UV radiation inactivates organisms by absorption of the light which causes a photochemical reaction that alters molecular components essential to cell function.
Unlike most disinfectants, ultraviolet (UV) radiation does not inactivate microorganisms by chemical interaction. UV radiation inactivates organisms by absorption of the light which causes a photochemical reaction that alters molecular components essential to cell function. There is ample evidence to conclude that if sufficient dosages of UV energy reach the organisms, UV can disinfect water to whatever degree is required. However, there has been some public health concerns with respect to the overall efficiency of UV to disinfect potable water. Based on the available research literature, it appears that although exceptional for disinfection of small microorganisms such as bacteria and viruses, UV doses required to inactivate larger protozoa such as Giardia and Cryptosporidium are several times higher than for bacteria and virus inactivation. As a result, UV is often considered in concert with ozone and/or hydrogen peroxide to enhance the disinfection effectiveness of UV or for groundwater where Giardia and Cryptosporidium are not expected to occur.
Topics: UV Chemistry (Photochemical) UV radiation UV Disinfection reactions Process variables UV Generation Types of UV lamps and ballasts UV reaction design Microscreening Primary uses and points of application Pathogen/Bacteria/Virus/Protozoa inactivation Disinfection efficiency Inactivation mechanisms Environmental effects Disinfection byproducts UV Dosing Requirements Monitoring and operational considerations Equipment maintenance considerations.Â
Intended Audience: civil, municipal, and environmental engineers, as well as anyone interested in or involved with wastewater treatment. An attendee of this course will gain knowledge about the processes used in domestic wastewater treatment.Â
Publication Source: US Environmental Protection Agency
Dr. Harlan Bengtson is an online PDH course provider of continuing education courses for professional engineers. Dr. Bengtson is a graduate of Iowa State University with B.S. and M.S. degrees and of the University of Colorado with a PhD. He is a licensed Professional Engineer in Missouri. Dr. Bengtson has spent 30 years in engineering education in teaching and administrative positions, including six years as Dean of Engineering at Southern Illinois University Edwardsville. Dr. Harlan H. Bengtson, PE 33 Grainey Drive Glen Carbon, IL 62034 Phone: (618) 406-6892 E-mail: hnkbengtson@yahoo.com PROFESSIONAL PROFILE Dr. Bengtson is a graduate of Iowa State University with B.S. and M.S. degrees and of the University of Colorado with a PhD. He is a licensed Professional Engineer in Missouri. He has spent 30 years in engineering education in teaching and administrative positions, including six years as Dean of Engineering at Southern Illinois University Edwardsville. His areas of expertise are environmental engineering, hydrology and hydraulics, engineering science and renewable energy systems. He has done regular consulting work while holding the academic positions. Prior to entering academia, Dr. Bengtson worked for Minnesota Mining & Manufacturing as a Product Development Engineer and for E. I. duPont deNemours as a Process Development Engineer. Dr. Bengtson has authored numerous publications, presentations and technical reports. He is currently active as a freelance technical writer, author of continuing education courses for Professional Engineers, and is the founder of www.engineeringexceltemplates.com and www.EngineeringExcelSpreadsheets.com, sites with the objective of providing inexpensive, easy to use Excel spreadsheets for a variety of engineering calculations.
