BS 375 Lecture Notes - Lecture 11: Chemical Oxygen Demand, Biochemical Oxygen Demand, Total Organic Carbon

• School: University of the Sciences
• Department: Biological Sciences
• Course: BS 375

Document Summary

Domestic wastewater or sewage is a combination of human fecal matter, urine, and gray water. Gray water results from washing, bathing and meal preparation (kitchen sink) Water from industries and business establishments may also enter the system. The amount of organic matter in domestic wastes determines the degree of biological treatments required. Three tests are used to assess to the amount of organic matter: toc: total organic carbon, bod: biochemical oxygen demand, cod: chemical oxygen demand. The chief source of pathogenic microbes is from infected persons. Sewage: the used water supply containing domestic waste together with human excrement, wash water and industrial waste including acids, animal matter, greases, vegetable matter and stormwater. Treatment principle: the basic principle in sewage treatment is that water is separated from waste while solid organic matter is biodegraded by microorganisms to simple compounds like nitrates, sulfates, carbonates, co2 and methane. It has cylindrical rings with pores in the walls.