Studies reveal that more than 80,000 chemicals are being used in producing commercial goods ranging from water bottles, toys to contact lenses. These chemicals find their way into human bodies through different means such as food, air, dust and water. Even though found in trace amounts, they pose serious risk to normal functioning of a human being. One of such chemicals is Bisphenol A (BPA) which is found in more than 90 % of the Americans .
BPA is one of the highest produced synthetic chemicals used in industry since 1960’s . It is a white solid essentially used in the production of polycarbonates and epoxy resins. Polycarbonates and Epoxy resins are widely used as ...view middle of the document...
Wastewater treatment effluents, polycarbonate plastics natural degradation, landfill leachate, Industrial wastewaters are some the ways BPA enter the aquatic system. It was published that BPA concentrations in municipal landfill leachates are as high as 26-8400 µg/dm3 . They are present in the influents as well as in the effluents of the WWTPs. Incomplete degradation and removal of BPA at WWTP make it one of the principal sources of BPA pollution. Earlier, dilution of wastewater treatment effluents into the rivers used to take care of such micro pollutants. But, due to recent developments which increased water demands and reduced the streams flow, dilution is no longer a feasible option . This paved the way to look into treatment processes which would reduce the micro pollutants concentrations in the waste water effluents. Most of the conventional wastewater treatment plants don’t attend to satisfactory levels of BPA removal. However, treatment plants with tertiary treatment process aids BPA removal.
This paper emphasizes on the different treatment processes available in the treatment of Bisphenol A. It compares them based on the relative advantages and disadvantages.
2. TREATMENT PROCESSES
According to EPA, the conventional treatment (secondary) processes are not successful in reducing the effluent BPA concentrations to acceptable levels. Hence, high concentrations of the Bisphenol A contaminant are found in the effluents of the treatment plants. Several treatment processes have been proposed to removal of BPA from drinking and waste waters. After extensive research the following treatment processes have been proposed which showed great rates of removal of Bisphenol A. They are:
2. Activated Carbon
3. Advanced Oxidation Process ( Ozonation)
It must be noted that these processes serve as an extension to the conventional wastewater treatment systems adopted. The act as the tertiary treatment processes in the system.
NF membranes were primarily used for the removal of bacteria and viruses in the Pre-Treatment, Treatment, and Purification processes. However, studies conducted to acquire a better understanding of the transfer mechanisms of BPA through an NF membrane indicate that they contribute to a considerable removal of the chemical. Nanofiltration depends on the capability of membranes to segregate the particles or species in a solution based on their physical sizes.
Different types of membranes are being used by the wastewater treatment industry. Some of them include microfiltration (MF), ultra filtration (UF), reverse osmosis (RO), and nanofiltration (NF) membranes. Nanofiltration membranes are comparatively new which are also known as called “loose” Reverse Osmosis membranes. NF membranes are porous with an average pore size of ten angstroms or lesser. Their performance lies in between that of Ultra Filtration and Reverse Osmosis membranes . Cellulose acetate...