• Title/Summary/Keyword: Bloating

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Effects of Additives and Sintering Method on the Properties of Light Aggregate Prepared from EAF Dust/Clay (첨가제와 소결방법이 EFA Dust/점토 소결체의 경량화에 미치는 영향)

  • 권영진;이기강;김유택;김영진;강승구;김정환;박명식
    • Journal of the Korean Ceramic Society
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    • v.40 no.3
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    • pp.309-316
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    • 2003
  • EAF(Electric Arc Furnace) Dust classified as special wastes containing heavy metal contaminants may cause to damage an environment such as underground water contamination if they were not treated properly. The possibility of producing the porous sintered body made from EAF Dust/clay composition system was studied. Mixing of EAF Dust and clay was carried out using wet-mixing process and two different sintering methods such as rapid and normal heat treatment were tried. By observing density, porosity and microstructure of sintered bodies, it was found that the bloating phenomenon depend on the contents of C, where the liquid phase occur or not during the sintering process. To obtain a light-aggregate of porous body due to bloating, the rapid heating was better than the normal heating at sintering process.

Bloating Mechanism of Artificial Lightweight Aggregate for Recycling the Waste Glass (폐유리를 재활용한 인공경량골재의 발포기구)

  • Kang, Shin-Hyu;Lee, Ki-Gang
    • Journal of the Korean Ceramic Society
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    • v.47 no.5
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    • pp.445-449
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    • 2010
  • The purpose of this study is to improve recycling rate of the waste glasses by investigating bloating mechanism. In this study, we use waste glass(W/G) and hard clay(H/C) as raw materials. The artificial lightweight aggregates were formed by plastic forming($\phi$=10 mm) and sintered by fast firing method at different temperatures(between 700 and $1250^{\circ}C$). The physical properties of the aggregates such as bulk specific gravity, adsorption and microstructure of surface and cross-section are investigated with the sintering temperature and rate of W/G-H/C contents. As the result of the bulk specific gravity graphs, we can found out the inflection point at content of W/G 60 wt%. From the microstructure images, we considered the artificial lightweight aggregates content of W/ G over 60wt% are distributed numerous micro-pores by organic oxidation without Black Core and the artificial lightweight aggregates of W/G below 60 wt% are distributed macro-pores with Black Core.

Reclamation of Inorganic wastes to Artificial Lightweight Aggregates

  • Chang, Hui-Lan;Liaw, Chin-Tson
    • Proceedings of the IEEK Conference
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    • 2001.10a
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    • pp.565-570
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    • 2001
  • Annually, Taiwan generates approximately 2 million tons of inorganic wastes in the form of sludge, fly ash and slug. To increase the added value of waste and maintain the increasingly insufficient supply of natural gravel, large public construction projects account for this large demand each year. future architectural trends are leading towards high-rise buildings. In light of the above, Center for Environmental, Safety and Health Technology Development, Industrial Technology Research Institute has developed the technology of manufacturing cold-bonding, sintering and bloating types of lightweight aggregates with a specific gravity ranging between 0.7~1.7, water absorption rate < 30%. The lightweight aggregate verified by physical property tests can be used as a substitute for the natural aggregate, which generally appears in replacing gravel in concrete, soundproofing and heat insulation materials. Doing so would not only moderate waste disposal problems, but also achieve the goal of resource recovery.

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A study on the characteristics of eological lightweight aggregates containing reject ash from the power plant (화력발전소 잔사회 입도에 따른 에코인공골재의 특성에 관한 연구)

  • Kim, Yoo-Taek;Ryu, Yu-Gwang
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.20 no.4
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    • pp.185-191
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    • 2010
  • To effectively utilize resources of reject ash and dredged soil, globular shape-formed artificial lightweight aggregate were manufactured in 8~10 mm size. Starting materials were changed various grading and composition, sintered at $1050{\sim}1250^{\circ}C$. The specific gravity, water absorptance of artificial lightweight aggregates were measured on the basis of the KS. In this study could make a prediction about application of bloating mechanism by ferrous materials and alkali/alkali-earth oxide at high temperature.

