Heavy metals are increasingly found in industrial stormwater. Metals are used extensively in industrial processes across a range of sectors, including aerospace, petrochemicals, mining, papermaking and textiles, and it is inevitable that these metals find their way into surface water runoff.

Heavy metals that are not captured and removed from industrial water pass into the environment, where they are damaging to plants, animals and ecosystems. They do not biodegrade, they may accumulate within the food chain, and some may also be carcinogenic.

The presence of heavy metals in effluent is a headache that industrial businesses must address, as failure to treat these materials could have significant financial, legal and environmental implications.

Fortunately a range of technologies and techniques have been developed that can address heavy metals in industrial stormwater. Talk to our experts to find out how you could benefit from them.

The heavy metals most commonly found in industrial water are:

• Zinc, Zn
• Copper, Cu
• Mercury, Hg
• Lead, Pb
• Nickel, Ni
• Cadmium, Cd
• Chromium, Cr
• Arsenic, As

Although these metals are likely to be the most common, other metals such as iron, manganese, silver and cobalt may also be present.

Metal ions may be dissolved, or bound to sediment and other solid particles that are suspended in the wastewater.

The composition and concentrations of the various metal ions present vary from industry to industry.

The primary impact that heavy metals have on industrial stormwater is in placing a greater financial and/or treatment burden on the facility in question.

Discharging effluent containing heavy metals not only damages the environment, but it also results in higher surcharge costs for the business. As such, as environmental regulations become more and more stringent, there is both a financial and an ethical incentive for businesses to seriously tackle industrial heavy metal in water.

One further potential secondary impact is that the presence of heavy metals in water limits or prevents recycling and re-use of that water. Loss of this source of water for activities such as cooling or clean-in-place will adversely affect the overall operational efficiency of a plant.

There are a range of technologies and techniques that may be used to capture and remove heavy metals from industrial stormwater. Established approaches include chemical precipitation, flocculation, coagulation, flotation, adsorption, ion exchange, and electrochemical deposition.

The most appropriate approach for metals removal will depend on a number of site- and process-specific factors, including cost-effectiveness and economic feasibility, concentration of metal ions, pH level, desired removal efficiency and environmental impact. Speak to an expert about which approach would be most appropriate for your facility.