National statistics of solid waste indicate that, although the amount of combustible wastes from household sectors is decreasing, the amount of waste that is buried in landfills increases each year. And the increasing rate of combustible wastes from industrial sectors is higher than the decreasing rate of combustible wastes from household sectors. Combustible waste, once screened, can be used as a potential energy resource contributing to resource circulation. Therefore, the objective of this study was to predict the amount of waste materials to be recovered and recycled by landfill mining and reclamation (LFMR), based on material flow analysis for four existing landfills. In this study, the landfills analyzed by material flow analysis were classified into types 1 to 4 by considering the status of the landfill and incineration situation. In order to perform material flow analysis, volume increase rate and bulk density were applied to the methodology employed in previous studies. In addition, material flow analysis software ‘STAN 2.0’ was used for the analysis. As a result of analyzing the average value of four landfills, the landfilled waste was classified as 93.9 m3 (73.7%) of combustible waste, 9.2 m3 (7.3%) of incombustible waste, and 24.3 m3 (19.1%) of soil matter. So, 73.7% can be incinerated or recovered by energy, 7.3% can be recycled as materials and reclaimed, and 19.1% can be recycled as landfill cover materials based on weight. The results of the material flow analysis carried out in this study are expected to be used to predict the amount of waste materials landfilled to be recovered by the material flow analysis during landfill mining processes.

In order to promote the resource circulation and upcycling of waste refrigerators, it is necessary to analyze the material flow of recovered valuable resources and low-value residues after they are discharged. This study divided the flow of waste refrigerators into the five steps of discharge, collection, pretreatment, resource recovery, and sale/export/disposal and conducted material flow analysis (MFA) in each step. Waste refrigerators are treated via official (formal sectors, 65.6% of total amount) and unofficial (informal sectors, 34.4% of total amount) channels. Officially, waste refrigerators are collected through free collection by national and local governments, recovery by product producers and distributors, and waste collection·transportation·recycling companies and are recycled at public and private recycling centers. Unofficially, waste refrigerators are collected through junk shops and individual collectors. Waste refrigerators recycled in the formal sectors undergo pretreatment processes such as the disassembly, shredding, and separation and recovery of resources such as scrap irons, plastics, PCB (printed circuit board), cables, glasses, waste refrigerants, urethane, etc. Waste refrigerators recycled in informal sector treated through disassembly of the exterior, the shredding process by the excavators in illegal facilities and recovered waste refrigerants, plastics, glasses, scrap irons, copper, nickel silver, PCB, urethane, etc. MFA results show that in 2015, the amount of waste refrigerators collected from formal sectors reached 121,642 ton/year, the amount of recycling was 107,684 ton/year, and the amount of residues was 13,955 ton/year respectively. Thus, actual recycling rate per a waste refrigerator was estimated 88.15% in 2015. To promote the resource circulation and upcycling of waste refrigerators, it is necessary to find a way to improve the recycling of urethane, which accounts for 10.8% of the total weight of a refrigerator.

The flow of products containing valuable metal resources after discharging to waste means that it is necessary to form a plan to improve resource circulation to enhance the circulation of metal resources. In this study, waste resource circulation flow analysis of products containing cobalt and palladium after disposal was performed by classifying five stages: (1) discharge/import, (2) collection/discarding, (3) pretreatment, (4) resource recovery, and (5) product production/export. The mobile phone was one of products which were the most generating cobalt. Discharged cobalt was kept for processing or was produced as pure cobalt, cobalt oxide, or cobalt sulfate, and was used as a raw material for locks, speakers, AlNiCo magnets, tire, batteries, etc. The total amount of cobalt in the waste products was 994 tons and the recycling rate was 53.7%, indicating that 543 ton of cobalt was recycled. Palladium was discharged from waste electrical and electronic products, precious metals, petrochemical catalysts, vehicles catalysts at the end of their life, and medical equipment (dental). The palladium recovered by pre-treatment and resource recovery was recycled as a metal resource or exported. The amount of palladium recycled was 2.412 tons, of which a total of 2.512 or 96% tons is estimated to be recycled. Future research may be necessary to suggest institutional improvements, including the waste resource classification and market expansion for the recycling in the five steps based on the results of this study.

Neodymium(Dysprosium)-permanent magnets (Nd(Dy)-Fe-B Magnets) have necessity and potential to be recycled given their high criticality and important roles in various high-tech fields as well as the characteristics of being selectively disengaged from the assemblies in which they are used. This study focused on secondary material flow (downstream) of Nd(Dy)-Fe-B Magnets in South Korea. The quantitative information includes the primary data of each category (Emission - Collection - Disengagement - Resource Recovery - Remanufacturing) with domestic recycling situations of the magnets, which can contribute to more effective policy-making. As a result of the material flow analysis, this study provides the primary data of Nd and Dy at each stage and inhibiting factors (bottleneck) of Nd-Fe-B Magnets recycling and suggests the method for improvement of recycling of rare earth magnet.

The materials flow of nickel was analyzed into up-stream and down-stream based on the literature survey. Dischargeand recycling stages in the down-stream were analyzed through the field survey. The waste nickel resources circulationflow were analyzed into 4 stages such as discharge·import, collection·disuse, resource recovery and product production·export, which are divided into nickel scrap and stainless steel scrap. The nickel scrap of 1,500ton was collected andrecycled and exported, which are from battery, catalyst and etc. The stainless steel scrap of 55,200ton are recycled fromdomestic and imported sources, which are 28,800ton and 26,400ton, respectively. The resource circulation rate of 45.3%is obtained from the above flow and the various plans are suggested each stage to increase resource circulation rate. Atdischarge·import stage, it is suggested this kind of waste may be classified as resources if the classification of waste isdone in detail and suitably. Also, it is suggested to apply quota tariff to this kind of waste. At collection·disuse stage, theplan of stabilizing supply and demand is suggested through the improvement of bidding system. At resource recovery stage,the fostering plan for specialized crushing companies and the win-win plan between conglomerate and medium-smallcompanies are suggested. At product production·export stage, it is suggested the integrated approval for licensing to registeras waste-treating facilities instead of exempting registration under the present condition to activate recycling industries.