Removal of Selected Pharmaceutical Compounds Through Vertical Flow Constructed Wetland

Abstract

The usage of hundreds of synthetic organic compounds has transformed life. This includes pharmaceuticals and personal care products (PPCPs). These compounds are now abundant in water systems due to their widespread use, fast growth and ease of access. Pharmaceutical and PPCPs pollutants are increasingly brought into waterways by wastewater treatment plants. The cost-effectiveness of constructed wetlands (CWs) in removing the chemical pollutants (PPCPs) from wastewater treatment plant (WWTP) effluents has attracted considerable interest. Therefore, the primary objective of this study was to design vertical flow constructed wetlands (VF-CWs) for eliminating specific pharmaceutical chemicals at different concentrations and retention time. This research aimed to examine the effectiveness of VF-CWs in reducing pharmaceutical contaminants. The study utilized Ciprofloxacin, Ibroufen, Paracetamol and Cefixime for the preparation of the synthetic wastewater. Three distinct types of CWs were constructed, first planted with Typha Australis, second with beds and third planted with Water Hyacinth. A total of 3 batches were run and the sampling of each batch was conducted every 48 hours. The results showed significant reductions with Typha Australis in Batch 1, reducing 65.61% COD, and 67.1% BOD. Batch 2 reduced 56.5% COD and 52.3% BOD. In Batch 3, 47.0% COD and 53.4% BOD were reduced. The Water Hyacinth system also performed well in all batches. It reduced 44.5% COD and 51.4% BOD in Batch 1. Batch 2 lowered COD to 44.5% and BOD to 51.9%. Batch 3 lowered COD to 44.5% and BOD to 51.4%. With comparatively lower reduction rates across all 3 batches, the Beds system showed satisfactory treatment as well, Batch 1 lowered COD to 58.2% and BOD to 56.6%. In batch 2, COD dropped to 55.6% and BOD to 52.10% whereas in Batch 3 COD dropped to 41.5% and BOD to 50.2%. HPLC analysis highlighted the removal of pharmaceutical contaminants in three batches. The Typha Australis system exhibited the best removal rate of 42.8%, Water Hyacinth system 36.3% and conversely, the Beds system exhibited 32.1% in batch 1. The Typha Australis system removed drugs with best removal rates while Water Hyacinth and beds systems also showed considerable results. The first batch had better treatment results than the other two. Further research is needed to improve removal strategies and sustain wetland systems.