Case Study of Particle-Related UV Shielding of Microorganisms When Disinfecting Unfiltered Surface Water

2010 ◽  
Vol 45 (3) ◽  
pp. 343-351 ◽  
Author(s):  
Raymond E. Cantwell ◽  
Ron Hofmann ◽  
Jennie L. Rand ◽  
Patrick M. Devine ◽  
Monique VanderMarck
Keyword(s):  
Surface Water ◽  
Uv Light ◽  
Pilot Scale ◽  
Uv Disinfection ◽  
Particle Count ◽  
Uv Reactor ◽  
Before And After ◽  
Log Linear ◽  
Uv Lamps

Abstract The goal of this case study was to provide pilot-scale information about the ability of ultraviolet (UV) light to disinfect unfiltered surface water. A pilot-scale (0.25 L/s) UV reactor with low-pressure UV lamps was installed on raw water entering an aqueduct from the Pardee Reservoir at the East Bay Municipal District, California. A pilot monitoring system also collected hourly particle count (2 to 100 m), turbidity, and ultraviolet transmittance (UVT) measurements for 14 months. Grab microbial samples were collected and analyzed for indigenous total coliforms and total aerobic spores (TAS) both before and after UV disinfection, to correlate survival of the organisms across the UV reactor to water quality characteristics. Concentrations of indigenous coliforms and TAS ranged up to 163 and 1,383 per 100 mL respectively, before UV exposure. The data showed that the ability of UV to disinfect coliforms was essentially unaffected by the presence of particles (up to 703>10 m per mL and 1.3 nephelometric turbidity unit [NTU]) in the unfiltered surface water. In 13 of 14 samples, no coliforms were detected in the UV treated water. Log-linear inactivation of TAS up to 2.5-log suggests that at least 99.6% of the TAS were not protected from UV disinfection by particles.

scholarly journals How effective is river restoration in re-establishing groundwater–surface water interactions? – A case study

2015 ◽  
Vol 19 (6) ◽  
pp. 2663-2672 ◽  
Author(s):  
A.-M. Kurth ◽  
C. Weber ◽  
M. Schirmer
Keyword(s):  
Surface Water ◽  
River Restoration ◽  
Morphological Changes ◽  
Cost Effective ◽  
Urban Stream ◽  
Distributed Temperature Sensing ◽  
River Bed ◽  
Before And After ◽  
Restoration Measures

Abstract. In this study, we investigated whether river restoration was successful in re-establishing groundwater–surface water interactions in a degraded urban stream. Restoration measures included morphological changes to the river bed, such as the installation of gravel islands and spur dykes, as well as the planting of site-specific riparian vegetation. Standard distributed temperature sensing (DTS) and novel active and passive DTS approaches were employed to study groundwater–surface water interactions in two reference streams and an experimental reach of an urban stream before and after its restoration. Radon-222 analyses were utilized to validate the losing stream conditions of the urban stream in the experimental reach. Our results indicated that river restoration at the study site was indeed successful in increasing groundwater–surface water interactions. Increased surface water downwelling occurred locally at the tip of a gravel island created during river restoration. Hence, the installation of in-stream structures increased the vertical connectivity and thus groundwater–surface water interactions. With the methods presented in this publication, it would be possible to routinely investigate the success of river restorations in re-establishing vertical connectivity, thereby gaining insight into the effectiveness of specific restoration measures. This, in turn, would enable the optimization of future river restoration projects, rendering them more cost-effective and successful.

Reduced isolation room turnover time using Lean methodology

2019 ◽  
Vol 40 (10) ◽  
pp. 1151-1156 ◽  
Author(s):  
Andrea L. Ankrum ◽  
Smriti Neogi ◽  
Molynda A. Morckel ◽  
Adam W. Wilhite ◽  
Zhaoyan Li ◽  
...  
Keyword(s):  
Uv Light ◽  
Patient Flow ◽  
Wait Time ◽  
Turnover Time ◽  
Value Stream Mapping ◽  
Uv Disinfection ◽  
Healthcare Team ◽  
Start Time ◽  
Isolation Room ◽  
Before And After

