共查询到19条相似文献,搜索用时 46 毫秒
1.
针对湿法炼锌过程中稀散金属锗的浸出,以含锗氧化锌烟尘为原料,研究了采用常压富氧浸出技术从含锗氧化锌烟尘中回收锌和锗。通过氧化锌烟尘的XRD、SEM-EDS等分析,表明富锗氧化锌烟尘中除含有氧化锌烟尘外,还含有少量硫化锌与硫化铅,部分硫化锌与氧化锌混合形成致密颗粒。考察了铜离子浓度、时间、液固比、温度、氧压等因素对氧化锌烟尘浸出锌、锗的影响。结果表明,在常压富氧条件下,温度90 ℃、液固比7 mL/g时,采用二段浸出4 h,锌、锗的浸出率可超过90%;浸出渣主要物相为硫酸铅以及硫化锌。采用氧化锌烟尘做中和剂对酸浸溶液进行中和还原处理,控制溶液pH值为3~3.5,反应1 h,可将溶液中Fe3+浓度控制在0.02 g/L内,且该过程Ge不发生水解损失,有利于后续溶液中锗的高效分离。 相似文献
2.
提出了微波碱性焙烧—水溶含锗氧化锌烟尘的新工艺,研究了配碱比、熟化时间、微波焙烧温度、液固比、水溶温度等对锗浸出率的影响规律。结果表明:在配碱比1 g·g-1、熟化时间5 d、微波焙烧温度400 ℃、保温时间10 min、液固比5 mL/g和水溶温度70 ℃时,锗的最佳浸出率为91.15%,与现有的常规碱性焙烧含锗氧化锌烟尘工艺对比可知,碱性焙烧温度从950~1 100 ℃降低至400 ℃,碱性焙烧保温时间由1~4 h降低至10 min,锗浸出率由80.35%提高至91.15%。 相似文献
3.
4.
5.
锌冶炼烟尘中锗的富集及锌的回收 总被引:1,自引:0,他引:1
针对硫酸浸出一丹宁沉锗方法存在回收率低、丹宁消耗量大等问题,采用氯化铵焙烧法富集了广西某厂含锗氧化锌烟尘中的锗,并通过直接用水浸取焙烧渣的方法成功回收了锌。试验结果表明,在氯化铵用量为烟尘质量的1、2倍、氯化反应温度为500℃、氯化反应时间为1h的优化条件下,Ge的挥发率可高达95、30%,而锌的浸出率也达到了84.80%。此法成功富集了锗,同时浸出的粗锌通过进一步除杂可回收制备碱式碳酸锌,整个流程中锌的直收率为82.70%。 相似文献
6.
7.
某锡烟尘含Sn 37.43%、Zn 8.82%、In 0.56%,具有较高的综合回收价值。采用硫酸熟化—常压浸出工艺回收烟尘中的有价金属铟、锌,而锡有效富集在渣中。通过条件试验确定适宜的工艺参数为熟化温度140℃,熟化保温时间40 min,硫酸与锡烟尘质量比0.7∶1,浸出时间1.5 h,浸出温度90℃,浸出液固比4∶1 m L/g。在此条件下,铟和锌的平均浸出率分别达到96.68%和97.70%,锡的平均浸出率降低到0.52%。与常压酸浸提取工艺相比,硫酸熟化常压浸出工艺可显著提高铟和锌的浸出率,并显著降低锡的浸出率,实现了铟、锌与锡的高效分离。 相似文献
8.
对铅冶炼难处理复杂氧化锌烟尘碱洗渣进行了"中性浸出—酸浸"工艺试验研究。结果表明,碱洗渣中性浸出时,锌、镉的浸出率先随浸出温度、液固比、搅拌速度和时间的增加而提高,后增速变缓;中浸渣酸浸时,液固比对锌、铟的浸出率无明显影响。锌、铟的浸出率随初始酸度、浸出温度和时间的增加先增加后变缓。中性浸出最佳条件为:温度338K、液固比5∶1、搅拌速度400r/min、浸出时间1h,此条件下,锌、镉的浸出率分别为80.3%和76.3%。中浸渣酸浸最佳条件为:初始酸度100g/L、浸出时间2h、浸出温度363K、液固比5∶1,在该条件下,锌、铟的浸出率分别为97.1%和85.5%。 相似文献
9.
10.
