• Resources Recycling
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• v.7 no.2
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• pp.16-22
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• 1998

Recently, the new technology for the recycling of waste plastics as an alternative he1 of blast furnace ha been developed. In this shldy, the test of plastics injection into a tuyere af the foundry blast furnace were carried out. The injection rate of plastics far this tcst facility war expressed as follows, ${W}_{s}=0.265\frac{{delta}PA}{U}_{g}$, where. Ws, AP, A and Ug are plastic conveying ratc (kgisec), pressure drop between feed hopper and blaqt pressure (alm), cross sectional area of conveying pipe (mi) and superficial velocity of transport air (mhzc) respcctiuely. From the results of semi-continuous test operation during 96 hours, the replacement raho mned out to be 1.38 according to the injection rate of 6. 4 kg-plasticsit-p. With increasing the rate of plaslics injcchon, the content of hydrogen in top gas became increased and the brick temperahlre at bzlly was also increased due to Lhe changes ot the combustion zone shape.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.3
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• pp.65-74
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• 2008

In this study, the composition and physico-chemical characteristics of municipal solid waste (MWS) which was treated in four different area were investigated. It is necessary to measure the characteristics of MSW to build a waste treatment and Refuse Derived Fuel (RDF) facility, the data-base and total managing of the landfill. It was found that the average density of solid wastes is in the range of $78.15-199.8kg/m^3$. This MSW was composed of 8.87% of food wastes, 38.8% of papers, 34.12% of plastics & vinyls, 7.16% of textiles, 0.96% of wood, 1.3% of rubber & leathers and others, respectively. Most of MSW are composed of food, paper and plastic waste and more than 94% was combustible waste. For three components, moisture is 17.38%, combustible component is 69.03% and ash is 6.24%. The chemical element has the high order of carbon, oxygen, hydrogen on the dry basis of wastes. And the low heating value of the MSW which is measured by calorimeter is calculated as 2973.8 kcal/kg and high heating value of the MSW is calculated as 5209.94 kcal/kg.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.533-536
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• 2009

The gasification technology is a very flexible and versatile technology to produce a wide variety products such as electricity, steam, hydrogen, Fisher-Tropsch(FT) diesels, Dimethyl Ether(DME), methanol and SNG(Synthetic Natural Gas) with near-zero pollutant emissions. Gasification converts coal and other low-grade feedstocks such as biomass, wastes, residual oil, petroleum coke, etc. to a very clean and usable syngas. Syngas is produced from gasifier including CO, $H_2$, $CO_2$, $N_2$, particulates and smaller quantities of $CH_4$, $NH_3$, $H_2S$, COS and etc. After removing pollutants, syngas can be variously used in energy and environment fields. The pilot-scale coal gasification system has been operated since 1994 at Ajou University in Suwon, Korea. The pilot-scale gasification facility consists of the coal gasifier, the hot gas filtering system, and the acid gas removal (AGR) system. The acid gas such as $H_2S$ and COS is removed in the AGR system before generating electricity by gas engine and producing chemicals like Di-methyl Ether(DME) in the catalytic reactor. The designed operation temperature and pressure of the $H_2S$ removal system are below $50^{\circ}C$ and 8 kg/$cm^2$. The iron chelate solution is used as an absorbent. $H_2S$ is removed below 0.1 ppm in the H2S removal system.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.4
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• pp.231-236
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• 2011

When the Fukushima nuclear power plant accident occurred in March of 2011, a hydrogen explosion in the reactor building at the 4th unit of Fukushima plants led to a big surprise because the full core of the unit 4 reactor had been moved and stored underwater at the spent nuclear fuel storage pool for periodic maintenance. It was because the possible criticality in the fuel storage pool by coolant loss may yield more severe situation than the similar accident happened inside the reactor vessel. Fortunately, it was assured to be evitable to an anxious situation by a look of water filled in the storage pool later. In the paper, the safety state of the spent fuel storage pool and rack structures of the domestic nuclear plants would be roughly reviewed and compared with the Fukushima plant case by engineering viewpoint of potential severe accidents.

• Nuclear Engineering and Technology
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• v.48 no.5
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• pp.1162-1173
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• 2016

In this paper, we describe a physicomathematical model of the processes that occur in a sodium circuit with a variable flow cross-section in the case of a water leak into sodium. The application area for this technique includes the possibility of analyzing consequences of this leak as applied to sodium-water steam generators in fast neutron reactors. Hydrodynamic processes that occur in sodium circuits in the event of a water leak are described within the framework of a one-dimensional thermally nonequilibrium three-component gas-liquid flow model (sodium-hydrogen-sodium hydroxide). Consideration is given to the results of a mathematical modeling of experiments involving steam injection into the sodium loop of a circulation test facility. That was done by means of the computer code in which the proposed model had been implemented.

