Zinc flake가 적용된 도료의 방식성능 평가에 관한 연구

장정국,임준혁,정헌석 한국공업화학회 2011 한국공업화학회 연구논문 초록집 Vol.2011 No.1

플라이애시와 슬래그 혼합 알칼리 활성 시멘트의 미세구조 특성

장정국,Jang, Jeong Gook 인천대학교 도시과학연구원 2018 도시과학 Vol.7 No.1

This study investigates microstructural characteristics of alkali-activated cements incorporating slag and fly ash. Samples were prepared with four fly ash:slag ratios, i.e., 100:0, 90:10, 70:30 and 50:50, and they were synthesized by using an alkali activator. Microstructural characteristics of the alkali-activated cements were determined by XRD, TGA, SEM, N2 gas adsorption/desorption methods, and compressive strength test. The results showed that properties of alkali-activated fly ash/slag were significantly affected by slag contents. Alkali-activated fly ash/slag with slag content of 30-50% showed higher compressive strength than ordinary Portland cement paste. An increase in slag content resulted in a denser microstructure, which composed of amorphous gel, therefore contributed to strength development of the material.

목재 건조공정에서 발생되는 휘발성 유기화합물(VOCs)에 관한 연구

장정국,박동근,김미란,서용수,이제근 한국폐기물자원순환학회(구 한국폐기물학회) 2003 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2003 No.-

[신진연구자 소개] 황주영

장정국 한국콘크리트학회 2020 콘크리트학회지 Vol.32 No.1

[포스터 발표] 목재 건조공정에서 발생되는 휘발성 유기화합물(VOCs)에 관한 연구

장정국,박동근,김미란,서용수,이제근 한국폐기물자원순환학회 2003 한국폐기물자원순환학회 학술대회 Vol.2003 No.1

도시 폐기물 소각공정에서 다이옥신류 저감방안에 관한 연구

장정국,이제근,이기호,전해수 한국폐기물자원순환학회 1994 한국폐기물자원순환학회지 Vol.11 No.3

유동층 연소로에서 유·무연탄 혼합연소시 유연탄 혼합비에 따른 연소효율 증진에 관한 연구

장정국 東西大學校 2001 동서논문집 Vol.7 No.-

Combustion characteristics of blended coal of anthracite and bituminous are investigated in a laboratory scale fluidized bed combustor (10.8㎝ ID and 170㎝ height). The dry basis higher heating values of anthracite and bituminous coal used in this study are 2810 cal/g and 6572 cal/g, respectively. The Bituminous coal which has low ash content and shrinkage characteristics in combustion process is not remained in the fluidized bed. However, the anthacite coal is able to use a bed material and accumulate in the bed. Then the bed pressure increases with operating time. In order to operate continuously, therefore, the bottom ashes have to discharge by under drain pipe. The elutriation rate of fine particle collected tends to increase with the superficial gas velocity, however, the under drain rate of bottom ash increases in fluidized bed combustion of Bituminous- Anthracite coal blend. The relative fraction of anthracite coal in the find coal blend and the fraction of combustion of fine particle in the freeboard increase with the mixing ratio of bituminous coal to blended coal, therefore, the elutriation rate of fine particle collected tends to decrease. Due to the behavior characteristics of particle in the fluidized bed, the promotion effect of combustion efficiency with mixing ratio of bituminous coal is higher than the calculated combustion efficiencies of antharacite and bituminous coal fluidized bed combustion under the same operating conditions, i.e. about 3.5 - 12.4%. The optimum mixing ratio(MR) of butuminous coal determined is around of 0.75 in this study.

