간행물
한국폐기물자원순환학회지 KCI 등재 Journal of Korea Society of Waste Management
- 발행기관 한국폐기물자원순환학회
- 자료유형 학술지
- 간기 연8회
- ISSN 2093-2332 (Print)2287-5638 (Online)
- 수록기간 1984 ~ 2018
- 주제분류 공학 > 환경공학 공학 분류의 다른 간행물
- 십진분류KDC 539DDC 628
권호리스트/논문검색
제35권 제2호 (2018년 3월) 11건
1.
2018.03
서비스 종료(열람 제한)
Recently, the concept of “sustainable resource circulation society” has become a global issue and a key part of waste management policy. For resource circulation, Korea has established the primary foundation via the enactment of the “Framework act on resource circulation.” Waste energy recovery is attracting considerable attention because of such policy changes, and efforts are being made to maximize the use of heat at incineration facilities. Moreover, to ensure the objectivity and validity of the estimation method’s results, the ministry of environment has recently revised the guidelines for the energy recovery rate estimation method and lower heating value (LHV) of waste at incineration facilities. In the revised guidelines, for estimating the LHV of waste, a formal formula is presented at general incineration facilities for municipal solid waste (MSW). However, generally, the LHV-formula at incineration facilities is difficult to apply to pyrolysis-melting facilities because it does not reflect characteristics of the pyrolysis-melting treatment method. Thus, in this study, the actual condition of pyrolysis-melting facilities was investigated, and the LHV-formula for pyrolysis-melting facilities was derived using the derivation method of the EU’s NCV-formula.
2.
2018.03
서비스 종료(열람 제한)
The amount of sewage sludge that is emitted is gradually increasing every year. However, since 2012, because of the London Protocol, the oceanic dumping of sewage sludge has been prohibited. Therefore, for recycling organic waste, either the ground disposal method has to be used or technological solutions that develop energy from such waste have to be identified. Heat is generated when the sewage sludge has decomposed by aerobic microbes. In this study, to dehydrate sewage sludge, heat was applied and the drying efficiency was evaluated according to the air flow rate (AFR) and the proportional mixing of the returned sludge. For the experiments, returned sludge that was dried to 40% moisture content was used; consequently, the highest temperature was obtained when the moisture content was 30% and, for maintaining aerobic conditions, the optimal AFR was 200 ml/min·kg. During biodrying for 14 days, the highest temperature of reactor was 46℃, which was maintained at higher than 40℃ for 5-7 days; moreover, 18.8% of moisture was eliminated. These results show that using biodrying for treating sewage sludge has economic potential compared to hot-air drying; moreover, with additional treatment, biodrying can be one of the methods for producing Bio Solid Refuse Fuel (Bio-SRF).
3.
2018.03
서비스 종료(열람 제한)
Using a mixture of sewage sludge and woody waste, optimal conditions for the bio-briquette process of carbonization residue were evaluated by compressive strength and bulk density. For the bio-briquette process, the optimal conditions were determined to be a molding temperature of 110oC and a moisture content of 10%. As the lignin in the carbonization residue can be used as a natural binder because of its plasticizing property, the bio-briquette process uses this property. To increase the compressive strength to >3.50 MPa, binders such as polyvinyl alcohol (PVA), guar gum, and starch were mixed in the carbonization residue. At 3 wt.% of PVA, 3 wt.% of guar gum, and 5 wt.% of starch, the conditions of binder usage were evaluated. To examine the cost in the bio-briquette production with the addition of the binder, the proportion of binder cost for the bio-briquette production were evaluated at 9.2% for PVA, 8.6% for guar gum, and 3.3% for starch, and starch was determined to be the best binder for the bio-briquette process.
4.
