• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.2
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• pp.20-27
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• 2019

Compared to the development and manufacturing technology of electronic goods, the development of waste glass recycling technology is relatively insufficient, leading to the acceleration of waste of resources and environmental pollution. Although waste glass recycling technology is being actively developed overseas, waste glass recycling technology is insufficient in Korea, leading to the illegal dumping or burial of waste glass. Waste glass has been confirmed to have pozzolan reaction potential when having hydration reaction with cement. Waste glass is also reported to be effective in reducing bleeding and inhibiting the development of hydration heat by improving the physical properties of concrete and the rheology properties of fresh concrete. Therefore, this paper analyzed the strength characteristics and the effect of alkalic-silica reaction on the expansion of shielding concrete that used waste glass as fine aggregate. Where, suitable admixture materials were used as a measure to suppress the expansion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.67-71
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• 2008

Blast Furnace slag a pigiron waste that is produced more than 800 thousand tons per year, and micronized double quenching blast furnace slag improves flexibility of concrete, and even shows improvement effect of long-term intensity. However, the concrete that used micronized double quenching blast furnace slag is restricted in its use because of many problems to assure early intensity. Even micronized blast furnace slag can assure its early intensity of concrete when maximizing, and is considered that can be applied in high strength of blast furnace slag as an alternation material for Silica-fume that depends on overall import. Hereby this paper is revised activity index and fluidity of mortar that used Nano Slag that is produced by rotten Nano crush equipment to propose its size, and possible utility of Nano Slag that was produced by blast furnace slag made in Korea as an alternation material, with the conclusion as following. 1. To measure micronized Nano slag, it is judged that it should be in progress with BET method that is based on micronized Silica-fume for concrete. 2. As a result, the test based on KS L ISO 679 is shown to satisfy the basic additive size of KS F 2563 and of KS F 2567, and to determine new combination of stipulations. 3. The strength development of Nano Slag was shown excellent in the daily initial installment of 1, 3, 7 days against the basic additive. This is judged that contains CaO controlling initial strength against Silica-fume, and contributes to higher fineness than the basic blast furnace slag 1 type.

• Computers and Concrete
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• v.32 no.4
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• pp.373-381
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• 2023

Fly ash, granulated blast furnace slag, marble waste powder, etc. are just some of the by-products of other sectors that the construction industry is looking to include into the many types of concrete they produce. This research seeks to use surrogate machine learning methods to forecast the compressive strength of self-compacting concrete. The surrogate models were developed using Gradient Boosting Machine (GBM), Support Vector Machine (SVM), Random Forest (RF), and Gaussian Process Regression (GPR) techniques. Compressive strength is used as the output variable, with nano silica content, cement content, coarse aggregate content, fine aggregate content, superplasticizer, curing duration, and water-binder ratio as input variables. Of the four models, GBM had the highest accuracy in determining the compressive strength of SCC. The concrete's compressive strength is worst predicted by GPR. Compressive strength of SCC with nano silica is found to be most affected by curing time and least by fine aggregate.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.4
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• pp.38-44
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• 2010

Foundry sands are made up of silica and some coking agents, such as bentonite or resin, and used as templates for the production of various casting products. Foundry sands, which are repeatedly used, were finally transformed into the waste materials by heat, losing their proper functions. The used foundry sands have been treated as general wastes according to the contents of coking agents used. Silica, however, can be recycled through the proper treatment due to its physical property not to changed by heat. In this study, we have identified and investigated at the occurrence, treatment and recycling status of the used foundry sands, as well as for the regime and inhibitory factors of the recycling of them in domestic and foreign cases.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.195-196
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• 2023

In this study, the mechanical properties, alkali-silica reaction(ASR) expansion and residual mechanical properties after ASR of waste glass fine aggregate(GS) mortar according to mineral mixture were evaluated. As a result, it was found that the mineral mixture reduces the ASR expansion. However, mechanical properties and residual mechanical properties have decreased.

