Home
Lecture
Quiz
Design Example

Water Treatment
The raw sewage must be treated before it is discharged into the river stream. The extent of treatment required to be given depends not only upon the characteristics and quality of the sewage but also upon the source of disposal, its quality and capacity to tolerate the impurities present in the sewage effluents without itself getting potentially polluted.

Lecture 5: Preliminary Treatment: Silt Excluder Design Lecture 7: Coagulation - Flocculation Theory; Lecture 8: Rapid Mixing, Coagulation - Flocculation; Lecture 9: Coagulation - Flocculation Lecture 6: Sedimentation Tank Design Lecture 10: Filtration Theory; Lecture 11: Rapid Sand Filtration Lecture 12: Disinfection Lecture 13: Treatment Plant Siting and Hydraulics Lecture 6: Sedimentation Tank Design Lecture 1: Raw Water Source and Quality Lecture 5: Preliminary Treatment: Silt Excluder Design Lecture 7: Coagulation - Flocculation Theory; Lecture 8: Rapid Mixing, Coagulation - Flocculation; Lecture 9: Coagulation - Flocculation Lecture 6: Sedimentation Tank Design Lecture 10: Filtration Theory; Lecture 11: Rapid Sand Filtration Lecture 12: Disinfection Lecture 13: Treatment Plant Siting and Hydraulics Lecture 6: Sedimentation Tank Design Lecture 1: Raw Water Source and Quality
  The layout of conventional wastewater treatment plant is as follows:

Lecture 21: Bar Rack/Screens and Equalization Tank Design; Lecture 22: Grit Chamber and Primary Sedimentation Tank Design Lecture 22: Grit Chamber and Primary Sedimentation Tank Design Lecture 23: Fundamentals of Applied Microbiology; Lecture 24: Activated Sludge Process Description; Lecture 25: Design of Activated Sludge Systems; Lecture 26: Design of Activated Sludge Systems; Lecture 27: Aerator Design for Activated Sludge Process; Lecture 28: Trickling Filter Fundamentals and Design; Lecture 29: Other Aerobic Treatment Systems; Lecture 30: Anaerobic Treatment Fundamentals; Lecture 31: Design of Anaerobic Reactors; Lecture 32: Design of UASB Reactors Lecture 33: Nitrification: Process Description and Design; Lecture 34: Denitrification: Process Description and Design; Lecture 35: Phosphorus Removal and Other Advanced Treatment Lecture 17: Wastewater Quality and Quantity Estimation Lecture 38: Siting and Hydraulics of Wastewater Treatment Plants

 

Indian Standards for discharge of sewage in surface waters are given in the table below.

Indian Standards for Discharge of Sewage in Surface Waters

Characteristic of the Effluent
Tolerance limit for Discharge of Sewage in Suface Water Sources
BOD5
20 mg/L
TSS
30 mg/L

The unit operations and processes commonly employed in domestic wastewater treatment, their functions and units used to achieve these functions are given in the following table:

Unit Operations/Processes, Their Functions and Units Used for Domestic Wastewater Treatment

Unit Operations/Processes
Functions
Treatment Devices
Screening Removal of large floating, suspended and settleable solids Bar racks and screens of various description
Grit Removal Removal of inorganic suspended solids Grit chamber
Primary Sedimentation Removal of organic/inorganic settleable solids Primary sedimentation tank
Aerobic Biological Suspended Growth Process Conversion of colloidal, dissolved and residual suspended organic matter into settleable biofloc and stable inorganics Activated sludge process units and its modifications, Waste stabilisation ponds, Aerated lagoons
Aerobic Biological Attached Growth Process same as above Trickling filter, Rotating biological contactor
Anaerobic biological growth processes Conversion of organic matter into CH4 & CO2 and relatively stable organic residue Anaerobic filter, Fluid bed submerged media anaerobic reactor, Upflow anaerobic sludge blanket reactor, Anaerobic rotating biological contactor
Anaerobic Stabilization of Organic Sludges same as above Anaerobic digestor
 

Lecture 5: Preliminary Treatment: Silt Excluder Design Lecture 7: Coagulation - Flocculation Theory; Lecture 8: Rapid Mixing, Coagulation - Flocculation; Lecture 9: Coagulation - Flocculation Lecture 6: Sedimentation Tank Design Lecture 10: Filtration Theory; Lecture 11: Rapid Sand Filtration Lecture 12: Disinfection Lecture 13: Treatment Plant Siting and Hydraulics Lecture 6: Sedimentation Tank Design Lecture 1: Raw Water Source and Quality