채형준 Hyoung Jun Chae , 안종화 Johng Hwa Ahn

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Abstract

A series of experiments of 0, 10, 20, 30, 40, and 50% food waste compost (FWC) with spent mushroom substrate (SMS) as the substrate for Pleurotus ostreatus (Korea Seed & Variety Service 1021, Chiak cheongsan) cultivation were performed to evaluate the effect of the medium cultures on oyster mushroom cultivation. The best ratio of SMS and FWC was 7:3 in fruit body production (74.0 ± 4.2 g) of P. ostreatus, which was two times higher than that (36.5 ± 3.5 g) in a typical culture medium of sawdust and rice bran (8:2, wet wt/wet wt). Therefore, the medium culture of FWC and SMS was not only proved as the alternative substrate for P. ostreatus cultivation but also significantly increased fruit body production.

Key Words

Food waste compost, Culture medium, Mushroom, Pleurotus ostreatus, Spent mushroom substrate

조병완 Byung Wan Jo , 김철환 Cheol Hwan Kim

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Abstract

This study describes the properties of High Volcanic-Ash Concrete according to the replacement method and ratio of volcanic-ash. For purpose of this study, the tests of slump, setting time, bleeding, compressive strength, tensile strength, modulus of elasticity, heat of htydration, and far-infrared emissivity were performed according to the mix proportion of concrete according to the replacement method (Control Mix, C 10, 20, 35, 50, 70, A10, 20, 35, 50, 70). According to test results, the compressive strength of the concrete using the volcanic-ash as a part of fine aggregate (Mix A) was higher than that of the concrete using the volcanic-ash as a part of cement content (Mix C). The compressive strength of concrete in the mix C decreased with the increase of replacement amount of the volcanic-ash and the compressive strength of concrete for the mix A and mix C increased with the increase of the curing age. The heat evolution of the concrete using the volcanic-ash as a part of cement content (Mix C) was lower than the concrete no using the volcanic-ash. The heat evolution of concrete decreased with the increase of the replacement amount of the volcanic-ash. The far-infrared volcanic ash concrete as well-being concrete may be highly effective for energy saving and anti-bacteria.

Key Words

Volcanic-ash. Replacement method, Replacement rati, Setting time, Compressive strength, Tensile strength

신승규 Seung Kyu Shin , 황현정 Hyun Jung Hwang , 송지현 Ji Hyeon Song

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Abstract

In this study, a two-stage system consisting of a non-thermal plasma process was constructed to simultaneously remove odorous compounds and organic constituents from food-waste sludge. In the first non-thermal plasma reactor, ozone was produced at a concentration range of 200-800 ppm as a function of input energy, and hydrogen sulfide at 10 ppm was treated with removal efficiencies of 60-100%. The ozone-laden gas stream was introduced to the second food-waste sludge reactor, and the oxidation and disintegration of organic compounds took place by the dissolved ozone. During the 4-hour batch experiment, at the same ozone loading condition, 18-61% reduction of total COD was observed depending on the initial concentration, whereas the total amount of organic constituents was identical. In addition, the soluble fraction of the organic constituents increased, and the disintegration ratio was found to be 9-56% after 4 hours. Furthermore, the ionic concentrations of nitrate and sulfate gradually increased, indicating that the dissolved ozone oxidized the odor precursors in the food-waste sludge. Overall, the two-stage system with the non-thermal plasma can be a feasible method to minimize odor emission and to solublize particular organic compounds as well for food waste disposal.

Key Words

Food waste, Odor, Non-thermal plasma, Ozone, Oxidation

천승규 Seung Kyu Chun

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Abstract

The energy productivity of RDF by mechanical treatment and collecting LFG from landfill site was analyzed against the combustible landfill waste in 2009. The analysis showed that the total thermochemical energy potential was 8,700 × 10(12) cal and the greatest part was the domestic waste as 77.1% and vinyl·plastics as 51.6% (4,490 × 10(12) cal). If mechanically treated, the recoverable energy by RDF was 6,711 × 10(12) cal which was 77.1% to total thermochemical energy potential. The total recoverable energy from LFG, considering surface emission, was 2,248 × 10(12) cal. In total energy potential, the total thermochemical energy potential of landfill waste was greater than that of LFG by 273% and, after mechanical treatment, greater than that of recoverable LFG by 263%.

