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Our goal was to verify the manufacturing availability of local Korean natural hydraulic lime (K-NHL) using local Korean low-grade limestone and to test the basic physical properties on the basis of EU standards (BS EN 459-1:2015). We also sought to improve the physical properties of natural hydraulic lime by adding inorganic by-products such as blast furnace slag and silica fume. Where the inorganic by-products were not incorporated, properties such as soundness, air content, particle size, and water absorption (excluding compressive strength and setting time) did not show significant differences with the physical properties evaluated based on EU standards. Also, in terms of the composition of hydraulic phase, local Korean NHL A5 and A8 were similar to NHL 2 of EU standards, whereas local Korean NHL HL correlated with NHL 3.5 or NHL 5. When inorganic by-products were added, the compressive strength and setting time were improved.

Circulating fluidized bed combustion (CFBC) power generation technology is known to efficiently reduce the emission of air pollutants, such as SO2 and NO2, from coal combustion. however, CFBC coal ash contains high contents of free CaO, making it difficult to recycle. This research has been conducted to find ways to use the self-hardening property of CFBC coal ash, one of its inherent characteristics. As part of these efforts, the present study intended to investigate the properties and desulfurization efficiency of Ca-based desulfurization sorbents using CFBC fly-ash as a binder. Limestone powder was mixed with CFBC fly-ash and Ca(OH)2 to fabricate desulfurization sorbents, and it generated hydrate of cement, including portlandite, ettringite, and calcium silicate, etc. The compressive strength of the desulfurization absorbent prepared by CFBC fly ash and Ca(OH)2 was 72&ndash, 92% that of the desulfurized absorbent prepared by using general cement as a binder. These absorbents were then compared in terms of desulfurization efficiency using a high-temperature fluidized bed reactor. It was confirmed that the desulfurization absorbents fabricated using CFBC fly-ash as a binder achieved the best performance in terms of absorption time, which reflects the time taken for them to remove over 90% of high-concentration SO2 gas, and the conversion ratio, which refers to the ratio of CaO turning into CaSO4.

Characteristics of wet flue gas desulfurization and in-furnace desulfurization of domestic and overseas limestone with different crystallinity and crystalline size are studied in this article. Properties of desulfurization were evaluated in relation to physicochemical/mineralogical characteristics, degree of pore formation for different calcination temperatures and TNC(total neutralizing capability). TNC of domestic high crystalline limestone was lower than that of overseas one. On the other hand, the porosity after calcination was shown to be relatively high for domestic limestone, which had high initial rates of desulfurization reactions in-furnace. Based on low pore formation and porosity with high TNC of crystalline high-Ca limestones compared to macrocrystalline ones, the former are preferred for wet desulfurization processes.

In this study, the strength properties of NHL based mortar with blending basalt fiber were investigated. In the first step, it was evaluated that physical properties of NHL based mortar according to mixing method of four types of basalt fiber and then mixing method of one type was selected. As a result of assessment, it showed that the physical properties with mixing method of dry blending were better than that of wet blending and mixing method that basalt fiber pre-mixed with NHL for 5 min in a blender was selected and water and aggregate were finally added. Secondly, the investigation of blending fiber length on the compressive and flexural strength for basalt fiber reinforced NHL based mortars was carried out. The compressive strength was decreased with adding fiber, and the flexural strength was increased more than plain mortar. In the case of adding 6 mm fiber, the compressive and flexural strength were improved more than that of others.

Natural hydraulic lime (NHL) is produced by burning a form of low-grade limestone containing silica and alumina which, above certain temperatures, combine with calcium oxide. The resulting silicates and aluminates impart hydraulic properties to the product. This study aims to determine the calcined characteristics of NHL using domestic low-grade limestone with maximized hydraulic properties. Six types of low-grade limestone containing SiO2 were selected and experiments were carried out with different burning temperatures and holding times. The burning temperature and holding time as the most suitable burning conditions were 1,200oC to 1,300oC and 3 to 7 h, respectively, for the manufacturing of NHL from domestic low-grade limestone. These results demonstrate the feasibility of NHL using domestic low-grade limestone to produce NHL.

