Learn Wastewater Process Control
How each part of the plant works and what the operator controls.
Plain language explanations of each part of a wastewater plant, written for operators. Every page has original diagrams, White River WRRF examples and links to the matching calculators and troubleshooting guides.
Activated Sludge Basics
How the activated sludge process works: aeration basin, secondary clarifier, RAS and WAS, and the key control numbers (MLSS, SRT, F/M, SVI, DO)...
Biological Treatment
The microorganisms behind activated sludge: heterotrophs, nitrifiers, protozoa, floc formation, filaments and bulking, and what conditions favor...
Nitrification
How nitrification converts ammonia to nitrate, what it needs (oxygen, alkalinity, SRT, temperature), the key stoichiometry, and how operators keep it...
Denitrification
How denitrification converts nitrate to nitrogen gas in anoxic zones, what it needs (no DO, carbon, nitrate), the MLE process, alkalinity and oxygen...
Biological Nutrient Removal (BNR)
An operator overview of BNR: nitrogen removal with anoxic zones, enhanced biological phosphorus removal with anaerobic zones, common configurations...
Secondary Clarifiers
How secondary clarifiers separate mixed liquor: zones, surface overflow rate, solids loading rate, sludge blanket control, state point analysis and...
RAS and WAS
Return activated sludge and waste activated sludge explained: what each does, how to calculate RAS flow and WAS rate, mass balance, and the daily...
Aeration
How aeration systems supply oxygen and mixing: fine bubble and mechanical aeration, oxygen transfer, AOR and SOR, blowers, DO control and energy...
Microscopy for Operators
Why activated sludge microscopy matters, what operators look for (floc, filaments, protozoa, small animals), and how to build a simple daily...
Preliminary Treatment
Screening, grit removal and flow measurement at the headworks, and why they matter to the activated sludge process...
Primary Treatment
How primary clarifiers remove settleable solids and part of the BOD, key loading and detention numbers, and their effect on the activated sludge...
Disinfection
How plants disinfect secondary effluent with chlorine or UV, the effect of effluent TSS and ammonia on disinfection, and key dose and contact...
Solids Handling
What happens to WAS and primary sludge: thickening, anaerobic digestion, dewatering and biosolids, and how return streams affect the activated sludge...
Interactive Process Map
Click any part of the plant to jump to its page.