Impact of Particles on Ultraviolet Disinfection of Bacteria in Water PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Impact of Particles on Ultraviolet Disinfection of Bacteria in Water PDF full book. Access full book title Impact of Particles on Ultraviolet Disinfection of Bacteria in Water by Raymond Edward Joseph Cantwell. Download full books in PDF and EPUB format.
Author: Raymond Edward Joseph Cantwell
Publisher:
ISBN: 9780494394007
Category :
Languages : en
Pages : 624
Get Book Here
Book Description
When UV light is applied to disinfect drinking water, particles in the water can conceivably protect embedded microorganisms from disinfection. Earlier studies have investigated how turbidity and particles affect light scattering, and particle-associated protection of cultured microorganisms. Little attention has been devoted to the ability of natural particles in water supplies to protect indigenous microorganisms. This thesis focuses on humic-coating of bacteria, the optical properties of particles and particle-related protection of indigenous microorganisms. A bench-scale proof-of-concept study found that both commercial (AHA) and aquatic humic acid (Suwannee River natural organic matter) appears to coat the surface of cultured bacteria hindering the effectiveness of UV disinfection. Both AHA and Suwannee River NOM were found to offer statistically significant (alpha = 0.05) protection of both E. coli and B. subtilis at concentrations of 50 and 120 mg/L. The concentrations of humic matter used in the study (10 to 120 mg/L) exceed those commonly found in surface waters. The bulk LV254 absorbance by particulate material in 10 surface waters was found to be the same order of magnitude as particles from the secondary effluent of a municipal wastewater treatment facility. This implies that since wastewater particles can offer protection to embedded microorganisms from UV light, it is possible for surface water particles to offer similar protection, at least in terms of the optical properties of the particle material. Particle-related protection of indigenous coliforms in untreated surface water from 3 sources (turbidity from 0.8 to 5.4 NTU) was observed with protection attributed to particles> 11 microm. However, despite this protection, at least 2.5-log inactivation of indigenous coliform bacteria was observed in all waters considered. In another untreated surface water (up to 1.3 NTU), no strong evidence of protection of indigenous coliforms or aerobic spores was found. A final objective of this study was to use 14 months of hourly UVT data to evaluate the USEPA's Ultraviolet Disinfection Guidance Manual recommendations for UVT data collection and analysis for design of UV systems. In terms of sampling frequency, both hourly and daily (but not weekly) UVT data collection provided reliable data for UV reactor design.
Author: Raymond Edward Joseph Cantwell
Publisher:
ISBN: 9780494394007
Category :
Languages : en
Pages : 624
Get Book Here
Book Description
When UV light is applied to disinfect drinking water, particles in the water can conceivably protect embedded microorganisms from disinfection. Earlier studies have investigated how turbidity and particles affect light scattering, and particle-associated protection of cultured microorganisms. Little attention has been devoted to the ability of natural particles in water supplies to protect indigenous microorganisms. This thesis focuses on humic-coating of bacteria, the optical properties of particles and particle-related protection of indigenous microorganisms. A bench-scale proof-of-concept study found that both commercial (AHA) and aquatic humic acid (Suwannee River natural organic matter) appears to coat the surface of cultured bacteria hindering the effectiveness of UV disinfection. Both AHA and Suwannee River NOM were found to offer statistically significant (alpha = 0.05) protection of both E. coli and B. subtilis at concentrations of 50 and 120 mg/L. The concentrations of humic matter used in the study (10 to 120 mg/L) exceed those commonly found in surface waters. The bulk LV254 absorbance by particulate material in 10 surface waters was found to be the same order of magnitude as particles from the secondary effluent of a municipal wastewater treatment facility. This implies that since wastewater particles can offer protection to embedded microorganisms from UV light, it is possible for surface water particles to offer similar protection, at least in terms of the optical properties of the particle material. Particle-related protection of indigenous coliforms in untreated surface water from 3 sources (turbidity from 0.8 to 5.4 NTU) was observed with protection attributed to particles> 11 microm. However, despite this protection, at least 2.5-log inactivation of indigenous coliform bacteria was observed in all waters considered. In another untreated surface water (up to 1.3 NTU), no strong evidence of protection of indigenous coliforms or aerobic spores was found. A final objective of this study was to use 14 months of hourly UVT data to evaluate the USEPA's Ultraviolet Disinfection Guidance Manual recommendations for UVT data collection and analysis for design of UV systems. In terms of sampling frequency, both hourly and daily (but not weekly) UVT data collection provided reliable data for UV reactor design.