2018.03
서비스 종료(열람 제한)
Since the 1990s, waste policies of the South Korean government have focused on resource recycling societies that reduce the amount of waste landfill and increase the amount of waste recycling. In South Korea, the implementation of various environmental policies and efforts has led to the highest recycling rate in the world; however, after 2011, the recycling rate of household waste has been stagnant. Therefore, to convert such waste disposal problems into a resource recycling socioeconomic regime conforming to the national policy, establishing a tool to evaluate the appropriate management policy of household waste is necessary. In this study, a waste management evaluation index was developed and applied to identify and evaluate trends in the waste disposal methods. For the evaluation index, we considered two points of evaluation, i.e., “waste recycling increases and waste landfill decreases” and “the current waste recycling rate is taken into consideration.”. The data of waste disposal of 2007, 2012 and 2015 in 16 municipalities was used. The results shows that the highest absolute index was (+)28 in Chungbuk, whereas the lowest was analyzed as (-)10 in Daegu. Moreover, the cities with high recycling rates and low landfill rates were Seoul and Busan, while Jeonnam had the low recycling rate and the high landfill rate. Furthermore, Chungnam and Chungbuk were very likely to develop further, whereas Daegu and Incheon had a very low possibility of development. This waste management evaluation index and method can be one important tool and approach and can support more sustainable and resource recycling socioeconomic.
5.
2018.03
서비스 종료(열람 제한)
The fast pyrolysis of biomass (larch) in a circulating fluidized bed pyrolyzer was performed and the physico-chemical characteristics of biocrude-oil was investigated. Standard sand was used for fluidizing material and various reaction temperatures from 400℃ to 550℃ was applied. Wood (larch) sample was examined thorough proximate analysis and thermogravimetric analysis (TGA). From the results of the sample test, thermal decomposition characteristics of wood (larch) was investigated. Various analyses were carried out to determine the physicochemical properties of biocrude-oil such as Higher heating value (HHV), water content, viscosity, ash content and microscopic anaysis. The maximum biocrude-oil yield was 49.9wt.% at 550℃. At this temperature, HHV and water content were 4562.0 kcal/kg and 13.8wt.%, respectively. From the study results, wood (larch) has potential as an alternative energy source.
6.
2018.03
서비스 종료(열람 제한)
Landfill gases (LFGs), which consists of sulfur compounds, odorous substances such as ammonia and amines, and volatile organic compounds (VOCs), is generated during the natural process of bacterial decomposition of organic material contained in municipal solid waste (MSW) landfills. The VOCs in the LFGs cannot be only decomposed easily into the soil after landfilling but they also can cause serious problems for the surrounding atmosphere, soil, and groundwater because of their toxicity. Moreover, VOCs have been identified as precursors of photochemical smog and they are toxic and carcinogenic chemicals. Furthermore, VOCs comprise a low rate of the emissions, but they can cause cancer. Therefore, it is important to evaluate the hazard causing by VOCs in LFGs. This study is aim to identify chemicals in LFGs and the hazardous evaluation by mixing between chemicals in LFGs. The selected landfill site in the study is located in Daejeon. Waste generation data were obtained from the Ministry of Environment (MOE) of South Korea. To evaluate the amount of the selected VOCs (47) among the primary disintegration models, LFGs generation model in LandGEM program was used. For the gas mixing reaction, a program called CRW 4.0 was introduced by the NOAA in the United States was used. As a result, the cumulative capacity of landfills in 2015 was estimated at 7,650,682 tons. Therefore, the total LFGs generation in 2015 was 7.717 × 107m³. Also the LFGs showed almost all the hazardous reactions with NOx and O3 in the atmosphere. As VOCs in LFGs mixed air emissions, we confirmed that toxic potential gases such as phosgene, hydrogen halides, halogenated organics, chlorinated amines and acidic fumes are generated.
7.
2018.03
서비스 종료(열람 제한)
In accordance with the 1996 London Protocol, the marine dumping of wastewater generated from food was totally banned from 2013. Therefore, establishing a food wastewater bio-gasification facility for stable and continuous food wastewater treatment is necessary. The biogas produced from the wastewater can be used as fuel for electricity generation or for heating in power plants and can be sold as gas in cities as well as fuel for vehicles after undergoing a refining process. Thus, the South Korean government is trying to expand the bio-gasification facility of wastewater generated from food. In this study, we try to obtain information about the public value of such an expansion. For this purpose, the household willingness to pay (WTP) for the expansion is determined by applying the contingent valuation (CV) approach. A total of 1,000 South Korean households were involved in the CV survey, which had questions with dichotomous choices. The mean yearly public value WTP for expansion is estimated at 2,564 KRW per household. If this WTP is extrapolated from the sample to the nation’s population, the expansion in the national value is worth 50.1 billion KRW per year. These results indicate that the expansion of food wastewater bio-gasification facility is supported by Korean households.
