What is the pH requirement for lime stabilization to meet Class B stabilization standards within the first two hours?

To meet Class B stabilization standards during lime stabilization, the pH must reach a level that effectively reduces the concentration of pathogens while enhancing the treatment of wastewater solids. A pH of 12 is the minimum requirement within the first two hours of the stabilization process. At this level, the high alkalinity created by lime promotes the inactivation of harmful microorganisms, ensuring that the treated sludge meets the health standards necessary for land application.

Successful lime stabilization not only helps in pathogen control but also improves the overall quality of the sludge by enhancing its dewaterability and reducing odor. Other pH levels suggested, like 10, 11, or 11.5, do not achieve the same level of pathogen reduction and stabilization efficiency required to meet Class B standards within the specified timeframe. Therefore, a pH of 12 is critical for ensuring compliance and effective treatment during the lime stabilization process.