간행물

한국폐기물자원순환학회지 KCI 등재 Journal of Korea Society of Waste Management

권호리스트/논문검색
이 간행물 논문 검색

권호

제30권 제4호 (2013년 6월) 12

Original Paper

1.
2013.06 서비스 종료(열람 제한)
Infectious diseases in domestic animals of carcase were increasing every year. According to the monthly report for infectious disease from Ministry for Food, Agriculture, Forestry and Fisheries, 11,954 heads of cattle, 518,178 heads of pig, 232,850,244 heads of bird were reported in 2011. Infectious diseases of carcase almost spread on a national scale. Dead or emergency preventive carcase are completely treated on bury. Since the treatment of carcase on bury are generating soil, underground water and source water pollution, introduction of new preventive system should be considered. In this study, literature survey and case studies to prevent the spreading of virus for infectious disease and second environmental pollution were investigated. The actual experiments using the existing incineration facilities were also performed to ensure the possibilities of safe treatment of carcase. On the other hand, the moving-type incineration are also being developed and its operation manual will be prepared. Among the investigated incinerators, stoker type incinerator was not suitable for the treatment of carcase, however, other incinerators such as fluidized-bed type incinerator, rotary kiln type incinerator ware shown to be suitable. But even for the stoker type incinerator, if the pre-treatment facilities( grinding, crushing) are installed, it will also be a suitable method. The analytical results for air pollutants(including dioxin) emitted from the final exit were all satisfied to the air pollution emission standards.
2.
2013.06 서비스 종료(열람 제한)
This study aimed to investigate the optimal enzymatic hydrolysis conditions of alginic acid using Viscozyme® L, Celluclast® 1.5L, Saczyme®, Novozym®, Fungamyl® 800L, Driselase® Basidiomycetes sp., and Alginate Lyase, for production of reducing sugar. Response surface methodology (RSM) based on central composite rotatable design was used to study effects of the independent variables such as enzyme (1-9% v/w), reaction time (10-30 h), pH (3-7) and reaction temperature (30-70oC) on the production of reducing sugar from alginic acid. The coefficients of determination (R2) of Y1, Y2, Y3, Y4, Y5, Y6, and Y7 for the dependent variable regression equation were analyzed as 0.947 0.968, 0.840, 0.926, 0.923, 0.892 and 0.825. And the p-value of Y1, Y2, Y3, Y4, Y5, Y6, and Y7 within 1% (p < 0.01) was very significant. The optimal conditions were 1.0% of the quantity of the enzyme, 10.0 hours of the response time, pH 3 and 70.0oC of the reaction temperature, where the production rate was 483.1 mg/g-alginic acid, the highest of all the enzymes used.
3.
2013.06 서비스 종료(열람 제한)
Enzymatic biodiesel using lipase Novozyme-435 instead of using chemical catalyst was studied in this paper for cost reduction, increase of production efficiency and environment friendly product in this paper. In this paper the standard of biodiesel quality was met by using enzyme. The optimal reaction condition of methanol/waste oil molar ratio was 3, which 1 mol of methanol was injected at initial reaction. Then, each of 1 mol of methanol was injected at 4 hours of interval. Other reaction condition was like as follows : Reaction temperature, reaction time, agitation speed and amount of lipase were 55oC, 24 hours, 400 rpm, and 6wt%, respectively.
4.
2013.06 서비스 종료(열람 제한)
This research investigated the feasibility of rice husk as a biosorbent for the removal of heavy metals from aqueous solutions. The carboxyl groups were chemically bound to the surface of the rice husk by graft polymerization of acrylic acid using potassium peroxydisulphate as a redox initiator. The Pb sorption capacity and FT-IR spectra confirmed the presence of carboxyl groups on the structural units of the acrylic acid-grafted rice husk (RH-g-AA). The sorption selectivity of the RH-g-AA for cations under competition with each other was high in the following order: Pb > Cu > Cd ≥ Fe > Mn > Zn > Ni > Mg > K > Cr > Ca. Sorption equilibrium of Pb on RH-g-AA was better described by the Fruendlich isotherm model than the Langmuir isotherm model. The sorption energy obtained from D-R model was 13.13 kJ/mol indicating an ion-exchange process as the primary sorption mechanism. Sorption kinetic data fitted with the pseudosecond- order kinetic model and indicated that both external and intraparticle diffusion took part in sorption processes. The RH-g-AA sorbent could be regenerated for more than 5 times by the washing process with 0.1 M HCl without a serious lowering the sorption capacity.
5.
2013.06 서비스 종료(열람 제한)
