The Japan ozone Association in conjunction with the Water Re-Use Promotion Center, the Japan Water Works Association and the Japan Industrial Water Association held a seminar cover various issues related to ozone in water treatment with a focus on water reuse.
A highlight of the meeting was a tour of a water reclamation projection where over 1 MGD of water is being produced from wastewater. The water is serving various districts of Tokyo for toilet flushing and other applications. this project employs both ozone and micro-filtration membranes to treat the water to a high standard.
While this is a relatively small project, it points to increasing use of wastewater for secondary applications and to the use of ozone water treatment as one of the main components in a water reclamation system.
Temple environmental engineering professor Rominder Suri, Ph.D. is developing new water treatment techniques. With the help of a grant from the National Science Foundation, Suri works in Temple’s Water and Environmental Technology Center searching for alternative water purification methods.
One such method involves the use of Ozone gas and ultraviolet light to destroy foreign contaminates. This method, known as advanced oxidation, has already had a great deal of success in the laboratory and is in the process of being tested on a larger scale.
One of these projects utilizes selective absorbance to purify water. In his lab, Suri has transformed water-soluble glucose molecules into insoluble forms to help remove organic compounds including estrogen from the water. Estrogen hormones have become a problem as they make their way into the water system and have actually led to the feminization of some fish.
Various personal care products and pharmaceuticals used at home eventually find their way into the water system. This holds true for antibacterial soap as well, when it is washed down household sinks into water ways. This could be responsible for increased antibacterial resistance.
The hope is that new treatment methods such as ozone, UV, membranes, and ion exchange will continue to work and be cost-effective when they are introduced on a larger scale.
Virginia American Water conducted a small-scale plant trial that used advanced oxidation, ultraviolet light and hydrogen peroxide to remove the taste and odor-causing compounds in the Appomattox River source water. The plant trial demonstrated that this method efficiently and effectively removed the compounds, even at high levels.
Because of record temperatures of the 2010 summer, microscopic organisms in the Appomattox River had multiplied. When the algae was removed during the water treatment process, they released a nontoxic substance that caused changes in odor and the taste of water.
However, the implementation of such technical modifications would require another rate increase. But in December, the Virginia State Corporation Commission and several commission staff members indicated that with Hopewell’s water continuing to meet all federal and state health standards, there is no regulatory requirement to address the taste and odor problem.
In a customer survey last fall, conducted by a third-party polling firm, only 15 percent of respondents said they would support the engineering solution if the rate increase were $3 to $4 per month, while one-third were opposed to any rate increase. About half of respondents favored a smaller increase of $1 to $3 per month.
Last year, the company slowed down the water treatment process through the newly expanded plant to allow greater treatment time, changed the treatment protocol by feeding additional powdered activated carbon and placed online additional granulated carbon contactors. Th approach was successful in removing the taste and odor problem, although the levels of taste and odor-causing substances were much less than they were in 2010.
A University of Alberta (U of A) research team has found that ozonation can help meat processing plants eliminate the lethal microbial material responsible for Mad Cow disease.
U of A microbiology professors Mike Belosevic and Norm Neumann and engineering professor Mohamed Gamal El-Din demonstrated that infectious proteins, prions, found in the brain matter of cattle can be eradicated from water treated with ozone. Ozone is already used in many food processing plants to decontaminate equipment and reduce bacteria count on fruit, vegetables, meats and fish.
The discovery could have applications in decontaminating wastewater in settings such as slaughterhouse effluents where infected neural material may be present.
Cases of human transmission of infectious prions through surgical equipment have also been documented. The ozone decontamination procedure can potentially be used to sterilize instruments used for neurosurgery, and prevent the transfer of infectious prions during surgical procedures.
Prions have been identified as source of Mad Cow and Chronic Wasting disease in animals. The human variant of this disease is known as Creutzfeld-Jakob disease. Prions are found in the brain and spinal cord tissue of infected animals and are a grave health risk in human and animal health.
Prions are able to destroy and can still be infectious after being incinerated at heats of 850°C. In the wild, soil contaminated by a carcass of a deer that died of Chronic Wasting Disease can remain a source of infection for many years.
The U of A research team’s technique of using water treated with ozone to destroy prions is an improvement on current prion decontamination methods.