AbstractObjective:To prevent environmental transmission of pathogens, hospital rooms housing patients on transmission-based precautions are cleaned extensively and disinfected with ultraviolet (UV) light. To do so consistently requires time and coordination, and these procedures must avoid patient flow delays and associated safety risks. We sought to improve room turnover efficiency to allow for UV disinfection.Design:A 60-day quality improvement and implementation project.Setting:A quaternary academic pediatric referral facility.Interventions:A multidisciplinary healthcare team participated in a 60-day before-and-after trial that followed the Toyota Production System Lean methodology. We used value-stream mapping and manual time studies to identify areas for improvement. Areas addressed included room breakdown, room cleaning, and wait time between cleaning and disinfection. Room turnover was measured as the time in minutes from a discharged patient exiting an isolation room to UV disinfection completion. Impact was measured using postintervention manual time studies.Results:Median room turnover decreased from 130 minutes (range, 93–294 minutes) to 65 minutes (range, 48–95 minutes; P < .0001). Other outcomes included decreased median time between room breakdown to cleaning start time (from 10 to 3 minutes; P = .004), room cleaning complete to UV disinfection start (from 36 to 8 minutes; P < .0001), and the duration of room cleaning and curtain changing (from 57 to 37 minutes; P < .0001).Conclusion:We decreased room turnover time by half in 60 days by decreasing times between and during routine tasks. Utilizing Lean methodology and manual time study can help teams understand and improve hospital processes and systems.

scholarly journals How effective is river restoration in re-establishing groundwater – surface water interactions? – A case study

2015 ◽  
Vol 12 (1) ◽  
pp. 1093-1118
Author(s):  
A.-M. Kurth ◽  
C. Weber ◽  
M. Schirmer
Keyword(s):  
Surface Water ◽  
River Restoration ◽  
Cost Effective ◽  
Urban Stream ◽  
Distributed Temperature Sensing ◽  
Before And After ◽  
Restoration Measures ◽  
Insight Into ◽  
Gaining Insight

Abstract. In this study we investigated whether river restoration was successful in re-establishing vertical connectivity and, thereby, groundwater-surface water interactions, in a degraded urban stream. Well-tried passive Distributed Temperature Sensing (DTS) and novel active and passive DTS approaches were employed to study groundwater-surface water interactions in an experimental reach of an urban stream before and after its restoration and in two (near-) natural reference streams. Results were validated with Radon-222 analyses. Our results indicated that river restoration at the study site was indeed successful in increasing groundwater-surface water interactions. Increased surface water downwelling occurred locally at the tip of a gravel island created during river restoration. Hence, the installation of in-stream structures increased the vertical connectivity and thus groundwater-surface water interactions. With the methods presented in this publication it would be possible to routinely investigate the success of river restorations in re-establishing vertical connectivity, thereby gaining insight into the effectiveness of specific restoration measures. This, in turn, would enable the optimization of future river restoration projects, rendering them more cost-effective and successful.

scholarly journals Monitoring of waters status on the area of the waste landfill – case study Piškornica

2019 ◽  
Vol 6 (2) ◽  
pp. 49-58
Author(s):  
Jasna Nemčić-Jurec
Keyword(s):  
Water Management ◽  
Surface Water ◽  
Numerical Model ◽  
Groundwater Flow ◽  
Groundwater Pollution ◽  
Waste Landfill ◽  
Significant Difference ◽  
Before And After ◽  
Harmful Effects

The remediation of the municipal waste landfill reduces the harmful effects of inadequately disposed waste in the environment and reduce the risks on human health. The aim of this paper is to evaluate the efficiency of the remediation (2005 to 2012) of waste landfill of Piškornica. Groundwater from piezometers (P2, P3, P4 and P5) at Piškornica and surface water from the Gliboki stream (upstream and downstream) were analyzed, before and after the remediation. The results of the analyzed parameters (KPK, BPK5, electroconductivity, iron) showed significant decrease in values (p &lt;0.05) and up to 82% (BPK5 in P5) after remediation. The most significant decrease in the value of the indicators was determined in the P5, which is nearest and downstream from the landfill body. Significant difference (p &lt;0.05) was not found at the upstream and downstream locations of the Gliboki stream basin before and after remediation. The numerical model of the groundwater flow shows that groundwater pollution will not occur even in the worst scenario (the largest possible pumping of 420 l/s) of the current capacity of the Ivanščak source. The results contributed to decisions on water management and further monitoring of water plans on landfill area.

Photocatalytic thin film cascade reactor for treatment of organic compounds in wastewater

2001 ◽  
Vol 44 (5) ◽  
pp. 187-195 ◽  
Author(s):  
A.H.C. Chan ◽  
J.F. Porter ◽  
J.P. Barford ◽  
C.K. Chan
Keyword(s):  
Benzoic Acid ◽  
Photocatalytic Oxidation ◽  
Uv Light ◽  
Degradation Process ◽  
Pilot Scale ◽  
Steel Plates ◽  
Solution Temperature ◽  
Photocatalytic Process ◽  
Photolytic Degradation ◽  
Uv Lamps

