• Resources Recycling
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• v.3 no.3
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• pp.32-49
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• 1994

Hydration process is one of the basic carbonation system. Limestone sludge produced in Pohang Iron & Steel Co., Ltd. We tested for identify of hydration characteristics. The result obtained in this study can be summarized as follows; 1. The classify of limestone sludge is type of ground calcium carbonate(-3mm+325mesh)and the major mineral of calcite, and further more high grade(CaO 51%), fine powder(15~22$\mu\textrm{m}$). 2. Limestone sludge mixed two process sludge, first one is washing process sludge and the other one is wet collect kiln dust. The composition rate is about 8:2. Wet collect kiln dust is major mineral of calcite, too. But the sludge is assumed to one by quick lime, slaked lime and unreacted natural limestone. So, the ideal process is dividing of the washing process sludge and wet collect kiln dust. 3. We manufactured of slaked lime from limestone sludge. To investigate the effect of hydration reactor, the experiments was done with various reactor type as magnetic stirrer, shaking incubator and ultrasonic vibration reactor, respectively. Generally, ultrasonic vibration reactor is excellent hydration for limestone sludge and produced very fine slaked lime powder with ideal distribution. 4. The optimum condition is 10% pulp density, when the manufacture of fine slaked lime powder by ultrasonic vibration reactor. And hydration times to compare the results of the study with ultrasonic vibration reactor of generalized most short time(5~10 min). 5. Finally, the dispersive characteristics of slaked lime powder measured 1~5 $\mu\textrm{m}$ from limestone sludge were compared with those of natural limestone ones(10~20$\mu\textrm{m}$), in order to check applicability of slaked lime with hydration process from limestone sludge.

• Korean Journal of Poultry Science
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• v.47 no.4
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• pp.211-217
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• 2020

This study evaluated calcium hydroxide (slaked lime) and a combination of plant extracts ('natural product'; clove, cinnamon, and saponin; 1:1:1 ratio) as acaricidal control mechanisms for poultry red mites. Red mite susceptibility was evaluated after treatments with 10% slaked lime, 20% slaked lime, and 1% natural product. The duration of the acaricidal effect was also tested at 0, 10, 30, and 60 min after treatment using 20% slaked lime, 1% natural product, or a mixture of both. In the in vitro experiment, the slaked lime treatments were 73.2% (10% slaked lime) and 85.1% (20% slaked lime) effective on red mites. In acaricidal effect of control materials over times, with 20% slaked lime, the acaricidal effect decreased to 50.7% after 30 min, and 12.7% after 60 min (P<0.05). With 1% natural product, there was no acaricidal effect after 30 min (P<0.05). With 20% slaked lime +1% natural product, all of poultry red mites died until 30 min, and 92.9% after 60 min (P<0.05). On the farm, poultry red mites were observed that the number of poultry red mites increased 7,923 from 36 to 45 weeks, but then decreased to 483 after 20% slaked lime plus 1% natural product treatment. These results indicate that combining slaked lime and plant extracts effectively control poultry red mites.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.505-512
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• 1999

Soft marine clay deposits pose several foundation problems. Generally, lime stabilization is used worldwide for solidifying of soft marine clay deposits. In this paper, a series of laboratory tests were conducted to verify clay-lime reaction. A clay was collected from Pusan, which was mixed with various quantities of quick lime and slaked lime. Various compounds produced by clay-lime reaction were identified by X-ray diffraction analysis. The physico-chemical properties of the clay were also investigated. Compounds such as calcium silicate hydrate (CSH), calcium aluminate hydrate (CAH), calcium aluminate (CA), hillebrandite, and gehlenite were identified. It is likely that such compounds were mainly produced by pozzolanic reaction. Based on the change of physico-chemical properties obtained by the reaction, the water content was considerably decreased when lime was added to the clay. In addition, unconfined strength was increased. In the other hand, quick lime was more effective than slaked lime in decreasing and increasing of the water content and unconfined strength, respectively. Fewer cracks were produced when the clay was mixed with quick lime. It is suggested that these beneficial changes produced by the mixing of the clay and lime depend on the properties of compounds obtained by chemical reaction.

• Korean Journal of Environmental Agriculture
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• v.16 no.2
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• pp.175-180
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• 1997

