• Journal of Biosystems Engineering
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• v.9 no.1
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• pp.62-70
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• 1984

가축배설물(家畜排泄物)의 콤포스트화(化) 작업(作業)의 공학적(工學的)인 국면(局面)은 축산(畜産) 경영(經營)의 축산물(畜産物) 생산성(生産性), 에너지 보전(保全), 공해방지(公害防止)와 분뇨처리(糞尿處理)의 노력(勞力) 절약(節約)에 긴밀(緊密)한 관계(關係)가 있다. 그러나 우리나라에 있어서 축산업(畜産業)의 사양(飼養) 규모(規模)와 두수(頭數)는 매년(每年) 증가(增加)하고 있는 경향(傾向)인바 전통적(傳統的)인 가축(家畜) 배설물(排泄物) 처리(處理) 및 재이용(再利用) 과정(科程)에서 발생(發生)되는 문제점(問題點)에 대(對)한 연구(硏究) 자료(資料)가 없고 특(特)히 콤포스트화(化) 작업(作業)이 원시적(原始的)이므로 개선(改善) 확립(確立)이 절실(切實)히 요구(要求)되는 실정(實定)이다. 본(本) 연구(硏究)의 목적(目的)은 가축(家畜) 분뇨(糞尿)의 콤포스트화(化) 작업(作業) 과정(科程)에서 공학적(工學的)인 제(諸) 문제점(問題點)을 조사(調査) 분석(分析)하여 현상(現狀)을 평가(評價)하고 개선(改善) 방안(方案)을 모색(摸索)하기 위한 기본자료(基本資料)를 제공(提供)하고져 수행(遂行)하였다. 이에 관한 조사(調査)와 분석(分析) 결과(結果)를 요약(要約)하면 다음과 같다. 1. 축산농가(畜産農家)의 가축(家畜) 배설물(排泄物) 처분(處分) 방법(方法)은 대부분(大部分)이 자연건조(自然乾燥), 퇴적(堆積), 혐기적(嫌氣的)인 고형(固形) 또는 액상(液狀) 퇴비화(堆肥化)에 의하여 실시(實施)되고 있었으며 가축분뇨(家畜糞尿)로 인(因)한 공해(公害)는 심각(深刻)하다는 것을 알 수 있었다. 2. 호기성(好氣性) 야적(野積) 콤포스트의 통기작업(通氣作業)은 트랙터에 부착(附着)되어진 전후(前後) 작동식(作動式) 로우더가 바람직하다. 3. 농축산(農畜産) 폐기물(廢棄物)의 콤포스트화(化) 작업(作業)은 축산농가(畜産農家)를 중심(中心)으로 한 콤포스트 센타에서 전체 농가(農家)가 지방(地方) 증진(增進)과 오염(汚染) 방지(防止)를 하기 위해 참여(參與)하여 완전(完全) 공동(共同) 이용(利用) 체계에 따라 일관성(一貫性)있게 수행(遂行)되어야 한다. 4. 호기성(好氣性) 야적(野積) 콤포스트 작업(作業)은 다른 방법(方法)에 비하여 운영비(運營費)가 적게 들어 영세적(零細的)인 축산업(畜産業)의 경우(境遇)에 가장 적당(適當)하고 공해(公害)를 방지(防止)함으로서 한국(韓國) 축산농가(畜産農家)의 콤포스트화(化) 시설(施設)로 전망(展望)이 밝다고 판단(判斷)된다.

