Indexes


Book Description




Bacterial Aerosols Resulting from Spray Irrigation with Wastewater


Book Description

Air sampling equipment was selected and adapted for the study of bacterial aerosols generated through land application of treated wastewater by spray irrigation. Preliminary data were obtained on bacteria present in treated and untreated domestic sewage at Army installations. Data were also obtained on survival of enteric bacteria in laboratory aerosols generated from wastewater at various relative humidities. A field study of 3 weeks duration was undertaken to measure aerosol dissemination of bacteria at a wastewater spray irrigation site at Ft. Huachuca, Az, Aerosol densities for the total aerobic bacteria ranged up to 1630 cu. m. at sampling points nearest the aerosol source. Confirmed coliform bacteria represented about 0.5 percent of the total, and of those nearly half were Klebsiella. Densities were greater under conditions of low wind, atmospheric stability and darkness. A mathematical model predicting downwind aerosol densities was developed, based on the dispersion equation of Pasquill and took into account the parameters of the spray equipment used. The model, in conjunction with fluorescein tracer data, was used in deriving an estimate of the fraction of wastewater entering the aerosol state.




Viral and Bacterial Aerosols at a Wastewater Spray Irrigation Site


Book Description

The second phase of a field study to measure microbiological aerosol disemination by the spray irrigation mode of land wastewater application was conducted at Ft. Huachuca, AZ. Chlorinated and unchlorinated secondarily treated wastewaters were sprayed in periods of high and low sunlight intensity, and bacterial and virus aerosols were sampled. Predictions of long distance migration and aerosol dispersal of total aerobic bacteria and enteric virus (utilizing seeded coliphage f2 as a model), were emphasized.







Methods For Recovering Viruses From The Environment


Book Description

This book argues, that without methods, there can be no research. Effective research requires effective methods, not always easy to come by. The development of methods in environmental virology became a focus of growing interest about two decades ago. Progress has been significant since that time in pure experimental systems, where there are no interferences, consistent high recoveries of viruses from environmental waters has been achievable for some time. In the natural environment, however, in relatively clean waters, substances such as humic and fulvic acids interfere with viral recoveries and average recovery rates probably do not reach 20%. With sewage sludges and shellfish, recoveries are undoubtedly much lower. Yet, even relatively low viral recovery rates have made possible the detection of viral hazards in drinking waters. The hazards that exist are undoubtedly much greater than those demonstrated with the relatively inefficient methods inefficient methods developed thus far. Improving methods, as they are developed in the years to come, will undoubtedly bring the true extent of the hazards into better perspective.




Formula Handbook for Environmental Engineers and Scientists


Book Description

Dieses nützliche Handbuch umfaßt über 200 Formeln, die von Umweltingenieuren für Problemlösungen im Bereich biologischer und biochemischer Prozesse in natürlichen und künstlich angelegten Systemen eingesetzt werden. Jeder Problemeintrag erhält eine Definition, eine Formel, Zahlenwerte, die in der Literatur genannt werden, Verweise und entsprechende Tabellen und Diagramme. Umrechnungstabellen finden sich im Anhang. (10/97)




Natural Systems for Waste Management and Treatment


Book Description

MANAGE WASTE AT LOWER COST WITH EMERGING NATURAL SYSTEMS Biologically-based waste management systems are emerging as a more reliable, less costly alternative to conventional energy-intensive mechanical process. If you're involved in planning, designing, building, upgrading or operating waste management facilities, Natural Systems for Waste Management and Treatment, Second Edition, by Sherwood C. Reed, Ronald W. Crites, and E. Joe Middlebrooks, can help you quickly evaluate and adopt one or more of these innovative technologies. Complete with performance data plus easy-to-follow design procedures (with example), it gives you a thorough working backgroud in: Wastewater stabilization ponds; Aquatic treatment systems; Feasibility assessment; Land treatment systems; Wetland systems; Site selection; Planning; Sludge management and treatment; On-site wastewater management; Much more.