黄钾铁矾渣回收银的试验研究

某黄钾铁矾渣含银221 g/t左右,锌5.94％,铅8.48％,硫10.79％,铁28.81%。银在渣中的形态比较复杂。经还原焙烧,硫化钠活化处理后,用HD1配合HD2进行浮选。试验表明：通过两次粗选三次精选三次扫选流程,试验取得了相当好的指标,最终得到了银品位达到 7515.62 g/t、回收率81.49％左右的银精矿。     

Clean hydrometallurgical route to recover zinc, silver, lead, copper, cadmium and iron from hazardous jarosite residues produced during zinc hydrometallurgy

A hydrometallurgical process for treating the hazardous jarosite residue from zinc hydrometallurgy was proposed, for not only detoxifying the residue, but also recovering the contained valuable metal components. The jarosite was initially activated and decomposed by sintering at 650 °C for 1 h. The sintered residue was leached in 6 mol L⁻¹ aqueous NH₄Cl solution at 105 °C, followed by filtration. The leaching extraction of Zn, Pb, Cu, Cd and Ag are more than 95%. During reduction with Zn powder, more than 93% of Pb, Cu, Ag and Cd can be simultaneously recovered. Then the NH₄Cl leaching residue were leached again in 30 wt% aqueous NaOH solution for 1 h at 160 °C, and about 94% of As and 73% of Si were removed from the residue. The final residue was almost completely detoxified, and contains about 55 wt% Fe, which can be used as an iron concentration.     

Decomposition kinetics of industrial jarosite in alkaline media for the recovery of precious metals by cyanidation

In the present study, the aqueous-slurry decomposition kinetics of industrial jarosite in alkaline media for the recovery of silver by cyanidation was investigated. For this purpose, aqueous-slurry decomposition experiments, using both NaOH and Ca(OH)₂ as alkalinising agents, were carried out in order to (1) study the effect of pH (i.e. 8, 9, 10 and11), contact time and temperature (i.e. 30, 40, 60 and 70°C) on jarosite decomposition; (2) elucidate the rate-determining step of the process kinetics when using NaOH or Ca(OH)₂, by applying the shrinking core model and Arrhenius equation and (3) study the effect of the aqueous-slurry decomposition on the recovery of silver by cyanidation. Results showed that when NaOH was used, the decomposition process was controlled by the chemical reaction with an activation energy of 40.42?kJ?mol^?1, whereas when Ca(OH)₂ was used, the decomposition was controlled by diffusion through a porous layer of CaCO₃ with an activation energy of 21.72?kJ?mol^?1. The alkaline decomposition emerges as a necessary step in order to recover up to 74% of the silver contained in the jarosite by cyanidation.     

有色冶炼中铁矾渣的资源化利用

分析了铁矾渣物相组成,对铁矾渣综合利用方法进行了阐述,分析了高温焙烧分解、酸法浸出、碱法浸出工艺的特点、铁矾渣处理新思路以及工业化应用情况。建议根据各种废弃渣的特性,有效利用其资源,与铁矾渣进行协同处理,有利于实现无害化、资源化、减量化处置铁矾渣等其他废弃渣。     

杂质在铁矾法炼锌过程中的分布规律

用工业生产中的统计数据阐明锌焙烧料中的主要杂质Cu,Cd,As,Sb在黄钾铁矾法炼锌过程中的分布规律。生产数据表明,90%以上的Cu和Cd进入净化渣,75%左右的As和Sb进入矾渣,所得电锌一级品率大于95%。     

用黄钾铁矾法从某铀矿浓酸浸出液中除铁的研究

本文论述了黄钾铁矾除铁法的基本原理以及用于处理某铀矿石的浓酸熟化－淋滤浸出液中除铁的研究结果。结果表明：该法可有效地应用于铀水冶工艺过程。     

A simplified method for estimation of jarosite and acid-forming sulfates in acid mine wastes