Author: Michael Richard Templeton
Publisher:
ISBN: 9780494157572
Category :
Languages : en
Pages : 482
Get Book Here
Book Description
Viruses are frequently attached onto or enmeshed within a variety of particles in natural waters and wastewaters, however relatively little is known about the impact of this viral particle-association on water treatment processes. This thesis focuses on the impact of particle-associated viruses on ultraviolet (UV) disinfection, a disinfectant currently gaining widespread popularity in the drinking water industry in North America. Particles smaller than 2 microns (mum) in diameter were shown to be large enough to enmesh and protect bacteriophages MS2 and T4 (model viruses) from UV light. This is smaller than the minimum particle size of 7-10 mum for the shielding of coliform bacteria from the UV disinfection of wastewater reported by earlier studies. In addition, particulate chemical composition, specifically UV-absorbing content such as organic or iron compounds, was a critical factor in the survival of particle-associated bacteriophage exposed to UV light. Particles such as humic acid floc, activated sludge floc, and iron precipitate particles were observed to protect attached phage from UV light. Dual-media filtration, which often precedes UV disinfection in surface water treatment, was shown to be an effective means of reducing the number of particle-associated phage. The breakthrough of particle-associated phage through an anthracite-sand filter was highest during periods of increased particle breakthrough (i.e. filter effluent turbidity> 0.3 NTU), especially at the end of the filter cycle. UV disinfection of phage in the filter effluent was negatively impacted during the end of filter cycle breakthrough conditions in some cases. In addition, it was observed that un-filterable humic acid particles smaller than 0.45 mum and/or humic acid coating of bacteriophage surfaces may have UV-protective effects. The research findings also re-emphasize that viral disinfection studies should account for particle-associated viruses using techniques such as the physico-chemical blending method that was used in this research, since failure to do so can result in significant underestimation of the true virus concentrations. Further, multiple viral surrogates should be used in experimental studies whenever possible, since viruses vary significantly in their sizes, shapes, and surface charges, all of which can influence the adsorption of viruses to particles.
Author: Michael H. Gerardi
Publisher: John Wiley & Sons
ISBN: 0471710423
Category : Science
Languages : en
Pages : 191
Get Book Here
Book Description
A practical guide to wastewater pathogens The fourth volume in Wiley's Wastewater Microbiology series, Wastewater Pathogens offers wastewater personnel a practical guide that is free of overly technical jargon. Designed especially for operators, the text provides straight facts on the biology of treatment as well as appropriate protective measures. Coverage includes: * An overview of relevant history, hazards, and organisms * Viruses, bacteria, and fungi * Protozoa and helminthes * Ectoparasites and rodents * Aerosols, foam, and sludge * Disease transmission and the body's defenses * Removal, inactivation, and destruction of pathogens * Hygiene measures, protective equipment, and immunizations
Author: Hadas Mamane-Gravetz
Publisher:
ISBN:
Category : Bacillus subtilis
Languages : en
Pages : 480
Get Book Here
Book Description
Author: Robert Wayne Emerick
Publisher:
ISBN:
Category :
Languages : en
Pages : 330
Get Book Here
Book Description
Author: Jason Alexander Parker
Publisher:
ISBN:
Category :
Languages : en
Pages : 78
Get Book Here
Book Description
Author: Jason Christensen
Publisher:
ISBN:
Category : Particles
Languages : en
Pages : 312
Get Book Here
Book Description
Author:
Publisher: American Water Works Association
ISBN: 9781583213414
Category : Medical
Languages : en
Pages : 112
Get Book Here
Book Description
This research studied low pressure(LP), low pressure-high-output (LPHO, medium pressure(MP) and pulsed (PUV) UV Systems and their effects on various pathogens. Among the findings were: bacteria is more susceptible to UV light than viruses; some strains of E.coli had different dose responses without explanation; adenovirus serotypes 40 and 41 are highly resistant to UV inactivation and a residual disinfection process is recommended to follow UV disinfection. All details of the study and models are discussed thoroughly.
![An Investigation of UV Disinfection Performance Under the Influence of Turbidity & Particulates for Drinking Water Applications [electronic Resource] PDF](https://books.google.com/books/content/images/frontcover/q6PBjwEACAAJ?fife=w80-h100)
Author: Liu, Guo
Publisher: University of Waterloo
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
UV disinfection performance was investigated under the influence of representative particle sources, including wastewater particles from secondary effluent in a wastewater treatment plant, river particles from surface water, floc particles from coagulated surface water, floc particles from coagulated process water in a drinking water treatment plant, and soil particles from runoff water (planned). Low-pressure (LP) and medium-pressure (MP) UV dose-response of spiked indicator bacteria E. coli was determined using a standard collimated beam apparatus with respect to different particle sources. Significant impacts of wastewater suspended solids (3.13~4.8 NTU) agree with the past studies on UV inactivation in secondary effluents. An average difference (statistical significance level of 5% or a=5%) of the log inactivation was 1.21 for LP dose and 1.18 for MP dose. In river water, the presence of surface water particles (12.0~32.4 NTU) had no influence on UV inactivation at all LP doses. However, when the floc particles were introduced through coagulation and flocculation, an average difference (a=5%) of the log inactivation was 1.25 for LP doses and 1.12 for MP doses in coagulated river water; an average difference (a=5%) of the log inactivation was 1.10 for LP doses in coagulated process water. Chlorination was compared in parallel with UV inactivation in terms of particulate impacts. However, even floc-associated E. coli were too sensitive to carry out the chlorination experiment in the laboratory, indicating that chlorine seems more effective than UV irradiation on inactivation of particle-associated microorganisms. In addition, a comprehensive particle analysis supported the experimental results relevant to this study.
Author: Tatiana Koutchma
Publisher: CRC Press
ISBN: 1000649989
Category : Technology & Engineering
Languages : en
Pages : 360
Get Book Here
Book Description
UV light is one of a number of emerging non-thermal food processing technologies that can be used in a broad range of applications producing food products with longer shelf-life, more safe, and with higher nutritional quality. The new edition of Ultraviolet Light in Food Technology: Principles and Applications will present recent understanding of the fundamentals of UV light along with new applied knowledge that has accumulated during the 7 years since the first edition published in 2009. The new edition of the book will have 11 chapters including 2 new chapters--on chemical destruction with UV light and food plant safety—along with 6 chapters greatly expanded and updated.
