• 한국안전학회지
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• 제33권5호
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• pp.42-50
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• 2018

The Chemical Controls Act strictly regulates for the chemical companies to establish sufficient space between the liquid chemical tank and dike, but facilities already installed suffer from the space shortage between the tank and dike. Installing leakage preventing plates on the dike is considered as one of the economic solutions that can alleviate the space deficiency. However, there is no technical and reasonable criterion for the safety evaluation of the leakage preventing plate on the dike. In order to address this problem, we provide generalized and verified calculating equations that give maximum height and horizontal distance of leakage trajectories. Through the proposed equations, proper heights of the leakage preventing plates on the dike can be easily determined. In this study, new calculating methods are also developed to determine the impact force of the liquid to the leakage preventing plates. In addition, we performed the reactivity experiments between four corrosive liquid chemicals and two stainless steel materials that are candidate substances for the construction of the leakage preventing plate. The results of this study is expected to be applicable as a guideline in the design of safe dike and its leakage preventing plates.

• 한국산학기술학회논문지
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• 제20권1호
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• pp.464-469
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• 2019

본 논문에서는 화생방 방호시설에 사용되는 가스 차단밸브를 비롯한 각종 밸브 및 출입통제 챔버를 제어할 수 있는 원격 감시패널과 제어시스템을 개발하였다. 원격 감시패널은 화생방 통제실에 설치되는 메인 패널과 청정 기계실에 설치되는 보조 패널로 구성하였으며, 그 크기를 순수 제어용과 CCTV를 포함한 제어용으로 구분하여 개발하였다. 본 시스템은 방폭문 및 가스 차단문이 전시 및 평시에 발생할 수 있는 상황별 상태에 따라 원격 감시 및 제어가 가능하며, 평시모드와 전시모드로 구분하여 각 모드 작동시 추가적인 활성창을 통하여 제어 정보를 표시한다. 특히, 화생방 방호시설 내부의 각종 밸브 및 센서 그리고 각종 여과기의 동작상태를 주기적으로 센싱하여 각각의 기구 및 기기들의 정상동작 여부를 파악하며, 수리 및 교체가 필요할 경우 이를 원격으로 상황 근무자에게 경보함으로써 위급상황에서 각각의 기기들의 동작이상으로 인한 피해를 미연에 방지한다. 이를 통하여 화생방 상황 발생시 차단밸브 및 양압밸브의 상태에 따른 송풍기, 급기 및 배기 댐퍼의 작동, 비상 발전기 및 냉각수 펌프 등의 제어가 가능하여 재래식 무기 및 핵폭발에 의한 폭풍압의 급격한 유입으로 인한 피해를 예방할 수 있다.

• 한국위험물학회지
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• 제2권1호
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• pp.1-5
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• 2014

Acidic chemicals like sulfuric acid, nitric acid and hydrogen chloride take up 37% of the total chemical accidents which took place for the past 10 years. When an acidic chemical leak happens, fume is generated, diffusing into the air, which might cause serious damage to health of local residents and the environment. However, we have only little reference data for production and using of acidic chemicals. In this study, we investigated characteristics of production and using for acidic chemicals with high accident frequency. As a results, domestic chemical accidents were categorized according to chemical types and production, using, and handling characteristics of acidic chemicals were identified. Sulfuric acid was handled in the largest amount, followed in the order of hydrogen chloride, nitric acid, acrylic acid, and hydrogen fluoride. Sulfuric acid is used in the industry of manufacturing composite fertilizer and mainly used for manufacturing fertilizer. Hydrogen chloride is used in the industry of manufacturing basic chemicals for petrochemical family and mainly used for pH regulator. It is expected that this results could be used as preliminary data for making decisions on facilities required intensive management in order to prevent chemical accidents and prepare countermeasures against such accidents.

• 한국환경보건학회지
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• 제18권2호
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• pp.39-51
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• 1992

This study was carried out for 1 year between 1990 and 1991. The interviewers visited 513 households to evaluate the perception of the residents using the Simple Piped Water Supply (SPWS), and examined the pollution source surrounding 48 SPWS facilities and water quality by the chemical and microbiological method. The purpose of this study was to find out problems linked with SPWS and to investigate more efficient way of improvement in rural water supply. The results of the study are summarized as follows: 1) Approximately 44.0% of the sampled population have been served by simple piped water supply. 2) The drinking water was mostly taken from the springs in 8 sites and valley water in 40 sites. 3) Considering the type of distribution of the SPWS, there are 40 natural gravity systems and 8 pumping systems. 4) Out of the 180 SPWS in Chun Sung Area, 73.9% of the SPWS facilities %'ere used more than ten years. 5) 47.4% of the SPWS facilities are neighbored with pollution source. 6) 42.4% of the maintenance crews were not committed to their job but instead, the facilities were operated by some residents or community leaders who were personally concerned about quality of the facilities. 7) About 36.9% of the residents complaind that the amount of daily water supply is not adequate. 8) About 55.6% of the residents felt that the water quality is good for drinking water and therefore, But in contrast, the biochemical tests indicated that most of the SPWS met the drinking water quality standards. 9) Under the present water analysis system, The method of sampling and analysis are not effective, so that analysis system shoud be done by local health center.