8.
2018.03
서비스 종료(열람 제한)
In this study, to evaluate the transboundary movement of magnetite waste, the treatment causing possible oxidation and reduction to the highly toxic Cr (VI), as well as other chromium ions must be considered. In this study, we tried to remove chromium using magnetite. The efficiency of chromium removal using magnetite, mixing time, mixing speed, and temperature was evaluated through a jar test. In case of magnetite, the total chromium and hexavalent chromium concentration were rapidly decreased to 0.7 g and 0.35 g, respectively. For mixing speed, the removal efficiency of total chromium was rapidly increased to 150 rpm, but that of hexavalent chromium was almost unchanged. For reaction time, the chromium concentration was almost identical. At 70℃, the removal efficiency of total and hexavalent chromium was 97.2% and 98.8%, respectively; therefore, application of magnetite to actual industrial sites where high-temperature industrial wastewater is generated can be considered.
9.
2018.03
서비스 종료(열람 제한)
In the past, the role of incineration facilities was mainly to reduce waste and stabilize disposed material. However, as a key aspect of waste management policy, the concept of “waste Minimization and sustainable resource circulation society” has become an issue, and the effective use of waste has been emphasized. As a result, to promote the recycling of wastes from January 1, 2018, the Framework Act on Resource Circulation has been implemented. In this study, estimation factors that can affect the increase of energy recovery are selected by reviewing the estimation method of industrial waste incineration facilities having a separate boiler; moreover, the effect of calculation factors on energy recovery was quantitatively evaluated. According to this study, when the heat loss, condensate temperature, and power consumption decrease by 10%, the energy recovery of the target facilities increase by 0.4% (0.22 ~ 0.63%), 1.09% (0.57 ~ 1.32%), and 1.16% (0.52 ~ 2.13%) on an average.
10.
2018.03
서비스 종료(열람 제한)
A great variety of plastics are used in IT products, which differ not only by plastic type but also by color and presence of additives such as brominated flame retardants (BFRs). In this study, to identify the plastics containing BFRs and heavy metals (i.e., Pb, Hg, Cd, Cr6+), laser-induced breakdown spectroscopy (LIBS) was used. Polypropylene (PP)-type black plastic samples that were obtained from three different types of used electric cookers were analyzed. The spectrum peaks observed in the LIBS system confirmed the presence of BFRs and heavy metals. The number of Br peaks were identified and the data were compared with the previous atomic spectra database. In the near future, the recycling of plastics from e-waste may become more important not only to reduce the amount of waste requiring treatment but also to eliminate the plastics containing hazardous components and compounds.
11.
2018.03
서비스 종료(열람 제한)
Based on a survey of Korean waste-to-energy (WTE) firms, this article analyzes the R&D effectiveness of the WTE industry, which accounts for the largest proportion of new and renewable energy power generation in Korea, using multiple and logistic regression. A company’s R&D can be considered effective if its R&D inputs (e.g., R&D expenditure/sales, R&D manpower/employees, education/training, and reward systems) or R&D outputs (e.g., patent applications and approvals, the introduction of new products and services, and the redesign of products and processes) contribute to an increase in R&D outcomes (e.g., decrease in production costs, the creation of employment, and market entry). It was found that market entry is not affected by R&D inputs but is positively influenced by R&D outputs, indicating that Korean WTE firms have focused on market entry via the technology transfer of new products and services and/or the redesign of products and processes. In the WTE industry, the creation of employment does not have a statistically significant relationship with R&D expenditure/sales, R&D manpower/employees, or the redesign of products, but it does exhibit a positive relationship with education/training, reward systems, patent applications and approvals, and the introduction of new products and services. Finally, the decrease in production costs is not influenced by R&D expenditure/sales, R&D manpower/employees, reward systems, or patent applications and approvals, but is positively affected by education/training, the introduction of new products and services, and the redesign of products and processes. A policy implication of these results is that market entry show the virtual cycle on expanding R&D expenditure/sales and/or R&D manpower/employees.
