Application of LEVAPOR biofilm technology in biological filter阅读：23083 更新时间：2011-05-26 17:11 Source: State Environmental Protection Technology Co., Ltd. Guilin De Read: 23083 Updated: 2011-05-26 17:11
Biological filter reactor
The biological filter is generally used as a post-treatment reaction tank. The process is particularly suitable for the advanced treatment of sewage that has been subjected to biochemical pretreatment, and the concentration of pollutants and suspended particles in the wastewater is relatively low. Because of its low concentration, the hydraulic retention time is short, which means that the volume of the reaction cell is small. This process is particularly suitable for removing trace amounts of pollutants if the appropriate biological species are injected.
How the biological filter using the LEVAPOR process works
In the biological filter, there are still some flocs without precipitation and microbial cells that still have high activity. These materials can be attached to the aerated LEVAPOR suspension filler with a large specific surface area and adsorption capacity. The remaining pollutants (COD) in sewage are nutrients. The LEVAPOR biofilter contains 60% -70% LEVAPOR suspension filler in volume ratio. Depending on the hydraulic retention time, COD in the sewage can be reduced by 40%, and the remaining ammonia nitrogen and toxic substances can be further removed.
The following is a process flow diagram and a top view of a biological filter bed reactor using LEVAPOR biofilm.
Biological filter process flow chart
Top view of biological filter
Operation mode of biological filter using LEVAPOR process
The sewage from the front of the treatment system enters the biological filter in a countercurrent direction from above and uniformly distributes the water. After passing through the aerated filter bed and sieve plate (at the bottom of the reaction tank), it is introduced from the filter wall to the upper part of the reaction tank Then leave the filter.
In this process, the hydraulic retention time can be adjusted according to the water quantity and water quality. In general, the hydraulic retention time is about 30 minutes to 60 minutes. If the remaining load is still large (such as complex industrial sewage), the hydraulic retention time can also be extended to 4-5 hours.
The sludge in the filter settles well and can be pumped away at the bottom of the tank.
The following two graphs show the additional COD removal rate of a chemical plant's wastewater after passing through a biological filter, and the comparison between LEVAPOR-free and LEVAPOR biofilm technology. It can be clearly observed that the COD removal rate is higher after using the LEVAPOR biofilm technology, and the effect is better from the probability distribution of the removal rate.
The following table shows the analysis of the treatment effect of different types of sewage in the biological filter using LEVAPOR biofilm technology. It can be seen from the chart that the removal rate of various types of pollutants is very high after using LEVAPOR biofilters in both municipal and industrial projects.
The following figure shows the analysis of the effect of degrading bisphenol-A (BPA) in the LEVAPOR biofilter. Blue indicates water inflow and red indicates water.