Otomotiv endüstrisinde kataforez prosesinin önemli çevresel etkileri

Due to the rapid growth of the industrial population, increasing population, changing climate conditions and world conditions, the environmental effects of industrial growth are increasing day by day. For this reason, developed countries are trying to reduce water consumption, chemical and energy consumption, and increase the effectiveness of sustainability. In recent years, the cataphoresis system is widely used in the automotive industry. In this context, the main purpose of this study is to demonstrate the environmental impact of the cataphoresis process used in the automotive industry using the product life cycle assessment approach. This study evaluates the widely used cataphoresis process of automotive industry, with an annual production of 6109 vehicles (trucks, busses), in terms of its water, chemical and energy consumption and investigates the sustainability of the mentioned process by the life cycle assessment approach. First of all, the water management system of an automotive factory was examined and the recoverability ratios were determined. Later, the cataphoresis system was investigated by the life cycle of environmental effects. Data were collected for one year after the system limits and functional unit were defined. The materials used and the electricity consumption are measured for cataphoresis coated metal surface of 1m2 vehicle. System boundaries consist of cataphoresis pretreatment and electrocracking processes. Water inputs and outputs are the main processes that are examined in terms of the continuous and continuous flows, energy inputs, chemical inputs, and the transport processes of chemicals. In addition to these, the processes of wastewater treatment and dehydration and removal of phosphate mud are also included in the processes. Extensive amount of water input together with various chemicals are required by automotive industry. The cataphoresis process is composed of two main sub-processes: pretreatment and electrodeposion (ED) coating. The retreatment or surface preparation process consists of a series of operations, which includes the hot water rinsing, degreasing, rinsing, surface activation and phosphate coating followed by several rinsing steps. After these operations, electrodeposition coating takes place. As a result, of the cataphoresis process, a metal surface resistant to corrosion and ready to further surface applications is obtained. Recycling and reuse of wastewater in this process is of great importance for sustainability studies as substantial amounts of water is consumed and wastewater is generated out of it. On the other hand, there is limited information in the literature on the reuse of wastewaters produced from cataphoresis rinse pools. The wastewater originating from the cataphoresis process contains heavy metal ions. In order to remove heavy metal ions from these effluents various treatment methods ie. chemical precipitation, adsorption, oxidation-reduction, electrochemical treatment, membrane technologies etc. can be used. The economic and technical limitations resulting from applying the mentioned methods trigger research activities to focus on promising emerging technologies. In this context the objective of this study is to evaluate the widely used cataphoresis process of automotive industry in terms of its water consumption and pollution loads, and to investigate the reclamation and reuse potential of segregated effluents arising from this process. The cataphoresis process of automotive sector is a water intensive industry. 0.68 m3 water is required for the cataphoresis operations per vehicle in the investigated facility. The results indicate that 43 % of the continuous effluents arising from cataphoresis process is reusable in nature. The amount of reusable wastewater streams can also be elevated by adding discharges from cooling system and boiler to the mentioned segregated wastewaters. By doing so 20 % of the whole wastewaters can be designated as reusable effluents after being subjected to an appropriate treatment. Besides, evaluation of cataphoresis process of automotive industry in terms of its water, chemical and energy consumption and investigate the sustainability of the mentioned process by the life cycle assessment approach is researched through this study. All data that have been used in the study was taken from the actual production. The inventory data was analyzed by GaBi 7.3 software. Data was collected based on the inputs and outputs for each process in the system. The inputs data include energy (electricity) and materials (chemicals, water, and others with various qualities). The outputs include the amounts of wastewater, co-products and wastes. The impacts categories are evaluated by GaBi software in terms of climate change (CC), acidification potential (AP), particulate matter and respiratory inorganics (PM), photochemical ozone formation (POF), ecotoxicity freshwater potential (EP), eutrophication (terrestrial, freshwater and marine), human toxicity potential (HTP), ozone depletion potential (ODP), and resource depletion (water). It was calculated the environmental impacts of a cataphoresis process of automotive industry via LCA approach. The environmental impacts of the investigated facility are in accordance with the literature values. The highest shares to the environmental impacts come form ED and UF water rinse tanks and the main contributors for this can be enlisted as energy usage. The total energy consumption in cataphoresis process of the investigated factory is approximately 12.5 kWh/m2. This energy consumption value is significantly higher than the literature. However, if the plant under study uses the full production capacity, it corresponds to the literature values of these consumption values. Literature studies are generally about production of passenger cars, while in our work we produce trucks and buses that enter commercial vehicle groups. The type of product produced can be said to be one of the factors that cause the difference because it does not affect the product production capacity. In this study, also effects of transportation is investigated in two parts: chemicals transportation and sludge transportation to cement factory. It has been found that the transport of chemicals, quantity, distance and transport route is effective, but the transport of chemicals is less than 1.60% of the total effect. The results shows that almost all environmental impact categories of cataphoresis processes are affected due to energy consumption. Therefore, four different scenarios are applied in this study to show the effect of renewable energy (wind turbine and photovoltaic), electricity from hard coal and grid mix electricity instead of grid mix of Turkey electricity on environmental impacts. The results show if wind energy is consumed as electricity source all of the impact categories decrease more than solar panels, grid mix and hard coal electricity. Whereas the hard coal power consumption increases most impact categories.