What is Poly Aluminium Chloride?

Poly Aluminium Chloride (PAC) is most commonly used in the water treatment industry as a coagulant. It is characterised by the degree of basification – the higher this number the higher the polymer content which equals a more efficient product in the clarification of water products.

Other uses of PAC include within the oil and gas industries for oil refining where the product works as an oil-water emulsion destabiliser offering excellent separation performance. In terms of crude oil, any water presence equals a reduced commercial value and higher refining costs, so this product is essential in ensuring optimum efficiency.

PAC is also used in the production of deodorants and anti-perspirant products as the active ingredients that essentially creates a barrier on the skin and helps to reduce levels of sweat.  In the paper and pulp industries It is used as a coagulant in papermill wastewater.

Poly Aluminium Chloride is a highly efficient water treatment chemical where it works as a coagulant to extract and clump together contaminants, colloidal and suspended matter. This results in the formation of floc (flocculation) for removal via filters. The below image showing coagulation in action illustrates this process.

Poly Aluminium Chloride products for use in water treatment are typically characterised by their level of basification (%). Basification is the concentration of hydroxyl groups relative to aluminium ions. The higher the basicity, the lower the aluminium content and therefore the higher performance regarding contaminant removal. This lower rate of aluminium also benefits the process where aluminium residuals are greatly reduced.

Aluminium Sulphate has been a widely used coagulant within the water treatment industry for many years where it is used as a flocculant to remove contaminates, unwanted colours and general turbidity (haze) from water. However, this process leaves behind large traces of aluminium in water supplies which requires further filtration and results in generating vast quantities of sludge-like waste (known as water treatment residuals) which is disposed of at landfill. These disposal costs have a direct impact on the operational costs of water treatment plant so it is beneficial to seek alternatives that reduce this.

Having said that, waste treatment residuals do possess many physical and chemical properties that could also lend to them being re-used for a more sustainable purpose including use in construction materials and even soil nutrients however there are well documented concerns regarding aluminium toxicity in soil and damaging implications for ecosystems which limit this approach.

Poly Aluminium Chloride on the other hand, has been developed as an alternative. PAC hydrolyses with greater ease, obtains better coagulation, and rapidly forms flocs making this a much more efficient product. It also possesses lower doses of aluminium therefore leaving significantly fewer aluminium residuals and sludge waste product.

Monarch Chemicals are a leading UK supplier of Poly Aluminium Chloride distributing this material nationwide a wide variety of packaging options including poly, drum, IBC and bulk tank. For more information or to discuss your requirements please visit the Poly Aluminium Chloride product page