• Korean Journal of Soil Science and Fertilizer
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• v.23 no.2
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• pp.107-113
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• 1990

In comparision with calcium sulphate, the effect of calcium-carbonate, -silicate and -hydroxide on desalinization of tidal saline soil was investigated in a continuous leaching column experiments after mixing with an equivalent amount of Ca to sodium plus magnessium in the saline soil. One half of liming materials was mixed to the top one-tenth of column soil and the remainder was spread on the surface. Results obtained are as follows ; 1. Gypsum made easy to percolate and desaline (Na) tidal marine soil but accumulated magnessium in subsoil. 2. $Ca(OH)_2$, $CaCO_3$, and $CaSO_3$ precipitated Mg in the soil which limes were mixed, but they washed down magnessium more severely from the immediate bellow the limed soil and less from the subsequent soil layers. This leaching was more severer at the treatment of $Ca(OH)_2$and lowest at the treatment of $CaSiO_3$. 3. The alkalinity of lime in addition to the dissociation of exchangeable Na raised pH of limed leached tidal soil and slowed down the percolation rate which retarded desalining Na from limed saline soils. This effect was most severe in the $Ca(OH)_2$ treated soil. 4. pH of leached soils was correlated possitively with exchangeable Na and negatively with exchangeable Mg giving follwing relationship pH= 7.77+0.489 Na/Mg r = 0.845.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.514-519
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• 2001

Converter has been slag produced 10 million tons per year in Japan. It is a steel making by product produced in the same way as the blast-furnace slag. Though blast-furnace slag is being used effectively as a concrete admixture, the converter stag has never been used effectively because of the expansion action of contained free lime and iron oxide. This is an important environmental problem in the steel industry. Beta-2CaOSiO$_2$(beta-C$_2$S) is contained 40 percent in converter slag, therefore it is very promising as a concrete admixture. We proposed an accelerated aging processes capable of stabilizing the converter slag in a short time. The converter slag is dipped into alkali aqueous solution after heating at low temperature. It was subsequently ground to a grain size of 75 ${\mu}{\textrm}{m}$ , inner 30 percent of OPC. The properties of mortar and concrete using the blended cement were determined. As a result, it has become apparent that the expansion was reduced and long term compressive strength was increased while that at early ages was not so remarkable. The hydration exotherm rate was lower than that of the OPC.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.1
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• pp.29-34
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• 1974

On a newly reclamed acidic Song-jong soil (soil of a member of fine loamy, mesic family of Hapludults) an experiment was carried out to find out the proper measure of the improvement of soil fertility with soybean as test crop. Results are summarized as follow: 1. Application of compost (1 ton/10a), lime (lime requirement)and fused phosphate (equivalent to 5% of the phosphate fixation coefficient)resulted in the increase of soybean yield by 93.3% over the check plot (N: 6kg/10a, $P_2O_5$: 9kg/10a, $K_2O$: 6kg/10a). The application of fused phosphate at the level of 5% of phosphate fixation coefficient N (6kg/10a) and K(6kg/10a) brought the yield increase by 62.7% over the check plot. However, although the pH of the soil was adjusted to 7.0 by liming, the application of lime with moderate dose of phosphate ($P_2O_5$: 9kg/10a) did not increase the yield of soybean significantly. And the application of fused phosphate at the level of 5% of phosphate fixation coefficient increased the available soil P from 14 ppm to around 100 ppm as tested after harvest. 2. Application of compost (1 ton/10a) increased the organic matter content of soil by 0.8% when tested after harvest. While, the application of rice straw (0.5 ton/10a) did not alter the soil organic matter content. The CEC of the soil tested after havest found incereased significantly by the addition of lime and compost. 3. Plant analysis revealed that the $K_2O/Ca+Mg$ is better correlated with the yield than the absolute concentration of $K_2O$ in plant tissue. Between the concentration of $P_2O_5$ in plant tissue and the yield of soybean, a typical C-curve relationship was observed, indicating that in this particular soil, phosphate was the primary growth liming factor.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.6
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• pp.334-339
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• 2005