Key Words

Landfill waste, Energy productivity, RDF, LFG, Surface emission

이귀열 Guy Yeol Lee , 오민아 Min Ah Oh , 문소영 So Young Moon , 정준교 Jun Gyo Cheong , 이재영 Jai Young Lee

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Abstract

The electrokinetic remediation is a technology applied to remediate a fine-soil. In this study, the feasibility of the technology was investigated by adapting fine soil after soil washing process contaminated by arsenic. Anolyte conditioning with NaOH on electrokinetic remediation of arsenic-contaminated soil was investigated in the laboratory. Chelating agent was used for As-metal bound to destruct in soil in batch-test. As a result, EDTA is more efficient than Citric Acid (CA) from chelating capacity of Fe, Al and ability of desorption of As when the molarity is 20 mM. Sequential extraction was performed to confirm fraction of Fe-As and Al-As oxides by Onken method. Arsenic-contaminated soil which was mixed with 20 mM EDTA of liquid limit of 120% was filled in lab-scale pilot. Four lab-scale EK(Electrokinetic)-systems were operated for 408 hours. Tap water, 0.025 N, 0.03 N and 0.1 N NaOH are used for anolyte. After experiments, soil in the cell was sliced into 5 sections and each section was used to analyze As-concentration. As a result, removal efficiencies of arsenic were: 21.48% for EK-1, 35.26% for EK-2, 50.33% for EK-3, 67.43% for EK-4.

Key Words

Etectrokinetic, Arsenic, Chelating, Fine soil, Soil washing

박상원 Sang Won Park , 이민구 Min Gu Lee , 정석재 Suk Jae Jeong , 박진원 Jin Won Park

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Abstract

Recently, waste materials are important as a one of the alternative energy sources in heavy energy using industries. Since cement industry is an heavy energy using industries it has to consider the alternative energy. Heavy energy using means that GHGs emissions a lot. Among them, the cement industry is one of the big energy consumption industries. This study aim is that assessment of CO2 emissions and its reduction potential at Portland cement industry by selecting energy optimization technologies. we analyzed CO2 emission in the sintering process by using waste materials. Considering the energy balance ratio of waste materials commitment to the potential reduction of CO2 emissions were analyzed. We selected a waste tires and recycle fuel. Because it has low emission factors than coal. We added a scenario that assumed to use two alternative fuels (waste tires, recycle fuel) simultaneous. As a result, relatively low emission factors for recycling fuel to replace coal increased, the amount of carbon dioxide emissions were found to decrease gradually. This result indicate that lower emission factor waste materials fuels could suggest CO2 emissions reduction feasibility of Portland cement process. If waste materials used in sintering process, the voluntary goal of Korea Cement Industrial Association can be possible(greenhouse gas emissions 5% reductions: IN 2005 in comparison 2015).

Key Words

LEAP model, CO2 emission, Portland Cement, System Dynamics, Renewable Energy

짜오신 Xin Zhao , 윤석표 Seok Pyo Yoon

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Abstract

To treat odor (ammonia) generated from composting process of small size sewage sludge treatment system, a study was conducted on the biofilter system for ammonia removal. As filling materials of biofilter, compost, polyurethane foam, and compost and polyurethane foam mixture were used. Ammonia was selected as a target odor component because high concentration of ammonia gas was measured during sewage sludge composting. Effect of EBRT (Empty bed retention time) and input concentration of ammonia gas on the treatment efficiency of biofilter were studied. In case of 50% compost and 50% polyurethane foam by volume as biofilter media, and 60 seconds EBRT, removal efficiency of ammonia gas showed 95.2%. For 60 seconds EBRT, input ammonia concentrations of 300, 600, 900, and 1200 ppm showed 98.0, 99.2, 97.3, and 99.4% removal efficiency, respectively. From the results, as filling media for ammonia gas removal, compost and polyurethane foam mixture showed good removal efficiency, and relatively small subsidence of filter media. By installing condensate separation apparatus between composting unit and biofilter, efficient ammonia removal was achieved. In practical operation, the compost generated from sewage sludge composting process can be used as filling media for biofilter.

