• Journal of the Korean Ceramic Society
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• v.13 no.3
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• pp.21-27
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• 1976

Foam formation of Slag-Quartz-$\textrm{Na}_2\textrm{CO}_3$ system was investigated. The foaming agent used was sulphide and sulphate compounds which are present in the slag. The microstructures and x-ray analysis of foam slag, the effect of composition and particle size of slag on the formation temperature, and foam size and distribution of slag foam were studied. The Increment of $\textrm{Na}_2\textrm{O}$ in the slag batch composition decrease the initial foam formation temperature and enhance the foam growth. The formation of temperature and soaking time had pronounced effect on the foam growth and increasing the glass phase in the slag foam.

• Journal of the Korean Ceramic Society
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• v.15 no.4
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• pp.185-192
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• 1978

The effects of slag prticle size, $Na_2SO_4$ addition and sulphide in slag to the foam formation was investigated. This investigation showed that the slag particle size and the amount of $Na_2O$ had produced effects on the size of the foam, foam distribution and firing temperatures. In addition to that the amount of sulphide loss during the firing was controlling factor for the foam formation. The smaller slag particles and higher firing temperatures increased the loss of sulphide in the slag. The addition of $Na_2SO_4$ in the slag batch was likely to inhibit the foam formation. The larger slag particles resutled in the larger foam size and tended to be increasing the batch firing temperature. The main constituents of slag formed glass consisted of wallstonite and glassy phase. It is believed that the controlling the slag particle size and the amount of $Na_2SO_4$ in the slag batch will probably be main factors in foam formation.

• Journal of the Korean Ceramic Society
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• v.14 no.4
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• pp.248-255
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• 1977

The effect of firing temperature, soaking time and batch composition upon the glass phase and pore formation as well as their distribution in slag foamed glass was investigated. Sulfur dioxide gas produced by the oxidation and reduction of metal sulfide in waterslag was attributed to foam forming agent. Slag foamed glass matrix was mainly composed of 35~60% glas phase and melilite crystalline phase. The increment of bentonite addition in batch lowered the foam forming temperature in studied system. The result showed also that the foam size distribution was broadened as th firing temperature wa inbereased.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.132-133
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• 2014

In this study, high volume of industrial by-products including blast furnace slag, recycled aggregate powder and incineration ash have been utilized on the slurry of the foamed lightweight concrete. As to decrease the price of the lightweight foam concrete, mortar based slurry and concrete based slurry has been fixed. As the variation of the foam conduction ratio and aggregates, the foam ratio and compressive strength has been tested. Results showed that using recycled aggregates in the slurry showed better effect than using natural aggregates due to the alkali properties of the recycled aggregates could activate the potential hydraulic properties of the blast furnace slag. Consider about the low price of the recycled aggregates, it could be identified that using recycled aggregates in high volume blast furnace slag blended lightweight concrete showed better compressive strength than natural aggregates.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.4
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• pp.18-25
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• 2020

The purpose of this study is to investigate the mechanical and carbon-capture properties of foam concrete containing stainless steel argon oxygen decarbonization(AOD) slag. AOD slag was used as a binder, and foam concrete having a foaming ratio of 69 ± 0.5 % and a slurry density of 573.2 to 578.6 kg / ㎥ was produced. In order to examine the effect of carbonation, blended specimen was cured by two types : normal curing and CO₂ curing. As a result of the experiment, the specimens incorporating AOD slag showed higher compressive strength than Plain after CO₂ curing. According to the analysis of the image of foam concrete, it was confirmed that the ST30 has a lower total pore volume and average pore size than plain, resulting in high compressive strength. The SEM analysis confirmed the formation of calcite by carbonation of AOD slag. Through the thermogravimetric analysis, the increase of CO₂ uptake was confirmed by the incorporation of AOD slag. Foam concrete has a higher porosity than normal concrete, so it is expected that carbon-capture performance can be improved by using a AOD slag.

