Date of Award


Document Type

Master Thesis

Degree Name

Masters of Science (Research)


Clean Technology Centre

First Advisor

Mr. Noel Duffy


The biodegradation of a selected active pharmaceutical ingredient (API) during wastewater treatment in a membrane bioreactor (MBR) was examined experimentally. A comparison study was conducted by operating a conventional activated sludge (CAS) pilot plant in parallel to the MBR. The MBR was operated under varying conditions of pH (pH6 and pH8), MLSS (6g/L and l0g/L) and SRT (20 days and 30 days) according to a full factorial design of experiments. In the CAS, pH and SRT were altered as above but MLSS was maintained at 3-4g/L. Comparable average API removal results of 95.5% and 95.7% were obtained for the MBR and CAS, respectively. The effluent produced by the MBR surpassed the CAS in terms of the quality parameters: COD removal (MBR-97.97%, CAS-93.57%), total phosphorous (TP) removal (MBR- 88.11%, CAS-79.99%) and total suspended solids (MBR-1.08mg/L, CAS-62.36mg/L). Statistical analysis showed that on an individual basis, high levels of each of the independent variables resulted in greatest removals of influent API. Following successful removal of the target API, it is proposed that previously incinerated waste streams (approximately 156m^ per annum) be diverted to the large- scale CAS WWTP in Eli Lilly. This would result in a substantial cost saving in the order of €76,000 per annum as well as reducing the burden on incinerator capacity. A supplementary investigation into wastewater reclamation was conducted. Should a MBR be incorporated into the CAS WWTP, it is proposed that the effluent be reused as incinerator quench water, thus reducing well water extraction by up to 288m3 per day.


The work was conducted in Eli Lilly and the Cork Institute of Technology between October 2006 and July 2008. Provision of funding for the project by Eli Lilly.

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