From traditional wastewater treatment to zero-discharge strategy
Traditional end-of-pipe solutions for dealing with effluents coming out of the production plant have being gradually substituted for an increasingly decentralised approach to treat selected wastewater streams in the most effective and economically sound way. Moreover, additional goals like reducing overall effluent emissions by reusing treated wastewater towards zero-discharge strategies or minimising waste generation and disposal costs have been gradually incorporated to a growingly holistic water and wastewater management approach. The future of industrial wastewater treatment has mainly two:
- Both the monitoring and abatement of trace pollutants, as prioritised in the Annex X of the EU directive 2000/60/EC [EU 2000], and additional dangerous trace contaminants [LANUV 2007].
- Further development of existing and new wastewater treatment technologies in order to minimise costs and optimise resource consumption. [Krause etal. 2011] [Rosenwinkel et al. 2011]
As in many other industrial branches, production managers at the pharmaceutical industry are adopting an increasingly decentralised approach when dealing with well characterised wastewater streams.
The removal efficiency of PPCPs (Pharmaceuticals and Personal Care Products), PhACs (Pharmaceutical Active Components) and EDCs (Endocrine Disruptive Components) has been tested for many different technologies which are available for the last decades. Results vary from zero abatement effectivity as shown by traditional coagulation and flocculation processes (alum & ferric chloride) to high and very high removal rates as those achieved by active carbon filtration, biological degradation, membrane filtration technology (e.g. reverse osmosis, ultrafiltration at membrane biological reactors, etc.), oxidation technologies combining different available AOPs (Advanced Oxidation Processes) like ozonation1, hydrogen peroxide with radiation from UV light, etc. [Khiari 2007] [Ternes et al. 2004]
This article aims to present some examples of modern effluent treatment solutions which have been realised at research-based pharmaceutical companies, where effluents could be specifically treated in order to:
- reduce the overall footprint of the wastewater treatment plant by implementing state-of-the-art MBR technology and/or a modular design approach;
- abate trace elements by separating and concentrating them to minimise costs of external disposal (e.g. reverse osmosis and vacuum distillation);
- inactivate streams containing biologically active ingredients (e.g. hormones, antigens, etc.) by means of thermal sterilisation technology;
- eliminate pharmaceuticals implementing advanced oxidation processes (e.g. ozonation);
- or generate green energy (biogas) from digested organic matter (COD) implementing anaerobic treatment technology.