• Journal of the Korea Concrete Institute
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• v.18 no.2 s.92
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• pp.267-274
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• 2006

Greenhouse gas reduction will be highlighted as the most pending question in the cement industry in future because the production of Portland cement not only consumes limestone, clay, coal, and electricity, but also release waste gases such as $CO_2,\;SO_3$, and NOX, which can contribute to the greenhouse effect and acid rain. To meet the increase of cement demand and simultaneously comply with the Kyoto Protocol, cement that gives less $CO_2$ discharge should be urgently developed. This study aims to manufacture non-sintering cement(NSC) by adding phosphogypsum(PG) and waste lime(WL) to granulated blast furnace slag(GBFS) as sulfate and alkali activators. This study also Investigates the hydration reaction of NSC through analysis of scanning electron microscopy(SEM), X-ray diffraction(XRD), differential thermal analysis(DTA), and pH. Results obtained from analysis of the hydrate have shown that the glassy films of GBFS are destroyed by the activation of alkali and sulfate, ions eluted from the inside of GBFS react with PG and produce ettringite, and consequently the remaining component in GBFS slowly produced C-5-H(I) gel. Here, PG is considered not only to play the role of simple activator, but also to work as a binder reacting with GBFS.

• Resources Recycling
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• v.8 no.1
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• pp.29-36
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• 1999

Utilization of iron bearing dusts has been needed agglomeration prior to use as a burden in blast furnace The cold bonded pellet process using iron bearing dusts has been developed as an alternative to the conventional heat indurated pelletizing process. Partial substitution of cements with cheaper materials would decrease the production cost of pellet. This paper discusses the strength of pellet containing blast furnace slag as a bonding material in pelletizing a cold bonded agglomerates. Depending upon the quality, half of the cement required may be replaced by slag in the pellets with a strength of around 150 kgf. Some of the physicochemical properties of the bonding materials are also investigated in the present work.

• Magazine of RCR
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• v.12 no.2
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• pp.26-32
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• 2017

• Resources Recycling
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• v.4 no.1
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• pp.60-68
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• 1995

Iron-bearing dust which stems from steelworks were pelletized and bonded with portland cement in order to attempt to use for blast iurnace burdens. The characterist~cs of cold bonded dust pellet were investigated. It was found that the compression strength of cold bonded pellet contaning portland cement of 10 wt.% reached above 150kg/p by proper curing treatment. Direcl contad of carbon with iron oxides seems to greately enhance a reduction reaction and herewxth increased chances to lorn pores at high temperature environment. Tumbler strength, RDI, and swelling of cold bonded pellet were similiar to and/or better than those of iron ore sinter and fired pellet.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.33-36
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• 2006

This Study is based on manufacture non-sintering cement(NSC) by adding phosphogysum and waste lime to GBFS as sulfate and alkali activators. This study also investigates the basic physical properties and duality of NSC, and evaluates its reusing possibility as construction materials. Therefore, we design 40MPa and 60MPa for compressive strength using OPC and NSC by binder. And There is a purpose to present fundamental data, applying in field and analyzing quality control of concrete using NSC according to rate of replace between OPC and NSC.

• Resources Recycling
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• v.25 no.4
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• pp.23-31
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• 2016

It was found that there was no problem in recycling by-products (waste rock and tailings) from Yangyang iron mine themselves through matter conversion because they are not hazardous according to results of KSLT method. In case of using tailings as sub-materials of cement, it recommended the use of less than 3% tailings dosage not to exceed 0.6% of total alkali ($R_2O$) content based on standard quality of portland cement (KS L 5201). Non sintered eco-brick corresponding to class 1 quality of recycled clay brick (KS I 3013) can replace 15% of cement with tailings and 100% of general fine aggregate with waste rock from iron mine. As mentioned above, recycling the by-products (waste rock and tailings) as sub-materials of cement and non sintered eco-brick could gain both environmental and economic benefits, that is, reduction of scale and maintenance cost of tailing ponds, decrease of energy use and $CO_2$ emission.

