What is UV light
UV-A (315 to 400 nm): Long wave UV, also known as “black light “, the major type of UV in sunlight, responsible for skin tanning, generally not harmful, used in medicine to treat certain skin disorders.
How does UV light destroy microorganisms
Ultraviolet rays with wavelengths shorter than 300 nm are extremely effective in killing microorganisms. The most effective sterilizing range for UV is within the C bandwidth (UVC). This range is called the germicidal bandwidth. UVC has been used in hospitals for decades to sterilize surgical instruments, water, and the air in operating rooms. Many food and drug companies use germicidal lamps to disinfect various types of products and their containers.
All living organisms contain DNA (deoxyribonucleic acid). DNA provides the mechanism for all functions needed to sustain life. The UV light from 200 to 300 nm is easy to be absorbed by the cells, and the 253.7 nm has the strongest disinfection ability. The UV light penetrates the outer cell membranes of microorganisms, passes through the cell body, reaches the DNA and permanently alters the genetic material. The microorganisms are thereby destroyed in a non-chemical manner.
UV disinfection is a purely physical process. Micro-organisms such as bacteria, viruses, yeast, etc. that are exposed to the effective UV-C radiation are inactivated within seconds. It does not add anything to the water, such as undesirable color, odor, taste or flavor, nor does it generate harmful byproducts. It is fast, efficient, effective, economical and environmentally friendly.
The following are incident energies of germicidal ultraviolet radiation at 254 nanometers necessary to inhibit colony formation in microorganisms (90%) and for complete destruction
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| Bacillus paratyphusus | 3,200 | 6,100 |
| Bacillus subtilis spores | 11,600 | 22,000 |
| Bacillus subtilis | 5,800 | 11,000 |
| Clostridium tetani | 3,370 | 6,510 |
| Corynebacterium diphtheriae | 2,140 | 4,100 |
| Ebertelia typhosa | 3,000 | 6,600 |
| Escherichia coli | 3,150 | 6,000 |
| Leptospiracanicola – infectious Jaundice | 6,050 | 12,300 |
| Microccocus candidus | 1,000 | 15,400 |
| Microccocus sphaeroides | 6,200 | 10,000 |
| Mycobacterium tuberculosis | 4,400 | 8,000 |
| Neisseria catarrhalis | 3,000 | 6,600 |
| Phytomonas tumefaciens | 5,500 | 10,500 |
| Proteus vulgaris | 3,500 | 6,600 |
| Pseudomonas aeruginosa | 4,000 | 7,600 |
| Pseudomonas fluorescens | 3,200 | 6,100 |
| Salmonella enteritidis | 2,150 | 4,100 |
| Salmonela paratyphi – Enteric fever | 8,000 | 15,200 |
| Salmonella typhosa – Typhoid fever | 19,700 | 26,400 |
| Salmonella typhimurium | 2,420 | 6,160 |
| Sarcina lutea | 2,200 | 4,200 |
| Serratia marcescens | 1,700 | 3,400 |
| Shigella dyseteriae – Dysentery | 1,680 | 3,400 |
| Shigella flexneri – Dysentery | 4,400 | 6,160 |
| Shigella paradysenteriae | 1,840 | 5,720 |
| Spirillum rubrum | 2,600 | 6,600 |
| Staphylococcus albus | 2,160 | 5,500 |
| Staphylococcus aerius | 6,150 | 8,800 |
| Staphylococcus hemolyticus | 2,000 | 3,800 |
| Staphylococcus lactis | 6,150 | 8,800 |
| Streptococcus viridans | 2,000 | 3,800 |
| Vibrio comma – Cholera | 3,375; | 6,500 |
| Organisms: | ||
| Energy dosage of Ultraviolet radiation in цW/cm2 needed for kill factor | ||
| Molds | 90% | 100% |
| Aspergillius flavus | 4,520 | 8,700 |
| Aspergillius glaucus | 24,320 | 46,200 |
| Aspergillius niger | 2,730 | 5,200 |
| Mucor racemosus A | 1,300 | 2,500 |
| Mucor racemosus B | 3,200 | 6,100 |
| Oospora lactis | 11,600 | 22,000 |
| Penicillium expansum | 5,800 | 5,800 |
| Penicillium roqueforti | 3,370 | 6,510 |
| Penicillium digitatum | 2,140 | 4,100 |
| Rhisopus nigricans | 3,000 | 6,600 |
| Protozoa | 90% | 100% |
| Chlorella Vulgaris | 6,050 | 12,300 |
| Nematode Eggs | 1,000 | 15,400 |
| Paramecium | 6,200 | 10,000 |
| Virus | 90% | 100% |
| Bacteriopfage – E. Coli | 3,000 | 6,600 |
| Infectious Hepatitis | 5,500 | 10,500 |
| Influenza | 3,500 | 6,600 |
| Poliovirus – Poliomyelitis | 4,000 | 7,600 |
| Tobacco mosaic | 3,200 | 6,100 |
| Yeast | 90% | 100% |
| Brewers yeast | 8,000 | 15,200 |
| Common yeast cake | 19,700 | 26,400 |
| Saccharomyces carevisiae | 2,420 | 6,160 |
| Saccharomyces ellipsoideus | 2,200 | 4,200 |
| Saccharomyces spores | 1,700 | 3,400 |
UV applications
