Denitrification Deep Bed Filter (DDBF)
The denitrification deep bed filter (DDBF) is an advanced wastewater treatment process that combines biological denitrification, suspended solids (SS) retention, and phosphorus removal. Biological denitrification under anoxic conditions functions together with the physical retention of the deep filter media to remove nitrogen, phosphorus, and SS, providing advanced treatment for total nitrogen (TN), total phosphorus (TP), and SS control.
The denitrification deep bed filter is used for municipal WWTP upgrading and retrofitting, industrial effluent advanced nitrogen removal, surface-water treatment, and reclaimed water reuse and recycling projects. Additionally, it can also serve as a biological denitrification filter in wastewater treatment systems that require stringent effluent limits.
- Treatment Capacity per Unit (m³/h): 100–10,000
- Design Filtration Rate (m/h): 5–10
- Media Bed Depth (m): 1.8–3.0
- Air Backwash Rate (L/(m²·s)): 15–20
- Water Backwash Rate (L/(m²·s)): 6–8
- Effluent SS (mg/L): ≤5
- Effluent Total Nitrogen (mg/L): ≤3–10 (as required)
- Construction Material: Coated Carbon Steel / Stainless Steel / Reinforced Concrete
Note:
- The above parameters are design values based on standard operating conditions which can be customized and adjusted according to the quality of the influent water and the effluent discharge standards;
- The filter structure can be customized using materials such as corrosion-resistant carbon steel or 304/316L stainless steel; the civil engineering tank structure can be specially designed based on on-site project conditions, wherein construction drawings will be provided;
- The denitrification filtration system can be equipped with precise carbon source dosing and online water quality monitoring systems to achieve intelligent control and management throughout the entire process.
- Influent distribution zone: Distributes water uniformly and ensures stable flow across the full filter area.
- Filter media layer: Homogeneous quartz sand filter that carries the denitrifying biofilm and achieves denitrification as well as SS retention.
- Support layer: Graded gravel laid in layers to keep the filter media stable and the air-water distribution uniform.
- Air-water distribution system: Long-stem filter nozzles for combined air-water backwashing.
- Backwash system: Pumps and blowers for efficient regeneration of the filter bed.
- Carbon source dosing system: Meters carbon source to support denitrifying bacteria.