• Membrane Journal
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• v.32 no.4
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• pp.227-234
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• 2022

Wastewater is released from leather, textile, paint, wood, or dye processing industries as well as petroleum refining industries. Wastewater from these industries contains water pollutant such as heavy metals and nitrogen compounds and has high chemical oxygen demand (COD). While there various filtering pollutants from wastewater for safe disposal, membrane-based technology is one of the most efficient methods for its high efficiency and low cost. Among various membranes, zeolite membranes gain spotlight for its cost-effectiveness and have undergone a lot of research. This review is focused on recent progress in zeolite membrane for wastewater treatment in following order: i) wastewater treatment, ii) microfiltration membrane, iii) hollow fiber membrane, and iv) ultrafiltration membrane.

• Corrosion Science and Technology
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• v.3 no.2
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• pp.59-66
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• 2004

In construction of new ships and large steel bridges in Korea, pre-construction primers (PCP), also known as shop primer, are routinely used and retained as an integral part of the protective coating system. Retention of PCP's can significantly reduce building schedule and cost. Retaining PCP through the so-called "sweep blasting" procedure eliminates or minimizes the necessity of a second blast operation, thus shortening overall schedule as well as reducing labor cost and hazardous waste disposal cost. This study evaluates the feasibility of retaining PCP as the part of primer for high performance protective coating systems applied to ships' hull, bottom and ballast tanks. Upon proving that the retention of the PCP is a viable option, the process of coating application can he improved significantly in terms of cost and working schedule of new ships and large steel bridges. Results indicate that use of the PCP via sweeping blasting in conjunction with standard high performance protective coating systems does not degrade the overall performance of the coating systems. At the same time, it is also highly recommended that the secondary surface preparation should consist of grit blasting of weld burnt and other damaged areas to SSPC SP-IO grade (Sa 2.5 Gr.), Near White Blast Cleaning with proper application and attention to detail.

• Ocean and Polar Research
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• v.38 no.3
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• pp.225-234
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• 2016

This project sought to conduct an economic feasibility study regarding the commercial production of bio-hydrogen by the marine hyperthermophilic archaeon, Thermococcus onnurineus NA1 using carbon monoxide-containing industrial off-gas. We carried out the economic evaluation of the bio-hydrogen production process using the raw material of steel mill by-product gas. The process parameter was as follows: $H_2$ production rate was 5.6 L/L/h; the conversion of carbon monoxide was 60.7%. This project established an evaluation criterion for about 10,000 tonne/year. Inflation factors were considered as 3%. The operating costs were recalculated based on prices in 2014. The total investment required for development was covered 30% by capital and 70% by a loan. The operation cost for the 0.5-year test and integration, and the cost for the first three months in the 50% production period were considered as the working capital in the cost estimation. The costs required for the rental of office space, facilities, and other related costs from the construction through to full-scale production periods were considered as continuing expenses. Materials, energy, waste disposal and other charges were considered as the operating cost of the development system. Depreciation, tax, maintenance and repair, insurance, labor, interest rate charges, general and administrative costs, lubrication and miscellaneous expenses were also calculated. The hydrogen price was set at US$ 4.15/kg for the economic evaluation. As a result, the process was considered to be economical with the payback period of 6.3 years, NPV of 18 billion Won and IRR of 26.7%.

• International Journal of Quality Innovation
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• v.6 no.3
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• pp.173-189
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• 2005

A life-cycle assessment (LCA) is based on the attention given to the environmental protection and concerning the possible impact while producing, making, and consuming products. It includes all environmental concerns and the potential impact of a product's life cycle from raw material procurement, manufacturing, usage, and disposal (that is, from cradle to grave). This study assesses the environmental impact of the ultra pure water process of semiconductor manufacturing by a life-cycle assessment in order to point out the heavy environmental impact process for industry when attempting a balanced point between production and environmental protection. The main purpose of this research is studying the development and application of this technology by setting the ultra pure water of semiconductor manufacturing as a target. We evaluate the environmental impact of the Precoat filter process and the Cation/Anion (C/A) filter process of an ultra pure water manufacturing process. The difference is filter material used produces different water quality and waste material, and has a significant, different environmental influence. Finally, we calculate the cost by engineering economics so as to analyze deeply the minimized environmental impact and suitable process that can be accepted by industry. The structure of this study is mainly combined with a life-cycle assessment by implementing analysis software, using SimaPro as a tool. We clearly understand the environmental impact of ultra pure water of semiconductor used and provide a promotion alternative to the heavy environmental impact items by calculating the environmental impact during a life cycle. At the same time, we specify the cost of reducing the environmental impact by a life-cycle cost analysis.

