本研究係於高溫熔融(玻璃化)法(操作溫度1450oC、持溫30分鐘下) 中添加助熔劑(白雲石:石灰石:碎玻璃 = 1:3:4重量比),進行廢鎳氫電池金屬(鎳及鐵)之回收,探討不同助熔劑量/進料量比值下之熔融成效與廢鎳氫電池金屬的回收率。研究結果顯示,熔融冷卻後之主要產物為熔渣及金屬錠。熔渣主要成分為鈣、鎂及矽,其主要來自於進料之添加物,所有熔渣均符合毒性溶出試驗(TCLP)之標準,為具有再利用潛力之資材;而金屬錠之主要成分為鎳及鐵,共約佔67~99%,且添加物/廢電池重量比≧3/7時,金屬錠/廢電池重量比可達約70%。大部分的鎳、鐵、鈷、銅及錳被移行至金屬錠,其回收率達90%以上,可供進一步金屬冶煉,故高溫熔融法於廢鎳氫電池金屬(鎳及鐵)之回收上,具有發展之潛力。
This study investigated the recovery of metals from waste NiMH batteries using a thermal melting (vitrification) process (at 1450oC for 30 min) with/without the addition of melting-aid (dolomite:limestone:cullet = 1:3:4 w/w) and explored the mass ratios of recovered metals to fed battery at various weight ratios of additive to fed battery. The results show that the main products of vitrification were slag and ingot. The major components of slags were Ca, Mg, and Si, mainly from the additives, and all slags, in compliance with the limits of TCLP (Toxicity Characteristic LeachingProcedure) in Taiwan, were candidate materials for recycling purposes. On the other hand, the dominant components of ingots were Ni and Fe, accounting for 67–99% weight in ingots. When the mass ratios of additive/battery were ≥3/7, the mass ratios of ingot/battery reached ~70% after vitrification; moreover, most of Ni, Fe, Co, Cu, and Mn moved into ingots, and their recoveries were over 90%. The ingots can be further treated in smelters. Therefore, the vitrification process has a good potential to be applied for recovering metals from waste NiMH batteries.