Turning Food Waste into Clean Water: The Science Behind It

Turning food waste into clean water. This is not just a dream but a reality. Food waste is a big problem, but methane fermentation can help. This process creates a liquid that has lots of ammonium, which is hard to deal with. That's where partial nitrification (PN) comes in. It's a crucial step in treating this liquid. PN helps reduce ammonium and produces nitrite, which is needed for the next step, called Anammox. The key to making PN work well is controlling the air flow. A special reactor, called an airlift reactor, was used for over a year. It showed that PN can handle high loads. The reactor kept the ammonium removal efficiency between 50. 2% and 57. 1%. This was done by carefully controlling the air flow. The best conditions for PN were found to be a temperature range of 20-40°C and a pH range of 7. 5-8. 5. The reactor also produced a lot of Nitrosomonas, a type of bacteria that helps with PN. Other bacteria that could mess things up were barely found. This shows that the process was stable and effective. The study also looked at how temperature and pH affect the bacteria's activity. They used different models to figure this out. The results were very accurate, with R² values close to 1. This means the models were a good fit for the data. The study also proposed a new way to control the air flow. This method uses a positive feedback loop, which means the system can adjust itself based on what's happening. This makes the reactor even more effective at treating high-ammonia liquid. The findings of this study are important. They show that PN can be a reliable way to treat dewatering liquid from food-waste methane fermentation. This could lead to better waste management and cleaner water.