Ultraviolet technology can be used for water disinfection as well other liquids and air. Ultraviolet (UV) light represents a powerful technology that has been successfully deployed in several diverse industries such as pharmaceutical, semiconductor, power generation, food and beverage, cosmetics, aquaculture, and healthcare for several decades. While the most common application of UV radiation in water treatment is disinfection, its powerful energy can also be harnessed for other applications such as TOC (Total Oxidizable Carbon) reduction, ozone destruction, and chlorine/ chloramines destruction.
Two different UV wavelengths are employed in water treatment, the 254 nm and the 185 nm. The 254 nm (1 nm=10-9 m=10) UV light (also called the “germicidal light” because of its unique ability to destroy microorganism) is employed in disinfection and ozone destruction applications. It penetrates the outer cell-wall of the microorganism, passes through the cell-body, reaches the DNA (deoxyribonucleic acid) and disrupts the genetic material. The microorganisms are thereby destroyed in a non-chemical manner. The 254 nm UV light can also destroy residual ozone present in a water stream. The 185 nm UV light, utilized in TOC reduction application, decomposes the organic molecules. The 185 nm light carries more energy than the 254 nm light. It is also capable of cleaving the water molecule to yield hydroxyl (OH·) free radicals.
The mechanism of oxidation of the organic species by UV radiation is a complex one. The centerpiece of the reaction is the OH free-radical. It plays a pivotal role in the oxidation reaction. The OH radicals are responsible for oxidizing the hydrocarbon molecules quantified as TOC into carbon dioxide and water molecules. The OH radical is one of the most powerful oxidizing agents known to science.
Using standardized and client-specific systems, Aqua Lightech offers solutions for drinking water, process water, purified water and sewage, as well as for special applications.
UV advantages
Boil water
- Beyond the inconvenience they cause, such advisories are a clear warning that the clean water we’ve taken for granted is becoming a scarce resource.
Chemical Disinfection
- Not effective against Cryptosporidium and Giardia.
Water Filtration
- Not effective against bacteria, viruses and other harmful microorganisms
Reverse Osmosis (R/O)
- Not recommended for use with water that is microbiologically unsafe or of unknown quality.
Boil water
Beyond the inconvenience they cause, such advisories are a clear warning that the clean water we’ve taken for granted is becoming a scarce resource.
Chemical Disinfection
Not effective against Cryptosporidium and Giardia.
Water Filtration
Not effective against bacteria, viruses and other harmful microorganisms
Reverse Osmosis (R/O)
Not recommended for use with water that is microbiologically unsafe or of unknown quality.
Ultraviolet (UV) Light
Highly Effective Aqua Best UV systems treat the water for the whole time, eliminating 99.99% of bacteria and viruses including chlorine resistant cysts that are not tested for in routine water tests.
Ultraviolet (UV) light treatment is a widely recognized and proven method of disinfection of water and has several advantages over other disinfection methods. It is fast, efficient, effective, economical and environmentally-friendly.
UV disinfection is a purely physical process. Micro-organisms such as bacteria, viruses, yeast, etc. that are exposed to the effective UV-C radiation are inactivated within seconds. The advantages are as follows:
- No chemicals added
- No environmental problems
- The water retains its natural flavor and smell
- No by-products that might endanger health
- No corrosion problems
- No reaction tanks or secondary pumps
- Micro-organisms inactivated within seconds
- A technology tried and tested in thousands of installations
- The process requires little maintenance and is easy to handle
- Minimum operating costs
- Maximum operating safety
- Modular system for adaptability
Factors affecting UV Reduction Levels
- SANITIZATION
- Defined as 50 – 99% reduction (2-log)
- DISINFECTION
- Defined as 99.99% reduction (4-log)
- STERILIZATION
- Defined as 99.9999% reduction (6-log)
- DOSAGE is the product of Intensity & Time
- DOSAGE
- = INTENSITY X TIME
- = microW/cm2 X time
- = microWsec/cm2
- Note: 1000 microWsec/cm2 = 1 mJ/cm2
Factors Affecting UV
- UV can only be effective if it is absorbed by the target:
- UV absorption in water is almost entirely caused by dissolved substances. Certain organic substances such as humic or fumic acids (tannins), and certain inorganic substances such as iron and manganese absorb UV.
