• Culinary science and hospitality research
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• v.11 no.3 s.26
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• pp.121-137
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• 2005

Today's rapid industrialization and population concentration in cities lead to a vast economic growth, and consequently, people's increased desire of spending demands abundant and diverse food. As a result in Korea, annual food waste is 4.1 million tons (24.6% of household waste) and daily food waste amount to 11,397 tons which is equivalent to 1,400 loads of 8-ton truck. It is best to recycle toed waste as manure, forage, and fuel than reclamation but separate collection of food waste is very difficult by reason of water content. So only a little portion of food waste from large-scaled restaurants and cafeterias that handle food waste relatively well. requirement for recycling food wastes into forage and manure needless to say, reduction activity is best way. Therefore, large-scaled restaurants and cafeterias need to seek plans to minimize food resource waste thus reducing the cost and waste processing cost by implementing appropriate reduction program.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.3
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• pp.85-90
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• 2006

The purpose of this research is to design an imitation boiler similar to the waste heat boiler installed on a plasma melting furnace in order to acquire a capability of a thermal design as to the circulation of heat and the discharge of noxious gas inside a boiler and to improve the efficiency of a waste heat boiler using the CFD (Computation Fluid Dynamics) program. The position of corrosion and the generation of a clinker inside a boiler due to temperature changes, combustion gas flows, and corrosive gases inside a boiler are examined to design the structure of an efficient boiler and recycle energy. As a result of this research, the boiler installed on a plasma melting furnace met the conditions of design by cooling the combustion gases discharged after the second combustion from an exhaust port, originally at 1,200 degrees Celsius, down to around 450 degrees Celsius. On the other hand, the circulation of corrosive gases (SOx and HCL) may lead to the generation of corrosion or a clinker in the upper and lower parts of an exhaust port more easily than any other parts of a boiler. Accordingly, the corrosion on the inside and outside walls of a boiler may result in a shortened lifespan of a boiler and an inability to recycle waste heat in an efficient manner. A prevention against corrosion at high and low temperatures needs to be considered in detail.

• Computers and Concrete
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• v.26 no.4
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• pp.327-342
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• 2020

The objective of this study is to manufacture environmentally-friendly synthetic lightweight aggregates that may be used in the structural lightweight concrete production. The cold-bonding pelletization process has been used in the agglomeration of the pozzolanic materials to achieve these synthetic lightweight aggregates. In this context, it was aimed to recycle the waste fly ash by employing it in the manufacturing process as the major cementitious component. According to the well-known facts reported in the literature, it is stated that the main disadvantage of the synthetic lightweight aggregate produced by applying the cold-bonding pelletization technique to the pozzolanic materials is that it has a lower strength in comparison with the natural aggregate. Therefore, in this study, the metakaolin made of high purity kaolin and calcined kaolin obtained from impure kaolin have been employed at particular contents in the synthetic lightweight aggregate manufacturing as a cementitious material to enhance the particle crushing strength. Additionally, to propose a curing condition for practical attempts, different curing conditions were designated and their influences on the characteristics of the synthetic lightweight aggregates were investigated. Three substantial features of the aggregates, specific gravity, water absorption capacity, and particle crushing strength, were measured at the end of 28-day adopted curing conditions. Observed that the incorporation of thermally treated kaolin significantly influenced the crushing strength and water absorption of the aggregates. The statistical evaluation indicated that the investigated properties of the synthetic lightweight aggregate were affected by the thermally treated kaolin content more than the kaoline type and curing regime. Utilizing the thermally treated kaolin in the synthetic aggregate manufacturing lead to a more than 40% increase in the crushing strength of the pellets in all curing regimes. Moreover, two numerical formulations having high estimation capacity have been developed to predict the crushing strength of such types of aggregates by using soft-computing techniques: gene expression programming and artificial neural networks. The R-squared values, indicating the estimation performance of the models, of approximately 0.97 and 0.98 were achieved for the numerical formulations generated by using gene expression programming and artificial neural networks techniques, respectively.

• Journal of Environmental Policy
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• v.13 no.2
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• pp.65-98
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• 2014

Plastics of the marine environment are broken gradually down into smaller particles by chemical weathering, called "microplastic". Microplastics absorb organic pollutants that are persistent bioaccumulative substances. If marine animals ingested microplastic added to contaminant, it will lead to a bioaccumation through the food web. It eventually destroy health of marine environment and is harmful to marine top predators including humans. Also, Microplastics can impact marine animals by leaching the endocrine disruptor in microplastic itself as well as playing an adsorbent role of organic pollutants. Persistent and bioaccumulative substances in Korea have been regulated in terms of chemical risk but existing regulations largely have been limited in land-based source management of microplastic. Thus, the harmful impact will be increased whether the microplastics absorbed contaminants. To prevent risk of persistent bioaccumulative substances, this study suggests the following: (1) the strict management of microplastic by designating the hazardous substances, (2) expand the use of biodegradable plastic, (3) the effort for reuse and recycle, (4) the expand of microplastic clean-up programs.

• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.27-32
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• 1997

Continual monitoring of abnormal operating conditions i a key issue in maintaining high product quality and safe operation, since the undetected process abnormality may lead to the undesirable operations, finally producing low quality products, or breakdown of equipment. The statistical projection method recently highlighted has the advantage of easily building reference model with the historical measurement data in the statistically in-control state and not requiring any detailed mathematical model or knowledge-base of process. As the complexity of process increases, however, we have more measurement variables and recycle streams. This situation may not only result in the frequent occurrence of process Perturbation, but make it difficult to pinpoint trouble-making causes or at most assignable source unit due to the confusing candidates. Consequently, an ad hoc skill to monitor and diagnose in plat-wide scale is needed. In this paper, we propose a hierarchical plant-wide monitoring methodology based on hierarchical decomposition and principal component analysis for handling the complexity and interactions among process units. This have the effect of preventing special events in a specific sub-block from propagating to other sub-blocks or at least delaying the transfer of undesired state, and so make it possible to quickly detect and diagnose the process malfunctions. To prove the performance of the proposed methodology, we simulate the Tennessee Eastman benchmark process which is operated continuously with 41 measurement variables of five major units. Simulation results have shown that the proposed methodology offers a fast and reliable monitoring and diagnosis for a large scale chemical plant.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.163-170
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• 2019

In recent years, various types of industrial wastes are rapidly increasing with the development of high-tech industries. Specially, high-density waste glass of CRT TV containing heavy metals are buried or disposed of due to reprocessing costs and environmental pollution problems. Thus, more basic research is needed to recycle waste such as CRT waste glass such. In this study, the fundamental properties and radiation shielding performance of mortar specimens substituted CRT waste glass as a fine aggregate were analyzed and their application to shielding materials was evaluated. According to the results, the bulk density of mortar specimen replaced with CRT waste glass was increased and the compressive strength and flexural strength were decreased. Meanwhile, the CRT waste glass substitute specimen containing a large amount of lead component showed a higher shielding performance than the general mortar specimen. Especially, the linear attenuation coefficient of CRT waste glass in $122KeV{\cdot}^{57}Co$ of the low energy field was 2.5 times higher than that of normal specimen.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.2
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• pp.52-69
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• 2016

The fishing port was once the foothold of production as well as the stronghold of communities but with the declining of the fishing industry, ports became abandoned space. Jeju Special Self-Governing Province has continued its effort to vitalize marine tourism since 2010. Shinyang Port in particular is designated as a Prearranged Marina Port Development Zone, and planning for the Jeju Ocean Marina City project is underway. Nevertheless, fishing port remodeling projects implemented on Jeju so far have focused only on civil engineering such as renovating old facilities. In addition, most Marina Port Development Projects have been irrelevant to local communities. Leading projects by the local government mostly suffer from a lack of funding, which results in the renovation of old facilities and improper maintenance, while private sector investment projects do not lead to benefit sharing with the community. Shinyang Port, also renovated in 2008, ended up with outer breakwater extension construction that neither solved the fundamental problem of the site nor gave benefits to residents. To arrange a way to solve problems for civil engineering focused development project, improper maintenance, and benefit sharing with community, first, this study proposes a development plan that connects with the outlying areas near the ports. The plan reflects existing topography, Jeju traditional stonewalls, narrow paths on the master plan and programs by reading the regional context. In this way, this paper suggests a space development plan reflecting the local landscape and characteristic factors. Second, it satisfies various needs by using existing and new Marine Tourism Resources. Third, it examines sustainable operation and management measures through residents' participation. The proposal is significant in two key ways: it is a fresh attempt at connecting the fishing port with its outlying areas from a landscape perspective; and it considers environmental, social, economic issues, and suggests participation for local communities. Thus, the model can be used in future fishing-port remodeling plans for revitalizing unused space, including invaluable traditional landscapes, and for boosting the marine-leisure industry.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.19-29
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• 1994

A large volume of paper mill sludge(PMS) is produced every day from paper industries after treatments of waste water and it costs too much to dispose of the sludge. Since PMS consists mostly of biodegradable organic matter, cellulose, it is desirable to recycle it by proper treatments such as composting. In this study, experiments were conducted using a small scale reactor(12l) to establish optimum conditions for efficient composting of PMS of which initial pH, C/N ratio, and moisture content were 7.1, 28~30, and 60~65%, respectively. No heavy metals such as mercury, cadmimum, and lead were not detected in the PMS. Various levels of forced aeration, 1 minute aeration per every 30, 60, 120, 240, and 480 minutes were applied and 1 minute aeration per 60 and 120 minutes found to be proper for composting of 8l PMS in this system. Relationship between $CO_2$ production and temperatures was positively correlated with r> 0.82 suggesting that the normal decomposition of PMS by microorganisms occurred. However, under the condition of aeration interval over than 240 minutes, a negative relationship between two parameters was found indicating the occurrence of abnormal(maybe anaerobic) degradation. The amount of added nitrogen also affected composting of PMS resulting in the increase of $CO_2$ production and temperature. Semi-field tests using 100kg PMS in a static pile sysem showed that PMS could be composted efficiently under optimal environmental conditions. The parameters determining efficiency of composting such as C/N ratio, aeration, moisture content, and pH need to be monitored.