• Resources Recycling
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• v.15 no.2 s.70
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• pp.18-23
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• 2006

Foaming of slag is a thermodynamically unstable phenomenon and has significant effects in iron and steelmaking processes. For better recycling method of pulp sludge, the application as an defoaming agent during steelmaking process was adopted and tested. The forming machine has been modified in order to produce the briquettes, which are made of pulp sludge and slag with different weight ratio. Influencing factors on the foaming phenomena have been studied and tested for better understanding of foaming phenomena. Experiments were carried out with $CaO-FeO-SiO_2$ based slags with Ar gas injection and addition of coke particles. The slag basicity and (%FeO) contents adapted as major factors to treasure foaming tendency of the slag system. It was found that foam index (${\Sigma}$) gradually decreased as both the basicity and the (FeO) content increase. Four kinds of antifoaming agent such as aluminium dross, cokes, rice bran and pulp sludge with steelmaking slag have been tested in actual process. Aluminium dross was the most effective, and pulp sludge with steelmaking slag also showed the desired results.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.31-35
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• 2001

Slopping deteriorates the productivity and the stability of operation in BOF refining process, and hence POSCO has developed methods to predict and prevent slopping. Specific equipment was developed to measure the change of the reacting force to the oxygen-blowing lance against oxygen jet and the force was gathered and analyzed with the flow rate of oxygen and the height of lance. From this study, it was found that the reacting force is strongly correlated to the slag foam height. Currently, the modeling of the relation of the slag foaming level and the vertically acted force to lance is being approached for predicting the slopping.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.77-78
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• 2020

In Korea, more than 30,000 tons of waste Styrofoam are produced every year. Styrofoam is spent more than 500 years decomposing during the reclamation process, so it needs to be recycled. The recycling rate of waste styrofoam continues to be the third highest in the world, but it is lower than that of Germany and Japan. Therefore, measures are needed to increase the recycling rate of waste Styropol. Another problem is that cement is mainly used in existing lightweight foam concrete. However, large amounts of CO2 from cement-producing processes cause environmental pollution. Currently, Korea is increasing its greenhouse gas reduction targets to cope with energy depletion and climate change, and accelerating efforts to identify and implement reduction measures for each sector. In 2013 alone, about 600 million tons of carbon dioxide was generated in the cement industry. Therefore, this study replaces CO2 generation cement with furnace slag fine powder, uses crude steel cement for initial strength development of bubble concrete, and manufactures hardening materials to study its properties using waste styrofoam. As a result of the experiment, the hardening agent replaced by micro powder of furnace slag was less intense and more prone to absorption than cement using ordinary cement. Further experiments on the segmentation and strength replenishment of furnace slag are believed to contribute to the manufacture of environmentally friendly lightweight foam concrete.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.97-106
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• 2009

self-loading, various problems related to construction can be solved as well as the save of construction cost. Thus, this study has an aim of applying foam concrete to structural purpose by adding bottom ash as a reinforcing material like fine aggregate, in contrast to conventional non-structural usage such as soundproofing or insulating materials. In addition, it was evaluated in terms of unit volume weight, flow value, air void, water absorption and dosage of foam agent wether replacement of cement by granulated blast furnace slag or fly-ash has an effect on the material characteristics of foam concrete. As results of experiments, it can be found that the increase of fine aggregate ratio, that is to say, the increase of bottom ash results in the increase of unit volume weight, while decreasing air void and flow value. But, appropriate addition of bottom ash to foam concrete makes it easy to control a homogeneous and uniform quality in foam concrete due to less sensitive to bubbles. As the replacement ratio of mineral admixtures such as granulated blast furnace slag and fly-ash increases, as unit volume weight tends to decrease. In the meanwhile, serious effects were shown on fluidity of foam concrete when more than limit of replacement ratio was applied.

• Journal of the Korea Institute of Building Construction
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• v.17 no.6
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• pp.507-515
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• 2017

This study is to develop a high quality lightweight foamed concrete that can be applied in the field using EXFG by cracking reducing agent combined with FGD and ALS. First, to increase the volume of foam, the flow and density of the mixture was increased and decreased, respectively. At this time, the effect of substitution ratio of EXFG on fluidity was negligible. The fraction of foam was the highest at EXFG 1%, and the settlement was found to be prevented by the expansion reaction at EXFG 1%. At this time, the ratio of foam was 65%. In the compressive strength, the strengths were similar or decreased when the substitution ratio of EXFG was more than 1%. The apparent density satisfied the KS 0.5 type at the bubble contents was 65%. In case of EXFG substitution, dry shrinkage was decreased by about 10%. As the substitution ratio of EXFG increased, the thermal conductivity increased proportionally.