Which method involves mixing solids with a bulking agent and waiting for biological stabilization?

The method that involves mixing solids with a bulking agent and waiting for biological stabilization is composting. This process is designed to enhance the decomposition of organic materials through the addition of bulking agents like wood chips or straw. These agents provide necessary air spaces for adequate aeration, which is crucial for the aerobic microorganisms that break down the organic matter.

During composting, microorganisms metabolize the organic solids, producing heat which further accelerates decomposition and assists in the stabilization of the material. As the process continues, the material transforms into a stable end product that can be used as a soil amendment. This biological stabilization is an essential aspect of composting as it helps in reducing the pathogens and odors associated with raw waste.

While the other methods listed have their purposes in wastewater treatment or solid waste management, they do not specifically focus on the biological stabilization of solids mixed with bulking agents. Lime stabilization, for example, involves adding lime to waste solids to enhance pathogen reduction and stabilize the material but does not rely on the biological processes of decay. Gravity thickening is used primarily to increase the solids concentration by using gravitational forces but does not involve biological activity. Chlorine oxidation refers to a disinfection process that targets pathogens and organic matter using chlorine, rather than