간행물

한국폐기물자원순환학회지 KCI 등재 Journal of Korea Society of Waste Management

권호리스트/논문검색
이 간행물 논문 검색

권호

제31권 제1호 (2014년 1월) 14

Original Paper

1.
2014.01 서비스 종료(열람 제한)
In this study, PCBs and PAHs in waste oils and liquid fuel waste were analyzed. About 48 samples were collectedand analyed, for hazardous substances such as PCBs, PAHs by GC/ECD and GC/MSD. According to the analysis, seventypes of PCBs concentration was found in the range of 0.13~220.77mg/kg. The highest concentration level was foundin waste insulating and heat transmission oils (EWC 13 03 08), as 220.77mg/kg. Comparing the level of PCBs to othercountries, PCB concentration in this study was lower than that of China but higher than Japan. PAHs concentration wasin the range of ND~1,380.0mg/kg for Naphthalene, ND~1,570.0mg/kg for Phenanthrene, ND~321.2mg/kg forAnthracene, ND~44.1mg/kg for Benzo[a]pyrene, ND~80.8mg/kg for Fluoranthene, ND~14.3mg/kg for Benzo[a]anthracene and ND~8.7mg/kg for Benzo[b]fluoranthene. The concentration 7 PAH in the waste oil showed the orderof Automotive oil>Hydraulic oil>Cutting oil>Machine oil. The Benzo(a)pyrene which is known as high carcinogeniccompound was detected with low concentration. Compared to other waste from other countries, the concentration of thisstudy is higher than that of Japan and lower than that of China. The PAHs concentration was lower than Automotiveoil, Hydraulic oil, Cutting oil, Machine oil, in Spain.
2.
2014.01 서비스 종료(열람 제한)
In this study, the experiments which use the dry absorbent has been executed in order to find optimum HCl absorptionconditions. The absorbents in this experiment were Ca(OH)2-A, Ca(OH)2-B and CaO. They were put in a fixed-bed reactor.The reaction temperature of HCl/Ca(OH)2 systems were between 200~400oC and those of HCl/CaO systems werebetween at 500~700oC. The reaction gases were HCl and N2 mixtures (3000ppm). The reaction gas of 2L·min−1 wasfed into the reactor. As temperature increased, the conversion ratio of HCl in Ca(OH)2 particles also increased.Consequently, Ca(OH)2-B showed the maximum conversion ratio of 19% at 400oC. CaO also showed the similar tendencywith the result of Ca(OH)2. In case of same particle sizes, as reaction temperature increased, the reaction rate constant(k) also increased. The highest reaction rate constant of Ca(OH)2-B was 3,952min−1 at 400oC. All absorbents in thisexperiment showed that the reaction rate decreased with increasing the size of the particles at each temperature condition.The kinetics of the reaction between sorbents and HCl molecules showed that the activation energies were about 2.71~6.85kcal·mol−1 (averager 4.53kcal·mol−1) for Ca(OH)2-A, about 1.3011.51kcal·mol−1 (average 6.10kcal·mol−1) forCa(OH)2-B, and about 2.5314.3kcal·mol−1 (average 6.91kcal·mol−1) for CaO depending on conversion ratios.
3.
2014.01 서비스 종료(열람 제한)
The aim of this study is to evaluate the reduction costs of waste treatment and the increasing benefits of recyclableaccording to the volume-based waste fee system. The effects of waste treating costs reduction is calculated by the collectionand transport costs, Landfill costs and Incineration costs. These are calculated by each reduction amounts and disposal unitprices through year 1995~2009. The effects of recycling benefits of each item is calculated by variation amount of eachrecycling items and each unit prices. The time value of money is also considered to get both total waste treating reductioncosts and the present value of recycling items. In addition, the improvement in low percentage of ‘financial independenceof cleaning’ and ‘residents burden rate’ are needed to actualize the volume-based waste fee system. The reason is that thesemake hard to cover whole cleaning budget by itself. Therefore, it is true that raising the price of bag of the volume-basedwaste fee is unavoidable and differential rate of raising the price of bag is needed. This paper deducts three suggestions toraise the price of Volume-based Waste Fee System bag to develop the Volume-based Waste Fee System further more.