The photocatalytic oxidation of benzoic acid was investigated in a pilot scale-cascade photoreactor. The photoreactor consists of an array of UV lamps (40 W, 365 nm) illuminating a cascade of three inclined 316 stainless steel plates, on which titanium dioxide (TiO2) was immobilized by electrophoretic deposition. The percentage removal of total organic carbon (TOC) of liquid samples was determined. The photocatalytic process was affected by several operating parameters. Increasing the solution temperature was found to reduce the dissolved oxygen (DO) level and to decrease the rate of the degradation process. The Langmuir-Hinshelwood equation was found to be accurate for modeling the degradation of benzoic acid with initial concentrations of 50 ppm, 75 ppm and 100 ppm. The rate of removal of TOC was positively affected by UV light intensity, but appeared to be independent of solution flowrate in the range examined. Control experiments confirmed that the effects of adsorption of the solute onto the TiO2 catalysts and photolytic degradation were negligible.

scholarly journals Pengaruh Jumlah Sinar Ultra Violet Terhadap Penurunan Kandungan Bahan Organik di Dalam Pengolahan Air Gambut yang Dilanjutkan dengan Saringan Pasir Lambat

2019 ◽  
Vol 1 (2) ◽  
pp. 21-24
Author(s):  
M Ma’arij Harfadli
Keyword(s):  
Uv Irradiation ◽  
Uv Light ◽  
Peat Soil ◽  
Ultra Violet ◽  
Water Source ◽  
Raw Water ◽  
Optimum Time ◽  
Organic Matters ◽  
Uv Reactor ◽  
Uv Lamps

One of the areas with a complicated drinking are the areas with peat soil. This area has a lot water source, one of treatments for peat water is variation in using the UV light for peat water processing.There is reactors in this research: the UV reactor is made of glass with a 6 liters of reactor volume. The reactor contains 15 watts of 3 ultra violet UV lamps. Processing raw water is done in batch and reactor continuously. The wavelength is 370 nm which initial absorbance value of 2.045. The optimum time occurs 30 minutes in 3 lamp of UV irradiation with the elimination of organic matters of 36 mg / l.73%.

Case study of treatment of waste water for 17α-ethinylestradiol and microorganisms with UV and photocatalysis in an on-going process of introducing AOP techniques in the Danish water sector

2012 ◽  
Vol 7 (4) ◽  
Author(s):  
H. T. Madsen ◽  
E. G. Søgaard
Keyword(s):  
Waste Water ◽  
Uv Light ◽  
Current System ◽  
Endocrine Disrupting Chemicals ◽  
Optimal Solution ◽  
Use Of Data ◽  
Endocrine Disrupting ◽  
Uv Lamps ◽  
Danish Water

Failure to obtain a sufficient disinfection of waste water, initiated an investigation of the use of UV light and photocatalysis with TiO2 for treating the waste water. Furthermore, the ability of such a system to degrade endocrine disrupting chemicals was investigated through experiments with the estrogen 17α-ethinylestradiol (EE2). This study found LP UV lamps to be the optimal solution for disinfection, while photocatalysis with TiO2 was found to be the best method for removal of EE2. The experiments were carried out in a mobile test unit with solution volumes of 30 L. By use of data from the real UV system, the effect found in the experiments were extrapolated and used to evaluate the efficiency of the current system.

scholarly journals Presence and Reduction of Anthropogenic Substances with UV Light and Oxidizing Disinfectants in Wastewater—A Case Study at Kuopio, Finland

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 360
Author(s):  
Jenni Ikonen ◽  
Ilpo Nuutinen ◽  
Marjo Niittynen ◽  
Anna-Maria Hokajärvi ◽  
Tarja Pitkänen ◽  
...  
Keyword(s):  
Aquatic Ecosystems ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Uv Light ◽  
Wastewater Effluent ◽  
Uv Disinfection ◽  
No Removal ◽  
Disinfection Methods ◽  
Harmful Effects

Anthropogenic substances are a major concern due to their potential harmful effects towards aquatic ecosystems. Because wastewater treatment plants (WWTPs) are not designed to remove these substances from wastewater, a part of the anthropogenic substances enter nature via WWTP discharges. During the spring 2019, the occurrence of anthropogenic substances in the municipal wastewater effluent in Kuopio, Finland, was analysed. Furthermore, the capacity of selected disinfection methods to reduce these substances from wastewater was tested. The disinfection methods were ozonation (760 mL min−1) with an OxTube hermetic dissolution method (1), the combined usage of peracetic acid (PAA) (<5 mg L−1) and ultraviolet (UV) disinfection (12 mJ/cm2) (2), and the combined usage of hydrogen peroxide (H2O2) (<10 mg L−1) and UV disinfection (12 mJ/cm2) (3). The substances found at the concentrations over 1 µg L−1 in effluent (N = 3) were cetirizine (5.2 ± 1.3 µg L−1), benzotriazole (BZT) (2.1 ± 0.98 µg L−1), hydrochlorothiazide (1.7 ± 0.2 µg L−1), furosemide (1.6 ± 0.2 µg L−1), lamotrigine (1.5 ± 0.06 µg L−1), diclofenac (DCF) (1.4 ± 0.2 µg L−1), venlafaxine (1.0 ± 0.13 µg L−1) and losartan (0.9 ± 0.2 µg L−1). The reduction (%) with different methods (1, 2, 3) were: cetirizine (99.9, 5.0, NR = no removal), benzotriazole (67.9, NR, NR), hydrochlorothiazide (91.1, 5.9, NR), furosemide (99.7, 5.9, NR), lamotrigine (46.4, NR, 6.7), diclofenac (99.7, 7.1, 16.7), venlafaxine (91.3, NR, 1.1), losartan (99.6, 13.8, NR). Further research concerning the tested disinfection methods is needed in order to fully elucidate their potential for removing anthropogenic substances from purified wastewater.

