隨著時代的進步，鋼鐵需求量逐年上升，因此CO2的排放量也隨之上升；隨著溫室效應越來越嚴重以及環保意識的抬頭，鋼鐵業在CO2排放量上佔了很大的比例，自然首當其衝，面臨挑戰，也因此漸漸的各大鋼鐵業者紛紛轉向低碳煉鋼方面相關研究，另外，由於高品質煤礦含量的急速縮減，造成成本逐年上升，因此尋找一替代品亦是迫在眉睫的課題。

本研究利用椰殼炭取代焦炭做為還原劑，以非高爐煉鐵中的旋轉床爐製程(Rotary Hearth Furnace, RHF)將其煉製成直接還原鐵(Direct Reduced Iron, DRI)後，並以不同配比與製程參數進行實驗，討論在不同參數下壓碎強度與金屬化率的關係。而DRI後續可做為高爐金屬加料進而增加鐵水產量或是其他用途。

實驗結果發現，在固定反應條件下，壓碎強度會隨著碳氧摩爾比[(C/O)mol]的增加而上升，另外，當黏結劑的添加量上升時，壓碎強度也會大幅度的提升，當添加量達2.5wt%時，已達投入高爐之最低標準；而延長反應時間與提升反應溫度也都可讓(C/O)mol = 0.8這組的壓碎強度達到所需要求，(C/O)mol = 1這一配比則無法藉由參數調整達到所需之壓碎強度；另外，保護氣氛流量對於壓碎強度的影響於本實驗中的結果發現是幾乎沒有影響的。

而在金屬化率方面，本研究之金屬化率並未如文獻般隨著(C/O)mol增加而上升，其數值呈現一較不規則分布；而黏結劑的添加量則對金屬化率影響不大；反應溫度與反應時間所得之結果也並未如預期結果獲得大幅度提升；而在保護氣氛流量方面，藉由保護氣氛流量的提升，減少再氧化現象的產生，對於(C/O)mol=1這組的金屬化率有約10%的提升；本實驗中之金屬化率均不如預期，原因有數項，但最後歸納其可能原因為分析時，樣品處理方式所造成。

Due to the generational improvements, the demand for iron and steel has increased year after year. CO2 emission quantity has also risen along with this demand. With the greenhouse effect getting worse and consciousness about environmental protection becoming a serious consideration, the traditional iron and steel manufacturing industry faces a tremendous challenge owing to its huge contribution in the world’s CO2 emission. Therefore, in order to solve this problem, many iron and steel manufacture companies have searched for method to reduce carbon emission. In addition, the quantity of high-quality metallurgical coal has decreased and has become more expensive. In order to solve the problem of carbon emission and reduction of metallurgical coal, biomass charcoal was utilized to replace coke or coal as a reductant in recent years.

In this investigation, coconut charcoal was used to replace coke as reductant, by simulating RHF process to produced direct reduced iron ( DRI ). For DRI, the primary purpose in ironmaking is added to blast furnace as a metallic feed which the strength and degree of metallization was restricted. Thus, different ratios of raw materials as well as process parameters were used to conduct the experiment and the relationships among the parameters, crushing strength and the degree of metallization were discussed.

The results indicated that under fixed reaction conditions, crushing strength decreased while (C/O)mol increased due to the morphological shape and content of residual carbon. On the contrary, strength increased with addition of bentonite. As the addition of bentonite reaching 2.5 mass%, crushing strength achieve the lowest standard of metallic feed of blast furnace(0.6kg/mm2). For raising reaction time and temperature, crushing strength increased significantly when (C/O)mol was 0.8. However, crushing strength hardly varied when (C/O)mol was 1 with promotion of reduction time and temperature. Additionally, the protective atmosphere flow rate have extremely tiny effect on crushing strength in this investigation.

The results of metallization degree were not the same as the literature on this topic has suggested, (an increase in (C/O)mol). In this study, the degree of metallization was a disorder distribution with raising (C/O)mol, and the addition of bentonite had a slightly effect on metallization degree. Besides, the results by extending reaction time and promoting temperature didn’t increase substantially as we expect. But, the degree of metallization could have 10% increment due to decreasing re-oxidation by raising the flow rate of protective atmosphere when (C/O)mol was 1. All the value of metallization degree in this investigation were not as high as those reference we mentioned in this study. The most probable reason which caused the low degree of metallization was the method of dealing sample before chemical composition analysis.

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