Gravity Thickening of Sludge
Gravity thickening concentrates sludge solids from 0.5–2% to 4–8% before digestion or dewatering. Learn about tank design, hydraulic loading, mechanical operation, and solids capture…
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Water & wastewater treatment, explained by people who run the plants.
A practical field reference for students and engineers — process theory, plant design, worked examples and the day-to-day judgement that textbooks leave out.
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Nine areas, from raw-water chemistry to full plant design. Each opens a curated set of guides.
66 guides
Sewage Treatment
Primary, secondary and tertiary treatment of municipal and industrial wastewater.
33 guidesWater Treatment
Filtration, coagulation and the unit processes that make water potable.
27 guidesWater
Sources, chemistry and the physical properties behind every process.
16 guidesWater Analysis
Sampling, testing and reading the parameters that define quality.
13 guidesDisinfection
Chlorination, UV and ozone at the final barrier.
9 guidesSoftener
Removing hardness with ion exchange and lime–soda.
6 guidesDesalination
Reverse osmosis and thermal routes to fresh water.
7 guidesCorrosion
Why plant and pipework fail — and how to slow it.
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A rotating selection of articles pulled at random from the library, with brief summaries so you can dive straight into the right guide.
BIOLOGICAL OXYGEN DEMAND
Sewage Water Analysis BOD The presence of free oxygen is necessary for the livelihood of organisms present in the sewage water The aerobic action…
Read article →Water Softener
Lime Processing Water Softener Lime softening water treatment process involves a relatively complicated series of chemical reactions. The goal of all of these reactions…
Read article →Ozonation in Water and Wastewater Treatment
Ozonation is a powerful on-site disinfection method using ozone gas to inactivate pathogens and remove taste, odor, and color from water. It is particularly…
Read article →The treatment train
From raw water to the tap, in six stages
Every plant is a sequence of barriers. Follow the flow — each stage links to the guides that explain it.
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01
Intake & Screening
Raw water enters; bar screens and grit channels remove debris.
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02
Coagulation
Coagulants destabilise fine particles into settleable floc.
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03
Sedimentation
Floc settles out under gravity in clarifiers.
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04
Filtration
Rapid sand and media beds polish the remaining turbidity.
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05
Disinfection
Chlorine, UV or ozone inactivate the remaining pathogens.
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06
Distribution
Treated water is pumped to storage and the network.
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