Which of the following processes involves mechanically removing grit from wastewater?

The process that specifically focuses on the mechanical removal of grit from wastewater is known as grit removal. This process is essential in wastewater treatment as it helps to separate heavier particles, such as sand, gravel, and other abrasive materials, from the liquid. By removing grit at this stage, subsequent treatment processes can operate more effectively and with reduced risk of damage due to wear from these particles.

Grit removal typically involves using apparatuses like grit chambers, where the flow velocity is reduced, allowing the heavier grit particles to settle to the bottom while the lighter organic matter remains suspended in the water. This separation is crucial in preventing damage to pumps and other equipment in the treatment facility, ensuring the overall efficiency and longevity of the treatment system.

While sedimentation also deals with the separation of particles, its primary focus is on solids settling from liquids based on their density rather than specifically targeting grit. Filtration involves passing water through a medium to remove particles, but does not specifically address the focused removal of grit. Comminution refers to the process of breaking down solids into smaller pieces, often related to organic material rather than the mechanical removal of grit.