluent. Due to the low amount of viruses and protozoa in the tertiary effluent, bacteriophage MS2 and spores of Bacillus subtilis were dosed as surrogates. At specific ozone consumptions of 0.6 and 0.9 g O3/g dissolved organic carbon (DOC) a 2-log colony forming unit (CFU) reduction was achieved for indigenous Escherichia coli and enterococci, and the limits of the European bathing water directive for the excellent quality of inland waters were met. Higher removal was impeded by the shielding effect of suspended solids in the effluent, which implies the combination of ozonation with a preceding filtration step if higher microbicidal performances are required. The surrogate virus MS2 was reduced by 4–5 log while no significant inactivation was detected for B. subtilis spores. Additionally, the impact of ozonation on the biochemical oxygen demand (BOD) was studied. The BOD5 measurement was not adversely affected despite the reduced concentration of microorganisms after ozonation. The intrinsic increase in BOD5 averaged 15% at 0.6–0.7 g O3/g DOC. The impact of the projected increase on the surface water quality is generally not considered a problem but has to be assessed on a case-by-case approach.

2017 ◽  
Vol 34 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Sofia Bahroun ◽  
Warda Chaib

Abstract In this work, we have conducted a physicochemical study that assesses the impact of agricultural activities and urban domestic wastewater on the surface water quality of the dam reservoir Mexa in the area of El-Taref, which is located in the eastern coastal basin of Constantine. 36 samplings have been conducted for three years (2010, 2011 and 2012), at the rate of one sampling per month on the dam reservoir water; 36 samples have been analysed. The samples taken have been subjected to an in situ measurement of physicochemical parameters (temperature, hydrogen potential, electric conductivity and dissolved oxygen) and laboratory analysis (anions, cations, biological oxygen demand, chemical oxygen demand, organic matter, phosphate, nitrate, nitrite and ammonium). Concentrations of various organic and inorganic pollutants varied from one month to another and from one year to another. From a temporal point of view, the contamination of water of the dam reservoir Mexa varies according to climatic conditions, being generally low during the winter period and high during the low-flow periods. The results obtained reveal that water of the dam reservoir Mexa is fairly contaminated. It is certain that the dam reservoir is subject to pollution of agricultural and urban origin.


2018 ◽  
Vol 52 ◽  
pp. 00037
Author(s):  
Resha Ayu Putri Belinawati ◽  
Tri Edhi Budhi Soesilo ◽  
Herdis Herdiansyah ◽  
Intan Nurul Aini

As one of the 10 most polluted rivers in the world, Citarum river pollution has become the world’s spotlight. The pollution that occurred along the Citarum River in West Java has been the concern of the local government. Pollution not only comes from a plant and household, but also from industries. In this study the authors use descriptive quantitative method, where researchers will describe and compare the existing variables to see the possibilities that arise. Variable used is the number of industries that exist and how the impact against BOD. Biochemical Oxygen Demand (BOD) is a measuring instrument that is widely used to see the quality of oxygen levels in the water. In this paper shows that there is a possibility if BOD increases if the number of industries increases.


2020 ◽  
Vol 10 (1) ◽  
pp. 47-55
Author(s):  
Elena I. VIALKOVA ◽  
Olga V. SIDORENKO ◽  
Ekaterina S. GLUSHENKO

Nowadays there is the problem of the effective treatment of dairy industry plants’ wastewaters. Industrial wastewaters of these plants have high concentrations of organic matters and differ significantly from domestic wastewaters. The method of intensification of dairy wastewaters treatment in Tyumen region, using probiotic «PIP Plus WATER» (Belgium) is considered in this article. The article presents the results of conducted research on the impact of the probiotic on such wastewaters indices as pH, chemical oxygen demand, anionic surfactants, ammonium, nitrites, nitrates and phosphates concentrations. The comparison among different ways of wastewater treatment with probiotics has been made. Based on obtained results technological scheme of local treatment plant of dairy industry plant has been suggested.