4.
2014.01 서비스 종료(열람 제한)
This study was performed to investigate the feasibility of ion-exchange resins as soil amendment. To select resins, weinvestigate four kinds of ion exchange resins, which ions have the most adsorption efficiency of ions (N+, PO4−, K+). Inthe Cation (H+) vs Anion (OH−)=1:2 (w:w), it showed that the highest N, P, K adsorption efficiency was about 80%and reached pH 6~7 & EC 1~2dS/m after 20min. The ability to maintain ion adsorption, it was investigated that thegentle curve of the residual ion ratio of nitrate nitrogen, available phosphorus, exchangeable potassium was maintained.On the other hand, the control (Slow release fertilizer) was significantly reduced under artificial rainfall conditions. Inaddition, the results of three consecutive crop test were showed that the growth of crops decreased 41.8% than the earlygrowth in the control group, whereas decreased 8.3% in the treatment group (ion exchange resins). According to the resultsof soil analysis, it was reduced that the fertilizer ingredients (N 94%, P 74.5%, K 98.6%) in the control and reducedfertilizer ingredients (N 64%, P 60.3%, K 58.4%) in the treatment. Overall, it was estimated that the Ion-exchange resinscould be used as a soil amendment.
5.
2014.01 서비스 종료(열람 제한)
Pyrolysis of biomass is the thermal decomposition of its carbohydrate structures into numerious hydrocarboncompounds, light gases and carbon-rich solid residue. Understanding the pyrolysis characteristics is essential asfundamental data for various thermo-chemical conversion of biomass. This study investigated slow pyrolysis of fourIndonesian biomass (sugarcane bagasse, cocopeat, palm kernel shell (PKS), umbrella tree) for a temperature range of300~600oC. With increase in temperature, all samples showed a decrease in the biochar yield as more compounds werereleased as vapors increasing the bio-oil and gas yields. The biochar became more carbon-rich with a carbon content of85% or higher at 500oC. However, the product yields and properties showed large variations between the samples.Cocopeat had the highest biochar yield, while wood and baggasse had the highest bio-oil yield. Despite the low massyields, the biochar of wood and bagasse had the best quality in terms of macro-pore and micro-pore development, whichis a key property for its applications as adsorbent, soil ameliorator, as well as fuel. The bio-oil did not have a sufficientlyhigh HHV for use as main fuel, but could be utilized through co-firing or slurry production with biochar. In the lightgases, CO and CO2 were dominant, but could be burned on-site to supply the heat required for pyrolysis.
6.
2014.01 서비스 종료(열람 제한)
Quality of GHG emission from solid waste disposal depends on level of activity data. Activity data of solid wastedisposal is mass of waste disposal and waste composition. Waste composition is one of the main factors influencingemissions from solid waste disposal. According to GHG target management in Korea, uncertainty of activity datadetermined by level of tier. We suggest minimum sample number for analysis of waste composition. In result, we suggestto revise the guideline for GHG target management that minimum sample number for analysis of waste compositionmust be over 73 times during 3 years for total uncertainty of waste composition must be less than or equal to 7.5%(Tier 1 level).
7.
2014.01 서비스 종료(열람 제한)
Six lab scale reactors were designed having the height of 1/20 scale of real burial site and each reactors contained aleachate collecting system. Cattle and pigs were buried in these reactors, and leachate was collected to determine theconcentration of antibiotics. Leachate samples were collected periodically over a period of 24 weeks along with the trendof temperature and decomposition degree. Sulfachloropyridazine was detected in the initial leachate (4 and 8 weekssamples) from the cattle 1 and cattle 2 reactors, as 56µg/L and 312µg/L respectively and thereafter it was not detectedin leachate (16~24 weeks samples). Most of the antibiotics concentration were detected higher in leachate released inbetween 4~8 weeks. However, sulfadimidine was detected throughout 24 weeks in cattle 1 reactor, with the range of2.2~17.5µg/L. As a result of comparison with different aqueous environment, improper management of carcass burialsites may result in both surface water and groundwater contamination. To protect public health and to prevent/minimizethe negative impacts of contamination by antibiotics, proper environmental monitoring of leachate before and after carcassdisposal is necessary.
