Views: 0 Author: Site Editor Publish Time: 2025-06-16 Origin: Site
The Advantages of Biological Fillers in Wastewater Treatment Engineering
Biological fillers provide a large attachment surface for microorganisms (specific surface area typically reaching 500-800 m²/m³), increasing the biological concentration in the reactor to 10-20 g/L (only 2-4 g/L in traditional activated sludge processes), thus improving the treatment efficiency per unit volume by 3-5 times.
Case Study: After adopting MBBR fillers in a chemical wastewater treatment project, the COD removal rate increased from 60% (traditional process) to over 85%, and the ammonia nitrogen removal rate increased from 50% to 95%.
The biofilm on the filler surface forms gradient environments of aerobic, anoxic, and anaerobic zones from outside to inside, enabling simultaneous functions such as organic matter degradation (COD), nitrification (ammonia nitrogen → nitrate), denitrification (nitrate → nitrogen), and phosphorus removal.
For example: In nitrogen-containing wastewater treatment, the synergistic effect of nitrifying bacteria in the aerobic zone of the filler surface and denitrifying bacteria in the inner anoxic zone can achieve a total nitrogen removal rate of over 80%.
The biofilm adheres to the fillers and is not easily lost with the water flow. When indicators such as influent COD and ammonia nitrogen suddenly increase, the high biomass can rapidly respond to maintain stable treatment effects.
Data Support: In a food wastewater treatment system, when the influent COD surged from 500 mg/L to 1,500 mg/L, the effluent COD remained stable below 100 mg/L due to the biofilm on the fillers.
By adjusting the filler filling rate (typically 30%-50%), it can flexibly cope with fluctuations in water volume or quality. For instance, every 10% increase in the filling rate can raise the treatment load by 15%, preventing system collapse due to sudden load changes.
Fillers continuously suspend and move under water flow or aeration, fully mixing with the wastewater, reducing the liquid film resistance on the biofilm surface. The oxygen utilization rate is 10%-20% higher than that of traditional processes, and aeration energy consumption is reduced by 20%-30%.
Collision and friction between fillers promote the shedding of aged biofilm, maintaining microbial activity and avoiding internal anaerobic corruption caused by excessive biofilm thickness.
No frequent backwashing (like traditional biological filters) or massive sludge discharge is required. Sludge production is 40%-50% less than that of the activated sludge method, reducing sludge treatment costs.
Engineering Example: After a municipal wastewater treatment plant was transformed into an MBBR process, annual electricity costs were saved by approximately 150,000 RMB, and sludge disposal costs were reduced by 30%.
High-concentration organic wastewater: For pharmaceutical and chemical wastewater, fillers can carry toxic-resistant flora to degrade refractory organics such as benzene series and phenols;
High-ammonia nitrogen wastewater: By domesticating nitrifying bacteria (e.g., nitrosomonas, nitrobacter) on the filler surface, the ammonia nitrogen removal rate can reach over 95% (effluent ≤5 mg/L);
Special pollutants: Modified fillers (e.g., loaded with iron oxides) can enhance heavy metal adsorption, or anaerobic ammonium oxidation (Anammox) fillers can treat high-ammonia nitrogen wastewater such as landfill leachate.
In the upgrading and reconstruction of municipal wastewater, it can serve as a tertiary treatment unit to strengthen nitrogen and phosphorus removal (e.g., effluent meeting Grade A standard);
Modular design is suitable for scenarios with tight land use (e.g., community and scenic area wastewater treatment stations), occupying 30% less land than traditional processes.
Made of polymer materials such as polyethylene (PE) and polypropylene (PP), which are anti-aging, acid-base resistant, and have a service life of ≥5 years, reducing replacement costs.
Inert materials have no toxic dissolution. Some fillers can be added with hydrophilic agents or modified fibers to accelerate biofilm formation (shortening the biofilm formation time of hydrophobic fillers by 1-2 weeks) and improve start-up efficiency.
| Application Scenario | Advantage Embodiment | Case Effect |
|---|---|---|
| Industrial wastewater (high-concentration/refractory) | Carry specific flora, resist toxic shocks, and increase COD removal rate to 85%-95% | Papermaking wastewater COD reduced from 1,200 mg/L to 80 mg/L, meeting reuse standards |
| Municipal wastewater upgrading and reconstruction | Strengthen nitrogen removal (ammonia nitrogen removal rate from 60% to 98%), meeting Grade A standard (ammonia nitrogen ≤5 mg/L) | After transformation, a wastewater plant's effluent ammonia nitrogen ≤1 mg/L |
| Decentralized wastewater treatment (communities/rural areas) | Small footprint, easy maintenance, modular expandability, and flexible treatment scale (50-5,000 m³/d) | Rural wastewater stations achieve ≥80% COD removal rate with an operation cost <0.5 RMB/ton |
| High-ammonia nitrogen wastewater (landfill leachate) | Rely on Anammox fillers to achieve a nitrogen removal load of 1.5 kgN/(m³·d), with energy consumption 40% lower than traditional processes | Leachate ammonia nitrogen reduced from 1,500 mg/L to 50 mg/L |