소각공정에서의 대기오염물질 배출농도 예측에 관한 연구

장정국 東西大學校 1996 동서논문집 Vol.2 No.1

최근 심각한 사회문제로 대두되고 있는 각종 환경오염 물질들은 인간 및 동식물의 생존에 매우 유해한 영향을 미치고 있다. 이러한 물질들중 대기오염 문제를 야기시키는 ?? 및 중금속 화합물등과 같은 대기오염물질은 그 발생량의 80% 이상을 초과하는 많은 양의 오염물질이 화석연료의 연소(화력발전소, 차량, 산업체 및 가정난방 등) 및 각종 폐기물의 소각과정으로부터 발생하고 있는 실정이다. 따라서 대기오염물질의 발생량을 줄이기 위해서는 연료 및 폐기물의 종류에 따른 최적의 연소기술 및 후처리 설비기술의 개발이 필연적으로 이루어져야만 한다. 따라서 본 연구에서는 열역학 평형모델을 이용하여 폐기물 등의 소각공정에서 발생하는 대기오염물질 및 중금속 물질의 배출농도를 미리 예측하므로써 이러한 오염물질의 배출량을 최소화할 수 있는 소각공정에서의 최적 조업조건을 설정하는 데 필요한 기초자료를 확보하고자 모델 시뮬레이션을 행하였다. To predict the emission concentrations of trace metal compounds and air pollutants during incineration process of waste, the simulation was carried out using a thermodynamic equilibrium model. The sewage sludge was selected as typical waste under the condition of T=400-1200K, P=1.1atm. and ??. During waste incineration, the nature of flue gas varied markedly accordingly to temp condition. Lead compounds in the flue gas was discharged to solid phase PbSO4 below 1000。K, while gas phase Pb and PbO wasdominated upper 1000。K. In case of Cl contained in the waste, however, lead compound was evaporated to lead chloride. Under 600-1200。K and 1.1 atm reaction of Cr in the waste lead to the formation of chromium oxide(Cr2O3(s)). It is assumed that the chromium was formed as volatile chromium chloride such as CrCl2, CrCl3 and CrCl4 in presence of Cl. However, ash particles discharged from the incinerator was contaminated by chromium compounds such as Cr2O3 in combustion condition. Cadmium and zinc compounds were converted to metal sulfates upto 1000。K. With increase of operating temperature, Cd and Zn compounds were converted to Cd(g) and ZnO(s) respectively. And then it resulted in increase of SO2 concentration in the combustion gases. Therefore, it was found that incinerator should be operated as possible as low temperature in order to reduce air pollutant emission and to capture the metal compounds in form of solid phase in the ash particles. When incinerating the wastes which containe a large amount of trace heavy metals and hazardous materials, it was expected that FBC is the most effective method because that it is the readiest way to combust the waste in the low-temperature.

목재 건조공정 배기가스의 특성에 관한 연구

장정국,박동근,김미란 東西大學校 2001 동서논문집 Vol.7 No.-

This study was performed to provides the characteristics of flue gas producted from wood drying process. Generally, the flue gas producted from wood drying process was elutriated with a large amount of moisture and odorous compounds such as BTX and ethanol. Therefore, it is very difficult to select and design of flue gas control devices. In order to optimum design and selection of control devices, have to investigate the various parameters such as temperature, moisture contents and flow rate of flue gas. When the wood is almost dry(<10% moisture), the moisture contents of flue gas were very high (about 18.2 V/V%). It is equivalent to 320 ton/day moisture as 1100 ton wood/day induce to the drying process. The temperature of flue gas ranges from 140℃ to 150℃ in each dryer stack with exception of the input site of wood(about 110℃). Thevelocity of flue gas In each stack ranges from 1.7 to 9.7 m/sec. About 40 VOCs in the flue gas were analyzed, and the concentrations of major VOCs(ppm) were as follows respectively; benzen: 0.054∼0.052, toluene: 1.011∼2.547, ethylbenzen: 0.472∼2.023, m,p-xylene: 0.504∼3.245, styrene: 0.015∼0.148, o-xylene : 0.271∼1.097, ethanol: 11.2∼32.5, α-pinene: 0.908∼10.578, β-pinene: 0.982∼14.278.

순환유동층 석탄재의 활용 기술과 광산 채움재 관련 규격 동향

장정국,지상우,안지환 한국자원리싸이클링학회 2017 資源 리싸이클링 Vol.26 No.2

Circulating fluidized bed combustion (CFBC) ash is one of useful mineralogical resources having abundant content of free lime and anhydrite, and has a self-cementitious property. Recently, considerable interest has been gained regarding the utilization of CFBC ash, along with its use in mine backfill and reclamation. Prior to adopt the use of CFBC ash in the mine backfill technology, discussion on the technology and related specification is prerequisite in the future. This paper presents a review on studies in the emerging technology of CFBC ash utilization, and provides useful information with regard to the specifications for mine backfills utilizing CFBC ash. 순환유동층(CFBC) 보일러 방식의 석탄화력발전소에서 발생하는 석탄재는 유리 석회와 무수석고의 함량이 풍부하고 자경성을 가지는 것을 특징으로 하는 물질로서 유용하게 활용해야 할 자원 중 하나이다. 최근 CFBC 석탄재를 포함하여 석탄화력발전소 부산물을 활용한 광산 채움 기술 및 광해 관리에 대한 관심이 점차 증가하고 있는 가운데, CFBC 석탄재를 광산 채움 분야에 적용하기위해서는 기술에 대한 검토와 함께 관련 규격에 대해 향후 충분히 논의를 거쳐야 할 여지가 있다. 이를 위해, 본 논문에서는 CFBC 석탄재의 유효 활용 기술에 대한 연구동향을 소개하고, 광산 채움 분야의 활용을 위해 국외의 규격 동향을 고찰한 후 연구방향 및시사점에 대해 정리하였다.