UV sterilizer selection according to the nature of the water and the amount of water to determine

The principle of sterilization of ultraviolet sterilizer

Ultraviolet sterilizers are also called ultraviolet sterilizers, which are divided into air ultraviolet sterilizers and water sterilizers. Because ultraviolet sterilizers are mostly used in water treatment, ultraviolet sterilizers are commonly referred to as water sterilizers, and are used in water treatment. The UV sterilizer is a device that uses ultraviolet germicidal lamps to kill bacteria and viruses in the water. It is classified into closed pressure type and open gravity type. Due to the large flow of sewage and the use of ditches, most of the UV sterilizers used for sewerage are UV sterilizers. Device, and drinking water disinfection requirements are strict, equipment precision requirements are higher, so more use of closed pressure type, also known as pipeline UV sterilizer. The main components of the UV sterilizer include ultraviolet germicidal lamp, ultraviolet ballast, high purity quartz tube, reaction chamber (closed pressure type open, open gravity type not), sealing assembly, and distribution box. Among them, the irradiation intensity of the UV lamp and the effective use time of the lamp (not the same as the use time), the purity of the material of the quartz tube, and the stable and unstable output voltage of the ballast determine the sterilization effect of this ultraviolet sterilizer and the value of this product. High-quality ultraviolet germicidal lamps have an effective life of more than 13,000 hours. The useful life of poor-quality UV germicidal lamps is very short. UV sterilizer manufacturers Shijiazhuang Ling Zhuo environmental protection equipment Co., Ltd. selection of high-quality UV germicidal lamp and high-purity quartz tube made of stainless steel UV sterilizer by its high quality and low price favored by customers.
UV disinfection is performed by irradiating water with ultraviolet rays. Ultraviolet light is divided into three wavelength bands: A, B, and C, and vacuum ultraviolet light, A-band 320nm to 400nm, B-band 275nm to 320nm, C-band 200nm to 275nm, and vacuum ultraviolet rays 100nm to 200nm. Water disinfection uses C-band ultraviolet light. Light quantum theory holds that light is a special form of material operation. It is a stream of particles that are not connected. Ultraviolet photons with a wavelength of 253.7 nm each have an energy of 4.9 eV. When ultraviolet light is irradiated to microorganisms, energy transmission and accumulation occurs, and the accumulation results in the inactivation of microorganisms, thereby achieving the purpose of disinfection.
UV sterilizer selection according to the nature of the water and the amount of water to determine UV sterilizer selection depends on the nature of the water and the amount of water required to deal with the hour to determine. The general calculations are:
The disinfection capacity of the drinking water UV sterilizer refers to the function of killing microorganisms in water under the condition of rated water intake. Its physical expression indicates the irradiation dose in this state:
W=IXV/Q×3.6 (1)
Where W - radiation dose, μW / (cm2 · s);
I - radiation intensity, μW/cm2;
V - effective water volume of the sterilizer, L;
Q——The rated water intake of the sterilizer, m3/h.
The central issue in determining the disinfector's ability to disinfect is how to determine the dose of radiation. As can be seen from Table 1, different radiation doses are required to kill different microorganisms, and microorganisms present in water are various. If the selected irradiation dose is too high, unnecessary energy will be wasted, and if it is too low, it will not achieve the purpose of disinfection. Disinfection of water should focus on the killing of intestinal bacteria that pass water pollution diseases. It is generally believed that the minimum dose of radiation that a drinking water UV sterilizer can provide is not less than 9 000 μW/(cm2·s), and the product should be larger than 12 000 μW at the factory. / (cm2 · s).
In drinking water UV sterilizers, the intensity of UV radiation at different points is different. Ultraviolet rays emitted from the lamp tube pass through the quartz tube and cause a certain attenuation. The intensity of the water passing through the water layer decreases as the depth of the water layer increases. The following relationship exists:
I=I0e-kd (2)
In the formula I - radiation intensity of different water depths, μW/(cm2 · s);
I0 - supersonic radiation intensity, μW/(cm2 · s);
K——depth of water layer, cm;
D—water absorption coefficient, cm-1.
In the above formula, the water absorption coefficient is in turn related to turbidity, chroma, and iron content.
In the case of multiple lamps in an ultraviolet sterilizer for drinking water, the calculation of the distribution of the ultraviolet radiation intensity in the section of the tube is relatively complicated, and it is the primary problem in the design of the structure to ensure that the strength of each point is substantially uniform.
During the effective use of the sterilizer, the radiation dose decreases with time. This is mainly due to changes in the radiant intensity of the lamp, the scale of the surface of the sterilizer cylinder and the surface of the quartz sleeve, and the reflectance and transmittance of ultraviolet rays. Purple reduction is also an important reason.
According to different water quality, we are divided into pure water, residential secondary water supply (well water), recycled water, sewage. Different water quality required to achieve the effect of the lamp power is different, the bactericidal effect is determined by the radiation dose received by the microorganisms, but also by the UV output energy, and lamp type, light intensity and use time, with When the lamp ages, it will lose 30%-50% of its intensity. Ultraviolet radiation dose refers to the amount of ultraviolet light of a specific wavelength when a certain bacterial inactivation rate is reached: the irradiation dose (J/m2)=irradiation time (s)×UVC intensity (W/m2) The larger the irradiation dose, the more effective the disinfection is. High, due to equipment size requirements, the general exposure time is only a few seconds, therefore, the UVC output intensity of the lamp becomes a measure of ultraviolet light onclick="g ('disinfection equipment');> disinfection equipment performance is the most important parameter. In urban sewage disinfection, the average irradiation dose is generally more than 300 J/m2. Below this value, there may be a phenomenon of photoreactivation, in which pathogens cannot be completely killed. When they emerge from the channels and receive visible light, they are revived and the bactericidal effect is reduced. The higher the sterilization efficiency requirement, the greater the required irradiation dose. The main factor affecting the micro-organisms to receive sufficient dose of UV light is the light transmittance (at 254 nm). When the UVC output intensity and irradiation time are fixed, the change of light transmittance will cause the actual dose of micro-organisms to be changed.

Mini Co2 Laser Engraving Cutting Machine

This machine is equipped with DSP Control System for RDdraw directly,also supports CoreDraw and Auto CAD and other advance software. It must connect with computer with USB cable when you change the settings of machine for the design files,you can transfer the file with USB memory stick to the machine, or can download it to the machine directly with USB cable from computer. Even on the same Job, you can do setting with different colour in the software and also can making holes.And it can the legs separate from the main body of the machine. The machine has doors which can be opened to accommodate larger materials.

Mini Co2 Laser Engraving Cutting Machine,Co2 Laser Engraving Machine For Metal,Fiber Laser Metal Engraving Marking Machine,Desktop Laser Engraving Machine For Metal

Zhongcan Technology Co.,Ltd , https://www.zhongcantechcn.com