• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.2
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• pp.927-935
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• 2011

In-situ California Bearing Ratio(CBR) test has been widely used for evaluating the subgrade condition in pavements. However, because the in-situ CBR test is expensive and takes time for operation, it is difficult to figure out the in-situ characteristics of subgrade strength in detail. For faster and economical operation, the Dynamic Cone Penetrometer(DCP) has been often utilized for estimating the subgrade strength in the field. The purpose of this paper is to determine the relationship between CBR value and DCP index of the embankment constructed with mixtures of soil and waste lime. Waste lime used in this study is producted as a by-product in the manufacturing process of making $Na_2CO_3$ from local chemical factory in Incheon. In this field measurement, the geotechnical tests such as field water content, field density, field CBR test, and dynamic cone penetration test were conducted.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.109-112
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• 2022

Lime has been used for the neutralization of acidic waste because it is cheap and available in large quantities. The resulting sludge often contains a considerable amount of unreacted lime due to alkali overdosing, even during automatic neutralization processes, which mainly arises from the poor solubility of lime. The sludge cake from lime neutralization of Ilkwang Mine also contained high percentages of calcium and magnesium. The elemental content of the sludge cake was compared with those obtained from a simulation of the lime neutralization facility installed at Ilkwang Mine. A Goldsim^® model estimated the degree of lime overdosing to be 19.1% based on the fractions of ferrous oxide. The analysis suggests that resolubilization of aluminum hydroxide could occur in the settling basin, in which pH exceeded 10 due to the continued dissolution of the overdosed lime. The present study demonstrated that chemical analysis of sludge combined with process simulation could provide a reasonable estimate of mass balance and chemistry in a neutralization facility for acid mine drainage.

• Journal of the Korean Society of Safety
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• v.4 no.1
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• pp.75-81
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• 1989

The aim of this study is, by the Lime-Stabilization of decayed Organic Wastes, in preventing the reclaimed Waste from being another pollution due to reclaiming those things. 1. A perfect reaction is possible by the addition of poor Stabilization-Lime of 5 percent in a short time of 5 minute. 2. PH of the Stabilization-handled Wastes rise over 12. 3. Malodorant of Stabilized Wastes is slight because malodorant Volatilize in the course of the Stabilization or is captured in the handled subetance. 4. The second pollution scarcely brings about because a rapid decomposition is impossible on account of the coating of Alkali Substance.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.75-81
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• 2003

To investigate the reinforcing effect of subsurface layers of marine dredged clay(DMC) mixed with the micro-fiber(MF), a series of laboratory tests were performed on the DMC specimens with and without MF through uniaxial and triaxial compression tests. For the test programme, the elapsed time after dredging of marine clay, mixing rate and length of MF, and curing time of the composite were chosen as the important factors affecting the strength behaviour. The strength of the DMC mixed with MF and waste lime(WL) used for the admixture was found to be enhanced with the increasing content and length of MF, and with decreasing water content of DMC. MF and WL were applied as materials for trafficability improvement of the very soft reclaimed ground by DMC.

• Environmental Engineering Research
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• v.20 no.3
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• pp.212-222
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• 2015

Experiments were conducted on the immobilization of eight heavy metals (HMs) (Zn, Cu, Mn, Fe, Ni, Pb, Cd, and Cr) during 20-day rotary drum composting of water hyacinth. The Tessier sequential extraction procedure was used to investigate the fractionation of HMs. The eco-toxicity risk of HMs was assessed by risk assessment code (RAC). In the results, the bioavailability factor (BAF) for different HMs presented in the following order: Mn > Zn = Fe > Cu > Cr > Cd = Pb > Ni. The total concentration of Pb was higher than that of Zn, Cu, Mn, Cd and Cr; however, its BAF was the lowest among these HMs. These results confirmed that the eco-toxicity of HMs depends on bioavailable fractions rather than on the total concentration. The greatest reduction in bioavailability and eco-toxicity risk of HMs occurred in lime 1% and 2% as compared to control and lime 3%. The eco-toxicity risk of Fe, Ni, Pb, Cd and Cr was reduced from low risk to zero risk by rotary drum composting. These studies demonstrated the high efficiency of the rotary drum for degrading compost materials and for reducing the bioavailability and eco-toxicity risk of HMs during the composting process.

