The selection of coagulant determines the quality of the wastewater

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The coagulation process is important in order to ensure that the wastewater that is discharged from your company or wastewater plant is of acceptable quality.

Coagulation is a chemical process involving charge neutralization, which causes the colloidal particles to accumulate in microflocs.

Coagulants are used as the first part of the precipitation process. They react with dissolved and suspended substances and form these microflocs. With the use of flocculants (polymers), the microflocs can be gathered into large flocs, which can be separated from the water phase and dewatered.


Coagulants are divided into two main groups: organic and inorganic coagulants. Special mixtures of inorganic and organic coagulants are gaining more and more ground, as in some applications they produce a better result than standard coagulants do individually.

Inorganic coagulants, mostly metal salts, are used to treat wastewater and drinking water worldwide. The most common coagulants used when treating wastewater are ferric chloride and polyaluminium chloride, but sodium aluminate (NaAIO2) is also widely used. For drinking water, aluminum based coagulants are the most widely used.

Norfloc NF1, AluSAL, AluACH and AluPAC are the clear choices of coagulants for precipitation of suspended solids and for removal of phosphorous. The uniformity of the products ensures an excellent result in the flotation or sedimentation process and ensures high water purity.


Organic coagulants include products that can be based on amines, polyDADMAC or tannins. Amines and polyDADMAC are the most commonly used. They are widely used in the industry and potable water treatment, where inorganic coagulants do not produce the same result.

Tannin-based products have a more limited use but are an attractive alternative due to their green profile. Today, they are used in the fishing industry in particular.

Our natural polymers are starch based and can be used in separation of water from solids when renewable, bio-based raw material is preferred. Our natural polymers contain no acrylamide and is therefore the optimal natural solution for water treatment.

Special blends of organic and inorganic coagulants are gaining more and more ground as higher demands are placed on the treatment of water and wastewater. These mixtures often generate a much better result than the coagulants do separately.

Most mixtures are based on AluPAC and amines, but products containing iron chloride (either iron (II) or iron (III)) and magnesium also have applications where they generate a noticeable effect.

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Our products

Sodium Aluminate – AluSAL®

AluSAL is produced by reacting alumina hydroxide with sodium hydroxide. Our unique manufacturing process...

Potassium Aluminate – AluPAL®

Excellent coagulation, flotation and sedimentation. Excellent removal of phosphor. Minimal chemical sludge

Poly Aluminium Chloride – AluPAC®

(PAC) Poly Aluminium Chloride – AluPAC is a high purity product with high aluminum content...

Aluminum Chlorohydrate – AluACH®

AluACH is an extremely powerful and versatile product for drinking water and industrial wastewater...

Norfloc NF1

A new inorganic coagulant that optimizes operation and can replace the traditional metal salts

Dosing Systems

Dosing systems of all sizes to liquid polymers, powder-dosing systems, and dosing pumps for coagulation...

Sludge Thickening system

Plug & play systems for dewatering of sludge, using decanter centrifuges. The systems are skid-mounted...


Wastewater treatment

Stay in compliance, stabilize your wastewater treatment plant, and improve your overall operations...

Biological wastewater treatment

Water treatment chemicals and solutions for biological wastewater...

Industrial wastewater treatment

Solution for removing pollutants from the wastewater, making sure that...


Solutions within aquaculture sludge treatment and complete systems for heavy metal removal.