This experiment was conducted to find out the effects of lime materials application on reducing injury of simulated acid rain(SAR) in soybean grown in pot contained with sandy loam. Six treatments including control, slaked lime(SL), 1% and 2% lime water(LW) and composite treatments with SL+LW were applied. Slaked lime was applied to soil in pot before planting, and lime water was applied to leaves a day prior to the spray of SAR(pH 2.7) and normal rain(pH 6.0), and these were sprayed at 2-day intervals. Growth, yield and yield components, foliar injury rate, chrolophyll content and photosynthetic activity in leaves, content of mineral nutrients in plant and soil chemical properties were analyzed and investigated. These results obtained are summarized as follows : Seed yield of all lime treatment was reduced by SAR compared with control. But seed yield of all lime treatment was increased with treatment of lime material in soil and on leaves. After 15 and 45 times spray of SAR, all lime treatments were effective in injury reducing visible injury of leaves compared with none treatment. Chlorophyll content in leaves was highest in plants treated with slaked lime+ 1% lime water and photosynthetic activity was highest with treatment of slaked lime. Concentration of total nitrogen, phosphate, and sulfur in soybean plant were increased by the spray of SAR. Concentration of total nitrogen, potassium and calcium in soybean plant were increased with treatment of slaked lime into soil. By treatments of SAR, soil pH was decreased, and total nitrogen and sulfur concentration in soil were increased. However, available phosphate and exchangeable cations in soil such as calcium, magnesium and potassium were reduced. Soil pH, calcium and silicate concentration were increased with treatment of slaked lime into soil.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.4
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• pp.174-178
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• 2008

Nano-crystalline slaked lime was synthesized using design of experiment. In order to synthesize slaked lime, calcium chloride $(CaCl_2)$ and urea were used as starting materials. Calcium chloride solution and urea solution were mixed and heated in vessel that calcium carbonate was precipitated during heating. Precipitates were filtered, washed several times using D.I.water and ethanol and finally dried in oven. Slaked lime $(Ca(OH)_2)$ has been fabricated by the hydration of calcined $CaCO_3$. Design of experiment (Taguchi method) was used to optimize parameter, to minimize noise factors of experiment and to statistically analyze the results. Slaked lime having about 50 nm in optimized crystallite size could be obtained by calcination of $CaCO_3$ at $1000^{\circ}C$ for 0.5 h and hydration with D.I water containing ethanol and oxalic acid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.10
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• pp.61-71
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• 1971

This study was conducted in order to investigate the effects of slaked lime and borax on the Akiochi paddy field. The pot trial(slaked lime was treated 0, 6, 10, 15g and borax 0, 0.75, 1.5g per pot) and the field trial(slaked lime was treated 0, 100, 200kg and borax 0, 10, 30, 50kg per 10are) respectively. The results are summarized as fo11ows. I. Pot Trial: 1. In a heavy treated of borax, appeared chlorosis on whole leaves(bottom) in early growing stage, However, in about 25 days after transplanting, these chlorosis were disappeared gradually. And in proportion to close by maturity after the ear-heading, changed to dark brown color and rolled at the end of upper leaves, finally withered. At the same time the part of the end of grains was also colored to dark brown. 2. Slaked lime effected to increase the ti1lering, hence increased the number of ear, on the other hand, borax showed the tendency of repression the tillering, conversely. 3. Borax effected to hurried up to heading date of rice plant, to which borax had been the plot of B$_1$ to 3 days and B$_2$ to 5 days, hurried up than control respectively, regardless of the quantities of slaked lime application. 4. According to the application of borax, the length of culm were shortened, otherwise the length of panicle were longished, then no recognized the. independent effect of slaked lime. 5. The number of grains per panicle were seemed like increased by treatment of slaked lime, but the grain were decreased in the heavy treatment of slaked lime and borax. These phenomena were showed in ratio of maturity likely tendency as above. 6. In the 1, 000 grains weight of brown rice, in the case of slaked lime was almost no significant, otherwise by increase the application of borax, increased the weight of 1, 000 grains and the size of the grains was greater. 7. The weight of rough rice and straw were showed the same tendency as the number of grains and maturity ratio. particularly, showed the phenomenon of the reduction by the heavy application of borax. II. Field trial: 1. In a heavy treated of borax, appeared chlorosis in a early growing stage, according to close by maturiting date after the ear-heading changed to dark brown the end of upper leaves, finally dried. 2. Slaked lime application accelerated the growth and increased the number of ear, but borax showed the tendency of repression the tillering. 3. Borax effected to hurried up to heading date of rice plant, according to heavy treatment of borax quickened heading date for 4 to 5 days. 4. As a whole, culm length was repressed by borax treatment. 5. Borax application 10kg per 10are advanced progress the maturity, but in the case of above 30kg per 10are of borax showed the tendency obstruction the maturity. 6. The yield of rough rice and brown rice recognized the independent effect of slaked lime and borax, respectively. the yield was decreased by the abundant of borax.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.509-516
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• 2023

The use of sulfur(S) in concrete has been variously studied as a way to improve salt resistance in concrete. However, sulfur is a solid material and is difficult to powder, which has disadvantages in its usability as an admixture or mixture for cement and concrete. For these problem, polymers such as dicyclopentadiene have been used to modify sulfur, but this also exists in a sticky state after modifying and does not improve the fundamental problem. So, reforming sulfur with slaked lime and the effect on cement hydration was examined by reforming sulfur with slaked lime, and the following conclusions were obtained. Depending on the reaction conditions, slaked lime modified bio-sulfur exists in a slurry state containing unreacted sulfur, unreacted slaked lime, calcium-sulfur(Ca-S) compounds and water. When slaked lime modified bio-sulfur is used as a cement mixture, salt resistance of concrete with slaked lime modified bio-sulfur is to be superior to that of plain concrete. This is believed to be because structure of cement hydrates with slaked lime modified bio-sulfur is to be more dense to that of plain cement hydrates by the continued presence of ettringite and can be used as a cement mixture in concrete.