Author(s):  
Gilbert K. Gaboutloeloe ◽  
Gugu Molokwe ◽  
Benedict Kayombo

The impact of partially treated wastewater on the water quality of Notwane river stretch in the Gaborone region of Botswana was investigated. Water samples collected at effluent discharge point and three other sampling sites downstream were analyzed for pH, temperature, Biological Oxygen Demand (BOD5), Ammonia-nitrogen (Ammonia-N) and Nitrate-nitrogen (Nitrate-N). Sampling was conducted bi-weekly between February 2013 and April 2013. The ranges of measured parameters were:  pH (7.6-8.5), temperature (22-23ºC), BOD5 (11.2-27.0 mg/l), Ammonia-N (2.4-60.5 mg/l), Nitrate-N (20.6-28.6 mg/l). Analysis of variance, Games-Howel multiple comparisons and Pearson correlation were used to separate variable means. The results signal river non-point pollution due to runoff inflow of organics mainly from land use and domestic waste dumping by nearby dwellings. Temperature, BOD5, and pH range values were all within the Botswana Bureau of Standards (BOBS) limit while the maximum Ammonia-N and Nitrate-N were above BOBS limit by 50.5 mg/l and 6.6 mg/l, respectively. Regulations on indiscriminate waste dumping and discharge standards adherence should be enforced.


2020 ◽  
Vol 61 (5) ◽  
pp. 705-711
Author(s):  
Hyemi Cha ◽  
Kisung Lee ◽  
Moon Seok Park ◽  
Kyoung Min Lee ◽  
Kyeyoung Cho ◽  
...  

ABSTRACT This study evaluated the shielding effect of a newly developed dose-reduction fiber (DRF) made from barium sulfate, in terms of radiation doses delivered to patients’ radiosensitive organs and operator during C-arm fluoroscopy and its impact on the quality of images. A C-arm fluoroscopy unit was placed beside a whole-body phantom. Radiophotoluminescent glass dosimeters were attached to the back and front of the whole-body phantom at 20 cm intervals. Radiation doses were measured without DRF and with it applied to the back (position 1), front (position 2) or both sides (position 3) of the phantom. To investigate the impact of DRF on the quality of fluoroscopic images, step-wedge and modulation transfer function phantoms were used. The absorbed radiation doses to the back of the phantom significantly decreased by 25.3–88.8% after applying DRF to positions 1 and 3. The absorbed radiation doses to the front of the phantom significantly decreased by 55.3–93.6% after applying DRF to positions 2 and 3. The contrast resolution values for each adjacent step area fell in the range 0.0119–0.0209, 0.0128–0.0271, 0.0135–0.0339 and 0.0152–0.0339 without and with DRF applied to positions 1, 2 and 3, respectively. The investigated DRF effectively reduces absorbed radiation doses to patients and operators without decreasing the quality of C-arm fluoroscopic images. Therefore, routine clinical use of the DRF is recommended during the use of C-arm fluoroscopy.


2014 ◽  
Vol 05 (01) ◽  
pp. 60-64 ◽  
Author(s):  
Anthony C. Okoye ◽  
Emma E. Ezenwaji ◽  
Kabir A. Awopeju

Author(s):  
Josiani Cordova de Oliveira ◽  
Kelly Prado Maia ◽  
Nara Linhares Borges de Castro ◽  
Sílvia Maria Alves Corrêa Oliveira

Water quality issues are a growing concern due to the the recent intensification of urbanization and industrialization. This paper evaluates and compares the surface water quality of the ten sub-basins of the Pará River, located in the São Francisco River Basin, Minas Gerais, and evaluates the impact of seasonality and the compliance with the current limits of state legislation. The surface water quality monitoring database of the Institute of Water Management of Minas Gerais (Igam) was used, and 18 parameters were analyzed from a historical series from 2008 to 2016, totaling 16,651 observations. First, the descriptive statistics of the parameters were calculated, considering each sub-basin separately. Then, for the temporal and spatial analysis, the Kruskal-Wallis nonparametric statistical tests were applied, followed by the multiple comparison test, with an alpha level of 5%, due to the asymmetric behavior of the data. Thus, it was possible to compare water quality of the sub-basins in rainy and dry seasons and to identify which parameters were responsible for the greater degradation. In the compliance analysis to the current limits of state legislation, it was identified that all of the sub-basins were out of the specified range for at least one of the evaluated parameters. Finally, the seasonality analysis exposed significant differences in the parameters of dissolved oxygen, turbidity, total suspended solids, total solids and water temperature, where it was shown that there was a worsening of water quality in the rainy season for most sub-basins.


