Illustrated series

Water treatment principles, illustrated

The series is organized into seven sections. Every guide starts with a realistic system or site view, then moves through the governing mechanism, material and energy paths, key variables, and abnormal conditions. The imagery contains no fixed-language labels; the Chinese, English, Vietnamese and Arabic explanations switch with the site.

How does reverse osmosis remove salt?Membranes & separation

How does reverse osmosis remove salt?

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What is the difference between UF, NF and RO?Membranes & separation

What is the difference between UF, NF and RO?

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Why can hollow-fiber UF membranes be backwashed?Membranes & separation

Why can hollow-fiber UF membranes be backwashed?

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How does an MBR separate sludge from water?Membranes & separation

How does an MBR separate sludge from water?

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How does EDI continuously produce high-purity water?Membranes & separation

How does EDI continuously produce high-purity water?

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How does electrodialysis drive ions in a chosen direction?Membranes & separation

How does electrodialysis drive ions in a chosen direction?

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Why does residual chlorine damage RO membranes?Membranes & separation

Why does residual chlorine damage RO membranes?

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How can membrane fouling, scaling and damage be distinguished?Membranes & separation

How can membrane fouling, scaling and damage be distinguished?

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What is the difference between COD and BOD?Biological treatment

What is the difference between COD and BOD?

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How do microorganisms clean wastewater?Biological treatment

How do microorganisms clean wastewater?

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How is ammonia converted step by step into nitrate?Biological treatment

How is ammonia converted step by step into nitrate?

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Why is denitrification needed to remove total nitrogen?Biological treatment

Why is denitrification needed to remove total nitrogen?

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How do microorganisms release and take up phosphorus?Biological treatment

How do microorganisms release and take up phosphorus?

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What happens in the three zones of an A2O process?Biological treatment

What happens in the three zones of an A2O process?

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How does an SBR perform several stages in one tank?Biological treatment

How does an SBR perform several stages in one tank?

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Why does sludge settle in a secondary clarifier, and why can it wash out?Biological treatment

Why does sludge settle in a secondary clarifier, and why can it wash out?

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How does coagulation make fine colloids form flocs?Physical & chemical treatment

How does coagulation make fine colloids form flocs?

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What do PAC and PAM each do during coagulation?Physical & chemical treatment

What do PAC and PAM each do during coagulation?

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Why is a larger settling tank not always better?Physical & chemical treatment

Why is a larger settling tank not always better?

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How does dissolved-air flotation use microbubbles to remove contaminants?Physical & chemical treatment

How does dissolved-air flotation use microbubbles to remove contaminants?

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How does a sand filter capture particles and backwash itself?Physical & chemical treatment

How does a sand filter capture particles and backwash itself?

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How does chemical precipitation remove heavy metals?Physical & chemical treatment

How does chemical precipitation remove heavy metals?

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How does ion-exchange resin soften water and regenerate?Physical & chemical treatment

How does ion-exchange resin soften water and regenerate?

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Why is a high-rate clarifier faster than a conventional clarifier?Physical & chemical treatment

Why is a high-rate clarifier faster than a conventional clarifier?

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How does chlorine inactivate microorganisms in water?Disinfection, oxidation & micropollutants

How does chlorine inactivate microorganisms in water?

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Why is sodium hypochlorite useful but demanding to handle?Disinfection, oxidation & micropollutants

Why is sodium hypochlorite useful but demanding to handle?

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How does chlorine dioxide disinfection differ from chlorine?Disinfection, oxidation & micropollutants

How does chlorine dioxide disinfection differ from chlorine?

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How does UV light damage microbial DNA?Disinfection, oxidation & micropollutants

How does UV light damage microbial DNA?

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Why is ozone such a strong oxidant?Disinfection, oxidation & micropollutants

Why is ozone such a strong oxidant?

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How do advanced oxidation processes generate hydroxyl radicals?Disinfection, oxidation & micropollutants

How do advanced oxidation processes generate hydroxyl radicals?

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How does activated carbon adsorb odors and micropollutants?Disinfection, oxidation & micropollutants

How does activated carbon adsorb odors and micropollutants?

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Why are PFAS called forever chemicals?Disinfection, oxidation & micropollutants

Why are PFAS called forever chemicals?

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How does a multistage centrifugal pump build pressure stage by stage?Equipment cutaways

How does a multistage centrifugal pump build pressure stage by stage?

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What is inside an RO pressure vessel?Equipment cutaways

What is inside an RO pressure vessel?

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How does an automatic control valve switch between filtration and backwash?Equipment cutaways

How does an automatic control valve switch between filtration and backwash?

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How does a metering pump dose chemicals precisely?Equipment cutaways

How does a metering pump dose chemicals precisely?

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How do a Roots blower and diffusers transfer oxygen into water?Equipment cutaways

How do a Roots blower and diffusers transfer oxygen into water?

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How does a plate-and-frame filter press turn sludge into cake?Equipment cutaways

How does a plate-and-frame filter press turn sludge into cake?

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How does a centrifuge use rotation to separate sludge and water?Equipment cutaways

How does a centrifuge use rotation to separate sludge and water?

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How does a desalination energy-recovery device work?Equipment cutaways

How does a desalination energy-recovery device work?

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Why does a cooling tower make circulating water saltier?Industrial water systems

Why does a cooling tower make circulating water saltier?

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What do cycles of concentration mean in cooling water?Industrial water systems

What do cycles of concentration mean in cooling water?

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Why do scaling, corrosion and biofouling often occur together?Industrial water systems

Why do scaling, corrosion and biofouling often occur together?

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Why must boiler water be deaerated, softened and pH-controlled?Industrial water systems

Why must boiler water be deaerated, softened and pH-controlled?

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How do boiler blowdown control and condensate recovery save water and energy?Industrial water systems

How do boiler blowdown control and condensate recovery save water and energy?

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Why do ultrapure-water systems often combine UF, RO and EDI?Industrial water systems

Why do ultrapure-water systems often combine UF, RO and EDI?

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Where does a seawater desalination system use most of its energy?Industrial water systems

Where does a seawater desalination system use most of its energy?

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How does a ZLD system progress from membrane concentration to crystallization?Industrial water systems

How does a ZLD system progress from membrane concentration to crystallization?

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What do pressure, flow and conductivity reveal in an RO system?Operations & diagnostics

What do pressure, flow and conductivity reveal in an RO system?

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What does rising RO stage differential pressure usually mean?Operations & diagnostics

What does rising RO stage differential pressure usually mean?

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Does high permeate conductivity always mean membrane damage?Operations & diagnostics

Does high permeate conductivity always mean membrane damage?

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What do acid and caustic CIP cleaning remove?Operations & diagnostics

What do acid and caustic CIP cleaning remove?

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How should DO, ORP, MLSS and SVI be interpreted together?Operations & diagnostics

How should DO, ORP, MLSS and SVI be interpreted together?

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How can sludge bulking be distinguished from clarifier washout?Operations & diagnostics

How can sludge bulking be distinguished from clarifier washout?

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How does a variable-frequency drive reduce pump energy use?Operations & diagnostics

How does a variable-frequency drive reduce pump energy use?

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How are water balance, recovery and concentration factor calculated?Operations & diagnostics

How are water balance, recovery and concentration factor calculated?

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