• Journal of Radiation Protection and Research
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• v.20 no.4
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• pp.237-243
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• 1995

An estimate is made on the potential generation rate of H: from radiolysis of the Paraffin-wax encapsulant Proposed for the solidified liquid concentrate wasteform. The results show that the radiolytic Production of $H_2$ from paraffin-wax-encapsulated waste is dominated by the radiation energy released from $^{60}Co$. The radiolytic production of $H_2$ will proceed at an initial rate equivalent to aproximately $4.4{\times}10^2cm^3yr^1$ in 200 litre drums that are partly filled with 120 litres of encapsulated waste. The gas production rate will fall to a value of $7.2cm^3yr^1$ after 100 years. The lower flammable limit for $H_2$ in air will be reached in about 25 years and the lower explosive limit for $H_2$ in air would not be reached in 1000years. The timescale in which these safety-related limits are reached is strongly dependent on the level of filling of each waste drum. A reduction of the air space inside each drum would reduce the time required to reach the lower flammable limit.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.4
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• pp.129-137
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• 2000

In this study, biological treatment process of MWWT(Municipal wet-waste Treatment) has been developed through a moduling of the containerized closed ATAD(Auto thermal aerobic digestion) system & closed vertical dynamic acerator, which were used for food waste and cattle manure, respectively. Though biological process has several advantages such as low concentrations of heavy metals and salts, proper and stable C/N ratio and constant reaction rate against the process treating two wastes separately, it has a obstacles of salt concentration and much usage of bulking agent such as wood chip. After rapid oxidation in the boxed tower reactor for 5 days, the content of sewage sludge would be reduced 65% on around, might be mixed with the food waste that had been treated in the static closed reactor during 6 days and put in the secondary static reactor for curing. During composting process, the odor contained in the gas generated from the reactor was removed by passing it through a biofilter as well as the leachate was treated in the wastewater treatment facility. Consequently, it seemed to be possible to compost sewage sludge at mild and stable operating condition and at low cost through the biological ATAD process resulting in the production of organic compost satisfying the specifications regulated by itself.

• Economic and Environmental Geology
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• v.11 no.3
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• pp.89-98
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• 1978

Mineralogy, beneficiation, and processes of titanium ores are reviewed from petrographic viewpoints. The most important titanium minerals are ilmenite ($FeTiO_3$) and rutile ($TiO_2$). Ilmenite will play major role :for raw material, because rutile are rapidly diminishing. Thus, there is a need to develope a successful process for producing high grade Ti02 from ilmenite. Commercial, as well as R and D processes to treat more abundant ilmenite ores fall in three general classess: 1. Iron in ilmenite is partially or completely reduced and separated either physically or chemically. 2. Iron is reduced to ferrous state and chemically leached away from the titanium. 3. Ore is treated to make chlorides either selectively or with subsequent separation and purification of $TiC_4$. Routes and efficiencies of these process technologies are primarily influenced by the particular ore deposit to be mined and secondly by environmental considerations. One deposit parameters which influence ilmenite process technologies are: 1. Complexity of microtextures of ilmenite intergrown with Fe-oxide minerals. 2. Composition of concentrates; ilmenites contain minor amounts of substituted Mg, Mn, and V. These elements plus iron and gangue minerals can cause difficulties to complete reactions, substantial acid consumption, difficulties of removing waste solids, and waste disposal problems. Major contributions to be made by petrologists for process optimization are: characterization and interpretation of compositional and physical changes of raw materials and solids derived from process streams. These informations can play significant role in selecting and improving process steps for titania production.

• Journal of the Mineralogical Society of Korea
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• v.23 no.4
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• pp.347-356
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• 2010

Bauxite is a main raw material for the production of alumina and aluminum hydroxide in the processing plant of KC company. It is a NORM (Naturally Occurring Radioactive Materials), and its waste, red mud, is a TENORM (Technologically Enhanced Naturally Occurring Radioactive Materials). The purpose of the geochemical and mineralogical investigations of the bedrock and soils in and around the plant, a large NORM source, was to provide basic data for measuring the radiation dose and protecting from radioactive hazards. Soils were mixtures of minerals derived from the country rock (quartz, feldspar, mica, kaolin, gibbsite, and sepiolite) and bauxite (hematite, boehmite, and calcite) of open-air storage. Average U and Th contents of the soil samples were 4.7 ppm and 23 ppm, respectively, indicating somewhat Th anomaly. The average concentrations of radionuclides are $^{40}K$ 100~1,433 Bq/kg, $^{226}Ra$ anomaly in the red mud open-air storage. Soil external hazard indices range from 0.10 to 1.66 with an average of 0.63. Although most of the indices are below 1.0 that is a regulation value, those of 4 samples of total 41 soil samples exceed 1.0, requiring further detailed investigation.