2006 ◽  
Vol 6 (5) ◽  
pp. 59-67 ◽  
Author(s):  
S. Shrestha ◽  
F. Kazama

Different multivariate statistical techniques were used to evaluate temporal and spatial variations of surface water-quality of Fuji river basin using data sets of 8 years monitoring at 13 different sites. The hierarchical cluster analysis grouped thirteen sampling sites into three clusters i.e. relatively less polluted (LP), medium polluted (MP) and highly polluted (HP) sites based on the similarity of water quality characteristics. The principal component analysis/factor analysis indicated that the parameters responsible for water quality variations are mainly related to discharge and temperature (natural), organic pollution (point sources) in LP areas; organic pollution (point sources) and nutrients (non point sources) in MP areas; and organic pollution and nutrients (point sources) in HP areas. The discriminant analysis showed that six water quality parameters (discharge, temperature, dissolved oxygen, biochemical oxygen demand, electrical conductivity and nitrate nitrogen) account for most of the expected temporal variations whereas seven water quality parameters (discharge, temperature, biochemical oxygen demand, pH, electrical conductivity, nitrate nitrogen and ammonical nitrogen) account for most of the expected spatial variations in surface water quality of Fuji river basin.


Geografie ◽  
2018 ◽  
Vol 123 (4) ◽  
pp. 479-505
Author(s):  
Luboš Mrkva ◽  
Bohumír Janský

Despite major investments into the remediation of wastewater, and the reduction of fertilizers, the quality of small river surface water in agricultural and rural regions of Czechia is still very low. The Mastník stream flows through an agricultural area before combining with the Vltava river; a portion of the Mastník stream water inevitably terminates in the Slapy Reservoir. The quality of the water has been analyzed using data from indicator concentrations from both the Vltava River Basin Authority study profiles, and the author’s monitoring profile. The data show that the steps that have been taken – primarily the construction of wastewater treatment plants – have led to a gradual improvement in the surface water quality by some parameters. Presently, a growing concentration of chlorophyll–α and a lack of dissolved oxygen are influencing the final quality of the water. In the case of the Mastník stream, it is particularly necessary to improve the remediation of wastewater from small households, and to reduce the impact of water erosion on agricultural soil.


2013 ◽  
Vol 10 (11) ◽  
pp. 14463-14493
Author(s):  
B. B. Huang ◽  
D. H. Yan ◽  
H. Wang ◽  
B. F. Cheng ◽  
X. H. Cui

Abstract. Under the background of climate change and human's activities, there has been presenting an increase both in the frequency of droughts and the range of their impacts. Droughts may give rise to a series of resources, environmental and ecological effects, i.e. water shortage, water quality deterioration as well as the decrease in the diversity of aquatic organisms. This paper, above all, identifies the impact mechanism of drought on the surface water quality of the basin, and then systematically studies the laws of generation, transfer, transformation and degradation of pollutants during the drought, finding out that the alternating droughts and floods stage is the critical period during which the surface water quality is affected. Secondly, through employing indoor orthogonality experiments, serving drought degree, rainfall intensity and rainfall duration as the main elements and designing various scenario models, the study inspects the effects of various factors on the nitrogen loss in soil as well as the loss of non-point sources pollution and the leaching rate of nitrogen under the different alternating scenarios of drought and flood. It comes to the conclusion that the various factors and the loss of non-point source pollution are positively correlated, and under the alternating scenarios of drought and flood, there is an exacerbation in the loss of ammonium nitrogen and nitrate nitrogen in soil, which generates the transfer and transformation mechanisms of non-point source pollution from a micro level. Finally, by employing the data of Nenjiang river basin, the paper assesses the impacts of drought on the surface water quality from a macro level.


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