Sorbitol enhances the physicochemical stability of B12 vitamers

2020 ◽  
Vol 90 (5-6) ◽  
pp. 439-447 ◽  
Author(s):  
Andrew Hadinata Lie ◽  
Maria V Chandra-Hioe ◽  
Jayashree Arcot
Keyword(s):  
Ascorbic Acid ◽  
Uv Light ◽  
Heat Exposure ◽  
Water Soluble ◽  
Uv Exposure ◽  
Physicochemical Stability ◽  
Before And After ◽  
The Stability

Abstract. The stability of B12 vitamers is affected by interaction with other water-soluble vitamins, UV light, heat, and pH. This study compared the degradation losses in cyanocobalamin, hydroxocobalamin and methylcobalamin due to the physicochemical exposure before and after the addition of sorbitol. The degradation losses of cyanocobalamin in the presence of increasing concentrations of thiamin and niacin ranged between 6%-13% and added sorbitol significantly prevented the loss of cyanocobalamin (p<0.05). Hydroxocobalamin and methylcobalamin exhibited degradation losses ranging from 24%–26% and 48%–76%, respectively; added sorbitol significantly minimised the loss to 10% and 20%, respectively (p < 0.05). Methylcobalamin was the most susceptible to degradation when co-existing with ascorbic acid, followed by hydroxocobalamin and cyanocobalamin. The presence of ascorbic acid caused the greatest degradation loss in methylcobalamin (70%-76%), which was minimised to 16% with added sorbitol (p < 0.05). Heat exposure (100 °C, 60 minutes) caused a greater loss of cyanocobalamin (38%) than UV exposure (4%). However, degradation losses in hydroxocobalamin and methylcobalamin due to UV and heat exposures were comparable (>30%). At pH 3, methylcobalamin was the most unstable showing 79% degradation loss, which was down to 12% after sorbitol was added (p < 0.05). The losses of cyanocobalamin at pH 3 and pH 9 (~15%) were prevented by adding sorbitol. Addition of sorbitol to hydroxocobalamin at pH 3 and pH 9 reduced the loss by only 6%. The results showed that cyanocobalamin was the most stable, followed by hydroxocobalamin and methylcobalamin. Added sorbitol was sufficient to significantly enhance the stability of cobalamins against degradative agents and conditions.

The Influence of Attitudes, Subjective, Norms, and Behavior Controls on Intention to Choose Islamic Banks With Islamic Religiosity as a Moderating Variable (Case Study at Bri Syariah Purwokerto Customers)

2018 ◽  
Vol 2 (1) ◽  
Author(s):  
Akhmad Khoyrun Najakh ◽  
Dwiwiyati Astogini ◽  
Sri Martini
Keyword(s):  
Behavioral Control ◽  
Sampling Technique ◽  
Subjective Norm ◽  
Subjective Norms ◽  
Islamic Banks ◽  
Control Behavior ◽  
Before And After ◽  
And Behavior ◽  
Number Of Customers

The purpose of this study was to analyze the influence of attitudes on the intention to choose Islamic banks, to analyze the effect of subjective norm on the intention to choose Islamic banks. to analyze the effect of the control behavior of the intention to choose the Islamic banks, to analyze the moderating influence of religiosity on the relationship attitudes, subjective norms and behavioral control of the intention to choose the Islamic banks . The method used is a survey with a sampling technique used purposive sampling with a sample size of this study was 100 respondents . Further analysis tools used in this study is multiple regression analysis using SPSS 16.0 software . Based on this study it can be concluded that the attitude does not affect to the intention of choose Bank BRISyariah. Subjective norm positive effect on intention choose Bank BRISyariah. Control behavior does not affect to the intention choose Bank BRISyariah. Relationship between Attitudes, Subjective Norms and Behavior Control with the intention to select Bank BRISyariah not moderated by religiosity.Based on these conclusions can be said that the Bank BRISyariah should improve understanding related to the subjective norm in order to increase the number of customers who use the services of Islamic Banking . Further research is recommended in order to follow up and develop this research to further explore the independent and dependent variables continued before and after behavioral intention or intention to perform a specific action .

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