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In this study, we compared the results of biomass and biocarbon content analysis of Solid Refuse Fuels using 14C method and selective dissolution method. Solid Refuse fuel Samples for biomass and biocarbon contents analysis were each collected from the silos and stack of the respective three facilities. Samples collected for 1, 10, 20, and 30 days for each method were analyzed. The analysis data were grouped into sample period, type and method and the optimum method for the detection of the biomass and biocarbon content was estimated. The biomass and biocarbon content showed a partially normal distribution. However, it does not satisfy equal variance. Therefore, we applied the parametric statistics Welch's ANOVA test and the nonparametric statistics Kruskal-Wallis test to compare the means of each sample group. The results of the Kruskal-Wallis test showed that sapmles collected over 20 days at Facility A had the same mean value. Therefore, when analyzing biocarbon content using the 14C method, conducting analyses by collecting exhaust gases for more than 20 days reduces errors in the results.

Korea’s Ministry of Environment has implemented the Framework Act on Resource Recirculation to activate waste resource recovery. However, industrial waste treatment facilities have some problems related to diversity of waste received for proper management of wastes. Waste incineration facilities are required to receive and process combustible waste and are forbidden to re-consign waste to other waste treatment facilities without any processing. In reality, a large amount of incombustibles is injected into the incinerator because it is impossible to completely separate the incombustible materials. Therefore, it is necessary to develop additional management criteria for optimal operation of the incineration facility. This study was conducted to improve institutional management of incineration facilities in Korea. Through a literature review and statistics study, incombustible waste management trends were investigated. The characteristics of waste entering incineration facilities were surveyed. Physical composition and proximate analysis of incoming waste were conducted, and properties of the incombustibles mixed in feedstocks to waste incineration facilities were examined. As a result of this study, incombustibles mainly consisting of the construction and demolition waste, such as soil, glass, and metals, should be separated from feed sent to incinerators. A mechanical screening technique that sorts particles of 30–40 mm in size can be used to separate the incombustibles. Also, management criteria could be proposed to sort and re-consign the incombustibles.

The Ministry of Environment, South Korea, is involved in efforts to reduce safety-related accidents that could occur during hazardous waste disposal and minimise the environmental impacts of waste disposal. To reach such goals, new factors have been added that contribute to the hazardous characteristics of hazardous waste. The Ministry is also expanding regulations on inorganic and organic components present in hazardous waste for these factors and continues to correct the classification system to establish standards for waste components. Metallic dust, for example, is mostly generated during the operation of melting furnaces or precipitators and dangerous materials contained in this dust may cause accidents, such as explosions or fires. South Korean accident cases have confirmed that waste containing hazardous materials, such as Mg, Al and Mg–Al alloys, can cause such events. Therefore, this study analysed 28 dust samples collected from the dust accumulated in precipitators in 28 metal manufacturing facilities in South Korea. Nine samples were flammable and four samples were reactive to water. Two samples also exhibited leaching toxicities. The results applied to relevant laws in South Korea showed that the proportion of waste containing hazardous characteristics increased from 7.14% in the previous management category to 39.29% in the extended category, an overall increase of 32.15 percentage points.

With an increasing use of plastic, considerable plastic waste is generated, threatening the environment and public health. In particular, changes in living patterns in urban areas have significantly impacted the rate at which plastic waste increases every year. Thus, governments in many developed countries have implemented numerous policies to reduce plastic waste generation. Among them is the concept of circular economy that aims to protect the environment from plastic pollution and promote growth and innovation in industry and human life through overall changes in designing, producing, using, and recycling plastic products. The Korean government has implemented the Resource Circulation Act (RCA), which includes the concept of circular economy and resource efficiency policy for overall waste management. Following the concept of RCA, the Plastic Waste Control Plan (PWCP) was established for the comprehensive management of plastic waste. Therefore, this study introduces the goals and strategies of PWCP, which has a circulation system of four stages of production, consumption, discharge, and recycling, as well as the major roadblocks in the stages impeding the achievement of the goals and strategies. This study also suggests countermeasures at the government level for solving the major problems in the four stages.

The study conducted basic component analyses including three component analyses, elementary analysis and heavy metal content and BMP test according to the mixing ratio for food waste leachate and wastewater treatment sludge(from brewery, dairy factory, bread factory, sewage sludge), and calculated biogas production speed using mathematical models. According to the elementary analysis of organic wastes, the C/N ratio, a major condition for anaerobic digestion, is 5.40–9.23, except for food waste leachate (FWL). Defined by Tchobanoglous’ mathematical biogas prediction model, methane gas and biogas productions increased, depending on the mixing rate of FWL. Furthermore, anaerobic digestion of both wastewater sludge and food waste leachate based on the correct mixing ratio, increases methane gas productions compared to digesting wastewater sludge alone. In other words, co-anaerobic digestion is more likely to realize biogasification than single anaerobic digestion. We mixed food waste leachate and wastewater treatment sludge by proportion of 1:9, 3:7, and 5:5, respectively. It turns out that they produced 118, 175, 223 CH4 mL/g VS with the dairy factory, 176, 233, 263 CH4mL/g VS with the brewery, 268, 300, 314 CH4 mL/g VS with the bread factory and 233, 298, 344 CH4-mL/g VS with the sewage sludge of methane gas. The result proposes that as the mixing rate of food waste leachate rises, the methane gas production increases as well. In the case of co-digestion of wastewater treatment sludge and food waste leachate based on the mixing ratio, more methane gas is produced compared to single digestion of wastewater treatment sludge. Modified Gompertz and exponential models describe the BMP test results that show how methane gas is produced from organic waste. According to the test, the higher the mixing rate of food waste leachate is, the higher the methane gas production is. The mixing ratio of food waste leachate which produces the largest volume of methane gas is 1:9 for the dairy and bread facilities and 3:7 for brewery and sewage sludge. Modified Gompertz and exponential models describe the test results very well. The correlation values (R 2) that show how close the results of model prediction and experiment are 0.920–0.996.

Management of solid recovered fuel (SRF) in South Korea is unique from most other countries in that it is based on a single standard. All SRFs are distributed at the same price irrespective of their performance, resulting in utilization problems and a low degree of acceptance among consumers. Moreover, the difficulty of temperature maintenance during transportation, excessive ash content, and the use of inappropriate microwave acid digestion methods pose challenges to SRF reliability. To address these issues, we compared the relevant management statuses in South Korea with those of the international community and reviewed the effects of the transportation temperature, ash content, and microwave acid digestion technique. The moisture, ash, sulfur, and chlorine contents as well as the lower heating values (LHVs) of all the samples from South Korea were found to be below the standard [international] thresholds, and they were barely influenced by the transportation temperature. In addition, 5 g samples were found to be more appropriate for ash content analysis than the 20 g samples used in South Korea, with the former producing smaller standard deviations. The optimal microwave acid digestion conditions were also determined to be a reaction time with nitric acid of >10 min, temperature of 180 °C, and microwave power of 600 W. The results of this study highlight the need for revising the SRF test methods used in South Korea, to boost the market and enhance quality reliability.