In acid base accounting (ABA) estimates of acid mine wastes, the acid potential (AP) estimate can be improved by using the net carbonate value (NCV) reactive sulfide S method rather than total S assay methods but this does not give recovery of potentially acid producing ferrous and ferric sulfates present in many wastes. For more accurate estimation of AP, an effective, site-specific method to quantify acid sulfate salts, such as jarosite and melanterite, in waste rocks has been developed and tested on synthetic and real wastes. The SPOCAS (acid sulfate soils) methods have been modified to an effective, rapid method to speciate sulfate forms in different synthetic waste samples. A three-step sequential extraction procedure has been established. These steps are: (1) argon-purged water extraction (3 min) to extract soluble Fe(II) salts (particularly melanterite), epsomite and gypsum (<10 wt.%), (2) roasting at 550 degrees C (1 h) to remove sulfur from pyrite and other reactive sulfides, (3) HCl extraction (4 M, 30 min) for determination of jarosites. Products (solid and aqueous) have been characterized at each step including the jarosite decomposition process in Step 2 where temperature control is critical to avoid S loss. The sequential extraction procedure was used to quantitatively determine melanterite, epsomite, gypsum, pyrite and jarosite concentrations in a synthetic waste sample containing these mineral phases at 5 wt.% in quartz, and also tested using a tailings waste sample to quantitatively determine epsomite, gypsum and jarosite contents. The method is applicable to most waste samples including those with non-pyrite sulfides but for samples containing significant amounts of sulfur (>1 wt.% S) as copper sulfides, the second step of roasting needs to be excluded from the procedure with an increased time of 4 M HCl extraction to 16 h for jarosite determination.     

从高铟锌精矿中综合回收锌和铟

某锌精矿中铟含量很高,采用黄钾铁矾法处理该高铟锌精矿,在得到较高锌回收率的同时,大部分的铟进入矾渣,少部分进入高浸渣,从矾渣和高浸渣中可回收得到电铟。锌的浸出率高达98.45%;而95.08%的铟进入铁矾渣可有效回收。生产实践表明采用该工艺,铟的总回收率可达72%,锌的总回收率可达92%。可见,黄钾铁矾法工艺处理高铟锌精矿可以达到综合回收锌和铟的目的。     

黄钾铁矾法处理含铟高铁锌精矿

黄钾铁矾法处理高铁高铟锌精矿时,锌的总回收率较高;锌冶炼过程中原料中大部分的铟进入矾渣,少部分进入高浸渣,矾渣和高浸渣经高温焙烧、浸出、萃取、电解和铸锭后即可得到电铟。较好的浸出条件为:中浸始酸40 g/L、低浸始酸30 g/L、高浸终酸60 g/L。已有的生产实践表明采用该工艺铟总回收率可达72%左右,锌的总回收率可达92%。     

Imaging spectroscopy of jarosite cement in the Jurassic Navajo Sandstone

Imaging spectroscopy is a powerful tool for mapping surface mineralogy. Interactions of energy and surface materials on atomic and molecular levels result in specific absorption features that are diagnostic of mineralogy. Hyperspectral airborne sensors such as HyMap have sufficient spectral resolution to identify subtle features over narrow wavelength ranges. An anomalous zone of jarosite cement within the Jurassic Navajo Sandstone in southern Utah was identified with airborne hyperspectral data. To date no other locations of sulfate-rich cements such as this have been documented in the Navajo Sandstone. Here, we use multiple spectral analysis techniques over a micro to macro spatial continuum in order to focus our evaluation on the distribution and relative abundance of jarosite in this area. In this study, imaging spectroscopy is used to help determine the extent of the distribution of jarosite [KFe₃(SO₄)₂(OH)₆], at “Mollie's Nipple” (MN), a significant geomorphic landmark located within the Grand Staircase-Escalante National Monument, in the Jurassic Navajo Sandstone of south central Utah. The extent of the jarosite across the butte is identified in this study by mapping two diagnostic absorption features, referred to as the ∼ 2.26 μm and near-infrared ferric iron absorption features (∼ 0.70-1.15 μm), independently. This analysis shows that there is a single circular zone of abundant jarosite ∼ 1 km in diameter that includes both in-situ and weathered out accumulations. Jarosite formation requires acidic and sulfate-rich fluids, which are unusual for the Navajo Sandstone. Imaging and field spectroscopy provides the spectral resolution needed to map and analyze the mineralogic characteristics of this area; characteristics that may help constrain the conditions under which this atypical butte formed.