Safer water for future generations

Dr Mikael Khan, Chief Technology Officer at Arvia Technology, a provider of advanced tertiary water and wastewater treatment systems, discusses how technological advancements are enabling the more effective treatment of pharmaceutical waste

Dr Mikael Khan

With national campaigns voicing concerns about the effects of pollution on marine life and the problem of depleting water supplies, concern from the public about the dangers of polluted water has never been more apparent.

There is growing political will in the UK, and across the world, to tackle water pollution of all kinds, and the dangers it poses to the environment and public health. The negative effects on aquatic life exposed to trace amounts of pharmaceuticals in their habitats has been well documented.

Improving efficiencies

Pharmaceuticals are being produced and used at an alarming rate and end up in wastewater through excretion and disposal. The safe disposal of pharmaceutical waste is critical for compliance with regulations and environmental targets, and improving manufacturing efficiencies. For pharmaceuticals to work, they have to remain stable in the human body. This means the compounds in many drugs cannot be broken down and can be challenging to remove from wastewater.

Traditional treatments

Many assume that any process designed to treat wastewater would be inherently beneficial to the environment, but this is not the case. Commonly used tertiary wastewater treatment processes such as ozone with hydrogen peroxide and the Fenton method use large doses of chemicals to eradicate parts per million level organics.

This chemical dosing can produce a toxic sludge that requires transportation and specialist secondary treatment. Unsurprisingly, this ongoing process also comes at a high price. Another factor of concern is that although these traditional wastewater treatment processes can partly remove contaminants, some traces will still be detectable in effluents.

The shortcomings of traditional treatment options have created demand for more economical and environmentally friendly solutions. As a result, solutions now exist that allow pollutants to be selectively targeted without the creation of secondary waste.

Technology is advancing rapidly in this area, meaning that it’s now possible to treat parts per million to parts per billion levels of pollutants. The systems capable of effecting these changes can be easily integrated into an existing treatment train, requiring minimal staff requirements and maintenance. Rather than treating the whole body of water, the chemical industry can now be more selective, targeting problematic compounds with smaller operating costs.

Chemical oxygen demand (COD)

The level of contaminants present in wastewater is gauged by the Chemical Oxygen Demand (COD), which measures organic pollutants in water as milligrams per litre (mg/L) or parts per million (ppm). Current regulations stipulate strict limits of COD for water to be discharged to sewers or the environment, and failure to comply with regulation can result in a loss of permit, operational downtime, limited production volume and severe fines.

Primary and secondary treatment removes around 75–85% of the COD, but the hard-to-treat COD remains. Typically, legislation for COD discharge is from below 120 ppm in the EU.

New technology

The pollution of waterways through pharmaceutical waste should be high on the agenda of pharmaceutical companies across the globe. The damaging effects on aquatic life and wildlife and the potential threat to humans cannot be ignored. Effective wastewater treatment at the source of pollution is the first step in addressing a widespread issue.

There are now state-of-the-art solutions for the reduction of hard-to-treat contaminants from water and wastewater streams. These treatment options will enhance environmental strategies and manufacturing best practice. Policy makers are already taking the right steps; however, the chemical industry must begin to counteract the wider problem through more effective wastewater treatment solutions.

NB: This article will appear in the May 2019 issue of Manufacturing Chemist. A recent digital edition is available here.

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