What happens to the pH of wastewater if alkalinity is insufficient during nitrification?

During the nitrification process, ammonia is converted into nitrate by nitrifying bacteria, which generates hydrogen ions (H+). If the wastewater does not have sufficient alkalinity, it lacks the buffering capacity needed to neutralize these hydrogen ions. This leads to a decrease in pH, making the wastewater more acidic.

Sufficient alkalinity acts as a buffer, helping to stabilize the pH during biological processes. When alkalinity is low, the hydrogen ions produced can overwhelm the buffering capacity, causing the pH to drop significantly as more hydrogen ions are released than can be neutralized. This is crucial in wastewater treatment because an optimal pH range is necessary for the health of the nitrifying bacteria and overall efficiency of the treatment process.