• Resources Recycling
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• v.26 no.3
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• pp.39-46
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• 2017

AlN powder was prepared by carbon reduction and subsequent nitridation method through lab- scale experiments. AlN powder was synthesized using the mixture of high purity $Al_2O_3$ powder and carbon black at $1,600{\sim}1,700^{\circ}C$ for 0.5~6 hours under nitrogen atmosphere (flow rate of nitrogen gas: $4.7{\times}10^{-6}{\sim}20{\times}10^{-6}m^3/sec$) with variation of charged height of the mixture powder. Experimental results showed that size of the synthesized particles grows with increasing of temperature. The reaction activation energy was calculated as 382 kJ/mol at the temperature range, and it was considered that chemical reaction is the rate determining step. Content of oxygen and nitrogen of the prpared samples were 0.71~0.96 wt% and 30.7~35.1 wt%. The results was similar with those of the commercial AlN product.

• Clean Technology
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• v.2 no.2
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• pp.51-59
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• 1996

Billions of tons of industrial waste are generated annually in industrialized countries. Managing and legally disposing of these wastes costs tens to hundreds of billions of dollars each year, and these costs have been increasing rapidly. The escalation is likely to continue as emission standards become even more stringent around the world. In the face of these rapidly rising costs and rapidly increasing performance standards, traditional end-of-pipe approaches to waste management have become less attractive. The most economical waste management alternatives in many cases have become recycling of the waste or the redesign of chemical processes and products so that wastes are prevented or put to productive use. These strategies of recycling or reducing waste at the source have collectively come to be known as pollution prevention. The engineering challenges associated with pollution prevention are substantial. This presentation will categorize the challenges in three levels. At the most macroscopic level, the flow of materials in our industrial economy, from natural resource extraction to consumer product disposal, can be redesigned. Currently, most of our raw materials are virgin natural resources that are used once, then discarded. Studies in what has come to be called industrial ecology examine the material efficiency of large-scale industrial systems and attempt to improve that efficiency. A second level of engineering challenges is found at the scale of individual industrial facilities, where chemical processes and products can be redesigned so that waste is reduced. Finally, on a molecular level, chemical synthesis pathways, combustion reaction pathways, and other material fabrication procedures can be redesigned to reduce emissions of pollution and unwanted by-products. All of these design activities, shown in Figure 1, have the potential to prevent pollution. All involve the tools of engineering, and in particular, chemical engineering.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.2
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• pp.179-185
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• 2014

A use of Asbestos onboard was banned by the provisions of SOLAS since 1 January 2011. And this provision was also implemented by the Rule for Ship's Facilities in Korea. However, these provisions were only declaration and there were no detailed measures for detect, removal and confirmation. In this study, by reviewing the Ship Recycling Convention, IMO circulars and Asbestos Safe Management Act, the following strategies for each concerned parties were proposed. The administration and class society should establish the provisions for appointment of subject vessel which to be inspected for asbestos, criteria for asbestos management and appointment of handling expert. The shipbuilder and equipment manufacturer should make written confirmation that asbestos was not used in their product. And shipowner and ship manager should establish procedure for onboard control of asbestos in the ship's safe management system.

• Korean Institute of Interior Design Journal
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• v.21 no.3
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• pp.194-202
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• 2012

The purpose of this study is to extract environment-friendly planning elements to apply in Korea by putting together and reclassifying four foreign environment-friendly certification systems related to regeneration spaces - LEED in USA, CASBEE in Japan, BREEAM in England and BEAM in Hong Kong - and analyze and evaluate domestic and foreign spaces which were certified as Environment-friendly spaces in order to offer plan guidelines to raise awareness of the importance of environment-friendly elements in regeneration spaces and to encourage them. The concept and the characteristics of green building were studied through documentary survey. In addition, green certification system of the present domestic new spaces and foreign regeneration spaces was studied and assessment tools for indoor regenerated spaces-related green certification system were developed. With checklists which are developed in this study, level of going green of foreign spaces certified environment-friendly was assessed. Based on the results of this study, conclusions are as follows. As a result of case research of spaces-certified green of Hong-Kong's existing buildings with a developed checklist, application of general assessment part was all alike, but that of detailed assessment part was different. However, Hong Kong showed superiority in lighting energy saving, separate collection of recyclable domestic waste, recycling by-product and management. In addition, Hong Kong applied eco-friendly planning elements maintaining buildings in their condition as possible as it could with management, use of green program, replacement with high efficiency lighting, monitoring system, installation of recycling bins and energy saving by attaching reflective film.

