Ultraviolet lamp basic common sense
-- Lamp is actually belongs to a low-pressure mercury lamp. Is the use of low-pressure mercury lamp mercury lower vapor pressure (<10-2 Pa) issued by the intensification of UV, its luminescence spectra mainly two things: One is the 253.7 nm wavelength; Another is a 185 nm wavelength, the two are UV invisible to the naked eye.
-- Used to use fluorescent lighting, energy-saving lamps are also low pressure mercury lamp, rely on the low-pressure mercury vapour was launched after UV excitation, 254 nm wavelength ultraviolet radiation is given to the visible light phosphors, if changes in the composition and phosphor ratio, it can issue we usually see the different colors of light.
-- Lamp need not translate into visible light, the wavelength of 253.7 nm can play good bactericidal effect, it is because of the light absorption spectrum there is a law, 250 to 270 nm in the UV absorption maximum was UV absorption in the role of genetic material - DNA, which play a role in Gwanghwamun, the UV energy was the son of the base pairs in DNA absorption, caused genetic material mutates so that the bacteria can not be immediately killed or breeding future generations achieve the purpose of sterilization.
-- The use of fluorescent lamps and energy-saving lamps made of glass, 253.7 nm ultraviolet not come out thoroughly, and we can not do sterilization used lights, quartz glass on the UV transmittance high of 90%, are doing the best lamp materials, but the performance of quartz glass and glass performance in the great difference (mainly different coefficient of thermal expansion), the seal can not be used ordinary high degree of automation closure round approach, which makes the manufacture of lamp technology content is higher than that of ordinary energy-saving lamps.
-- There is a thoroughly UV glass, known as the high boron glass, its UV transmittance of quartz glass is about 60 per cent of its production technology and energy-saving lamps, in which its costs and prices Quartz glass production than the lamp a far cry from several watts lamp only a few million, but it is far smaller than in the performance of quartz lamp. Seen in the following several aspects:
---- 1 transmittance different in the same specifications as the same ballast test, quartz glass lamp is a high-intensity UV lamp boron glass more than 1.5 times;
---- 2, boron glass high intensity UV light attenuation very easily, it lights after hundreds of hours on the UV intensity dropped significantly to the initial 50% to 70%. In the hands of users, although that lamp is bright, but it may have been a non-functional. The quartz glass optical attenuation level is far less than high boron lights, if production process clearance, quartz lamps in the lighting Optical Attenuator 2000-3000 hours, optical attenuation to the initial 80 percent to 70 percent, and later as long as the lights do not eliminate, the extent of bad light will become increasingly smaller.
-- Domestic lamp customers may be able to understand the lamp Phillips, Phillips is a lamp with a glass close to the manufacture of glass, quartz glass rather than create, and its transmission rate of nearly quartz Glass transmittance than China's high boron glass lamps would be much higher, use a higher degree of automation of the production of energy-saving lamps production, which relied mainly on their lights refining this glass technology. The disadvantage is that it can not produce ozone.
-- Quartz lamp is another characteristic of ozone can be issued. The quartz glass on the short-wave 185 nm UV transmittance are also high, 185 nm UV ionizing air to produce ozone, high concentrations of ozone on human disadvantage, but in no occasion to use, ozone can sterilization, disinfection, can just cover the UV only spread along a straight line, there are dead ends disinfection shortcomings.
-- Some occasions not have ozone, can also use the quartz lamp, which in refining quartz glass when it added an element - titanium (Ti), through its 200 nm in the UV deadline for the following occurred, and by the 254 nm UV basically no impact, that is not what is commonly known as ozone lamp.
-- From the above analysis, done using quartz glass lamp is the best option. At the domestic level, the health sector, already do not recommend the use of high boron lamp, in the United States, Canada, Japan UV lamp production are generally quartz glass.
-- However, with the production of quartz glass lamp can do is not necessarily good, because they need to resolve two major issues.
---- 1, higher costs
Have already referred to the special nature of quartz glass, quartz lamp makes the production can not scale, mechanized production, but only to hand in the production, making the cost of quartz lamp higher. Domestic manufacturers UV lamp a few dozen dollars, the foreign imports to China on 100 or even several hundred yuan. High price hindered its further application.
---- 2, the larger-bad
-- Quartz lamp may also be a problem there - life is not long. Life is not long there are two concepts: one is not long life lighting is not at the length of time, lights out, and this is mainly electrode is not properly handled. Quartz processing required for the heat, if not handled properly, will lead to damage to the cathode, for a period of time at the lights eliminate the second refers to the concept of useful life, even if the lights do not put out, but the intensity of UV attenuation fast, reached 30 percent, Clearly shows that China UV lamp level of quality than abroad will be much lower.
-- Shangyu xin xin ultraviolet lamp factory Under this situation, in early 1999 started to organize forces on high-intensity, long-life low-pressure mercury lamp UV (commonly known as sterilization method called HEC) After more than a year of efforts, we have tackled this subject , and in the following two areas we identified the advantages.