钢铁厂冶炼过程产生的含锌固体废弃物经烟化挥发得到氧化锌烟尘,具有来源广、成分复杂、原料波动性大的特点。以该氧化锌烟尘为研究对象,针对现行湿法炼锌常规工艺处理流程存在原料适应性差,锌直收率低,浸出渣中铅难以富集的问题,本文研究了氧化中浸-加压酸浸组合技术工艺,考察了液固比、反应时间、浸出温度、氧化剂等因素对锌、铟及主要金属离子浸出的影响。结果表明,采用氧化中浸技术在温度60 ℃、液固比3.9 mL/g、中浸1 h、中和2 h、过氧化氢用量62 mL/kg的条件下,锌浸出率达到80%以上,中浸液中铁含量<20 mg/L,可实现锌的浸出与铁的同步沉淀;中浸渣采用加压酸浸技术,利用氧化中浸渣中沉淀的三价铁对硫化物进行氧化浸出,在不添加氧化剂、温度125 ℃、液固比2.5 mL/g、浸出时间3 h,浸出剂酸浓度为150 g/L的条件下,锌和铟浸出率分别达98%和90%以上,锌与铟可同时高效浸出,且可同步实现浸出液中铁价态的控制,加压酸浸液中铁浓度在17 g/L左右、其中二价铁浓度在16 g/L左右,90%以上的铁为二价铁,易于后续溶液处理,加压酸浸渣铅含量≥30%,富集比高。该工艺解决了常规工艺锌直收率低的问题,简化了工艺流程,提高了原料适应性,实现了氧化锌烟尘的高效综合利用。 相似文献
11.
根据生产实际情况及面临的现状,分析锗在烟化炉烟尘—多膛炉—酸性浸出过程中形为变化,根据锗的形为变化过程中来控制锗的存在形态,进而控制锗在酸性浸出过程中的存在形态,提高锗的浸出率。 相似文献
12.
以韶关冶炼厂真空炉渣氧压浸出液为原料,以P204及Rex t-32为萃取剂萃取分离与富集锗组分,考察萃取有机相组成、酸度pH、萃取时间、相比等因素,对锗分离与富集效果的影响.研究结果表明:pH=2.0,相比V (O)/V (W)=1∶1,萃取10 min ,一次萃取锗萃取率达96.89,;富锗有机相用4mol/L氢氧化钠溶液反萃锗,相比V (O )/V (W )=3∶1,反萃15 min ,经3级反萃后反萃液中锗含量为7.81 g/L,反萃率为95.37,(以渣计);锗反萃液用1∶1硫酸中和,控制终点pH为8.0~8.5,可得到品位为37.62,的富锗料,锗沉淀率为90.51,. 相似文献
13.
14.
15.
16.
17.
《Minerals Engineering》2007,20(9):956-958
Metallic zinc production from sulfide zinc ore is comprised by the stages of ore concentration, roasting, leaching, liquor purification, electrolysis and melting. During the leaching stage with sulfuric acid, other metals present in the ore in addition to zinc are also leached. The sulfuric liquor obtained in the leaching step is purified through impurities cementation. This step produces a residue with a high content of zinc, cadmium and copper, in addition to lead, cobalt and nickel. This paper describes the study of selective dissolution of zinc and cadmium present in the residue, followed by the segregation of those metals by cementation. The actual sulfuric solution, depleted from the electrolysis stage of metallic zinc production, was used as leaching agent. Once the leaching process variables were optimized, a liquor containing 141 g/L Zn, 53 g/L Cd, 0.002 g/L Cu, 0.01 g/L Co and 0.003 g/L Ni was obtained from a residue containing 30 wt.% Zn, 26 wt.% Cd, 7 wt.% Cu, 0.35 wt.% Co and 0.32 wt.% Ni. The residue mass reduction exceeded 80 wt.%. Cementation studies investigated the influence of temperature, reaction time, zinc concentration in feeding solution, pH of feeding solution and metallic zinc excess. After that such variables were optimized, more than 99.9% of cadmium present in liquor was recovered in the form of metallic cadmium with 97 wt.% purity. A filtrate (ZnSO4 solution) containing 150 g/L Zn and 0.005 g/L Cd capable of feeding the electrolysis zinc stage was also obtained. 相似文献
18.
19.
《Minerals Engineering》2006,19(5):478-485
Electric arc furnaces (EAF) generate about 10–20 kg of dust per metric ton of steel, which constitute a hazardous waste, known as EAF dust. This dust contains a remarkable amount of non-ferrous metals, which include zinc, cadmium, lead, chromium and nickel that could be recovered, reducing the environmental impact of the leachable toxic metals, and generating revenue. In this paper, different alkaline leaching techniques were tested in order to dissolve the zinc present in an EAF dust: (i) conventional agitation leaching; (ii) pressure leaching; (iii) conventional leaching following a microwave pretreatment and (iv) leaching with agitation provided by an ultra-sonic probe. Temperature and sodium hydroxide concentration were the variables tested. The highest zinc recovery from the EAF dust, containing about 12% of zinc, was about 74%. This was achieved after 4 h of leaching in a temperature of 90 °C and with a sodium hydroxide concentration of 6 M of the leaching agent. 相似文献