The resistance characteristic of the HEPA filter is one of the important characteristics of the high-efficiency filter. Under the premise of meeting the efficiency of people's needs, the resistance characteristic is related to the cost of use. The resistance is small, the energy consumption is low, and the cost is saved. Therefore, the resistance performance of the filter Becomes one of the important indicators that people pay attention to.
According to our experimental measurement data on the HEPA filter, the relationship between the average wind speed of the two different structure filters of glass fiber and the PTFE filter and the filter pressure difference is obtained. As the wind speed increases, the resistance of the HEPA filter is equal The linear increase from low to high, and the two straight lines derived from the two glass fiber filters basically coincide.
It is easy to see that when the filtering wind speed is 1m/s, the resistance of the glass fiber filter is about four times that of the PTFE filter. Knowing the area of the filter, the relationship between the surface speed and the pressure difference of the filter can be obtained: from the experimental data, it can be seen that as the wind speed increases, the resistance of the high-efficiency filter increases linearly from low to high, and the two glass fibers The two straight lines obtained by the two filters basically coincide. It is easy to see that when the filtering wind speed is 1m/s, the resistance of the glass fiber filter is about four times that of the PTFE filter.
Knowing the area of the filter, the relationship between the surface velocity and the filter pressure difference can be obtained: because the two filter papers are different, the relationship between the surface velocity of the two glass fiber filters and the filter pressure difference is not completely consistent, and the same The resistance of the 610×610×90mm filter at surface speed is higher than that of the 610×610×150mm filter.
But obviously, at the same surface speed, the resistance of the glass fiber filter is higher than that of PTFE. It shows that PTFE is superior to glass fiber filter material in terms of resistance performance. In order to further understand the resistance characteristics of glass fiber filter material and PTFE, further experiments were done.
This further verifies the previous conclusion that under the same wind speed, the resistance of the glass fiber filter paper HEPA filter is higher than that of the PTFE HEPA filter. By comparing the resistance performance and filtration performance of PTFE HEPA filters and glass fiber HEPA filters, the application prospects of different HEPA filters are discussed.
From the experiment, we can draw the conclusion that wind speed is a very important factor affecting the filtration effect of the HEPA air filter. The higher the wind speed, the lower the filtration efficiency. This effect is more obvious for the PTFE HEPA filter, and the overall In terms of the filtering effect of PTFE high-efficiency filters, the filtering effect is worse than that of glass fiber high-efficiency filters, but its resistance is lower than that of glass fiber high-efficiency filters, so PTFE filter media is more suitable for making coarse-efficiency or sub-high-efficiency filters. Fiber filter material is more suitable for making high-efficiency or ultra-efficient high-efficiency filters.
In the experiment, the resistance of the glass fiber HEPA filter of 610×610×150mm is lower than that of the glass fiber HEPA filter of 610×610×90mm, and the filtration performance is higher than that of the glass fiber HEPA filter of 610×610×90mm. it is good.
At present, the price of pure PTFE filter material is higher than that of glass fiber, but compared with glass fiber, PTFE has better corrosion resistance and hydrolysis than glass fiber. At the same time, it has good temperature resistance, the continuous operating temperature is 260 degrees Celsius, and the instantaneous operating temperature is 2.5 times that of Flame retardant filter media, which can reach 300 degrees Celsius.
Therefore, when producing high-efficiency filters, comprehensive consideration should be given to various factors that give consideration to both technical performance and economic performance.