The main mineral phases of natural hydraulic lime (NHL) as a hydraulic lime binderare Ca(OH)2, C2S, C3S, C3A, and SiO2 residues. Also, NHL has the characteristic of setting and hardening by a hydration reaction with water and by carbonation reactions with carbon dioxide from the air. In this study, in an effort to investigate changes of the mineral phases by NHL hydration and carbonation reactions, transitions of mineral phases and the microstructures of hardened pastes were analyzed by XRD, DSC, SEM, and by pore size distributions using domestic and foreign-sourced NHL pastes after curing at 1, 3, 7, and 28 days. On the basis of the analysis results, it was confirmed that domestic low-grade limestone can be used for the manufacturing of NHL. The main hydration mineral phases were Ca(OH)2, CaCO3, C2S, and SiO2 residues, while in the case of foreign-sourced NHL, a small amount of an aluminium hydration phase formed. Also, the CaCO3 content after the carbonation reaction increased with an increase in the curing time. After hydration for 28 days, NHL containing considerable amounts of C2S and C3S showed higher carbonation ratios than others types.

This study aims at reviewing satisfaction on facility modernization project of traditional market by case study on integration & move method of 2 markets (Seongbuk 5 day market & Geumgye daily market). Following this study, it asked 182 merchants & customers at Naju Moksagoeul Market about satisfaction and performance on integration & move and the facility modernization project of traditional markets. According to results of the survey, not only merchants but also customers are satisfied with the modernization project. But in detail, valuations between 5 days market and daily market, and between merchants and customers are different. For example, merchants regard as negative, but customers as positive about move of the markets from city to outside. About half of respondents answer that number of market visits and sales volume after move of the markets are higher than before. More than 80% of respondents answer that culture & tourism market programs are helpful to the market revitalization.

This study investigated a utilization technology of light burned dolomite. light burned dolomite () generated in furnace (steel manufacturer) is an alternative to quick lime. Using light burned dolomite has an effect on reducing the consumption of fluorite slag MgO concentration in supersaturated solution by prolonging the life of softening effect. Armophous MgO, not containing periclase is formed by firing dolomite under . It has larger surface area and higher reactivity than periclase, and also shows better expansion effect than quicklime. Due to those effects, therefore, armophous MgO produced from light burned dolomite is used as an alternative expansion agent in mortar. In the experiment, characteristics of light burned dolomite were compared to those of existing expansion agents such as anhydrite and quicklime. Then, each expansion and shrinkage rates were measured over a period of about 3 months in both of 1m Jis mold at labscale and apartment mortar flooring at field scale. In the result, it was observed that light burned dolomite in mortar flooring more compensates for the expansion and shrinkage rates than the existing expansion agents, showing low expansion rate of below 0.05% and also decreases the crack.

Current, Registration fields of CDM projects are being conducted in a variety of parts such as mostly energy, chemical processing and manufacturing processes. However, there are not many CDM project registrations by recycling of inorganic waste. In this paper, analysis abroad CDM project and applications in order to review possibility of CDM project registration through the recycling of domestic inorganic waste were investigated. As a results, registered case of CDM project by inorganic waste recycling was researched to registrate in raw material alternative field of cement industry that inorganic waste can be used in large quantities. Application prospects of CDM project in Korea will be possible to analysis industrial scale, industry using inorganic raw materials, green house gas emissions and inorganic waste generated in large quantities.

In this paper, we present a set of numerical schemes to solve the Muller integral equation for the analysis of electromagnetic scattering from arbitrarily shaped three-dimensional (3-D) dielectric bodies by applying the method of moments (MoM). The piecewise homogeneous dielectric structure is approximated by planar triangular patches. A set of the RWG (Rao, Wilton, Glisson) functions is used for expansion of the equivalent electric and magnetic current densities and a combination of the RWG function and its orthogonal component is used for testing. The objective of this paper is to illustrate that only some testing procedures for the Mulier integral equation yield a valid solution even at a frequency corresponding to an internal resonance of the structure. Numerical results for a dielectric sphere are presented and compared with solutions obtained using other formulations.

