This document summarizes the key steps and processes involved in sewage treatment. It first defines sewage as household liquid waste from sources like toilets and sinks that is collected in sewers, sometimes also including industrial waste. The treatment process involves preliminary, primary, and secondary stages to remove solids and organic matter through physical, chemical, and biological processes like sedimentation and activated sludge. Tertiary treatment provides a final polishing step to further improve water quality before discharge through additional filtration or nutrient removal.

1. ENVIRONMENTAL CONTROL
& MANAGEMENT
Muhd Hasyir Mirza b. Dazirman
SEWAGE TREATMENT

2. INTRODUCTION OF SEWAGE TREATMENT
- Process of removing contaminants
from wastewater, primarily from
household sewage.
 Physical process
 Chemical process
 Biological process
- Sewage treatment may also be
referred to as wastewater treatment.

4. SEWAGE
Sewage is generated by:
It includes household waste liquid from toilets, baths, showers, kitchens,
and sinks draining into sewers. In many areas, sewage also includes liquid
waste from industry and commerce.

5. PROCESS STEPS
Sewage treatment involved three stages:
• Primary
• Secondary
• Tertiary

6. PRELIMINARY TREATMENT
• Physically process
• Use screens, grit removal and settling tanks.
• To remove large solids, dead animals, rocks,
sticks, tree limbs, leaves, branches, and
other large objects. from enter the
treatment line.

7. PRIMARY TREATMENT
• Consists of temporarily holding the sewage in a
quiescent basin
• Heavy solids can settle to the bottom while oil, grease
and lighter solids float to the surface.
• The settled and floating materials are removed and the
remaining liquid may be discharged or subjected to
secondary treatment.

8. SECONDARY TREATMENT
 To remove the residual organics and suspended solids.
 Degrading most of the organic matter – Aerobic biological treatment
 Removed during secondary sedimentation is normally combined with primary
sludge for sludge processing.
 Process include:
- Activated sludge
- Tricking filters
- Rotating biological contactor

9. TERTIARY TREATMENT
 To provide a final treatment stage to further improve the effluent quality
before it is discharged to the receiving environment
 Process includes:
- Filtration
- Nitrogen removal
- Biological nutrient removal