Which method is specifically a solids treatment dewatering process?

Incineration is not a solids treatment dewatering process; instead, it is a method of waste treatment that involves burning solid waste at high temperatures to reduce it to ash, gases, and heat. The process is designed to dispose of waste rather than to remove moisture from solids.

The correct answer would involve a method that reduces the moisture content of solids, allowing for easier handling and disposal. Dewatering processes are critical in wastewater treatment because they concentrate the solids, making subsequent treatment or disposal more efficient.

Among the options provided, gravity is a dewatering method. It uses gravity to separate water from solids in a sedimentation process or by allowing liquids to drain away from the solids. This method can effectively concentrate solids by allowing the water to flow away, which is a key aspect of dewatering.

Flotation can also be a technique for separating solids from liquids, but it typically involves introducing air bubbles to lift solids to the surface where they can be skimmed off, rather than simply draining moisture as in gravity-based processes.

Composting is a biological process involving the breakdown of organic matter, which may indeed include some water removal but is primarily aimed at transforming organic materials into soil amendment rather than strictly dewatering.

Thus, recognizing that gravity is the method specifically