- Suspended solids shield microorganism and need filtration.
- Hardness causes the formation of scale on the quartz sleeve surface and therefore prevents transmissibility.
- Iron causes the staining of the quartz sleeve thereby impeding UV transmission
- Lamp operating temperature levels is an important factor. The optimum being 40oC. The increase or decrease of temperature will affect UV energy levels. Quartz sleeves will minimize temperature fluctuations.
- Good flow rate design does take into account energy level fluctuations.
Water Quality Effects
- ABSORPTION
– This varies according to the dissolved substances in water(mainly due to iron, humic acids and tannins)
- TURBIDITY
– This has an effect on scattering of light, absorption and light penetration
- FOULING
– Due to chemical and biological deposits (mainly inorganic scale: iron, magnesium, calcium, aluminum, manganese, sodium, and anionic carbonate, phosphate, sulphate and organic biofilms) pretreatment required
- Iron < 0.3 ppm
- Manganese < 0.05 ppm
- Hydrogen Sulphide < 0.05 ppm
- Hardness < 7 gpg
- Suspended Solids < 10 ppm
- Excessive colour, turbidity, iron or organics, require additional treatment
NSF Standard 55
- CLASS A SYSTEMS
- systems capable of producing an ultraviolet dose at the alarm setpoint equivalent to a UV dose of 40 mJ/cm2 (40,000 microWsec/cm2 ) at 254 nm
- challenge organism is MS-2 Coliphage
- must have a 254nm UV sensor to monitor UV transmission (set at 70%)
- must have a flow control device
- must have either a visual alarm, audible alarm or shut-off device (solenoid)
- must have a NSF 53 turbidity filter for a general cyst claim (crypto & giardia are allowed)
- must pass applicable structural integrity tests (eliminates Teflon)
What is a UV (Ultraviolet) Sterilizer?
Ultraviolet or “UV” is a type of energy found in the electromagnetic spectrum, lying between x-rays and visible light. Although we cannot see UV light or rays, we are exposed to them every time we step out into the sun. In fact, UV light is responsible for causing sunburns.
UV Water Treatment systems use special lamps that emit UV light of a particular wavelength that have the ability, based on their length, to disrupt the DNA of micro-organisms. These UV light waves are also referred to as the Germicidal Spectrum or Frequency. The frequency used in killing micro-organisms is 254 nanometers (nm). As water flows through the UV system, living organisms in water are exposed to UV light which attacks the genetic code of the microorganism, eliminating the microorganism’s ability to function and reproduce. If a microorganism can no longer reproduce, it cannot multiply, therefore it cannot infect other organisms with which it has contact. This process of exposing water to the UV light is simple but effective, destroying 99.99% of harmful microorganisms without adding any chemicals to water.
Advantages Of Using A UV (Ultraviolet) Sterilizer For Water Treatment
Municipal water suppliers perform the necessary operations to meet water quality standards. But UV purification systems take water purification to a higher level—providing a safe solution against chlorine-resistant microorganisms such as Giardia and Cryptosporidium which cause thousands of documented health cases each year.
Effective – Destroys 99.99% of microorganisms
Environmentally Friendly – Go green! UV is an environmentally friendly alternative to chlorine disinfection and has no disinfection byproducts
Reliable – works night and day, 24/7, consistently keeping water safe
Cost-Effective – only lamp & sleeve replaced annually
Quick Process – water flows through the system without need for holding tank or reaction times
Low energy usage – low electrical needs
Conserves water – The UV purification process does not waste any water
Chemical free – no harmful chemicals need to be added
Essentially trouble-free – once installed, annual service is usually all that is required
Safe – no handling of chemicals
Clean – no dirty parts to dispose of
More effective than chlorine or chloramines – especially on some water borne cysts
FDA Approved – one of only 4 methods approved for disinfection by US Food & Drug Administration (FDA)
Taste and odor – Chemical disinfection methods (such as chlorine) change the taste & odor of water and produce byproducts. UV does not.