Although phosphogypsum can have profound effects on both the physical and chemical properties of certain soils with supplying the essential elements, no widespread use of by-product phosphogypsum will be made unless such uses pose no threat to the public health and soil contaminations. This study was conducted to evaluate the effects of phosphogypsum on the growth of oriental melon and soil properties in plastic film house. Phosphogypsum was treated at the rate of $70kg\;CaO\;10a^{-1}$ and the effects were compared with the treatment of Ca-Mg carbonate. In the treatment of phosphogypsum, early growth of oriental melon was significantly increased comparing to the growth in the Ca-Mg carbonate treatment. Total fruit yield was not different between the treatments of phosphogypsum and Ca-Mg carbonate, but marketable fruit yield was higher in the phosphogypsum treatment. Although Ca and S contents in oriental melon were increased in the phosphogypsum treatment, contents of toxic heavy metals including As, Cd, Cr, Cu, and Pb were not different between the two treatments. Also, soil pH and contents of extractable toxic metals in the soil were not significantly different between the two treatments after the experiment. These results suggest that phosphogypsum can be a valuable substitute for lime materials in high pH soils of plastic film house.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.4
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• pp.244-251
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• 1991

This study was undertaken to assess the effectiveness of magnesium-and boron-enriched complex fertilizer(CF, N-P$_2$O$_{5}$-K$_2$O-MgO-B$_2$O$_3$: 14-10-12-3-0.2) on the maintenance and management of hilly pasture. The effectiveness of CF was compared to those of some straight fertilizers (SF). This first part of the study was concerned with the soil chemical properties and the mutural balances of mineral nutrients in the soils of a mixed grass-clover and a pure grass swards. The results of a two-year field experiment are summarized as follows: 1. The Mg contents in the soils of the CF plots were higher than those of the SF plots. On the other hand, the Ca contents were higher in the SF plots than in the CF plots. The contents of Mg and Ca, and CEC, except K, in both the CF and SF plots were considerably below the optimum levels. At the normal application rate of NPK, the contents of available P$_2$O$_{5}$ were close to the optimum level in both the CF and SF plots. 2. The contents of exchangeable Mg were lower than the K contents in soils of all the plots. At the normal application rate of NPK, the Mg contents in the CF plots, but not in the SF plots, were close to the critical level for general crops (0.29me Mg/100g soil). The Mg contents in soils of all the plots, however, were considerably below the critical level for pasture forages and grazing cows (0.41me/100g). 3. Considering the desirable base saturation level of soil, the saturation levels of Ca and Mg were insufficient in both the CF and SF plots. The saturation levels of Mg in the CF plots, however, were relatively good compared with the SF plots. The equivalent ratios or Mg/K, Ca/Mg. Ca:Mg:K, and %Mg of CEC in soils were generally unfavorable in all the plots. These ratios of the CF plots, however, were relatively better than those of the SF plots. 4. Considering the contents of exchangeable Ca and Mg in soils, it is suggested that the application of slaked magnesium lime as a soil amelioration might be desirable for the fundamental increment of those contents at pasture establishment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.379-385
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• 1987

A field experiment was conducted to find out the effects of liming (soil pH) and sources of N on the chemical constituents of soil and leaf lamina of burley tobacco. Treatments consisted of liming (nonliming, liming to soil pH 5.5 and 6.5) as the main plot and N sources［compound fertilizer of containing 3.9% $NH_4-N$ and 6.1% $NH_2-N,\;NaNO_3,\;(NH_2)_2CO\;and\;(NH_4)_2SO_4$］as the sub-plot. The soil pH was high in $NaNO_2$ plot, while low in $(NH_4)_2SO_4$. But the differences of Ca concentration in top soil among N sources were not detected. The $NO_3-N$ concentration in top soil was high in high limed and $NaNO_3$ plot. The $NO_3-N$ content of leaf (lamina) at 75 days after transplanting was high in $NaNO_3$ plot and CaO con-tent of leaf at 45 days after transplanting was high in high limed plot. But neither liming nor N source had effect on the contents of total nitrogen, $P_2-O_{5}\;and\;K_2O$ of leaf during growing season. There was no significant differences in total alkaloid and total nitrogen contents of cured leaf (lamina) to liming and N source. But when the source of N was $NaNO_3$, the content of total alkaloid was increased by adding lime. When the source of N was $(NH_4$)_2SO_4$, the content of $K_2O$ in cured leaf was high while CaO was low. But neither liming nor N source had effect on the contents of $P_2-O_{5}$ and MgO in cured leaf.

