• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.287-293
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• 2012

This paper has dealt with the probability of oyster shell desiccant cooling system driven by renewable energy of photo-voltaic effect. For this, fundamental experiments have been carried out focusing on the observation of dehumidifying effect of oyster shell and peltier elements used for air conditioning system. From this study, it is found that oyster shell has sufficient probability for using as a desiccant in air-conditioning system. Moreover, the heat releasing device(peltier element) can be used with direct current from PV cells so the system can be operated with high efficiency. As a result, the absolute humidity in a test chamber was reasonably controlled by oyster shell and peltier elements. Also the photo-voltaic energy from sun was enough for running power of this system.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.317-326
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• 2021

In this study, we investigated for Bio-EPDM foam with oyster shell surface modified earth coupling agent. Experiments were carried out to confirm the bio-EPDM/Oyster shell foam applying content of earth coupling agent. The cure characterization were evaluated by measuring the mooney viscosity and oscillating disc rheometer (ODR). Mechanical properties such as hardness, tensile strength, elogation at break and tear strength were measured, and changes of mechanical properties were also evaluated after immersion in NaCl solution. In addition degree of volume change was measured after immersing the Bio-EPDM foam in NaCl solution and the low-temperature permanent compression set was evaluated at 4℃. To evaluate the low-temperature characteristics of Bio-EPDM/Oyster shell, the glass transition temperature was measured using Differential Scanning Calorimeter (DSC). As a result as the content of the earth coupling agent increased up to 3phr, the crosslinking density and mooney viscosity increased, and the mechanical properties and low-temperature permanent compression set improved, but from 4phr, it was rather decreased. The change in the glass transition temperature was insignificant, and the foam cell appeared to be uniform when the earth coupling agent was applied.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.197-203
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• 2009

This study was conducted to investigate the food components of cooking drips from shell oysters steamed under various retort pressures. Among the drips from shell oyster steamed under different retort pressures (1.0, 2.0, 2.5, 3.0, 3.5, 4.0 and 4.5 kg/$cm^2$) the oyster drip obtained at the 4.5 kg/$cm^2$ of retort pressure had the highest degree of brix, yield, crude protein, glycogen and trichloroacetic acid soluble-N contents, while its salinity was the lowest. In the results of food safety test, the presence of E. coli (18 MPN/100 g>) and viable cell (30 CFU/g>) in the oyster drip was in acceptable level as a food-stuff. However, the sensory evaluation such as color, flavor and taste, total amino acid and free amino acid contents of cooking drip from shell oyster steamed at 4.5 kg/$cm^2$ were inferior to those of oyster wash water. Differences in the major amino acids of total amino acid and free amino acid between oyster cooking drip and oyster wash water were also found. The results suggested that the effective use methods of oyster cooking drip should be investigated.

• Journal of Korean Society on Water Environment
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• v.32 no.5
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• pp.458-464
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• 2016

This study evaluated the dewatering efficiency of inorganic dehydrating agents that contain oyster shells. A filter press dehydrator was used for this study. The experiments were performed by the single injection of calcium-based chemicals, the single injection of oyster shells, and the mixed injection of oyster shells and calcium-based chemicals. The moisture content of the dewatered cake generated after dehydration confirmed that the best dewatering efficiency was found at the mixing ratios of CaCO₃ to sludge, oyster shell to sludge, and inorganic dehydrating agent to sludge of 3:1, 10:1, and 1.5:2.5:1, respectively. The moisture contents exhibited less than 58% when the injection mixing ratio of inorganic dehydrating agent to sludge was 1.5:2.5:1. From EPS, SEM, and EDX analysis, it was found that the calcium adsorbed on the sludge surface could reduce extracellular polymeric substances (EPSs) and enhanced the dewaterbility. Based on the above results, it is considered possible to apply inorganic dehydrating agents containing recycled oyster shells in sludge dewatering in order to reduce sludge.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.4
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• pp.229-240
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• 2022

