STUDY OF CaO AND NaCl ADDITION EFFECT ON IRON NUGGET RECOVERY IN COMPOSITE BRIQUETTE IRON SAND CONCENTRATE REDUCTION USING ISOTHERMAL-GRADIENT TEMPERATURE METHOD

• Main Author: DAU SEPTIANINGRUM (NIM : 12513013), ELSA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/21931
• Institution: Institut Teknologi Bandung

Iron steel industry is one of industries that play an important role in supporting economy in Indonesia.The massive infrastructure development projects by government causes increasing of national steel demand. This increase is not balanced with the production capacity of the national steel industry, so the government must import steel. Meanwhile, abundant iron sand resources have not been fully utilized as an alternative raw material of steel making. These problems can be solved by iron sand reduction research. The iron sand reduction study has been done with isothermal-gradient temperature method but still needs to be developed. Therefore, this study determine the effect of CaO and NaCl on iron nugget recovery by the same method. <br /> <br /> <br /> <br /> <br /> A series of experiments were performed with variations in the addition of CaO and NaCl. The experiment started with preparation of iron sand concentrate, coal, CaO, and NaCl. Initial characterization was carried out on iron sand concentrate by X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF), while coal was characterized by proximate test and ash content test. The mixture of raw material is agglomerated into briquette composite with variation of CaO and NaCl is 0%; 0.5%; 1%; 1.5%; 2%; 2.5%; 5%; 7.5%; and 10%. Furthermore, the composite briquette was reduced by isothermal-gradient temperature method. The reduction process was started isothermally at 1000 ° C for 30 minutes and then temperature was increased to 1380 ° C for 57 minutes. The last step is isothermal reduction at 1380&#61616;C for 40 minutes. Iron nugget as reduction product were measured by weight and diameter. In addition, microstructural analysis, Scanning Electron Microscope-Energy Dispersive Spectrometer (SEM-EDS), and XRD were performed on the reduction product. <br /> <br /> <br /> <br /> <br /> The results showed that the addition of CaO and NaCl can affect the recovery of iron nugget. The highest percentage of iron nugget was obtained by addition of 0.5% CaO and 2.5% NaCl that is 66.04% and 59.70%. Iron nugget was produced by addition of 0-5% CaO and 0-5% NaCl. The number of iron nuggets tends to decrease along with the increased percentage of CaO and NaCl addition. The average diameter and the maximum diameter of iron nugget increase instead of the less number of iron nugget. The largest average diameter and maximum diameter iron nugget was obtained by addition of 5% NaCl that is 2.2 mm and 5.88 mm. Addition of 0.5% CaO and 2.5% NaCl can break bond between wustite (FeO) and impurity oxide. This is indicated by the absence of titanomagnetite (Fe2TiO4), hercynite (FeAl2O4), and fayalite (Fe2SiO4) in slags. <br />