• Resources Recycling
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• v.33 no.3
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• pp.12-20
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• 2024

The global cement industry emits approximately 2.9 billion tons of greenhouse gases, of which 1.74-1.89 billion tons are emitted from limestone, which is the main raw material for clinkers. Therefore, the feasibility of using slag, a non-carbonated CaO-based raw material, must be investigated, and the physical properties of cement must be considered. In this study, the mixing ratios of the raw mix and properties of cement were analyzed. The CaCO₃ replacement ratio was limited when one type of slag was used; however, when the mixed slag was utilized, the CaCO₃ replacement ratio increased by more than 12 %. The compressive strength of the slag-incorporated cement was lower than that of Ordinary Portland Cement (OPC). Therefore, the lime saturation factor (LSF) of the raw mix and fineness of the cement were increased to improve the compressive strength. The compressive strength of cement with improved fineness was similar to that of OPC for a CaCO₃ replacement ratio of up to 6 %, and it decreased as the CaCO₃ replacement ratio was increased to 9 %. When both fineness and LSF were increased, the compressive strength and flow value of the cement with a CaCO₃ replacement ratio of 12 % were similar to that of OPC.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1799-1808
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• 2000

To investigate the applicability of loess as a coagulant. the optimum conditions of coagulation and efficiency comparison of several coagulants (PAC, PACS, LAS) in chemical treatment of livestock wastewater were performed. As a result, the optimum mixing ratio of loess and lime(CaO) was 3:7. The optimum dosage of the mixed coagulant was 30 g/L. The optimum speed for rapid mixing of the mixed coagulant was 200 rpm at 1 min. and the optimum speed for slow mixing was 50 rpm at 10 min. The mixed coagulant showed the removal efficiency of turbidity, SS, BOD, $COD_{cr}$. T-P and TKN to 95.8%, 92.5%, 71.6%, 71.1%, 98.2% and 32.5%, respectively, which was better than other several coagulants. The mixed coagulant was possible to use as substitutional coagulants of traditional coagulant, and the producted sludge can use as a soil amendments.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.4
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• pp.286-292
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• 1991

This study was carried out to investigate in influence of inoculation B. sp. and lime types on nutrient content of peanut seed, and the correlation between nutritient contents in seed and plant. 1. Inoculated B. sp., content of crude protein, phenylalanine, isoleucine, cystine, histidine, aspartic acid, serine, and alanine in seed were increased significantly, but that of crude fat was decreased. 2. The content of crude fat was the highest without lime, glutamic acid was the highest with calcium sulfate, valine, phenylalanine, isoleucine, leucine, lysine, aspartic acid, serine, glycine and alanine with slaked lime, and histidine with calcium carbonate. 3. The content of crude protein in seed was negatively correlated with that of crude fat. The contents of chlorophyll, allantoin, ammonia, free amino acid, T-N, $P_2O_5$, and CaO in leaf at 100 days after sowing were positively correlated with the content of crude protein and various kinds of amino acid in seed, but negatively with the content of crude fat. The content of nitrate in leaf at 100 days after sowing showed the result of contrary tendency.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.3
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• pp.219-224
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• 2013

In this study, the inorganic insulating material was fabricated with quartzite, ordinary portland cement(OPC), lime and anhydrous gypsum. After characteristic analysis of slurry, the optimum mixing ratio was derived with different $CaO/SiO_2$ mole ratio. Based on derived mixing ratio, the inorganic insulating material was fabricated at different water content and hydrothermal synthesis conditions. Specific gravity was $0.26g/cm^3$, compressive strength was 0.4 MPa, and thermal conductivity was 0.064 W/mK. This properties were enhanced performance of conventional ALC (Autoclaved Lightweight Concrete). And it can replace organic insulation with harmless inorganic insulation through continues research and development.