Establishment of emission concentrations of PCDDs and PCDFs in emission gases from 85 domestic crematories were measured. The relationship between PCDDs/DFs and several factors such as structure, equipment and operational state of the crematory is discussed. Furthermore, emission of PCDDs/DFs from all crematories in korea is estimated. The following results are obtained: (1) total concentration (2,3,7,8- substituted isomers) of PCDDs/DFs was 0.113 ~ 14.34 ng/ Sm3, whose TEQ concentration was 1.815 ng-TEQ/Sm3; (2) total emission of PCDDs/DFs from crematories in korea was estimated to be 1.815 g-TEQ/yr.
6.
2013.06 서비스 종료(열람 제한)
The build-up plan of network to export domestic recycling technologies to developing countries is suggested in and around the Philippines. In the case of developing countries, human network by governmental and non-governmental organizations could be used because the cooperation between government and industry seems to be insufficient. Because developing countries might need financial support, the support from KOICA, EDCF, WB and ADB is necessary. The network build-up plans to export domestic recycling technologies to developing countries are suggested. For this build-up, the following work should be performed: network build-up among the relative organizations and recycling companies; the request to specialists for data collection and spot survey for inadequate data; seminar opening to understand the on-site technology demand and to intoroduce domestic technologies. The following work should be added: securement of political, administrative and social status materials; financial support form international aid organizations. The expected effects through this process are as follows. The first is to support technology export through human network build-up. The second is to secure the introduction cost of recycling technologies. The third is to secure the waste-relative data and materials.
7.
2013.06 서비스 종료(열람 제한)
This research was designed to elucidate the pyrolysis reaction characteristics of waste epoxy printed circuit board (e- PCB). The samples were pulverized after removing coppers by gravity separator. Non-isothermal pyrolysis kinetic results by Thermogravimetric Analyzer (TGA) displayed two apparent reaction regions : 1) fast degradation zone and 2) slow degradation zone. According to batch experiments, solid by-products are responsible for about 78%, while liquid and gas by-products, respectively, represent 13 and 9%. The high content of solid by-products is ascribed to that of SiO2 that is a major components of e-PCB. Liquid by-products exhibit high content of oxygen (19%) and contain the nitrogen of about 1%. It is recommended that gas, liquid, and solid by-products of waste e-PCB would not be applied directly as fuels. Instead, pyrolysis of e-PCB would be applied to recover valuable rare metals and coppers from solid by-products. Application of liquid by-products is likely to be limited due to the presence of brominated oils precursor in liquid byproducts. It is necessary to develop upgrading methods for improving the quality of liquid by-products of waste e-PCB. According to kinetic analysis and product characterization, pyrolysis reaction model of waste e-PCB is accounted for by a series reaction with two independent reactions of two resins: brominated epoxy resins and non-brominated epoxy resins. At the first-stage, two resins are independently decomposed to generate thermally stable intermediates followed by slow degradation of the intermediates to be converted into char.
8.
2013.06 서비스 종료(열람 제한)
The aim of this study was to evaluate various methods for producing high-quality fuel pellets using rape stalk (RS), which is an agricultural waste. RS was used as a raw material for pellets production after three treatments [distilled water (DW), sulfuric acid (AC), sodium hydroxide (AK) solutions]. Then, fabricated pellets with two binder additions [ rapeseed flour (RF), coffee waste (CW)] were examined to evaluate their fuel qualities. Results showed that binder additions (RF, CW) improve the durability and higher heating value for RS-based pellets. The addition of CW greatly decreased ash content for fabricated pellets. Also, all immersion treatments improved all fuel qualities compared to non-immersed treatment. Particularly, DW-immersion had favorable influences on the increases of higher heating value and durability. Two immersion treatments (AC, AK solution) positively influenced the improvements of bulk density and ash content for fabricated pellets. However, they were required to rinse the residue existed on the RS, and consequently the use of DW-immersion might be the most beneficial way to improve the qualities of RS-based pellets. All qualities of the pellets were acceptable for the European agropellet standards (A- or B-grade). Hence, RS can be used as a raw material for the production of agropellets while outdoor exposure of RS or mixing RS with CW or wood sawdust might be help to better agropellets qualities.