Key Words

Ammonia, Composting, Biofilter, Polyurethane foam

손봉호 Bong Ho Son , 어성욱 Seong Wook Oa

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Abstract

The accumulation of Pb shot deposited on land at clay target shooting sites has been identified as a source of Pb contamination. A clay target shooting site was surveyed to assess the degree of Pb contamination. Soil samples were collected in the shot-fall area along to perpendicular to the line of traps at the site. Pb concentration of each soils were analyzed by modified method for sequential extraction designed for sediment analysis by Atomic Absorption Spectrophotometry (AAS), The Pb partitioning tests from those soil samples show that the content of exchangeable are 92.4% for falling area and 82.9% for trap area, also the content of bound to other materials is 7.6% for falling area and 17.1% for trap area, relatively. To remediate the contaminated site, acid flushing process could be applicable and the removal efficiency of Pb soil depends on its particle size. From the lab scale acid flushing test, Pb removal efficiencies were achieved up to 100% (> 2.8 mm), 88 ~ 91% (0.075 ~ 2.8 mm) and 69 ~ 78% (< 0.075 mm). As a result of this study, acid flushing should be considered an effective remediation process and collaborative particle partitioning could be a key factor to get an optimum flushing efficiency.

Key Words

Acid flushing, Clay target shooting site, Lead (Pb) contamination, Particle partitioning, Soil Remediation

박상원 Sang Won Park , 조호용 Ho Yong Jo , 이민구 Min Gu Lee , 박진원 Jin Won Park

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Abstract

South Korea was excluded from parties to Greenhouse Gases (GHGs) emission impulsive reduction but as it is considered the 10th rank carbon dioxide emission in the world. According to COP16 in Mexico, South Korea did not include in Annex I. Nevertheless, Korea government has responded to activity action of the climate change. Carbon dioxide among GHGs is well known due to the use of fossil fuels. Most of CO2 emitted in South Korea consists of about 83% of the total GHGs emissions because of the use of fossil fuels. Recently annual energy consumption of fossil fuels increased 3 times in comparison with 20 years ago. To respond to an advent of new high crude oil price age and GHGs emissions reduction, South Korea government announced "the first National Energy Basic Plan" in 2008. Designating new & renewable energy of 11 items, Korea government plans to enlarge consumption rate of it from 2.4% in 2007 to 30% by 2020. To motivate new renewable energy use, South Korea government also announced ``Refuse Derived Fuel Comprehensive Measures`` because Korea has a limit on refuse landfill site. In Korea case, energy sources of pre-energy depend on the imports. Using LEAP (Long-range Energy Alternative Planning system) model, we quantitatively analyzed the GHGs emission reduction effect and potential by applying the alternative energy. According to an evaluation of GHGs emissions reduction, as we replace coal with RDF and RPF. And we added to 1 more scenario about considering economic. As a results, we estimated to RPF has the most reduction potential in CO2 emissions. However it is more expensive than the others. So we suggest that waste energy is considered to combine RPD and RDF for achieving the government plan.