Bloating Mechanism for Artificial Light Weight Aggregate of Surface Modification with Coal ash

  • Lee, Ki Gang
    • Journal of the Korean Ceramic Society
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    • v.52 no.2
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    • pp.159-164
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    • 2015
  • We manufacture artificial lightweight aggregates (ALWAs) using bottom-ash as the primary raw material. We coat the ALWA surfaces with low-melting point materials in order to enable them to bloat, which is essential to reduce the bulk density of the aggregate. Then, we sinter the prepared aggregates at 1000, 1100, and $1200^{\circ}C$ using either the direct or two-step firing schedules. Finally, we evaluate the properties of the fired samples through analyzing their bulk density, water absorption, and microstructure. The surface-modified samples result in a reduction of their bulk density by $0.3{\sim}0.4g/cm^3$ regardless of the firing method used. Based on these results, we conclude that this approach could provide a viable method for the mass-production of ALWAs from industrial waste such as bottom-ash.

The Serverith Leverls and Patterns of Perimenstrual symptoms among Korean Women in relation to their Ages (여성의 연령과월경 전후기 증상 정도 및 유형에 관한 연구)

  • Park, Young-Joo
    • Women's Health Nursing
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    • v.5 no.2
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    • pp.162-175
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    • 1999
  • The study was intended to investigate and explore the preimenstrual symptoms, their severity levels, their patterns and the relationships of the age to those symptoms and patterns among Korean women. The data were collected from 844 women in one highschool, one Nursing college and one Korea National Open University in Seoul, from Nov, 1997 to Jun. 1998. The instruments were the Menstrual Symptoms Questionnaire developed by Chesney and the Center for Epidemiologic studies Depression scale developed by Radloff. the data were analyzed by descriptive statistics, ANOVA, Duncan's multiple comparison test, $X^2$-test, simple regression analysis and logistic regression analysis using pc-SAS program. The results were as follows ; 1. Korean women had more symptoms of abdominal bloating, fatigue, abdominal discomfort and backache in perimenstrual period. There Teenages had more symptoms of depression and uterine cramps in the day before or the first day of menstruation. Women in their twenties had more symptoms of abdominal pain or abdominal discomfort, backache, abdominal bloating and the sensitiveness /discomforts in the lower back, abdomen and inner part of thighs. women in their thirties had more symptoms of abdominal bloating, fatigue, tension and nervousness before the menstruation, abdominal discomfort and backpain in the first day of menstruation. Women in their forties had more symptoms of backache, breast discomforts, abdominal pain and discomforts. 2. The severity levels of the perimenstrual symptoms showed the highest score(mean=2.73) in twenties and the lowest score)mean=1.96) in forties The perimenstrual symptom patterns were prevailed the spasmodic menstrual symptoms in teenage and twenties and the congestive menstrual symptoms in thirties and forties. The age was a determinant of perimenstrual symptom patterns and the precipitative equation was log[p(age)/(1-p(age)]=2.7356-0.0982 age. 3. The relationship of the age to perimenstrual symptoms was vanished or lessened, controlling for parity as a test factor. this finding supports the notion that parity is an extraneous variable.

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Properties of artificial aggregates of coal bottom ash-dredged soil system added with waste glass (폐유리가 첨가된 석탄바닥재-준설토 계 인공골재의 특성)

  • Jo, Sinae;Kang, Seunggu
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.23 no.3
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    • pp.146-151
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    • 2013
  • In this study, the effect of addition of waste glassy slag produced from recycling of spent catalyst (denoted as waste glass hereafter) on the physical properties of artificial aggregates made of coal bottom ash and dredged soil (7 : 3 by weight base) was evaluated. Especially, the bloating behavior of artificial aggregates was analyzed by performing the relation study between the apparent density, water absorption and microstructure. The apparent density of artificial aggregates increased slightly with sintering temperature at $1050{\sim}1150^{\circ}C$, but decreased above $1150^{\circ}C$ showing bloating phenomenon. The bloating behavior of artificial aggregates was decreased so the apparent density increased with amount of waste glass added. Also, the water absorption of artificial aggregates decreased with sintering temperature. Above $1200^{\circ}C$, big fissure and much liquid were formed at the surface of artificial aggregates and these phenomena could be suppressed by increasing amount of waste glass added. The artificial aggregates fabricated in this study had an apparent density of 1.1~1.6 and water absorption of 8~22 % which meet KS requirements for the artificial lightweight aggregates.