• Journal of Radiation Protection and Research
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• v.30 no.1
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• pp.45-54
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• 2005

A dynamic compartment model was developed to appraise the level of the contamination of agricultural plants by accidentally released tritium from nuclear facility. The model consists of a set of inter-connected compartments representing atmosphere, soil and plant. In the model three categories of plant are considered: leafy vegetables, grain plants and tuber plants, of which each is modeled separately to account for the different transport pathways of tritium. The predictive accuracy of the model was tested through the analysis of the tritium exposure experiments for rice-plants. The predicted TFWT(tissue free water tritium) concentration of the rice ear at harvest was greatly affected by the absolute humidity of air, the ratio of root uptake, and the rate of rainfall, while its OBT(organically bound tritium) concentration the stowing period of the ear, the absolute humidity of air and the content of hydrogen in the organic phase. There was a good agreement between the model prediction and the experimental results lot the OBT concentration of the ear.

• Nuclear Engineering and Technology
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• v.45 no.7
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• pp.941-950
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• 2013

The Korean Nuclear-Hydrogen Technology Development (NHTD) Plan will be performing irradiation testing of coated particle fuel at HANARO to support the development of VHTR in Korea. This testing will be carried out to demonstrate and qualify TRISO-coated particle fuel for use in VHTR. The testing will be irradiated in an inert gas atmosphere without on-line temperature monitoring and control combined with on-line fission product monitoring of the sweep gas. The irradiation device contains two test rods, one has nine fuel compacts and the other five compacts and eight graphite specimens. Each compact contains about 260 TRISO-coated particles. The irradiation device is being loaded and irradiated into the OR5 hole of the in HANARO core from August 2013. The device will be operated for about 150 effective full-power days at a peak temperature of about $1030^{\circ}C$ in BOC (Beginning of Cycle) during irradiation testing. After a peak burn-up of about 4 atomic percentage and a peak fast neutron fluence of about $1.7{\times}10^{21}\;n/cm^2$, PIE (Post-Irradiation Examination) of the irradiated coated particle fuel will be performed at IMEF (Irradiated Material Examination Facility). This paper reviews the design of test rod and irradiation device for coated particle fuel, and discusses the technical results for irradiation testing at HANARO.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.1
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• pp.109-113
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• 2016

Techno-economic evaluation of Non-Capture $CO_2$ Utilization (NCCU) technology for the production of high-value-added products using greenhouse gas ($CO_2$) was performed. The general scheme of NCCU process is composed of $CO_2$ carbonation and brine electrolysis process. Through a carbonation reaction with sodium hydroxide that is generated from brine electrolysis and $CO_2$ of the flue gas, it is possible to get high-value-added products such as sodium bicarbonate, sodium hydroxide, hydrogen & chloride and also to reduce the $CO_2$ emission simultaneously. For the techno-economic study on NCCU technology, continuous operation of bench-scale facility which could treat $2kgCO_2/day$ was performed. and based on the key performance data evaluated, the economic evaluation analysis targeted on the commercial chemical plant, which could treat 6 tons $CO_2$ per day, was performed using the net present value (NPV) metrics. The results showed that the net profit obtained during the whole plant operation was about 7,890 mKRW (million Korean Won) on NPV metrics and annual $CO_2$ reduction was estimated as about $2,000tCO_2$. Also it was found that the energy consumption of brine electrolysis is one of the key factors which affect the plant operation cost (ex. electricity consumption) and the net profit of the plant. Based on these results, it could be deduced that NCCU technology of this study could be one of the cost-effective $CO_2$ utilization technology options.

• Journal of Convergence for Information Technology
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• v.9 no.2
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• pp.34-42
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• 2019

In this study, we analyzed the effects of the automatic control system on the reactor operation. The Propyrene Reactor process is complex and typically is inefficient and costly due to the lack of productivity. In this study, a research model was presented with the aim of supplementing obstacles to enhance operational efficiency and increase productivity. The configuration of the existing processes was analyzed to complement the hardware and software systems with original models. The composition of the facility is applied to eight reactor units producing 600,000 ton/year propylene per year. As a result of applying the research model, efficiency of operation was increased, and production volume increased from 90 to 95%, along with 91% Reliability. Future studies will present a research model to improve productivity by 100 percent. In addition, we will study the stability and productivity improvement of PSA (Pressure Swing Adsorption) systems, which are the hydrogen production process of propylene by-products.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.6
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• pp.77-86
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• 2022

Various odor reduction systems are being operated at pig houses to improve livestock odor issues. However, the quantitative evaluation of odor reduction efficiency is not sufficiently conducted. The analysis of factors that affect the reduction efficiency also has not been sufficiently conducted. Therefore, in this study, the reduction efficiency of representative odor reduction facilities (bio-curtain, scrubber) operated by domestic pig houses was evaluated. The odor reduction efficiency was evaluated by sampling the air before and after the odor reduction facility in 6 pig houses. Livestock odors were evaluated for complex odors, ammonia, hydrogen sulfide, and VOC. To find factors for reduction efficiency, temperature, humidity, pH of washing resolution, type of washing water, and ventilation rate was measured. As a result, it was found that the scrubber system had the highest reduction efficiency. The reduction efficiency was found to be affected by the scrubber's washing resolution, filler, operating conditions, and size. Bio-curtains may have problems such as deterioration of fan performance due to ventilation fan load, groundwater pollution, and excessive use of groundwater.