8.
2014.01 서비스 종료(열람 제한)
In order to improve the potential for the resource circulation of household waste that is being handled by localgovernments within major cities, this research has analyzed the characteristics of waste produced and presented a blueprintfor a coding system for household waste, to enable the operation of a resource circulation management processing systembased on this analysis. The coding system –format #-#-##-#-#– has been developed to mirror the 6-digit number codesused nationally for categorizing industrial and harmful waste. In order to boost resource circulation, the household wastecoding system has been composed as such: ‘waste production category>kind of waste>waste item>circulation grade>related industry,’ to offer a more effective means of managing household waste. A waste management processing systemconstructed according to the coding system developed through this research will not only make waste management simplebut serve to promote resource circulation. This system has been applied for the resource circulation management ofhousehold waste in Nowon-gu in Seoul. As a result of this application 6 categories of waste production, 20 kinds of waste,155 waste items, 9 circulation grades and 26 connected industries were codified. Going forward, on the basis of thisresearch the code systems used in a wide range of local governments for the classification of household waste shouldbe researched and a means of standardization formulated. In addition there is a need for research to be conducted intointegration with existing industrial and harmful waste coding systems.
9.
2014.01 서비스 종료(열람 제한)
The development of functional finishes for the improvement of indoor air quality is one of important issues in the fieldof building materials. Indoor air quality can be affected by gases, particulates, microbial contaminants or any mass thatcan induce adverse health conditions. The purpose of this study is to develop eco-friendly internal material of acrylicemulsion mortars using light-weight aggregate carrier which contains pyroligneous liquid. Four types of light-weightaggregates (perlite, vermiculite, charcoal and zeolite) those are functionally used in interior finishing materials are selectedand the properties such as flowability, adhesion, water absorption coefficient, crack and impact resistance are evaluatedin accordance with KS F 4715. As a result, the properties of acrylic emulsion mortars using light-weight carrier in thisstudy are satisfied with KS requirements. Among the four types of mortars with light-weight carrier, properties of acrylicemulsion mortars using zeolite carrier is more excellent than those of other light-weight carriers.
10.
2014.01 서비스 종료(열람 제한)
Leachate generation is an inevitable consequence of waste disposal in landfills. Numerous mathematical modelshave been developed to simulate leachate occurrence and behavior. However, these models have been successful toa limited extent because of uncertainties associated with biological, chemical, and physical processes in landfills. Inorder to predict the generation of leachate in closed landfills, correlation analysis was conducted based on precipitationin this paper. Regression analysis for deriving the correlation between precipitation and leachate generation rate wasperformed in a closed landfill. As a result, we found that the amount of leachate which is generated regardless ofprecipitation should be considered as well as the percolation of precipitation. Also, it was possible to make an fairlyaccurate prediction of leachate generation only using precipitation data in this paper. It is suggested that the amountof leachate generation is 4~8% of monthly precipitation and about 25,000m3/month of base generation regardlessof precipitation. However, the predicted values of leachate generation for the high precipitation seasons were not closeto those observed.
11.
