Quick answer: A practical wastewater-treatment decision starts with defining the failure mode, then checks pH, COD, ammonia, sludge condition, and process interaction before changing chemistry or operation.

Classification and application of conventional coagulation agents

1. Iron salt, aluminum salt and their compound medicaments

Iron salt: polymeric ferric sulfate (PFS), ferrous sulfate

Aluminum salt: polyaluminum chloride (PAC), aluminum sulfate, alkali aluminum

Compound medicine: compound aluminum iron

Application effects: pretreatment to remove SS, decolorization, and degreasing; advanced treatment to remove COD and phosphorus; play different roles for different industries.

2. To adjust the PH value of medicament flake caustic soda, quicklime, hydrated lime, compound alkali, and sulfuric acid.
3. Flocculant

Anionic, cationic, non-ionic PAM

Application effect: Choose according to the electric charge of the flocs in the water, the content of organic matter, and the PH value.

Professional medicine and application

1. Decolorization: conventional coagulation agents (such as ferrous sulfate, polyferric sulfate, etc.), organic decolorizers, are often used in printing and dyeing wastewater and leather wastewater;
2. In addition to COD: COD remover, Fenton combination agent, mostly used for the advanced treatment of the end; it is widely used in papermaking, printing and dyeing, electroplating, and circuit board industries;
3. Phosphorus removal: Phosphorus removal agent, other iron salt, aluminum salt, calcium salt; it is widely used in urban sewage treatment plants and metal surface oxidation plants;
4. Removal of ammonia nitrogen: ammonia nitrogen remover, mainly electroplating, and more applications in the circuit board industry;
5. In addition to complexed heavy metals: decomplexing agent, sodium sulfide, recapture agent; more applications in electroplating plants and circuit boards;
6. Fluoride removal: fluoride removal agent, calcium salt, aluminum sulfate; electroplating plant

Introduction to other products

1. Bio-activated bacteria

Including obligate strains for ammonia removal and COD removal, it is suitable for biological activation of sewage treatment facilities such as leather making, printing and dyeing, urban sewage treatment plants, food plants, etc.; the function mainly includes the formation of dominant bacteria and promotes the growth and reproduction of microorganisms.

2. Sludge water reducer

Modification and conditioning of the sludge by the water reducing agent improves the dewatering performance of the sludge to release more attached water and bound water. After dewatering, the moisture content of the sludge is reduced to less than 60% for subsequent advanced treatment. And resource utilization. It is suitable for the deep dewatering of sludge in urban sewage plants, printing and dyeing, papermaking, sludge centralized disposal centers and other enterprises.

3. Photocatalytic equipment

It is suitable for the decolorization, COD removal, and partial phosphorus removal of high-concentration refractory wastewater; it has high investment and operating costs, and is more suitable for small-volume wastewater treatment.

4. Electro-flocculation equipment is suitable for electroplating and circuit board enterprises to remove complexed heavy metals, such as chemical nickel, and also suitable for removing partial phosphorus; investment and operating costs are high, and it is more suitable for sewage treatment with small amounts of water.

A practical process checklist for wastewater and sewage-treatment topics

Most wastewater-treatment problems are system problems. Teams usually get a better result when they define the process stage and water-quality target first, then review biological, chemical, and operational factors together before making a plant-scale correction.

• Start from the process stage: pretreatment, biological treatment, sludge handling, and polishing steps can point to very different root causes.
• Check the core water-quality data together: pH, COD, nitrogen, salinity, sludge condition, and dissolved oxygen often need to be read as one picture.
• Review compliance and operability at the same time: the quickest local fix can still be the wrong commercial move if it destabilizes another part of the plant.
• Use pilot or staged validation where possible: wastewater systems often respond differently at scale than they do in simplified bench assumptions.

Recommended product references

• CHLUMIAF 094: A balanced defoamer reference for waterborne coatings and many general foam-control screens.
• CHLUMIAF 3037: A stronger process-defoaming option when persistent foam survives harsher conditions.
• CHLUMIWE 3280: A strong wetting-agent reference for inks, coatings, and difficult substrate wetting.
• CHLUMIWE 3071: Useful when organosilicone wetting support is needed in a broad application screen.

FAQ for buyers and formulators

Why do many wastewater problems resist one-step fixes?
Because the visible symptom is often created by several interacting process variables rather than one isolated cause.

Should operational changes be evaluated only by one output indicator?
Usually no. A stable treatment decision should consider process balance, compliance, sludge behavior, and the effect on downstream steps as well.