The effect of the impurity ions Al3+, Fe3+ and Mg2+ on the formation yield and crystal properties of precipitated calcium carbonate(PCC) produced by the carbonation process was investigated in Ca(OH)2-H2O-CO2 system. The effect of the impurity ions Al3+, Fe3+ and Mg2+ on the formation yield using particle size distribution and morphology of PCC were discussed. The particle size distribution of PCC was increased with increase of impurity ions. The morphology was transformed in order of spheroidal, scalenohedral, rhombohedral calcite for Al3+, Fe3+ and rhombospheroidal, spherical, scalenohedral for Mg2+ with increase of impurity ions.

Non-isothermal behaviors of calcium carbonate using Danyang limestone were investigated. It was attempted to provide non-isothermal data with a precision sufficient for the determination of reliable decomposition behaviors and for the estimation of accurate kinetic parameter. The decomposition temperature of calcium carbonate on the onset, peak and final point were measured. Reaction rate was decreased and maximum reaction temperature was increased with increasing heating rate. Activation energy of Danyang limestone was 45.14㎉/㏖ and 50.80㎉/ ㏖ by Kissinger method and Freeman method, respectively.

The effect of alkali activator and fineness of slag on the physical properties of blast furnace slag cement was investigated. Na2SO4 was used as an alkali activator in this study. Blast furnace slag cement was prepared from mixture of blast furnace slag, ordinary Portland cement, and anhydride gypsum. The fluidity and the compressive strength according to each mixture ratio of them were analyzed by using statistical analysis in order to discover the parameters influencing the fluidity and compressive strength. The results showed that the hydration of blast furnace slag took place by addition of Na2SO4, and ettringite with column-crystalline was created as main hydration product of blast furnace slag. And it is found that the compressive strength of blast furnace slag cement tends to increase as ordinary Portland cement content is higher until 3 days. However, it is also known that the compressive strength tends to increase with the increase of higher blast furnace slag content, along with increase in the OPC on 28 days. As a result of this analysis, it is considered that the ordinary Portland cement content influences the initial compressive strength of blast furnace slag cement, and that in later days is greatly influenced by slag content.

This study has been carried out to use the waste sludges generated at Pohang Iron & Steel Co. Ltd. (POSCO) as the raw materials of Ordinary Portland Cement (OPC). The burnability index of the raw mixture and the hydration characteristics and compressive strength of clinker have been examined. The waste sludges were mainly composed of CaO, SiO 2 , Al 2 O 3 , and Fe 2 O 3 , the main component of OPC. The Burnability index of mixture was improved, according to the replacement content of POSCO sludge increase. POSCO sludge can be used as a raw material for cement because the state of mineral development and property of clinker produced from POSCO sludge are similar to the plain. Therefore, POSCO sludges can be used as the source materials of iron and calcium oxide.

It has been proved that co-cultivation of human neuroblastoma cells and human fibrolast cells can enhance nerve cell growth and the production of BDNF in perfusion cultivation. In batch co-cultivation, maximum cell density was increased up to 1.76×106 viable cells/mL from 9×105 viable cells/mL of only neuroblastoma cell culture. The growth of neuroblastoma cells was greatly improved by culturing both nerve and fibroblast cells in a perfusion process, maintaining 1.5×106 viable cells/mL, which was much higher than that from fed-batch cultivation. The nerve cell growth was greatly enhanced in both fed-batch and perfusion cultivations while the growth of fibroblast cells was not. It strongly implies that the factors secreted from, human fibroblast cells and/or the environments of co-culture system can enhance both cell growth and BDNF secretion. Specific BDNF production rate was not enhanced in co-cultures; however, the production period was increased as the cell growth was lengthened in the co-culture case. Competitive growth between nerve cells and fibroblast cells was not observed in all cases, showing no changes of fibroblast cell growth and only enhancement of the neuroblastoma cell growth and overall BDNF production. It was also found that the perfusion cultivation was the most appropriate process for cultivating two cell lines simultaneously in a bioreactor.