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.69-75
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• 2014

Accurate analysis of fly ash particles is not trivial because of complex nature in physical and chemical properties. SPLITT fractionation (SF) was employed to fractionate the fly ash particles into subpopulations in large quantities. Then the SF-fractions were analyzed by the steric mode of sedimentation field-flow fractionation (Sd/StFFF) for size analysis. The SF-fractions were also analyzed by ICP-OES. The results showed that the fly ash is mainly composed of Fe, Ca, Mg and Mn. No particular trends were observed between the particle size and the concentrations of Fe, Ca, Mg, while Mn, Cu and Zn were in higher concentrations in smaller particles. Sample preparation procedures were established, where the fly ash particles were sieved to remove large contaminants, and then washed with acetone to remove organics on the surface of particles. The sample preparation and analysis methods developed in this study could be applied to other environmental particles.

• 한국가스학회지
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• 제10권1호
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• pp.13-18
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• 2006

산업재해를 방지하고 사고시에 적절한 대책을 마련하기 위해서는 각 위험설비와 위험물질로부터 발생할 수 있는 사고유형, 발생가능성 및 피해를 객관적인 단위로 평가하는 정략적 위험성평가가 수행되어야 하며, 이러한 정량적 평가를 수행하기 위해서는 신뢰도 데이터베이스가 필수적이다. 따라서, 본 연구에서는 사업장에서 설비 및 기기에 대한 신뢰도 데이터베이스를 구축하기 위해서 신뢰도 데이터 수집 및 분석체계구축, 자료 입력 및 분석 소프트웨어를 개발하여 구축된 자료를 토대로 정량적 위험성 평가에 활용할 수 있는 방법론을 제시하였다.

• Computers and Concrete
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• 제2권4호
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• pp.293-307
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• 2005

The development and the main features of an expert system for modeling the requirements of durable concrete in chemical exposure, called the Durable Concrete Advisor for Chemical Exposure (DCACE), are described. The system was developed to help improve the quality of concrete exposed to chemical environment by minimizing mistakes and deficiencies in selecting concrete constituents. Using Kappa-PC expert system shell, an object-oriented model was developed where the rule-based reasoning operates on or across objects. The American Concrete Institute manual of concrete practice was chosen as the main source of knowledge. Other textual sources were also consulted for knowledge acquisition. The major objectives of the research were acquisition and formalization of the relevant knowledge and building an expert system for making durable concrete for chemical exposure regarding sulfate attack, acid attack, seawater attack and carbonation. Similar to most expert systems, this system has explanation facilities, can be incrementally expanded, and has an easy to understand knowledge base. The performance of the system is demonstrated by an example session. The system is user-friendly and can be used as an educational tool.

• 한국안전학회지
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• 제31권1호
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• pp.111-117
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• 2016

Natural disasters can cause major accidents in chemical facilities where they can lead to the release of hazardous materials which in turn can result in fires, explosions or toxic dispersion. Technological disasters triggered by natural disasters are referred to as NaTech(Natural Disaster Triggered Technological Disaster). These trends increase the probability of catastrophic future disasters and the potential for mass human exposure to hazardous materials released during disasters. In the present study, we proposed some methods for effective disaster management by conducting case study of major NaTech. First, establishing information sharing system of chemical accident for stakeholders and improving disaster manuals and standards of central and local government and co-operation support system. Second, activating information service of emergency planning and community right to know. Third, improving the integrated chemical accident database including NaTech accidents.

• 대한안전경영과학회지
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• 제16권4호
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• pp.1-9
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• 2014

The occupational health and safety accidents were continuously increased during handling, usage and manufacturing the chemical materials according to increase of small and medium sized enterprises in domestic industries. These accidents mainly resulted from insufficient occupational health and safety management and deteriorative facilities and focused on corresponding operation to minimize the damage of accidents after occurrence. But, it was required that we grasped the occurrence causes of occupational health and safety risk in handling, usage and manufacturing the chemical materials and develop the adequate corresponding operation and system according to the possible occurrence of occupational health and safety risk. This study deals with the development of risk assessment model to derive the risk and important risk of occupational health and safety and then help to construct the self-controlled occupational health and safety system for small and medium sized enterprises handling the chemical materials.

• 상하수도학회지
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• 제24권5호
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• pp.537-548
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• 2010

Recently the Government has announced updated water quality standards for wastewater treatment effluent (become effective in 2012). That includes highly enforced regulations for T-P, BOD and COD, and a large budget, in particular for phosphorus removal, was set by the Ministry of environment. Chemical coagulation destabilizes colloidal particles so that particles grow to larger flocs, and solid particles are removed by solid-liquid separation. The efficiency of chemical coagulation depends on a various factors, including coagulant types and costs, construction and operation costs for the treatment facilities and so on. The proper selection should be based on the treatment efficiency of coagulants and underlying costs. The current research was to evaluate the treatment efficiencies of coagulants on a variety of wastewater influents and to develop saturation curves for several water quality parameters. Typical $Al_2(SO_4)_3$ and $FeCl_3$ were tested under a range of coagulant concentrations. The pollutant removal efficiencies of chemical treatment both for the $Al_2(SO_4)_3$ and $FeCl_3$ were especially high for T-P, followed by SS, BOD and COD. Correlation test also proved the highest relationship between SS and T-P.