• Journal of the Korea Institute of Building Construction
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• v.15 no.1
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• pp.17-23
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• 2015

In this research, the $CO_2$ absorption performance of mortar was investigated. The level of $CO_2$ absorption in mortar with various binders including cement and nonsintered cement was examined. As a result for the mortar with photosynthetic bacteria, the compressive strength was similar to the one without the bacteria at early age but decreased at the age of 28 days. However, for the $CO_2$ absorption, with photosynthetic, the performance of the mortar with OPC, and nonsintered cement deceased to 21%(234 ppm) and 19.7%(243 ppm) respectively after 12 hours age.

• Journal of the Korea Concrete Institute
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• v.27 no.3
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• pp.237-244
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• 2015

Entering the 20th century since the industrial revolution, the cement has been widely used in the field of construction and civil engineering due to the remarkable development of construction industry. However, result from that development, each kind of industrial by-products and waste and the carbon dioxide generated in the process of cement production cause air pollution and environmental damage so earth is getting sick now slowly. Therefore, we have to recognize importance about this. It means that the time taking specific and long-term measures have come. In this research paper, as substitution of the cement generating environmental pollution, we investigate the hydration reaction of non-Sintered Cement mortar mixed with GBFS, active stimulant of alkaline and sulphate series by using SEM and XRD, mechanical and chemical properties according to the curing method. As a result of this experiment, NSC realized outstanding strength for water curing and steam curing. It means that it has a good possibility as substitution of cement. From now on, it can be used for structure satisfying specific standard. We expect to find a substitution of outstanding cement by progressing continuous research making the best use of pros and cons according to the curing method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.309-310
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• 2023

Slag and ash generally have a higher powder degree than portland cement, so workability may deteriorate under the same unit quantity condition, and strength and durability decrease when the unit quantity is increased. At this time, if an aggregate having a low water absorption and an appropriate particle size is used to recover the loss of strength, it can contribute to reducing the unit quantity of the binder. Therefore, for the purpose of improving the workability and strength of non-sintered cement mortar using slag and ash, ferro nikel slag whose particle size was adjusted was used as an aggregate and its applicability was identified. In this experimental condition, it was confirmed that non-sintered cement mortar tends to improve workability and secure strength when ferro nikel slag having various particle size distributions is used as an aggregate. This can be analyzed as the effect of ferro nikel slag material properties including glassy properties and mixing conditions with a wide particle size distribution.

• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.47-53
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• 2010

The purpose of this study was to investigate the effectiveness of a stabilization treatment for As contaminated soil. A combination of hydrated lime, Portland cement, $FeCl_3{\cdot}6H_2O$, and NaOH were used as stabilizing agents. The effectiveness of stabilization treatment was evaluated by the Korean Standard Test (KST) method (1N HCl extraction). Sequential extractions were performed to investigate the As distribution after treatment. Following the application of the treatment, curing periods of up to 7 and 28days were investigated. The experimental results showed that a combination of hydrated lime/Portland cement was more effective than treatments of hydrated lime or Portland cement at immobilizing As in the contaminated soil. The treatment of 25wt% hydrated lime and 5wt% Portland cement was effective in reducing As leachability less than the Korean warning standard of 20 mg/kg. However, the treatments of hydrated lime and Portland cement failed to meet the Korean warning standard even when up to 30 wt% was used. The treatment utilizing hydrated lime and $FeCl_3{\cdot}6H_2O$ was not effective in properly reducing As leachability. The addition of $FeCl_3{\cdot}6H_2O$ was negative in terms of pH condition. Moreover, the treatment with hydrated lime/NaOH was effective in reducing As leachability but not as much as hydrated lime/Portland cement. The sequential extraction results indicated that the residual phase was greatly increased upon the treatment of hydrated lime/Portland cement. It was concluded that the hydrated lime/Portland cement treatment was the best among the other combinations studied at achieving trace As concentrations.