Fate of microplastics in wastewater treatment plant

Plastics are used in the production of a wide range of products due to their properties. The increase in plastic consumption every year brings with it plastic pollution. Particles called microplastics (MP), which are formed as a result of the degradation of plastics by environmental processes, are found in various environmental environments such as sea, lake, river, atmosphere and soil. Studies have proven that Wastewater Treatment Plants (WWTP) are an important source of point MP for aquatic and terrestrial environments Despite the high removal efficiency of MPs in WWTP, there is a large amount of release based on the amount of effluent given to the receiving environment. With this study, MP removal efficiency was investigated in the samples taken from different units and at different periods from the urban WWTP located in the west of Bursa. First of all, MPs were classified as shape, color, size and counted using a stereo microscope. Then, polymer types were determined by ATR-FTIR spectroscopy. MP removal efficiency of AAT was found to be 93,7%. Despite this, approximately 522 210 MP is released into the aquatic environment every day due to high volumes of treated wastewater flow rates. The abundance of MPs in the sludge cake was calculated as 9,5±2,3 s/g, the sludge disposal amount of WWTP was 81,5 tons/day and the amount of MP accumulated in the sludge per day was calculated as 774 250 000 MP. Shape, size, color and type in wastewater and sludge samples; fragment-shaped, 1000 - 500 μm in size, black in color and PE and PP types were determined as the dominant ones.