Most ultraviolet water treatment systems require only an annual change of lamp – as simple as changing a light bulb – and a periodic change of a filter cartridge that protects the lamp. Although the initial cost of some UV applications are a bit more than chlorination, the low operating costs make it pay for itself in no time.
Parts of the Ultraviolet System
Ultraviolet Power Supply Unit – This is the main controlof the Ultraviolet system. Some systems have a very simple controller, and others have a more complicated system that includes alarms, lamp change timers, trouble indicator lights, and more. Although Ultraviolet units vary in complexity and size, all controllers do basically the same thing of controlling the electrical output of the lamp and powers the UV-C light needed for water purification.
Inlet for untreated water.
Ultraviolet System Housing – This part of the system contains the Ultraviolet sleeve and lamp, and also controls the flow of water through the system.
Outlet for treated (clean) water.
UV Bulb – The lamp of an UV system produces UV-C, which is Ultraviolet light considered to be germicidal. However, different lamps perform different functions, so they type of lamp used will be contingent on the application and disinfection requirements.
UV Quartz Sleeve – The quartz sleeve is made of quartz glass and is there to protect the UV lamp which is powered by electricity from the flow of water. The UV lamp transmits light through the tube into the water. It is important to clean the sleeve (generally when the lamp is changed) as minerals and contaminants in the water can cloud the glass tube.
Contaminants that the UV (Ultraviolet) System Can Remove
Viruses, Bacteria, Cysts, Coliform, Salmonella, Giardia, E.coli, Cryptosporidium, Typhoid
Fever, Flu, Polio, Dysentery, Cholera, Meningitis, Infectious, Hepatitis
How does Ultraviolet Sterilization Work?
Many water purification systems take advantage of a UV water sterilizer even after processing their water. This is a well-known practice. Companies like Puritech highly recommend UV sterilizers as a post treatment when treating water. Throughout the years ultraviolet technology has become well established as a chosen method for effective and economical water disinfection. Ultraviolet water sterilization claims many advantages: All microorganisms are virtually susceptible to ultraviolet disinfection. For every penny of operating cost, hundreds of gallons of water are purified. NO additional chemicals are added and there’s no danger of overdosing. Once the water leaves the purifier, it is ready for use with no further contact time required. It has simple and easy to install and maintain. Compact units need a small space to operate and store. Ultraviolet water sterilizers deliver ongoing disinfection without special attention or measurement. There are no detections of chlorine taste or corrosion problems.
The Difference
Between Our UV syste
And The Competition
- The UV chamber quality is worse then us, as they use low quality stainless steel then our company which means they are more easily get rusted after using a few months
- The UV Ballast is not the same, they use less components then us
- The packing is not as good as us, we use strong carton box which insure safty transpoation
- Our welding technology is also better then your new UV supplier too, we can make sure that is no water leak from our UV chamber
- We have passed the CE, ROHS certifications and also the local certification for Italy market which you also know it.
If you check inside of the UV chamber you will notice the differences.
UV LAMP DIFFERENCE
Puritech
Casing: Fire proof PC material
Casing: Nice looking and good touch
Certificate: CE,ROHS from TUV and SGS
Principle: Stable and long working life
Working Temp.: -10˚C – 55˚C
Start: Soft start insure long lamp life
PCB Board: PCEM-1，PFR-4 board
Electromagnetism: EMC stardard
Overheat: Big size Inductor | Protection of Overheat
Protection: Cord with fault protection
Alarm for malfunction: Two working lights and alarm
Competition
Casing: No fire proof
Casing: Smaller case and bad finish
Certificate: No.
Principle: Easy get burned
Working Temp.: 0˚C – 55˚C
Start: No soft start, short lamp life
PCB Board: Very thin PFR-0 board
Electromagnetism: No Electromagnetism
Overheat: Smaller size, easy overheat
Protection: Cord without fault protection
Alarm for malfunction: No Beep and alarm
UV BALLAST DIFFERENCE
Puritech
Material: Natural Quartz
Penetration Rate: 80% For Ultraviolet Light.
Lamp Life: Minimum 8000Hrs
Inside Transplant, No Small Bubble
Competition
Material: Made by Borax Material
Penetration Rate: <50% For Ultraviolet Light.
Lamp Life: <8000Hrs Which will not be able to kill bacteria even the lamp is still
Inside with no small bubble