• Journal of the Korea Institute of Building Construction
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• v.18 no.5
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• pp.499-506
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• 2018

The number of demolition work is rapidly increasing because the middle- and high-rised buildings constructed over the rapid industrialization and urbanization have been deteriorated in social and structural aspects. However, theoretical approaches or studies related to the demolition cost prediction are still insufficient. Thus, this study derived and analyzed important factors affecting the fluctuation of the building demolition costs. 14 factors was derived through literature reviews and experts' interview, and the importance of each factor was analyzed to the each work(temporary work, structure demolition, and waste disposal) and the entire demolition work by using descriptive analysis. The survey results showed that the demolition costs was greatly influenced by environmental properties of the site. The results of this study can be used as a basis for estimating the approximate cost of the demolition work.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.394-399
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• 2009

Since some decades ago, there has been a concern for resource depletion and environmental pollution associated with building properties. In addressing such impact of the built environment, there is a recognition of the existence of alternative building materials, fuels for energy supply as well as technologies for waste handling and disposal. Nevertheless, for long time, the choice between such alternatives was dictated by factors such as differences in prices and aesthetic values. A new important dimension in discriminating between different options is the environmental dimension. This aspect is important since buildings are one of the spatially big new additions to the natural environment that consume a lot of materials and energy during their long lifetime. Thus, with the environmental dimension kept in mind, a existing cost estimation needs to be changed. A new cost assessment method, Life Cycle Cost, should calculate overall costs with dimensional factors: investment and utility costs as well as maintenance costs over the lifetime of the building. Aiming to give an overview of the present status of Building Life Cycle Assessment(LCA) tools as a basis for further research and development including economic performance, this paper describes and compares 3 different tools for Life Cycle Assessment(LCA) and economic analysis of the green buildings. This paper compared these approaches based on various aspects. These include economic analysis method, evaluation duration, data of results(index). Use of the comparison analysis is to produce a better picture and indicate profits and shortcomings for the tools as a group; thus providing important direction improvement of LCA tool as well as further research and development of this group of tools.

• Journal of the Korean Society for Railway
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• v.17 no.5
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• pp.373-380
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• 2014

With a view to the commercialization of the Korean automatic variable-gauge bogie in the Eurasia railway system, the aim of this research was to perform an economic analysis concerning the possible introduction and operation of this bogie at the present time. For this purpose, we compared the possible types of freight connection service for container transportation, transshipment and the gauge-adjustable system, estimating the total life-cycle cost (LCC) incurred by each system, depending on type and quantity, over the whole process of acquisition, operation, maintenance and disposal. Based on this, we presented a case-by case analysis. Furthermore, in estimating economic feasibility, we analyzed the cost-benefit ratio taking into account not only the objective LCC, but also the reduced time required for the gauge-change and customer convenience. After estimating the LCC and analyzing the cost-benefit ratio of the respective systems, we demonstrated the economic superiority of view of the gauge adjustable system.

• Nuclear Engineering and Technology
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• v.27 no.5
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• pp.721-729
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• 1995

The Korean optimal nuclear fuel cycle strategy from the year 2000 to 2030 is derived using linear programming. The fuel cycle cost, the cost uncertainty, and the natural uranium consumption are used as the criteria for the optimization. These objectives are compromised by fuzzy decision-making technique which maximizes the minimum degree of satisfaction among the three objectives. The options for the back-end fuel cycle are direct disposal, reprocessing, and DUPIC. The optimal fuel cycle strategy of Korea is to start reprocessing in around 2010 and increase its capacity with the maximum of 800 tHM in around 2025, and to star DUPIC processing in 2025. The cot uncertainty and the natural uranium consumption of the optimal fuel cycle strategy are reduced by 7.1％ and 6.1％, respectively, at the cost penalty of 5.4％ compared with the cost-only optimal solution.

• Journal of Environmental Impact Assessment
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• v.4 no.1
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• pp.9-15
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• 1995

For the purpose of saving the waste disposal cost a self-governing community on the whole reclamates the wetland and uses it as a landfill site. During the operation period of site, the environmental impact by the leachate is usually neglected. Therefore, to predict the environmental impact and dispersion of leachate, the wetland adjacent to the South Han River in Chungju is selected as a site of case study. The main content of this article is to apply the simulation model CONMIG to leachate transfer in the ground water and to derive the impact by the leachate. A kind of non-reacting conservative material, chloride ion is used as a tracer to quantify impacts by the leachate.

• Korean Management Science Review
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• v.13 no.2
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• pp.177-191
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• 1996

Quality is defined as several terms of fitness for use, conformance to requirements or specification, and loss of social effect. And the quality can be classified into design, production and service quality according to its formation of product (or servece). To be satisfactory product, the product must be controlled to maintain the specified level of quality at the whole life cycle of R&D step through disposal step. And the wrong design is one of the great source of cost. Therefore, the quality assurance on the R&D step is very important. This paper suggests a general procedure for the R&D quality assurance and discusses the methods for the reliable design. And a telecommunication equipment is considered as an applied example. Finally, it is discussed some subjects on the R&D quality assurance as further researches.