2014.01 서비스 종료(열람 제한)
Analyzing results of exhaust gas of solid fuel burning are investigated with measuring position in a pilot scale MILD(Moderate and Intense Low oxygen Dilution) combustor using high temperature exhaust gas recirculation. Flue gas hasbeen measured at exit of combustion chamber and stack, especially. Oxygen concentration measured at stack is higherand carbon dioxide concentration is lower than that measured at exit of combustion chamber, because air flows into theflue gas from the post-treatment facilities, such as gas cooler and bag filter, due to negative pressure caused by inducedblower. Low carbon dioxide concentration can cause an error which estimates higher air ratio than actual air flow rateneeded for complete combustion. Average calculated concentration of measured nitric oxide and carbon monoxide forreference concentration of 6% oxygen have no notable difference with measuring position. But, time resolution of thedata measured at exit of combustion chamber is better than that measured at stack. It is confirmed that MILD combustionof solid fuel of pulverized coal using high temperature exhaust gas recirculation can reduce dramatically nitric oxideemission.
12.
2014.01 서비스 종료(열람 제한)
It is expected that construction waste include a waste concrete is continuously increase each year in the future. Theamount of construction waste is a lot and according to the nature of construction waste, it does not have a seriousenvironmental pollution and hazards. Therefore it is used as recycled aggregate directly or through a simple intermediatetreatment. The purpose of this study, recycled aggregate concrete used in a building structure system. Thus this studyfigure out which physical and mechanical characteristics of recycled aggregates concrete. According to replacement levelof recycled aggregates compared with natural aggregate, examine a life cycle CO2 emission and review cost efficiencyfor the practical use of recycled aggregate concrete. The result of this study that recycled aggregate concrete decline aCO2 emission and decrease material cost when a replacement level is increase. Carbon dioxide emissions per unit volumein aggregate by dry process according to substitution ratio compared with 0%, in 30% is 0.10%, in 50% is 0.34%, in100% is 0.58% reduce. Aggregate by wet process according to substitution ratio compared with 0%, in 30% is 0.02%,in 50% is 0.20%, in 100% is 0.35% reduce.
13.
2014.01 서비스 종료(열람 제한)
In order to prevent the spreading infectious disease in domestic animal, livestock excretion should be controlled bysterilization. The basic concept of sterilization can be described by thermal treatment under vacuum state. From the basicconcept of sterilization, livestock excretion can be converted to produce renewable energy using the method ofcarbonization and the method of carbonization can also be reduced greenhouse gas effectively. Chicken manure is usedas a sample of renewable energy source in the carbonization reactor. The basic energy characteristics of chicken manuresuch as proximate analysis, and heating value are estimated. The carbonization residue of chicken manure which isobtained from carbonization experiment is subject to several analyses in order to examine the energy characteristics suchas heating value, fuel ratio, combustible index and yield. As increased carbonization temperature, both heating value andfuel ratio (fixed carbon/volatile combustible) of the residue are increased up to 350oC but yield of the residue is decreased.From the results of bulk density, fuel ratio and total heating value of the residue, the optimal conditions of carbonizationtemperature and time can be decided by about 350oC and 15min. Since the residue of chicken manure can not be satisfiedwith the standard of the third grade of solid fuel product, it is desirable that chicken manure be modified with othermaterials to improve an energy potential and to use as a clean fuel.
14.
2014.01 서비스 종료(열람 제한)
There have been a lot of efforts to increase recycling rate by more utilization of end of life vehicles (ELVs) in Korea.The target of recycling rate was set to 85% until 2014 and 95% after 2015 with including up to 10% of energy recovery,according to the law of “regulation about resource recycling of electrical and electronic products and automobiles”.Therefore, to achieve 95% of recycling rate by the year of 2015, the automobile and recycling industries should developan innovative technology to treat automobile shredder residues (ASRs) by efficient means of reduction or conversion toenergy, which were generated as final left-over after recovering all the valuables from ELVs. As one of the options toconvert to energy forms, the gasification of them was proposed. In this study the gasification experiment was performedusing ASRs at fixed-bed reactor with a capacity of 1kg/hr, at different temperatures of 800, 1,000 and 1,200oC, and atequivalence air ratios ranging from 0.1 to 0.5. The syngas (H2+CO) yield from ASR gasification experiment was obtainedup to 86% in maximum and about 40% in minimum in the experimental conditions given. There was a trend that theamount of syngas increased with elevated temperatures and the calorific value also showed similar trend with syngasproduction.