• Korean Journal of Agricultural Science
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• v.42 no.4
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• pp.415-421
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• 2015

Ca is material to used in Chinese cabbage (Brasica rapa L. spp. pekinensis). The variation of inorganic ions and GSLs in Chinese cabbage cultivated to control additional Ca contents in slaked lime. The additional fertilizer of slaked lime differ four grade that 0 g (Ca-0), 0.28 g (Ca-1), 0.56 g (Ca-2), 0.84 g (Ca-3) are week intervals with a total of 8 times after transplanting. Inorganic ions in Chinese cabbage ('Bulam plus') were analyzed to use inductively coupled plasma atomic emission spectometry(ICP). The more additional slaked lime input, the more almost macronutrients contents were high except Ca. Ca contents were higher in Ca-0 (153.10) and lower in Ca-3 (130.55 mg/kg dry weight, DW). GSLs were identified based on peak retention time in previous results of our laboratory. Seven GSLs including two aliphatic (gluconapin, glucobrassicanapin), one aromatic (gluconasturtiin), four indolyl (glucobrassicin, neoglucobrassicin, 4-methoxyglucobrassicin, 4-hydroxyglucobrassicin) were detected using HPLC. Progoitrin, 4-methoxyglucobrassicin, and gluconasturtiin contents increased in proportion to the input in additional slaked lime. Total GSLs contents were Ca-0 (11.95), Ca-1 (17.02), Ca-2 (19.63), Ca-3 ($17.11{\mu}mol/g$ dry weight, DW). Total Ca and GSLs contents (Ca-1,2,3; mean 17.92) are higher than non treatment (Ca-0; $11.95{\mu}mol/g$ DW).

• Korean Journal of Environmental Agriculture
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• v.6 no.1
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• pp.25-30
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• 1987

This study was conducted to find out the effect of several improvers such as triple super phosphate, slaked lime, wollastonite and gypsum for reducing Cd content in brown rice. Several improvers were applied to two different types of soils which are contaminated with copper-zinc mine wasted and sludge.(Soil I contained Cd : 7.88, Cu : 57.9, Zn : 175.0 ppm, Soil II contained Cd : 3.95, Cu : 30.2, Zn :124.0 ppm) In general, effects of improvers on reducing content of Cd, Cu and Zn in brown rice were greater in soil I than soil II. In soil I, the Cd content of brown rice was reduced to 0.4ppm below by application of triple superphosphate, fused phosphate, slaked lime and gypsum, 98, 225, 190 and 276Kg/10a, respectively. Triple superphosphate was more effective than fused phosphate in reducing uptake of Cd, Cu and Zn by applying them as an equal amount of phosphorous, also to equal alkalinity, slaked lime had the highest effect. Negatively linear effect was found between soil pH and Cd and Zn content in brown rice. As to above results, it was no doubt that triple superphosphate, fused phosphate and slaked lime would be applied to reduced heavy metals in brown rice. The slaked lime, triple super phosphate and fused phosphate were available to reduce uptake of Cd, Cu and Zn by rice plant grown in the soil contaminated with mine waste and sludge.

• Journal of the Mineralogical Society of Korea
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• v.31 no.4
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• pp.267-275
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• 2018

The purposes of this study were to analyze the mineralogical characteristics of slaked lime used for wall repair of traditional buildings in Bagan, Myanmar and to evaluate the physical properties of lime plaster produced by the same method as Bagan region. In the X-ray diffraction and thermal analysis of the Myanmar slaked lime, portlandite ($Ca(OH)_2$) and brucite ($Mg(OH)_2$) were detected as main constituent minerals, and a carbonate rock mainly composed of dolomite ($CaMg(CO_3)_2$) minerals may be used as a raw material to make slaked lime. The field-emission scanning electron microscope analysis showed that the Myanmar slaked lime was composed of irregularly shaped crystals of $0.5{\mu}m$ or larger and a small amount of $0.1{\mu}m$ of plate - like crystals. The size and uniformity of crystals in Myanmar lime is different from that of Korea slaked lime. This may be attributed to the effect of the mineral composition and the lime hydration method of Myanmar, which produces slurry by immersing the burnt lime in excess water for a long period of time. The compressive strength of the lime plaster in Myanmar resulted in a mean value of $1.13N/mm^2$ for the specimens cured for 28 days. The strength of the specimens with Bale juice was $1.03N/mm^2$, respectively. The lime is an air setting material that exhibits strength through long carbonation process. Therefore, it is necessary to evaluate physical properties according to curing period through long-term curing over 28 days in the future.