Which method is used for the reduction process in sludge treatment?

The reduction process in sludge treatment primarily involves the transformation and stabilization of organic materials in the sludge to reduce its volume and enhance its safeness for disposal or further processing. Biological digestion is a key method in this context.

Biological digestion utilizes microorganisms to break down organic matter under controlled conditions, leading to the stabilization of the sludge. Through this process, organic compounds are converted into simpler substances, thereby significantly reducing the mass and volume of the sludge. This method not only reduces the amount of sludge that needs to be processed or disposed of but also produces biogas, which can be utilized as a renewable energy source.

While incineration can also reduce sludge volume by converting it to ash and gases, it does not stabilize the organic content and may not be considered a biological reduction method. Other methods, like chemical treatments and pressurized drying, serve different purposes, such as disinfection or dewatering, rather than biological reduction. Hence, biological digestion is the appropriate technique for the reduction process in sludge treatment.