9.
2013.06 서비스 종료(열람 제한)
The effect of sewage sludge irradiation and addition of starfish as a dewatering agent on the efficiency of composting was investigated using saw dust as a bulking agent. Results indicates that the temperature of EB sludge cake (electron beam irradiated sludge cake) and EB-SF sludge cake (electron beam irradiated sludge cake mixed with star fish powder) composting piles rose up to 62 ~ 66oC within 1 day and maintained high temperature of 52 ~ 55oC for more than 3 days, which was much higher than that of the control. The electron beam irradiation and addition of star fish accelerate the composting. The control sludge cake composting pile needed 35 days to reach the criteria of mature rate for composting, (Final C/N ratio)/(Initial C/N ratio) of 0.75, while EB-SF sludge cake composting plie required 11 days. This means that maturing compost could be highly improved by irradiating sludge cake or by adding star fish powder. The pH of the composting pile of sludge cake with addition of waste star fish powder rose 1 pH unit higher than that of the control during the entire operation, showing that the star fish has a good buffering capacity. The pH of the final matured compost was above pH 7, satisfying the standard of soil conditioner. The G.I. values of Chinese cabbage and lettuce with composts from EB sludge cake and EB-SF sludge cake composting pile ranged 88 ~ 99, satisfying a safety level (G.I. 80) in plant growth. After 60 days operation for composting 4 different types of sludge cakes, each compost was able to meet the Ministry of Agriculture's Standards of Compost.
10.
2013.06 서비스 종료(열람 제한)
The fuel characteristics, the combustion characteristics, and the kinetic study of sample that had been torrefied at 250 ~ 300oC were investigated for orange peel, rice husks, wood chips, and wood pellets. When higher torrefaction temperature was used, reduction of the yield, and increase in the fuel ratio, and decrease of volatile content were found. As a result, improvement of the fuel characteristics was confirmed. As parameters for the combustion characteristics, initial temperature (IT) was rised slightly because of the high torrefaction temperature of the wood chip, and burnout temperature (BT) showed lowered. The combustion time (tq) of torrefied wood chip (TC) is shorter than raw sample, and unburned carbon generation will be suppressed. The activation energy of the char combustion reaction (2nd) is reduction compared to the raw sample, and the pre-exponential factor was decreased. As a result, the combustion reaction rate constant (k) of the torrefied wood chips, should be determined considering the activation energy and the pre-exponential factor.
11.
2013.06 서비스 종료(열람 제한)
Mechanically pre-treated combustible waste was carbonized at 350 ~ 500oC. In order to determine the optimum carbonization temperature of the produced material, the energy yield, fixed carbon rate, fuel ratio, combustibility index, and characteristics of the coal band were studied. The sample (C425) carbonized at 425oC turned out to be the ideal one in terms of the energy yield and fuel characteristics. Grinding and washing were used for dechlorination of C425. Of these two methods, particle diameter of less than 0.125 mm and washing within two turns displayed chlorine concentration of 0.3%. These results not only satisfied the recommended standard for coal and mixed fuel (0.5wt.%) but also the quality standard for solid fuel (2.0wt.%). In conclusion, carbonization of combustible waste materials resulted in fuel characteristics similar to those of coal, indicating that this process allows for the production of solid fuel with low chlorine content.
12.
2013.06 서비스 종료(열람 제한)
The study aims to analyze economic of biogas plant in transition of recognition that waste resources has become renewable energy. The traditional investment valuation method using the NPV or IRR has a limitation in a sense that uncertainty of the future is not reflected. Hence, the purpose of this paper is to assess the value of the business by taking advantage of the real option. Biogas plant simulation is applied to the case of Garak Market using the binomial options among a variety of real options. With this analysis, it is assessed that operational expand option is the largest of the value of the binomial options.