Purpose : In this study, using Oyster Shell Thermal Therapy for metabolic diseases, we analyzed the effect of immune and inflammation-related variables and respiratory health-related variables of test subjects to verify the effect of improving respiratory health. Methods : In this study, 26 patients with metabolic diseases were divided into an experimental group (N=13) and a control group (N=13). After Oyster Shell Thermal Therapy (four weeks/three times a week/1 hour per time), metabolic disease-related variables and immune and respiratory health-related variables were measured and compared between the two groups. The conclusion of this study is as follows: Results : After the four-week Oyster Shell Thermal Therapy, in terms of changes in the metabolic disease-related variables, the control group exhibited a higher increase in TC and LDL-C levels than the experimental group. In the case of glucose, the experimental group showed a decrease after the experiment (p<.05). After the four-week thermotherapy, a statistically significant interactive effect occurred in natural killer (NK) cells among the immune-related variables. According to the results of a post-experimental analysis, the control group showed a higher decrease in NK cells than the experimental group (p<.05). After the 4-weeks thermotherapy, the experimental group showed a greater increase in maximum oxygen intake of the respiratory health-related variables than the control group. Conclusion : Based on a comprehensive review of the study results, the subjects who underwent the four-week Oyster Shell Thermal Therapy exhibited positive physical changes in metabolic disease-related variables as well as immune and respiratory health-related variables, which demonstrates the effectiveness of Oyster Shell Thermal Therapy on immune and respiratory health. Accordingly, it is recommended to conduct long-term Oyster Shell Thermal Therapy with various models in terms of the size and shape.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.527-532
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• 2010

Soil-cement has been broadly used for eco friendly pavement, slope protection and soft soil improvement since it used for the increase of soil strength with cement. Recently, additional agents are mixed with existing soil-cement so as to improve specific properties or functions such as strength, color and permeability of it. This study aims at figuring out the physical and mechanical properties of a soil-cement mixed with crashed oyster shell and loess. The study is specially focused on the applicability of oyster shell as an alternative material for sands. To have his objective achieved a series of uniaxial compression tests were conducted. As a result, it appears that usage of oyster shell may have effect on strength improvement of mixed soils.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.11a
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• pp.72-84
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• 2001

In order to utilize mass of oyster shells for a partial substitute material for reclamation, we investigate the shear characteristics of dredged sluge mixed with oyster shells. the apparent modulus of elasticity of the this mixture are obtained from the triaxial compression tests and is utilized to characterize the apparent modulus of elastic of the oyster shells by carrying out some numerical analysis based upon the homogenization theory. We got the conclusion by a series of experiment, 1) It is verified that modulus of elasticity of dredged clay is improved by mixing with oyster shells. 2) The homogenization method for deducing apparent modulus of elasticity of oyster shells, which can consider micro-structure of mixed soil, is introduced. The elastic modulus is affected from the skeleton structure of oyster shell. The effect of 49kPa is bigger than that of 98kPa.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.439-444
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• 2008

The oyster shell adsorbents were prepared by steam activation method to evaluate their adsorption characteristics. Washed and pulverized waste oyster shells were prepared by steam activated process in converter at the temperature range of about $700{\sim}800^{\circ}C$ after carbonized at the range of $600{\sim}1000^{\circ}C$. The shell carbonized at $1000^{\circ}C$ showed the best performance among those of other temperature ranges. Also, comparison between gas and liquid phase adsorption was performed to verify adsorbent possibility of waste shell. In case of gas phase, the adsorbent showed lower performance than existing commercial adsorbents. On the other hand, the liquid phase, they showed similar adsorption performance to commercial adsorbents when benzene was used.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.5
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• pp.274-280
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• 2005

Enormous amount of oyster-shell waste has been illegally disposed at oyster farm sites along the southern coast of Korea and then made a serious problem in environmental side. To increase the consumption of oyster shell meal as a soil amendment, the effects of oyster shell meal on soil properties and spring Chinese cabbage productivity were evaluated in silt loam soil to which 0, 4, 8, 12 and $16Mg\;ha^{-1}$ of oyster-shell meal fertilizer were added. Hydrated lime treatment ($2Mg\;ha^{-1}$) was selected as a control. Oyster-shell meal fertilizer, which made by a simple crushing and has high alkalinity as a calcium materials, had significant effects on neutralizing acid soil and on supplying calcium element. Spring Chinese cabbage yields increased with shell meal application. Plant uptakes of macro-nutrients such as P and C, and micro-nutrient such as B were significantly increased by oyster-shell meal application and then contributed to promote Chinese cabbage growth. The highest yield was achieved following the addition of $8Mg\;ha^{-1}$ shell meal application, and the same yield with that in lime treatment was at the $4Mg\;ha^{-1}$. Oyster-shell meal had more substantial effect on suppling calcium and on improving soil pH than that of lime. In conclusion, oyster shell meal fertilizer could be a good supplement to other inorganic soil amendments to improve nutrient balances in upland soils.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.71-72
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• 2017

The oyster shell is lightweight and exhibits strength characteristics similar to sand. In this study, mortar specimens were fabricated by crushing them and processed to 5mm or less of the fine aggregate standard, and examined the fire resistance of the mortar according to changes in particle size distribution. In this experiment, seven particle size distribution conditions were tested. In addition, the mixing ratio was fixed at 1: 3, and the experiment was conducted in terms of the volume ratio because the densities of sand and oyster shells were different.