• Journal of Animal Environmental Science
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• v.1 no.1
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• pp.77-82
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• 1995

In order to investigate the purification effects of livestock waste water, Modified Activated-Sludge Process(MASP) containing marine silica and volcanic ash-rock as the contact media and Sawdust-Soil Filter Method were used. The results obtained are as follows: 1. MASP which treated two metric tons' livestock waste water a day decreased BOD by 97.5% from 4,400.0mg/I to 108.8mg/I and SS by 98.0% from 5,335.0mg/I to 111.0mg/I. 2. MASP decreased BOD by 93.9% from 2,549.1mg/I to 156.6mg/I and SS by 96.3% from 3,521.9mg/I to 132.0mg/I when ten metric ton's livestock waste water was treated a day. 3. BOD and SS were decreased by 83.4% from 45.1mg/I to 7.5mg/I and by 83.4% from 47.5mg/I to 7.9mg/I when the supernatant layer treated by MASP was purified by Sawdust-Soil Filter Method.

• Resources Recycling
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• v.16 no.2 s.76
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• pp.48-55
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• 2007

A low-priced catalyst for pyrolysis of LDPE has been synthesized. Fly ash, which is waste material generated from coal-fired power plants was used as silica and alumna sources for solid acid catalyst. Amorphous silica-alumina catalysts (FSAs) were pre-pared by dissolution of silica and alumina from fly ash, followed by co-precipitation of the dissoluted ions. A series of LDPE pyrolysis were carried out in a thermogravimetric analyzer to investigate the effects of synthesis conditions such as NaOH/fly ash weight ratio and activation time one catalytic performance of FSAs. The physical properties of FSAs were examined and related to their catalytic performances. FSA(1.2-8) synthesized with NaOH/fly ash weight ratio of 1.2 and the activation time of 8 hours showed the best catalytic performance. The catalytic performance of FSA(1.2-8) was comparable with that of commercial catalysts and it was concluded that the FSA could be a good candidate for catalytic use in the recycling of waste polyolefins.

• Journal of the Korean Professional Engineers Association
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• v.34 no.2
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• pp.167-173
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• 2001

Through alkaline hydrothermal activation processes, Na-A type zeolite was synthesized as a single phase withfunnel-glass waste from a television tube factory. The autoclaving was performed in a closed teflon vessel in therange of 80~95"C. The silica-rich solution as a starting material was hydrothermally synthesized with quartz in INNaOH by heating 350"C under the pressure of 1,500 atm. NaA102 was made from NaOH and Al(OH)3 by heating95"c for 2~3 hours and the molar ratios of it were Na20/A1203=1.4 and H20Ha20=8. The equi-dimensional Atype zeolite (1 ~2 U) was formed by the simple mixing of'the silica-rich solution, glass waste and NaA102 for I~3hours-heating at 80"C. The characterization of the reaction product shows Na-A as a single phase. The synthesizedzeolite has cube-dodecahedral form and Ca2+ ion exchange capacity of the Na-A was in the range of 215~220mequivalent/100 g.20mequivalent/100 g.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.320-325
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• 2012

The catalytic cracking of waste lubricant oil was carried out on silica-alumina (SA), hydrogen-type mordenite (HM), and dealuminated mordenite (DM) with the silica/alumina ratio of 10.5, 10, and 12.5, respectively. Activity in the catalytic cracking was found to be in the order of SA > DM > HM. Carbon number distribution of the oil obtained over SA was similar to that of gasoline while that of the oil obtained over DM was similar to that of diesel. Carbon number distribution of the oil obtained over HM was similar to that between gasoline and diesel. Acid amounts of three kinds of catalysts were found to be in the order of $SA\;{\approx}\;HM$ > DM. Unlike HM and DM with pores of an uniform diameter below 10 A, SA had a pore size distribution within the range of 10 to 50 A. These results indicate that the acid amount and pore size of the catalysts may be related to the carbon number distribution of the cracked oil. The decrement of surface area by the accumulation of carbon and impurities on the surface of the catalyst was found to be in the order of SA > DM > HM.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.1
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• pp.88-94
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• 2011

To make recycling aggregate, quantity of fine particles increase due to multi-crushing. Though this particles were mixed with recycling aggregate, those have to be disparted from aggregate in the high quality recycling aggregate, because of the cause of low quality. Considering reactivity, fine particles is better than coarse one. Therefore, it needs to develop suitable usage. We try to make cement extruding material by using the fine particles from concrete recycling, as a silicious replacement. Test results are as follows ; 1) Waste concrete powder has major ingredients such as $SiO_2$ and CaO, its density is $2.45g/cm^3$ being similar to silica powder, its diameter is range 13 to $141{\mu}m$. 2) Considering to strength properties according to particle size, specimen was made using small particles is higher strength than large one. 3) Despite of exception in the autoclaved curing, when the replacement of waste fine particle increase, strength of extruding panel shows almost same level.