• The Korean Journal of Mycology
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• v.22 no.3
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• pp.266-275
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• 1994

Brewer's yeast extract can be used as a good substrate for the culture of Lentinula edodes Mycelia(LEM). We found that it was better to filter the extract through three kinds of sieves and then to heat for hydrolysis and concentration at $90^{\circ}C$ prior to use. Also the maximum condition for the growth of LEM was investigated. We found that addition of inorganic salts such as calcium enhanced the growth of LEM. On the other hand, addition of carbon and nitrogen sources to the medium did not affect, and even inhibited under certain conditions, the growth of LEM. The maximum temperature for the growth of LEM was around $25^{\circ}C$. Also, it grows better when agitated by shaking at 100 rpm for airration. The appropriate concentration of the extract to use was 10%. Under these conditions, LEM could reach to the confluency after cultivation of 12 days. Our extract formula seems better than other available media for LEM growth, producing higher crude protein content and better taste.

• Applied Chemistry for Engineering
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• v.35 no.1
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• pp.54-60
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• 2024

The present study was aimed to evaluate the removal of the trace pollutants (heavy metals and microplastics) in the sewage treatment plant by using the jellyfish Extract at Immunity reaction (JEI) of Aurelia coerulea. The experiment was conducted on two different scales: the lab scale using a Jar-tester and the Pilot system scale equipped with two newly developed devices in the laboratory, the active tube connection mixed system and the concentration integrated separation device. Compared to anionic polymers currently used in the field, JEI showed similar or higher efficiency to remove the trace pollutants. When JEI was added to the effluent through the Pilot system, the combination of JEI and the trace pollutants was maximized through two mixing processes, and as a result, the removal rate of the trace pollutants was greatly improved. Based on these results, we propose the present technology as an alternative to removing trace pollutants that can reduce ecosystem risk and minimize the generation of inorganic waste, away from the existing method.

• Economic and Environmental Geology
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• v.44 no.1
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• pp.37-48
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• 2011

Some industrial minerals used in domestic industries such as monazite, apatite, bauxite, and ilmenite belong to NORM (Naturally Occurring Radioactive Materials) because they show a high radioactivity. Products, semi-products, wastes, and by-products which show higher radioactivity than NORM belong to TENORM (Technologically Enhanced Naturally Occurring Radioactive Materials). Apatite used for manufacturing phosphate fertilizer in Namhae Chemical company belongs to NORM, and its by-product, phospo-gypsum, belongs to TENORM. A geological investigation is needed for the future environmental impact assessment of the Namhae Chemical company's site. According to survey results of the Namhae Chemical company's site, soil mineral composition indicated the mixture of minerals derived from the country rock (quartz, feldspar, mica, $l4{\AA}$ mineral, kaolin and amphibole) and minerals from the gypsum open-air storage yard (gypsum and apatite). Soil samples showed average content of U 4.6 ppm and Th 10 ppm, which are similar to average crustal abundances. They also show average contents of $^{40}K$ 191-1,166 Bq/kg, $^{226}Ra$ 15.6-710 Bq/kg, and $^{232}Th$ 17.4-72.7 Bq/kg, which indicate moderate levels of radio nuclide. But $^{226}Ra$ anomaly in the gypsum open storage yard is clearly confirmed and $^{232}Th$ anomaly is also confirmed in the east road side of the factory and nearby mountain areas. Soil external hazard indices ranged 0.24-2.01 with the average 0.54. Although most external hazard indices were lower than 1, which means radiation hazard index to be negligible, 5 samples out of total 40 samples showed higher values than 1, and further detailed investigation is needed.