Carbon-neutral wastewater treatment (2)
- Future energy-positive wastewater treatment process would consist of A and B stages: The A stage is for organic recovery and energy produce, while B stage is for nitrogen removal under low COD/N conditions. The low-energy N removal technology to be applied in step B will be an anaerobic ammonia oxidation (anammox)-based process.
- Anammox based nitrogen removal
- ① Single-stage PN/A process for sidestream N removal
The sidestream wastewater generated after the anaerobic digestion contains high concentration nitrogen, which increases the demand of nitrogen treatment load of the sewage treatment plant.
The PN/A process which combined partial nitritation (PN) and anaerobic ammonium oxidation (ANAMMOX) could reduce the aeration cost by 60% and save 100% external carbon source addition.
In our lab, we investigated the key operating parameters that affect fast-start up single stage PN/A process with different feeding strategies. We have operated a pilot scale single-stage anammox process in Suyoung WWTP in Busan, Korea. Based on the pilot plant experience, we are developing a field application project to treat sludge-dewatering wastewater.
- ① Single-stage PN/A process for sidestream N removal