Key Words

LEAP model, CO2 emission, Waste management plan, Renewable energy

조현정 Hyun Jung Jo , 황용우 Yong Woo Hwang , 박지형 Ji Hyoung Park , 강홍윤 Hong Yoon Kang

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Abstract

Environmental impact for remanufacturing was evaluated using Life Cycle Assessment (LCA) methodology in this study. Parts of automobile and toner cartridge which are the most typical remanufacturing industries were selected for the case study. Several selected parts of automobile to carry out LCA were a Constant Velocity joint (CV joint), a starting motor, an Alternating Current generator and an air compressor. In the toner cartridge case, A4/black, A3/black, A4/color, A3/color were selected. The system boundary was set up from gate to gate stage of the parts. Life Cycle Inventory Database (LCI DB), which has been developed by Ministry of Knowledge Economy (MKE) and Ministry of Environment (ME) in Korea, was used for inventory analysis. Impact categories were divided into 8 categories considering Korean situation: abiotic resource depletion, global warming, ozone depletion, acidification, eutrophication, photochemical oxidant creation, ecotoxicity and human toxicity. The results for each new and remanufactured part were compared. In addition, CO2 emission of each part was calculated through results of the inventory analysis.

Key Words

Remanufacturing, Life cycle assessment, Parts of automobile, Toner cartridge

김나랑 Na Rang Kim , 유영돈 Young Don Yoo , 김병환 Byung Hwan Kim , 김정헌 Jeong Heon Kim , 김형택 Hyung Taek Kim

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Abstract

The presence of HCl in gasification system relates to corrosives problems that are caused by the deposition of HCl on gas turbine blades and heat exchanger surfaces. In this paper, the HCl removal with sorbents was studied in a fixed reactor at 250~450˚C. At the temperatures of 250~450˚C, the chloride removal capability of sorbent increases with increase temperature. The IAE-N1 sorbent self-prepared has highest chloride sorption capacity of 279.3 mg-HCl/g-sorbent under conditions of 450˚C, 3,000 h-1 space velocity, and 1,000 ppm HCl input concentration.

Key Words

High-Temperature Cleaning, HCl Removal, Waste-Derived synthesis gas

김승도 Seung Do Kim , 김의건 Eui Kkun Kim , 진병복 Byong Bok Jin

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Abstract

This paper introduced a new estimation method of greenhouse CO2 emission from incinerator using high heating value of municipal solid wastes (MSW). Previous methodology used carbon contents of fossil fuel origin to estimate CO2 emission from incinerator, demanding several information such as dry weight of MSW, carbon content, and ratio of fossil fuel origin carbon. However, the method using high heating value requires less information, thus reducing the uncertainty of estimation results. Sensitivity analyses were carried out to elucidate what parameters can affect the accuracy of CO2 emission results. Dry weight and heating values affected their accuracy most significantly. It is, hence, necessary to obtain the most reliable results for the two key parameters. The CO2 emission results derived from high heating values were compared with those from the IPCC methods, demonstrating the deviations of -1.04% and -2.78% for the MSW incinerators of Chuncheon City and Kyoreong Gun, respectively. The new estimation method using high heating value of MSW is believed to be quite reliable alternative method for estimating greenhouse CO2 emission from MSW incinerators.

Key Words

CO2 emission, Heating value, Municipal solid waste, Incinerator

박수호 Soo Ho Park , 한빙 Bing Han , 이우범 Woo Bum Lee , 김성욱 Sung Ug Kim , 김종오 Jong O Kim

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Abstract

The objective of this study was to determine the possibility of phosphogypsum (PG) recycle as an embankment material by eco-toxicity experiments in both batch and column tests. Artemia salina and Daphnia magna were selected for the eco-toxicity experiments. At a 24 hr acute toxicity test in a batch condition, immobilization rate of the Artemia salina was 2.5% at 50% phosphogypsum used, whereas the rate was increased to 5% at 100% phosphogypsum. The immobilization rate ranged from 27.5 to 35% after 48 hr. For the Daphnia magna during a 48 hr test, the immobilization rates at 30% and 50% mixed were 25% and 45%, respectively. For the Artemia salina at the column test, the addition of the phosphogypsum at 50% decreased to pH 6.8. No immobilization rates were observed for 13 weeks. It was observed that the effective concentration (EC50) of Artemia salina by leachate from PG100 was 32.45 mg/L. This study suggested that phosphogypsum generated from fertilizer productions could be recycled at low concentrations with soils.

Key Words

Artemia salina, Daphnia magna, Embankment material, Phosphogypsum, Toxicity