• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.639-644
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• 2009

This study presents the new idea of liquid desiccant system with extended surface to reduce the system size. The extended surface is inserted between vertical cooling/heating tubes to increase the mass transfer area, and the liquid desiccant flows through the tube wall and the extended surface. Mathematical models for heat and mass transfer between liquid desiccant and air stream at tube wall and extended surface are provided. Dimensionless design parameters governing heat and mass transfer phenomena around the tube and the extended surface are identifier, and dimensionless operating parameters depicting system operating condition including flow rate ratio between dehumidification/regeneration processes, and mass flow rate ratio between air stream and liquid desiccant are explained. The effects of the parameters on system performance are summarized.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.4
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• pp.303-311
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• 2011

This study presents a new idea of liquid desiccant dehumidifier with extended surface to improve the compactness. Extended surface is inserted between vertical cooling tubes, and the liquid desiccant flows down along the tube walls and the extended surface as well. Though the extended surface contributes to the increase in the mass transfer area, the effect tends to be limited because less conductive non-metallic materials need to be applied due to the high corrosiveness of liquid desiccant. To analyze the effects of the extended surface insertion, mathematical modelling and numerical integration are performed for the heat and mass transfer in the liquid desiccant dehumidifier. The results show that, though the liquid desiccant on the extended surface is heated due to the moisture absorption, the temperature can be maintained by periodic mixing at the contact points between the tube and the extended surface with the liquid desiccant stream from the tube side at a relatively low temperature. This implies the absorption heat from the extended surface side can be removed effectively by mixing, which leads to a substantial improvement of the dehumidification in the liquid desiccant dehumidifier with extended surface. When the interval of the extended surface, $p_e/L$, is less than 0.1, the dehumidification is shown to increase by more than two times compared with that without extended surface.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.2
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• pp.73-78
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• 2009

The decay heat of Cs and Sr contained in a LiCl waste salt, generated from an electrolytic reduction process in pyroprocessing of spent nuclear fuel, has been calculated. The calculation has been carried out under some assumptions that most of the LiCl waste is purified and recycled to main process, and the residual is fabricated to make a waste form. As a result, the decay heat from daughter nuclides such as Ba and Y seems to be maximum 4.6 times higher than that from their parent nuclides such as Cs and Sr. The thermal release from Cs and Sr in the LiCl waste is the maximum around the first one month, so an cooling system operation for some time at the beginning would be suggested to control a rapid increase in the temperature of the LiCl waste salt.

• Membrane Journal
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• v.20 no.4
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• pp.304-311
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• 2010

In this study, loose RO hollow fiber membranes using CTA polymer were prepared by phase inversion method and their water purification properties were tested. 1,4-dioxane and LiCl was used as a skin layer formation agent and pore formation agent, respectively. Water flux, salt rejection, chlorine resistance, MWCO and membrane morphology were evaluated as a function of the dope composition. When the membrane prepared using the dope solution of CTA/NMP/1,4-dioxane = 18/72/10 (wt%) with air gap of 30 cm, it shows improved RO performance such as $20.5L/m^2hr$ of water flux, 60% of NaCl rejection, 10,000 ppm/hr of chlorine-resistance and around 5,000 Da of MWCO.