Air filters are gases that pose a significant threat to human health when dealing with radioactive waste gas,

The method of air filter treatment is quite important, so currently air filters are generally used in the industry for treatment. The following will focus on the main functions of various air filters.

Air filter radioactive waste gas purification technology: There are many methods for waste gas purification, commonly used include filtration, adsorption, washing, retention decay, etc. The commonly used exhaust gas purification equipment includes: filtration: inlet pre filter (for dust removal in the inlet airflow, with a filtration efficiency of at least 85%) exhaust pre filter (installed before the high-efficiency air particle filter, to remove coarse dust in the airflow and improve the service life of the high-efficiency particulate air filter, with a filtration efficiency of at least 85%) high-efficiency filter (used to capture small particle dust in the airflow, with a filtration efficiency of at least 95%) High efficiency particulate air filter (absolute filter HEPA) is used to capture ultrafine particulate dust in exhaust gas, with a particle size of less than 0.3 μ Iodine filters (iodine adsorbers usually use 1% KI impregnated activated carbon as the medium, with an iodine removal rate of 99.9% for elemental iodine and 99% for organic iodine) and other types of filters (bag filters, metal sintered filters, ceramic candle filters, ruthenium filters).

According to the characteristics of the exhaust gas, appropriate process technology should be selected for purification treatment, and only after meeting the standards can emissions into the atmosphere be allowed. The secondary waste generated during the exhaust gas purification process (such as waste filter cores, waste activated carbon, waste filter bags, etc.) should be reasonably minimized.

The exhaust gas purification system should prevent leakage. The exhaust gas purification system may accumulate smoke and oil, and should prevent the occurrence of combustion accidents. For the retention decay storage system, there should be sufficient retention decay time and sufficient storage capacity (decay storage tanks are backup to each other). Regular testing and timely replacement of air filters are necessary to ensure filtration efficiency is met. When the radiation field intensity is high, replacing the filter should be done remotely.

Low wind speed improves the filtering effect of air filters:

Everyone knows that there is a certain relationship between the filtering effect of air filters and wind speed. Most people may think that the higher the wind speed, the better the filtering effect of air filters. However, in reality, the opposite is true. The lower the wind speed, the better the efficiency of "Zijing" brand air filters. For details, please refer to the detailed analysis below

The diffusion effect of small particle dust (Brownian motion) is obvious. When the wind speed is low, the airflow stays in the filtered data for a longer time, and the dust has more opportunities to collide with obstacles, resulting in higher filtration efficiency. Experience has shown that for high-efficiency filters, reducing wind speed by half will result in a decrease of nearly an order of magnitude in dust transmittance (increasing efficiency by 9), doubling wind speed will result in an increase of an order of magnitude in transmittance (decreasing efficiency by 9).

Similar to the effect of diffusion, when filtering data with static electricity (electret data), the longer the dust stays in the filter material, the greater the possibility of being adsorbed by the data. Changing the wind speed will significantly alter the filtering efficiency of static data. If you know there is static electricity on the data, when designing the air conditioning system, you should try to reduce the airflow through each filter as much as possible.

According to traditional theory, for large particle dust mainly based on inertia mechanism, the probability of dust colliding with fibers decreases and the filtration efficiency decreases as the wind speed decreases. However, in theory, this effect is not significant. As the wind speed decreases, the fiber's rebound force against dust also decreases, making it easier for dust to stick.

When the wind speed is high, the resistance is greater. If the service life of the filter is based on the final resistance, and the wind speed is high, the service life of the filter will be short. It is difficult for ordinary users to observe the effect of wind speed on filtration efficiency in practice, but it is much easier to observe the effect of wind speed on resistance.

Regarding high-efficiency filters, the speed of airflow passing through the filter material is generally between 0.01 and 0.04m/s. Within this range, the resistance of the air filter is directly proportional to the filtered air volume. For example, a 484 × four hundred and eighty-four × The 220mm "Zijing" brand high-efficiency filter has an initial resistance of 250Pa at a rated air volume of 1000m3/h. If the actual air volume in use is 500m3/h, its initial resistance can be reduced to 125Pa. Regarding the ordinary ventilation filter in the air conditioning box, the speed of airflow passing through the filter material is within the range of 0.13-1.0m/s. The resistance is no longer linearly related to the air volume, but an upward curve. If the air volume increases by 30%, the resistance may increase by 50%. If the filter resistance is a very important parameter for you, you need to ask the filter supplier for the resistance curve.