Plastic capture methods in the water bodies, a review of world experience

Abstract

Over the past twenty years, the plastic pollution problem in the water bodies has reached an alarming scale. The easy-to-use, light, waterproof material has the significant drawback, it is the very long decomposition period, which has led to the 368 million tons of plastic accumulation over the past 70 years, and the accumulation continues. Plastic environmental pollution is the urgent problem for the water bodies in Ukraine too. The source of plastic entering water bodies is primarily temporary waste landfills from which plastic is washed into rivers and lakes during rains, by wind and by flood. The rivers carry plastic throughout the river floodplain, polluting riverbeds and banks during the flood. In the work, the analysis of the world experience in the area of the plastic capture devices and the possibility to use these devices for the mountain rivers conditions in Ukraine was assessed. The peculiarities of the hydrological regime of the mountain rivers are the transportation of plastic during floods, significant water levels fluctuations, the danger for people being in the riverbed during the flood, high water speeds up to the 5 m/s, the large amount of litter, which in consists of the plastic, tree trunks, branches and other large debris. It was assessed the booms, trash traps and trash racks for catching litter in water outlets and temporary streams. Plastic collecting facilities such as floating boats, catamarans, and robots were not assessed, because their use during the flood is dangerous, and the small water depths in the rivers do not allow to use them effectively during the low water period. Devices for plastic capture for the mountain rivers should be autonomous, strong, have the big litter capacity, be ecological friendly, able to work with rapid water level change and under high water speed. Analysis of the existing devices shows that these requirements will be met by expensive segment. At the same time, it is known that the plastic capture in the water bodies costs in 10 times higher than the cost of collecting and sorting plastic in the populated areas. So, to solve the problem of plastic pollution in the water bodies by the expensive devices is not right way. First of all, in order to reduce plastic pollution in water bodies, it is necessary to create conditions to prevent plastic to get into the rivers, namely: voluntary limitation of the plastic usage, manufacture responsibility for the use of recyclable plastic, active informing society about the plastic harm to the environment and the necessity to collect and sort it.