Researchers found that solar disinfection coupled with lime juice removed harmful bacteria “significantly” faster than solar disinfection alone
A team of researchers from the Johns Hopkins Bloomberg School of Public Health and the Johns Hopkins School of Medicine found that adding lime juice to water that is treated with a solar disinfection method removed detectable levels of harmful bacteria such as E. coli significantly faster than solar disinfection alone.
The results are featured in the April 2012 issue of American Journal of Tropical Medicine and Hygiene.
As the market for ultraviolet (UV) disinfection systems continues to grow, so does the need for more modern, user-friendly controls. UV systems have come a long way from early versions, which had control features that included a lamp-out circuit and an audible alarm. Modern UV systems include system architecture and displays that are reminiscent of the iPod. Most advances for residential UV systems have come in the form of system controllers instead of reactor designs or lamp technology.
Modern controls make systems easier to use and simpler to service
These NSF/ANSI 55 Class A certified products use a proprietary extended cold-spot lamp design along with an active temperature-controlled cold-spot cooling fan, resulting in improved lamp output maintenance during stagnant hot water conditions. The microprocessor-controlled UV power source has audio/visual alarm indicators to validate lamp operation and an annual lamp change timer. The UV display indicates actual dose in millijoules per square centimeter at rated flow.
Cactus UV purification systems are available for residential and light commercial use, and are engineered to reduce bacteria, cysts and most viruses to safe levels. The X-8 model is available for 8-gpm flow and the X-12 model works for 12-gpm flow. Air-cooled lamps and a standard anti-fouling system allow for a wider and more effective temperature range as well as minimized quartz fouling.
DUV Series UV water disinfection systems are designed for commercial applications from 7 to 25 gpm and feature a stainless steel treatment chamber, visual viewport for lamp operational status, heavy-duty ballast power supply and grounded power cord. The optional UV monitor provides a zero to 100% display of UV lamp intensity.
With its patent-pending secondary window and PTFE probe body, this new UV sensor is designed for long field life and ease of servicing. The single-piece primary PTFE probe body is resistant to leaks, and the removable secondary window enables users to service a fould sensor in minutes with no tools required.
This year’s winning projects for the second annual Top Water Quality Projects program come from all corners of the water treatment marketplace. These winners represent the most innovative and challenging projects submitted by readers to Water Quality Products (WQP) for recognition this year.
To be considered, all projects must have been in the planning or implementation phase in the past 18 months.
Over the years, the public has become more aware of drinking water quality issues. Urban development has placed increased stress on water resources, which in turn has increased the need for cost-effective methods to treat drinking water. This is true regardless of whether the installation is at a single point of use (POU) or at the point of entry (POE) for treating all water used in the home.
Choosing the right treatment option for the water supply
More than ever, sustainable surface and groundwater supplies are essential to communities across North America and around the world. The strains of industry and agriculture on groundwater are noticeable as pressures on water supplies intensify and supply patterns change. The increase in agriculture over vulnerable aquifers, climate change and hydrocarbon production are impacting water quality. Unregulated use or uncontrolled flow of groundwater can cause water quality degradation and conflict between water users.
Small drinking water systems opt for POE UV treatment