• Resources Recycling
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• v.21 no.6
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• pp.23-31
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• 2012

Removal work about weeds that grow naturally on road and industrial complex is attaining ordinary times but is suffering difficulty in weeding work by strong self-generation power. In the meantime, going side by side with these manual processing and weeding work through construction of weed-proof seat is attaining, but economic performance, limitation of application region and withdrawal processing problem are being blamed for shortcoming. The scope of this study is about the manufacture of weed-proof mortar using eco-friendly industrial byproducts characterized by an economic and simplicity for not limited to loss of function as a product recovered after treatment. After the carried out the various experiments and actual construction for the selection of mixing materials and derivation of appropriate mix, through the comparison and analysis of results, it was investigated the research results of weed-proof mortar for fundamental development.

• Resources Recycling
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• v.19 no.1
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• pp.13-20
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• 2010

Much energy is consumed up when making a concrete. And especially, because lots of $CO_2$ is discharged for combination material, cement, we are making efforts in order to get lid of this negative thought. Recently, much interest is given to manufacturing eco concrete which is environment friendly and its' application. We should study manufacturing of the concrete whose environment friendly performance should be improved as consistent development concept in order for various approaches to be settled down our country such as lowering of environmental load, utilization of industry wastes and improvement of environment related performance. This study inquired into utilization possibility through from various tests results after manufacturing eco type mixed concrete whose purpose is to lower environmental load in which cement and aggregates can be replaced with metakaolin which is natural material and copper slag which is industry by product.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.4
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• pp.333-340
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• 2019

Red mud is an industrial by-product produced during the manufacturing aluminum hydroxide (Al(OH)3) and aluminum oxide(Al2O3) from Bauxite ores. In Korea, aproximately 2 tons of red mud in a sludge form with 50% moisture content is produced when 1ton of Al2O3 is produced through the Bayer process. Neutralization of red mud will help to reduce the environmental impact caused due to its storage and also lessen significantly the ongoing management of the deposits after closure. It will also open opportunities for re-use of the residue which to date have been prevented because of the high pH. Moreover, attention to liquefied red mud(LRM) that does not require heating and grinding process for recycling is needed. In this paper, characteristics of compressive strength for cement paste with content of LRM neutralized by nitric acid and sulfuric acid. The results showed that compressive strength of cement paste with neutralized LRM is higher than that of cement paste with LRM.

• Resources Recycling
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• v.14 no.1
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• pp.33-38
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• 2005

Worldwide magnesium market has been considerably growing recently due to adoption as light materials for automobile engines and electronic devices such as mobile phones. In this study, it is to prepare magnesium oxide, which is the first-step product in smelting of magnesium from the ore, using magnesite of Yongyanag mines in North Korea as raw ores. MgO grade of the magnesite was about 45 wt%, and SiO$_2$, CaO, Al$_2O_3$ and Fe$_2O_3$ were contained as impurities. The sample ore was crushed, classified and thermally analyzed to determine its calcination temperature. The sample of 45-75 ${\mu}m$ size was calcined at 600-900$^{\circ}C$, and effect of temperature on calcination and change of the particle shape was investigated. Optimum temperature of the calcination was about 750$^{\circ}C$, and 30 minutes was sufficient to obtain over 99% conversion. The purity of the calcined MgO was about 95 wt%.

• Resources Recycling
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• v.25 no.5
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• pp.57-63
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• 2016

This study were carried out sulfation roasting and selective leaching test for the effective recovery of copper component in concentrate obtained by froth floatation of Autrallian low grade copper ore. The optimum conditions of sulfation roasting were temp. $450^{\circ}C$, $Na_2SO_4$ 2 mole ratio and time 1.5 h, and then selective leaching were room temperature and $H_2O$ or 1M $H_2SO_4$ solutions. Leaching efficiency of optimum sulfation product were 90 wt.% of copper, 20 wt.% of iron and 15wt.% of nickel elements. In this results, it was possible to selective decomposition leaching of the copper component under optimum conditions in this research.

• Resources Recycling
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• v.19 no.6
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• pp.86-92
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• 2010

In the many kind of construct-material, the concrete which has the high-strength and a durability is sufficient to use with structure-material. but the color of concrete is very monotony, so generally concrete isn't used the out surface. although color concrete is a method of expressing surface, the combination of pigment and cement cause many physical problem such as efflorescence phenomenon, strength degradation and so on. In this study, It attempt to develop the black mortar using the industrial granulated blast furnace slag and to evaluate basic physical properties compare with general color concrete to solve the color concrete problem. The result of experiment showed that the flow dropped mixing of pigment. but flow increased in proportion to the mixing rate in occasion of mortar that mix granulated blast furnace sla and black mortar which was made granulated blast furnace slag has more visible black color than any mortar.