Recently, the construction of tall buildings utilized by high strength-concrete in the whole world is tending to be on the rise. The application of high-rise structural system in buildings results in the excellent cut-down effect in construction materials due to section reduction. Therefore, in order to investigate the CO2 and resource reduction effect for the high-rise structural system, comparisons of GWP and ADP in embodied energy of structural materlais between 4 type of high-rise structural system have been performed. As a result, GWP emission increased in the order of steel structure outrigger system, RC shear wall system, and RC outrigger system. On the other hand, ADP emissions increased in the order of RC shear wall system, RC outrigger system, and steel structure outrigger system.
Industrial symbiosis (IS) activities within an industrial complex can enhance environmental and economic efficiencies. This study proposed a simplified life cycle assessment (LCA) methodology as an effective tool with which to evaluate the reduction of environmental impact of IS activities. In this method, the variation of resources and energy consumptions before and after IS activities are proposed to simply evaluate its lifecycle environmental impacts. The simplified LCA was applied to an IS case between an industrial waste incineration plant and a steam production plant of a paper mill firm in the metropolitan city Ulsan. The system boundary and inventory were set for this IS, and an environmental impact assessment was carried out by standard and proposed LCA methods. The results showed that the environmental impacts after IS decreased in all impact categories with regard to the consumption reduction of boiler fuel used at the paper mill. Furthermore, the performance of environmental improvement activities such as IS can be simply evaluated by only considering the input and output changes in the environmental improvement activities. In this IS case study, the environmental impact was decreased by 11.7% (weighted impact base). This was due to the utilization of waste heat generated from an incineration plant in the process of the paper mill firm.
This research evaluated the environmental impact of waste film used in the farming industry which is subject to voluntary agreement by Waste Charge System using Life Cycle Assessment (LCA). When analyzing the environmental scores applying weighted values, production of raw materials, production of goods and disposal had nearly 73%, 15% and 11% of contribution to the environmental impact and also, amongst impact categories, resource depletion and global warming had 63% and 32% of contribution respectively. For resource depletion which had the highest contribution, production of raw materials, production of goods and disposal occupied around 86%, 9% and 4% of it, and the impact category of resource depletion that belongs to production of raw materials, accounted for about 54% of the whole environmental score. Here, over 95% of it was caused by crude oil. When investigating the contribution of each phase to global warming that is the key issue of low carbon green growth, production of raw materials, production of goods and disposal had respectively, 45%, 28% and 27% of contribution. As the result, production of goods and disposal had higher contributions than resource depletion. The entire contribution of production of goods and disposal to global warming was about 17%, and it is predicted that it would bring a huge impact, considering the possibility of establishing improvement plans. In the production of goods, electricity consumed was the main cause of global warming, and electricity used in the recycling process and incineration occupied approximately 52% and 42% of the disposal stage. In conclusion, we should pay attention to energy used in the production of goods and recycling for improving an environmental competitiveness of goods, and reduction of energy would be able to satisfy economic feasibility and environmental efficiency of the whole process of agricultural PE film.
This research evaluated the environmental impact of polyethylene water supply pipe which is a target of voluntary agreement by Waste Charge System using Life Cycle Assessment (LCA). When analyzing the contribution of each impact category to the environmental score, resource depletion had the highest contribution at 57% and it was followed by global warming with 35% of contribution. Amongst the entire process and stage, production of raw materials, production of goods and disposal had about 60%, 18% and 18% of contribution, respectively. For resource depletion which was found to have the highest contribution, production of raw materials, production of goods and disposal accounted for nearly 77%, 11% and 7% of it, and the impact category of resource depletion which belongs to production of raw materials accounted for nearly 44% of the whole environmental score. Here, it was found that 88% of it resulted from crude oil. When analyzing the contribution of each stage to global warming that is the key issue of low carbon green growth, then, production of raw materials, production of goods and disposal showed around 38%, 29% and 28% of contribution, respectively. As the result, production of goods and disposal had higher contributions than resource depletion. Electricity used for production of goods is the major cause of global warming, and electricity used in the recycling process and incineration occupied about 65% and 36% of the disposal stage. In conclusion, we need to seek for plans to reduce the use of electricity through optimization of energy use during the production of goods and disposal, in order to establish an environmental and economical competitiveness of PE-related enterprises that are operated on a small scale.
In this study, life cycle assesment (LCA) was conducted based on a functional unit of 1 ton of food waste recycling from collection and transportation to treatment processes such as feed production, composting, other recycling and incineration for 45 public food waste recycling plants. The Korean life cycle inventory (LCI) data were used for the main input material and energy. For the other input data, which could not be provided by the Korean LCI database, data of other countries were used from the database by Ecoinvent, and the strength of food wastewater for LCI DB was divided low and high concentration. In case of low strength of food wastewater, environmental impacts were suggested incineration, composting and feed production in the order, where collection and transportation were identified as the major influencing factors by contribution analysis and sensitive analysis. Contrary, in case of high strength of food wastewater, environmental impacts were suggested composting, feed production and incineration in the order, where treatment of food wastewater was identified as the major influencing factor. Therefore, discharge volume as well as concentration of food wastewater was found to be important parameter of the LCA.