Where else could UV water purification be used?
I was thinking ships and other marine systems would be able to supplament their purification systems while out at sea. I do not believe they could depend completely on UV as there is no way UV could be used remove the salt and other particles that are in ocean water.
UV, in my opinion, would be easier to use than a solid checmical filtration medium which must be changed out in a time and labor intensive process.
I know there are islands where UV is used to purify the drinking water of individual houses.
Where else or what other environments can you see using UV to purify water?
UV can be used for ultrapure water process for various industries like semiconductor, electronics, pharmacheutical, etc. UV can also be used to treat ballast water in the ship before they can be discharged. More and more home water filter system (point of use) adopt UV as disinfection method combine with activated carbon or membrane inside a water purifer. IN recent years, Uv also being used inside portable drinking water bottle or other comsumer good as a way of disinfection.
UV water purification is a misnomer - it's really about sterilization.
Indeed, the water is not purified as all as there is no separation mechanism going on and dead bacteria, etc.. are all still there, just now biological chemical matter.
That said, UV is already almost everywhere that wants it - we've had it in our home for over a decade.
Research into alternative methods of disinfecting water and wastewater has proven necessary due to the emergence of chlorine-resistant organisms and the disinfection byproducts associated with chlorine use. The use of UV light to inactivate microbial species has proven effective, however; standard UV lamps have proven to be less effective in their ability to inactivate parasites and bacterial endospores in water treatment settings. Pulsed UV (PUV) light may potentially provide a novel alternative to water and wastewater disinfection. Pulsed UV (PUV) is a novel UV irradiation system that is a non-mercury lamp-based alternative to currently used continuous-wave systems for water disinfection. Light emitting diodes (LEDs) in the ultraviolet (UV) range offer a promising alternative for the disinfection of water over the traditional UV lamps. LEDs have many advantages over conventional UV lamps but there are concerns related to the operating life of the LED lamps. It can be operable both in continuous mode (CUV)and pulse (PUV) mode. PUV technology may provide a rapid effective method for the disinfection of water and wastewater.
Advanced oxidation processes (AOPs) can be used to destroy taste and odor-causing compounds in drinking water, which involves use of combined treatment of water with UV and disinfecting agents such as chlorine hydrogen peroxide etc.
UV is used only for disinfection of water from microorganism. It does not filter out unnecessary metal ions from water. Therefore for producing microorganism free filtered drinking water, combination of a proper filtration system along with UV – disinfection system is required.
UV is good technology to inactivate microorganims in the water, however it does not carry residuals, e.g. the secondary contamination may occur. This is the reason why in many facilities UV is followed by one of the forms of chlorination.
As a stand alone technology UV is utilized very rare and for the ground water mainly where microorganics innactivation only is required. The desalination plants on the ships is well established process to desalinte seawater and UV may be part of the entiire system and may not.
UV usually last stage of many water treatment processes for final disinfection. Normally need reasonable quality water standards less than 5NTU and minimal solids to get best results. Average 3-4 log kill rates depending on feed water quality and maintenance. No residuals in network. We market AOP UV units - Advanced Oxidation Process units for food and Pharma industries we can achieve up to 6 log across most water pathogens.
We have found great advantage in performance of RO reducing maintenance and power consumption by placing UV prior to RO unit this reduces biofilm/bio - fouling build up on membranes and increases performance. Really useful in hospitals in their Dialysis units and auroclave areas.
We also have great results for cooling towers, control of Legionella etc using a side stream approach.
In rural areas most of UV units so low on power demand can be easily met by a solar voltaic panel, enabling us to bring safer water to poorer families in remote areas.
We have used in swimming pools enabling us to reduce chlorine levels by 80-90% just for shock loads.
Hope you find this useful, for any specific application, please forward your data.
As a former marine engineer, I am aware of UV usefulness only in prevention/elimination of microbiological contamination of water, for potable water but also for discharge water after the solids and oils have been removed by chemical and mechanical means.
Desalination is a completely separate issue. In my experience, desalinated sea water is primarily used for the replenishment of coolants and other utility use as it is distilled and removed of minerals that could aid corrosion of machine components. Additional chemical treatment is necessary, especially for use in steam boilers, but contamination by microorganisms is irrelevant.
Marine desalinators I worked with inject sea water into a vacuum chamber, with negative pressure dropping the boiling point to around 60 degrees Centigrade or so, heated by the fresh water coolant coil after the exit from the heat-generating machines (think car coolant and radiator). This reuse of thermal energy that would otherwise be emmitted back to the environment makes desalination process on large ships very energy efficient when compared to shore-based plants that must use electicity or fossil fuels for heat generation.
Steam is cooled in the condenser and the remaining brine is pumped back into the environment.
Usually, desalinated water produced in the open ocean is safe for human consumption without additional treatment but not recommended due to the lack of minerals.
The greatest use of UV I've experienced in my career is in decontamination and sterilization of certain consumer products and health supplements, including water used in their production. For example, this is the safest way to sterilize water and compounds used in cosmetics prior to packaging in clean rooms (which are also subjected to UV light during off hours).
UV applications have expanded beyond the drinking, waste, well, and ultrapure waters. In many applications the use of UV is dictated by the regulatory requirements. When fracking was in need UV became a viable option when combined with heavy filtration. Currently the water industry is seeing new regulatory compliance opportunities. The technology is moving in many different directions with a main push towards maximizing performance and regulatory compliance. The ballast water of the ship is one that has been on the radar for 20 years but the regulatory put this in a forward movement in 2015. To the question of where it can be used I would add where (globally we have different requirements and needs) and to what market, the market will drive the technology need to compliance. I believe Dialysis water will be coming up next, that has never been fully developed and this will be a good market for the LED.