• Journal of environmental and Sanitary engineering
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• v.23 no.3
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• pp.1-8
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• 2008

Currently, medical waste stoker incinerator is widely used in the emission control technology of health-care risk waste and miscellaneous contaminated waste. In the past, wet type control technology was used to remove the major harmful gaseous contaminants of medical waste such as HCl, $NO_x,\;SO_2$, CO, DUST, Dioxin. However, the treatment cost for wastewater was high and it has a disadvantage for frozen system during winter season. Therefore, in order to obtain effective treatment, the dry type control technology was developed and widely used to remove the gaseous contaminants. In this study, pre-coated bag filter using hydrated lime, ($Ca(OH)_2$), was applied to the dry type control system and the optimum dose of hydrated lime was investigated. The treatment results showed that the dust collection rate was approximately 26.7%. Moreover, the HCl removal rate using pre-coated bag filter ($50mg/sm^3\;Ca(OH)_2$) was 13.52%, which was significantly higher than 3.26% obtained from conventional bag filter.

• Geomechanics and Engineering
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• v.28 no.3
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• pp.255-263
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• 2022

Lime stabilization has conventionally been listed amid the key techniques of chemical stabilization. Replacing lime with sustainable agro-based by-products have gained prominence in recent decades. Bagasse ash (BA) is one such potential alternatives, an industrial waste with abundance in production, and industries exploring sustainable solutions for its safe disposal. Supplementing BA with lime could be an ideal approach to reduce lime consumption. However, suitability of BA and lime for the stabilization of expansive clays, such as black cotton (BC) soil is yet to be explored. This paper therefore aims to investigate the suitability of BA-lime mixtures to stabilize BC soil with emphasis to compaction behaviors and unconfined compressive strength (UCS) using standard laboratory procedures. Suitability of BA-lime mixture is then assessed against addition of calcium sulphate which, from previous experience, is detrimental with lime stabilization. Experimental outcomes nominate 15% BA as the optimum value observed from both compaction and UCS data, while addition of 4% lime to 15% BA showed the best results. Mineralogical and microstructural analysis show the presence of cementitious compounds with addition of lime and calcium sulphate with curing periods. While, formation of Ettringite needles were noted with the addition of calcium sulphate in BA-lime mixtures (at optimum values) after 90-day curing, and UCS results showed a decrease at this point. To this end, addition of BA in lime stabilization showed encouraging results as assessed from the compaction and UCS results. Nonetheless usage of calcium salts, with utmost emphasis on calcium sulphate and equivalent should be avoided.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.519-526
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• 2005

Hydrolysis of soda-lime waste glass was investigated to test the feasibility for use of waste glass as feed material in the production of foamed glass. The soda-lime glass, such as plate glass and various bottle glasses, was effectively hydrolyzed by steam and water under high pressure. The proper condition for the hydrolysis was found to be reaction temperature of $250^{\circ}C$ and reaction time of 2 h. Under this condition, the water content of hydrated glass through hydrolysis was 7.85~10.04%, allowing successful foaming process for production of foamed glass. Using Na as the modifying agent of glass was effective in the hydrolysis by water. The highest water content of hydrated glass was obtained when weight ratio of NaOH to the glass was 0.04.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.7
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• pp.3327-3333
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• 2011

The interest on the recovery of thermal energy using the industrial waste has been rising to solve the problems of continuous increase of waste generation and the depletion of the fossil fuel recently. To recovery from the waste among the new recyclable energies has been proved as the most favorable when the potential value of energy source is compared. The RDF made from the industrial waste has been approved as the most economical method. This research has analyzed the heavy metal components containing in the industrial waste. The concentration of Cl and S in the industrial waste generated in C-industrial complex are slightly high than that of the B- and A-industrial complex. The main components generated from A-industrial complex, B-industrial complex, and C-industrial complex are alumina-silicates, calcium alumina silicates, and the mixture of lime and calcium alumina silicate. These results could be used to reveal the origin of inorganic components in industrial waste and utilized as a basic data to improve the performance of the RDF as fuel.

• Geotechnical Engineering
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• v.13 no.1
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• pp.59-74
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• 1997

This paper presents the results of the geotechnical investigation and settlement analysis of a finished waste landfill to find the possibility of the site as a construction area. Also, the variations of the strength of the municipal waste after mixing with the several types of the particulate grouts are investigated. The materials of the grouts used in the experiment are Quick Lime, Portland Cement, Slag Cement and Geocrete Cement. The results of the geotechnical investigation show that the maximum dry unit weight of the waste becomes lower and optimum moisture content higher as the age of the disposed waste is younger and the organic content is higher. The thickness of the predicted differential settlements of the waste fill has large difference from location to location and the unconfined compression strength of the grout mixed waste from the experiment was higher in the order of Geocrete Cement, Slag Cement, Portland Cement and Quick Lime.