Treatment of Pharmaceutical Waste Water by Hybrid Separation Processes
Advancing the chemical engineering fundamentals
Membranes and Membrane Science (T2-8P)
Keywords: waste water, hybrid processes, nanofiltration, reverse osmosis, chemical oxygen demand
Latest environmental regulations urge industrial companies to apply preventive environmental politics and to pay more attention to observe prescriptions than earlier. Extensive research is carried out in developing applied environmental management policies. Usually, there are many engineering options for achieving the policies. Hybrid processes including distillation followed by membrane techniques are promising alternatives for industrial waste water treatment, therefore more and more experiments are performed to support their industrial application.
The aim of our study is to give an optional treatment method for a given pharmaceutical waste water. Membrane techniques have the advantage not needing any other chemicals for the separation. Attaining the membrane separation a pre-treatment of the waste water is needed to avoid the damages of membranes. In this study the treatment of pharmaceutical waste water by hybrid processes is presented. The volatile organic compounds (namely ethanol and toluene which damage the membranes) are removed first by distillation. The pre-treated waste water is still containing organic compounds and salts, therefore has high chemical oxygen demand and high conductivity. The chemical oxygen demand and the conductivity of the pre-treated waste water are reduced by using nanofiltration and reverse osmosis. Emphasis is given to the membrane separations. Cross-flow filtration is executed. Membranes experiments are carried out using the 3DTA test-membrane apparatus using four hydrophilic membranes (two nanofiltration and two reverse osmosis membranes). Measurements at different pressures are performed in case of each membrane. Also a two-stage filtration (nanofiltration followed by reverse osmosis) is carried out. Permeate properties including permeate flux, concentration of the main component, temperature, pH, conductivity and chemical oxygen demand are measured. The effect of the operating pressure on the permeate flux is examined and evaluated. The performance of nanofiltration and reverse osmosis is compared. It is experienced that hybrid separation processes (distillation followed by membrane separation) can be successfully used for the treatment of pharmaceutical waste waters. Nanofiltration and reverse osmosis prove to be effective in further reducing the chemical oxygen demand of pharmaceutical waste waters.
See the full pdf manuscript of the abstract.
Presented Tuesday 18, 13:30 to 15:00, in session Membranes and Membrane Science (T2-8P).
