浮選分離囘收酸性廢水中和産物之研究

Study on recovery and separation of the neutralization products from acidic wastewater by flotation

蔡敏行(Tasi Min-Shing) ； 林素貞(Lin Sue-Jane) ； 李哲元(Lee Jeh-Yang)

《鑛冶：中國鑛冶工程學會會刊》 32卷2期 (1988/06) Pp. 109-119

https://doi.org/10.30069/MM.198806_32(2).0011

摘要

酸性廢水通常以碳酸鈣等中和劑處理之，因此產生數量龐大的中和汚泥，而此類汚泥主要由石膏與一些金屬沉澱物所構成，是一種貴重之資源，應積極研究其分離囘收，以資利用。本研究就模擬廢水與金瓜石坑内排水之處理，利用碳酸鈣中和，檢討其中和過程，沉降物之沉降特性與表面性質，並進行浮選分離。中和產物靜置24小時後，以捕收劑DAA、抑制劑澱粉之添加，可得石膏品位90％與氫氧化鐵品位87%之浮選分離結果。金瓜石之坑内排水，可由碳酸鈣之分別沉澱處理，得高純度之石膏與氫氧化鐵，而其處理水可達排放水之標準。由分別沉澱－浮選分離之流程，可將中和汚泥分離為有用之石膏與氫氧化鐵，不但直接解決汚泥的處置問題，更可將之化為有用之資源。

並列摘要

Acidic drainage is usually neutralized with calcium carbonate which reduces the acidity of wastewater. The neutralization process produces large amounts of sluge that mainly consists of gypsum and some metal-containing precipiates, thereby making the sluge a valuable resources. Therefore it is worthwhile to study and develop a method of separation and recovery of these materials, so that they can be reused. The objective of this study is to simulate wastewater and mine drainage in the Chinkuashih Mine. First the wastewater was neutralized with calcium carbonate. After the neutralization process, the settling and surface characteristics of the neutralized product were examined under microscope and separated by flotation. After 24 hours, the neutralized precipitates were transferred to the flotation cell and then dodecylamine acetate (DAA) was used as a collector with starch as an inhibitor. The resulting grades of gypsum and ferric hydroxide approximately 90% and 87% respectively. The mine drainage in Chinkuashih can be neutralized with calcium carbonate by selective precipitation. Therefore, it is possible to obtain high grade gypsum and ferric hydroxide from this process. The treated water can also meet the effluent standards. According to the results of the present study, gypsum and ferric hydroxide can be separated and recovered from the neutralized product by a selective precipitation-flotation process. It can solve the disposal problem of sluge and change the sluge into valuable resources.