-- First, the current cost of production of quartz lamp domestic manufacturers are to the mainly manual, especially the major processes - Seal manually, allowing for the generally high costs, poor product consistency, it is difficult to guarantee reliability. Prone to leakage problem is chronic, chronic leakage is a major reason why the quartz electrode and seal well. Star-automatic sealing method, productivity and yield greater leakage of <0.5%, greatly enhanced reliability, and the unit cost significantly lower than peers, the price is very competitive.
-- Second, the active life of the general manufacturers quartz lamp lighting points its hours without problems, but did not put out the lamp often can not be used, for example, hospitals use 30 watts quartz disinfection lights, the initial generally 100
W/cm2 (1.0 metres) used after a period of time (about 1500 hours), and then measuring probe ultraviolet (1.0 meters) less than 70
W/cm2, this lamp will have new ones, so as to avoid disinfection effectiveness good.
-- Create a UV light intensity from the reasons for the decay of the very complicated mechanism for fluorescent lamps (such as energy-saving lamps)-bad, in theory, have a more mature understanding, such as University in 1999 and shangyu Research on the "compact energy-saving lighting failure mechanism analysis" of the Ministry of Education presented the first prize. However, quartz UV light and fluorescent light bad light on the mechanism of failure from not identical, quartz glass and fluorescent lamps because the process different, to use high-temperature quartz glass Sealing; second, quartz glass and the glass itself, in its raw materials , the production process is different, the nature of still greater, and it has a certain impact UV bad.
-- The "Quartz UV light failure mechanism" study, the Star Limited, technology development center further, but how to reduce the UV decline has been very effective and reliable solution.
-- This approach is through special handling, making lower attenuation in the UV intensity during the entire life of only about 20 percent. For example, 30 watt lights, UV-light for the initial 100
W/cm2 (1.0 metres), even though more than 6,000 hours to the point, there are strong UV 80-90
W/cm2, 7,000 hours also 254 nm UV intensity than 70
W/cm2, in this technology, Philips has a similar application. Make long-life ultraviolet lamp possible.
-- UV lamp is used generically to the air, surface, water for disinfection and sterilization. 254nm wavelength can be bacteria and viruses can effectively kill, our predecessors have long been a substantial amount of research, is not suspected of fact. UV disinfection is characterized by broad-spectrum, high-temperature have some difficulty in eradicating the virus, with the elimination of ultraviolet quickly, as the mechanism of UV disinfection and other methods different.
-- UV to kill bacteria and viruses and ultraviolet radiation dose, dose = exposure time (S)
irradiation intensity (
W/cm2), the radiation dose theoretically general design requirements if more than 30000 UV intensity
W/cm2 low, as a long time, and when slightly higher intensity to achieve the same effect, if not in the long-time circumstances, to choose the high-power high-intensity ultraviolet light. Normally various bacteria and viruses irradiation dose required to kill the different points in the killing irradiation intensity can be measured calculated exposure time, the object of the disinfection was not aware of the circumstances, the extended exposure time normally required to ensure that sterilization efficiency. Since UV will kill cells, ultraviolet disinfection, attention should be paid to direct exposure to the skin, particularly the eyes, ultraviolet lamp lit lamp, not open, not because of short-wave ultraviolet light through the glass, wearing glasses eye injury can be avoided. If we injured, in most cases, are not OK, as the sunlight burns, can be a serious drop in human milk or eye drops to help recovery. In some occasions, do not use ozone lamp, when high concentrations of ozone on unfavorable.
-- Sterilization uses ultraviolet very broad, hospitals, schools, nurseries, cinemas, buses, offices, families, it can purify the air, eliminate Meimei, the outside can have a certain amount of negative oxygen ions, the UV disinfection of rooms, especially fresh air. In a public place, the ultraviolet disinfection, can avoid some germs spread through the air or transmitted by the object's surface. Long-life ultraviolet lamp in the water disinfection, and environmental protection projects of great significance in the use of water disinfection equipment, such as water systems, generally within 24 hours operation, ultraviolet lamp life and reliability requirements are high, if short lamp life , the high cost of lamp replacement, but is also very convenient.
-- UV lamp in the water disinfection of the application of the 1980s popular in Western countries, China in the 1990s, it than the traditional chlorine disinfection is incomparable superiority. Chlorine disinfection: in the water will form a chlorine compound, which is a carcinogen, and the high concentration of chlorine will also have a taste, if they drink raw water will be clearly heard to this Guaimei. Now there is a water disinfection methods: ozone, ozone can sterilization, but its high concentrations, ozone decomposition to extend the time, it is likely to close the room piped to the residents. Ozone water said to beauty , but not to drink, and its bad taste. If the concentration of lower disinfection also weakened. In addition to ozone disinfection to prevent leakage.
-- And so, UV disinfection in the water disinfection have an unparalleled advantage: UV intensity can be measured, can be monitored on-line control can be achieved, understand the sanitizing effect, but not with any side effects, in the field of water disinfection prospects are incalculable