Removing APIs & EDCs from Wastewater

The most obvious route is through consumption by humans and animals, prescribed by medical professionals or veterinarians. When taken, only a certain amount of any dose is metabolised, so the rest passes into the sewage system (or in the case of animals, into groundwater and eventually into the leachate.)
Regular wastewater treatment plants (WWTPs) are not designed to remove APIs, so over the last 80-odd years, their concentrations have been building up in what we used to refer to as ‘clean’ water.
Worldwide, the problem has gotten worse in the last 20-30 years with a growth in the use of antibiotics in countries with a less regulated approach to medicines, especially when the manufacturers’ recommended dosage and course length may not have been followed.

The second route is the improper disposal of medications. Very few members of the public are aware of the pharmacological risks of throwing away unwanted prescription drugs. Many older people probably consider it a safety issue solely to ensure small children don’t inadvertently consume them. In the UK, this dates back to Government public information broadcasts from the 1970s showing just that.
But from unauthorised dumping of expired products to profiteering in the grey market (and even the illegal street trading of in-demand drugs) there are many additional ways where large amounts of antibiotics can find their way into watercourses.

The third route and where Arvia can help is with discharges directly from pharmaceutical manufacturing plants. Whilst the pollutant levels will normally be within agreed limits and generally pharma companies do a good job of treating their wastewater, regulations are not consistent across the world. In addition, with the rise of AMR, it’s quite likely that the public mood is about to change.
Nowadays, many companies pay to discharge at a certain concentration. However we suspect discharge limits could be lowered soon in the light of public, investor, or government pressure due to AMR. And this could even be whether or not the company in question is discharging APIs that have been proven to be harmful. Certainly, the historic higher levels of API discharge from antibiotic manufacturing in the past are now believed to endanger aquatic life downstream.

Ozone is a powerful oxidant used to break down the recalcitrant compounds but it comes with significant COSHH implications and maintenance requirements to keep it working as planned.
Nevertheless, it is a commonly used tertiary treatment in many pharmaceutical plants for API removal.

GAC (granular activated carbon) is an established method of treatment that takes advantage of the massive surface area of the active media. APIs are adsorbed onto its surface. But to get to that stage, the activated carbon first has to be produced – an environmentally-costly process, involving burning material like coconut shells, coal, peat or wood.
From an environmental point of view it is wasteful, as the spent carbon has to be removed and then either re-processed or sent to landfill. Replenishment of the medium will inevitably disrupt production processes.

Another alternative are systems which use oxidation. The effect of chemical dosing is stimulated by electricity. The electricity generates hydroxyl radicals which once they have ‘bumped into’ the API, will oxidise it by breaking them down into gas and water. This method can be very effective but dependent on the other pollutants in the wastewater, can use a lot of power.

Nyex Rosalox™ is a revolutionary water treatment process from Arvia Technologies. It is a combination of two of the most successful methods discussed above – adsorption and electrochemical oxidation. To that, it adds the unique properties of our Nyex™ Media – an adsorptive media that regenerates at the same time as it adsorbs the organics it is oxidising.
A product of over 30 year’s continuous research by Dr Nigel Brown of Manchester University in the UK, the latest Nyex ™ tertiary water treatment systems are designed specially to treat recalcitrant organics and can be used in a variety of situations in a wide variety of industries.