5. Sludge treatment, reuse and disposal. Sludge is produced from the treatment of wastewater in on-site (e.g. septic tank) and off-site (e.g. activated sludge) systems. This is inherently so because a primary aim of wastewater treatment is removing solids from the wastewater.
Definition of central. 1  1 : containing or constituting a center. 2  2 : of primary importance : essential, principal the central character of the novel. 3  3a : situated at, in, or near the center the central part of the stateb : easily accessible from outlying districts a central location for the new theater.
A character is a person or creature that interacts with others within a story. There are different kinds of characters in stories, and different ways to describe them. Character traits-elements of a character's personality that define who the character is.Shrek is grouchy and irritable, but kind-hearted; these are his character traits. In the Spider-Man movies, Peter Parker's character traits are his intelligence, his shyness, and his cautiousness.hese are usually minor, flat characters. Dynamic character a character whose personality changes during the course of the story; a character who grows, emotionally, due to or learns from the actions or events in the story.