Bloating mechanism of artificial lightweight aggregate with reject ash (잔사회를 이용한 인공경량골재의 발포기구)

  • Lee, Ki-Gang
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.22 no.3
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    • pp.158-163
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    • 2012
  • The purpose of this study is to improve recycling rate of the coal reject ash by investigating bloating mechanism for artificial lightweight aggregate of reject ash. In this study, we use reject ash (R/A) and dredged soil (D/S) as raw materials. The artificial lightweight aggregates were formed by plastic forming (${\phi}$ = 10 mm) and sintered by temperature raising method at different temperatures (between 1200 and $1275^{\circ}C$). The physical properties of the aggregates such as bulk specific gravity, adsorption and microstructure of surface and cross-section are investigated with the sintering temperature and rate of R/A-D/S contents. As the result of the bulk specific gravity graphs, we can found out the inflection point at content of R/A 80 wt.%. From the microstructure images, we considered the artificial lightweight aggregates content of R/A over 80 wt.% are distributed numerous uniform micro-pores by vitrification without Black Core and the artificial lightweight aggregates of R/A below 80wt.% are distributed macro-pores with Black Core.

A study on the Change of Conception about Soeumin Hwangdal(jaundice, (黃疸)) between ${\ulcorner}$Dongyi Soose Bowon${\lrcorner}$'GaboBon' and 'SinchukBon' ("동의수세보원(東醫壽世保元)" 갑오본(甲午本)과 신축본(辛丑本)을 통한 소음인(少陰人) 황달(黃疸)에 대한 고찰(考察))

  • Ham, Tong-Il;Hwang, Min-Woo;Kim, Sang-Bok;Lee, Soo-Kyung;Song, Il-Byung;Koh, Byung-Hee
    • Journal of Sasang Constitutional Medicine
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    • v.17 no.2
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    • pp.85-91
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    • 2005
  • 1. Objectives The Purpose of this article is to find out the change of Dong-Mu's concepts about Soeumin Hwangdal(jaundice;황달(黃疸)) 2. Methods This study Was researched as bibliographically with Dong-Mu's writings such as ${\ulcorner}$Dongyi Soose Bowon${\lrcorner}$ written in 1894('GaboBon'), ${\ulcorner}$Dongyi Soose Bowon${\lrcorner}$ published in 1901('Sinch ukBon') 3. Results and Conclusions I) The conception of Soewnin Hwangdal(jaundice, 황달(黃疸)) is a syndrome of indigestion, which needs releasing excessive through the method of decending the interior yin. 2) In the course of Taeum syndrome(태음병(太陰炳)), Soeuwnin Hangdal(jaundice황달(黃疸)) locate beetwen Miman (bloating, 비만(?滿)) and Bujong(edema, 부종(浮腫)) on the point of view of Healthy Energy. 3)In ?SinchukBon? , Soewnin interior disease is divided two syndromes. The one is the syndrome that has diarrhea as major symptom, and the another is the syndrome that has bloating as major symptom 4) In ?SinchukBon? , Dong-Mu suggested that diuresis is an important treatment of the syndrome which has bloating as major symptom.

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Bloating mechanism for coal ash with iron oxide (철분이 많이 함유된 석탄회의 발포거동)

  • Lee, Ki Gang
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.24 no.2
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    • pp.77-83
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    • 2014
  • The purpose of this study was to figure out the impacts of iron oxide types and dosages to bloating when producing artificial lightweight aggregates by utilization of recycled resources such as bottom-ash, reject-ash and dredgedsoil. In order to figure out chemical characteristics of raw materials, XRD and XRF analyses were performed. 50 wt% of dredged-soil, 15 wt% of bottom-ash and 35wt.% of reject-ash were mixed, then the amount of iron oxide was varied at 5 to 30 wt% with intervals of 5 wt% with $Fe_2O_3$ and $Fe_3O_4$ respectively. As molded aggregates were sintered by rapid sintering in intervals of $40^{\circ}C$ from $1060^{\circ}C$ to $1180^{\circ}C$, specific gravity and water absorption were measured. As a result, the artificial lightweight aggregate with iron oxide of 10~15 vol% showed the lowest specific gravity, and it was identified that the more iron oxide vol% increases, the more specific gravity increases because of liquid phase sintering.