Recently, by the whole world paradigm shift to “Low Carbon Green Growth", it is required to renovate National Transportation and Logistics System. Transportation accounts for 21% of the total energy consumption and 20% of the total CO2 emission, and also places its main reliance on fossil fuels. From green point of view, electric railway system is superior to the other transportation alternatives, but also required to develop the innovative technologies for high efficiency and low energy consumption. In this paper, the concept of railway green operation system by regenerative synchronized driving is presented, including the numerical example and the estimated effect.

Domestic automotive shredder residue (ASR) recycling facilities must comply with 60% of the energy recovery criteria calculated by the waste control act, based on resource circulation of electrical and electronic equipment and vehicles. The method of calculating energy recovery criteria was newly enacted on November 6, 2017, and it has been judged that it is necessary to consider applicability. In this study, the energy recovery efficiency of 7 units was calculated by past and present calculation methods. Furthermore, this study attempts to find applicability and a method of increasing the energy recovery efficiency by taking advantage of available potentials. An analysis of the calculation results showed that the average values calculated by past methods, present methods, and the method that includes available potentials are 76.35%, 70.68%, and 78.24%, respectively. Therefore, the new calculation method for energy recovery efficiency is also applicable to domestic automotive shredder residue recycling facilities.

In this study, we analyzed all of the waste streams associated with household waste to provide a basis for incorporating the individual characteristics of municipalities in setting targets for waste-to-resource circulation. Toward this end, we examined how household waste is treated based on the disposal method (mixed waste disposed of in standard volumerate garbage bags, separation recyclable waste, and food waste) and the amount of residuals generated at their respective treatment facilities. The actual recycling rate or actual waste-to-energy conversion rate was calculated as the ratio of the actual amount of waste that is recycled or converted to energy against the amount of waste intake at waste treatment facilities. The conversion factor of actual recycling rates at 17 municipalities showed an average of 63.9% for public material recovery facilities (MRFs) with those for individual municipalities ranging from 50.4% to 93.2%, and an average of 93.8% for private and public food waste treatment facilities with slightly higher rates found for public facilities (70.4 ~ 100%) than private facilities (63.3 ~ 100%). The actual waste-to-energy conversion factor was 59.3% on average for combustible waste-to-energy facilities (17.2 ~ 72.3%) and 92.0% on average for biological waste-to-energy facilities (77.1 ~ 99.5%). To achieve the national target for the actual recycling rate, additional strategies for recycling or converting the residuals generated at recycling or combustible waste-to-energy facilities into resources are needed. The actual recycling and waste-to-energy conversion rates provided in this study based on a full examination of household waste streams hold valuable insights for incorporating the individual situations of municipalities in setting their targets for wasteto- resource circulation indicators and creating new strategies for improving the actual recycling rate.

Aluminum can is one of the common and economically valuable recycling items in municipal waste streams. In this study, the reduction rate of the greenhouse gas emission and energy savings were estimated when aluminum cans are recycled by using material flow analysis, US EPA WARM method, and EU Prognos method. Based on the results, approximately 16,630 ton of aluminum in 2010 was recovered as ingot, while 10,873 ton of aluminum can to can recycling occurred in the same year. The reduction rate of aluminum recycling was estimated to be 240,986 tCO2eq/yr by US EPA WARM method, while about 305,283 tCO2eq/yr was found by the recycling using EU Prognos method. The difference resulted partly from the different system boundary and the loss rate during aluminum recycling process. The results of the energy savings and greenhouse gas reduction rate would be valuable for waste management policy makers to estimate the potential reduction rate of greenhouse gas by aluminum can recycling and accelerate recycling infrastructure of waste streams. This study also implies that the applications and results of both methods to estimate greenhouse gas reduction rates by aluminum can recycling should be carefully reviewed and acknowledged before the use of the method due to the different assumptions and results that are anticipated.