本文選題：銅尾礦 + 黑曲霉�。� 參考：《南華大學(xué)》2015年碩士論文

【摘要】：尾礦中含有大量的可利用金屬。從尾礦中提取有價(jià)金屬,對(duì)減少尾礦中重金屬對(duì)環(huán)境的影響及提高資源的二次利用具有重要意義。本文旨在研發(fā)一種銅尾礦的生物浸出方法。以湖南某高堿性氧化銅尾礦為研究對(duì)象,研究了黑曲霉發(fā)酵液浸出和黑曲霉直接浸出兩種浸出體系下的銅尾礦浸出行為,取得的研究成果如下:首先,開展了黑曲霉發(fā)酵液浸出實(shí)驗(yàn),研究了溫度、馬鈴薯-蔗糖含量、接種量和發(fā)酵時(shí)間對(duì)發(fā)酵液中黑曲霉菌絲球形態(tài)的影響,并利用不同菌絲球形態(tài)的發(fā)酵液浸出銅尾礦。結(jié)果表明:菌絲球直徑越小,銅的浸出率越大。在溫度30℃,接種量0.8%(OD600=0.1),馬鈴薯-蔗糖含量30%,發(fā)酵時(shí)間65 h的條件下,形成的菌絲球直徑最小,數(shù)量最多。利用此條件下的發(fā)酵液在30℃,180 r·min-1條件下浸出3 d,銅的浸出率可達(dá)到83.25%。其次,進(jìn)行了黑曲霉直接浸出銅尾礦實(shí)驗(yàn),研究了培養(yǎng)時(shí)間、培養(yǎng)基成分、接種量、溫度、轉(zhuǎn)速和礦漿濃度等因素對(duì)黑曲霉的菌絲形態(tài)以及銅浸出的影響。結(jié)果表明:黑曲霉-銅尾礦菌絲球的形成可降低浸出液的粘度,提高浸出率。當(dāng)培養(yǎng)時(shí)間為7 d,培養(yǎng)基中蔗糖含量為20 g·L-1,接種量為0.02%(OD600=1.0),培養(yǎng)溫度為25℃,搖床轉(zhuǎn)速為180 r·min-1和礦漿濃度為5%(v/w)時(shí),形成的黑曲霉-銅尾礦菌絲球粒徑小,個(gè)數(shù)多,且此條件下,銅的浸出率達(dá)到最大為89.45%。最后,研究了黑曲霉-銅尾礦菌絲球的結(jié)構(gòu)和形成過程。結(jié)果表明,黑曲霉與銅尾礦共同培養(yǎng)時(shí)黑曲霉-銅尾礦菌絲球的形成分為三個(gè)階段:黑曲霉孢子發(fā)芽形成菌絲;形成的菌絲在外力作用下以晶核為中心向外延伸生長,包裹銅尾礦形成黑曲霉-銅尾礦菌絲球;培養(yǎng)基內(nèi)營養(yǎng)成分變化,菌絲球自溶。黑曲霉-銅尾礦菌絲球的結(jié)構(gòu)為三層,外層為黑曲霉菌絲、中間為銅尾礦、內(nèi)部為空殼的核-殼結(jié)構(gòu)。
[Abstract]:The tailings contain a large amount of available metals. The extraction of valuable metals from tailings is of great significance in reducing the environmental impact of heavy metals in tailings and improving the secondary utilization of resources. This paper aims to develop a bioleaching method for copper tailings. Taking a high alkaline copper oxide tailings in Hunan as the research object, the leaching behavior of copper tailings in two leaching systems of Aspergillus Niger fermentation liquid and Aspergillus Niger was studied. The results are as follows: first, The effects of temperature, potato sucrose content, inoculation amount and fermentation time on the morphology of Aspergillus Niger hyphal ball were studied. The results showed that the smaller the diameter of hyphae ball, the greater the leaching rate of copper. Under the conditions of temperature 30 鈩，

本文編號(hào)：1927447