台灣電弧爐煉鋼業之鋼鐵產量，幾乎每年以正成長速度上升，生產每公噸鋼鐵約有10-20公斤煉鋼煙塵，由此推估台灣電弧煙煉鋼煙塵年發生量約有8~16萬公噸。由於電弧爐煉鋼煙塵顆粒微細，易造成環境問題，又因富含具經濟價值之重金屬，在世界各國皆受到重視。
目前回收煉鋼煙塵中有價金屬以Wealz process為主流，煙塵含有過高的氯，於後續金屬回收處理將會造成戴奧辛(Dioxin)產生及高溫管線腐蝕之問題。此外，回收Zinc Oxide如含氯量過多，會使經濟價值偏低。以台灣為例，因廢鋼鐵來源不穩定又為避免石灰粉化添加NaCl使得煙塵含氯量甚至高達10%，較其他國家來得高。
本研究目的在於濕法除氯之可行性，並探討在風化過程中Fe、Zn、Pb之溶出行為及結晶相之轉換。研究結果顯示，濕法除氯約可去除75%含氯量，風化對於除氯並無顯著變化。由於風化過程中產生HCl使得煙塵pH值下降至8.5-9，促使Fe、Pb及Zn穩定，有利於後續重金屬之回收。且實驗中發現，含Pb煙塵於長時間風化後，將產生 Pb(OH)Cl及Pb3(CO3)2(OH)2。

In comparison with other countries, electric arc furnace dust (EAF dust) contains high chlorine content in Taiwan that yield plenty of halogen-bearing dust leading to dioxin emission problem and degraded zinc oxide value during Waelz Kiln Process. The aim of this research work was to investigate the feasibility of dechlorination of EAF dust by water leaching at ambient temperature in laboratory-scale. The effects of aging under weathering conditions upon phase transformation and leaching behavior of heavy metals such as Pb, Zn and Fe are also discussed. The results indicated that water leaching process can remove chlorine effectively. Total chlorine content in EAF dust decreased from 6.98% to 1.75% within 1.5 hr, corresponding to 75% removing efficiency. Aging time has no significant effect on chlorine extraction. According to the aging experiments, some important reactions of lead compounds transformation have been revealed. Laurionite (Pb(OH)Cl) and hydrocerussite (Pb3(CO3)2(OH)2) phases can be present under certain circumstances.

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