Effect of chlorite on the flotation of pyrrhotite and its implications for elimination by different methods

The effect of chlorite on the flotation of pyrrhotite was systematically investigated through flotation tests, adsorption studies, optical microscopy experiments, inductively coupled plasma emission spectrometer tests, zeta potential measurements, and X-ray photoelectron spectroscopy analysis. Results showed that fine chlorite impaired the flotation of pyrrhotite due to slime coating. To eliminate the adverse effect of chlorite, two different methods were employed. Carboxymethyl cellulose and quartz could remove the slime coating of chlorite and improve the flotation recovery of pyrrhotite, whereas the addition of quartz provided better results. The key to eliminating the adverse effect of chlorite on the flotation of pyrrhotite is to remove the slime coating of chlorite by changing the surface charge of chlorite.     

Effect of cation vacancy and crystal superstructure on thermodynamics of iron monosulfides

Iron monosulfides, Fe_{1 ? x}S (0 < x < 0.125), are extremely complex in their chemical and physical behaviours, which are largely attributed to their nonstoichiometric nature and myriad superstructures. The chemical composition of Fe_{1 ? x}S affects the polymorph formation for iron monosulfides, their mineral reactivity, surface sulfur fugacity, and thermal expansion. In this paper, the effects of cation vacancy and crystal superstructure on the thermodynamics of iron monosulfides are reviewed and discussed.     

某铜铅锌多金属硫化矿电位调控浮选试验研究

某铜铅锌多金属硫化矿铜铅矿物嵌布粒度微细，分离难度大，锌矿物以铁闪锌矿为主，现场仅生产铅精矿和锌精矿且选别指标差。为此，针对矿石性质，采用铜铅混浮-铜铅分离-混浮尾矿抑硫浮锌电位调控浮选工艺，通过控制矿浆电位，混浮粗精矿再磨，选择高效捕收剂、活化剂、抑制剂等措施，使铜铅矿物与锌硫矿物、铜矿物与铅矿物、铁闪锌矿与磁黄铁矿得到了较好的分选。闭路试验获得含铜18．13％、铜回收率55．41％的铜精矿，含铅50．20％、铅回收率83．29％的铅精矿和含锌49．75％、锌回收率86．17％的锌精矿，与现场相比，不仅回收了铜矿物，而且铅、锌精矿质量与回收率都得到了大幅度提高。     

铁闪锌矿的选矿研究概况

介绍了铁闪锌矿在我国的分布特点和铁闪锌矿含铁量与其可选性的关系。从浮选流程结构、铁闪锌矿的粒度、铁闪锌矿的活化、石灰和pH值、铁闪锌矿的捕收剂以及磁黄铁矿的抑制等各主要方面对铁闪锌矿选矿技术的研究和实践进行了较全面的总结归纳和分析，以期对铁闪锌矿选矿的更深入研究和铁闪锌矿及其伴生元素的更高效回收利用有所裨益。     

ZCT中磁磁选机在车河选厂的应用

车河选厂91号富矿石中碰黄铁矿含量高，严重影响选厂后重选段摇床锡的回收，本文介绍采用ZCT中碰机脱除磁黄铁矿，经应用表明，不仅脱除效果好，而且能改善摇床分选效果，提高锡的选别指标．经济效益十分显著．为选厂提高锡的回收指标提供了有效途径。     

Internal deterioration of concrete by the oxidation of pyrrhotitic aggregates

This paper presents research results on the causes of a severe concrete deterioration, which occurred in many building foundations approximately 2 years after construction. Concrete samples were investigated with X-ray diffraction (XRD) analysis, a scanning electron microscope (SEM) and a petrographic examination performed with a stereomicroscope. It was found that the early cracking of concrete stemmed from the oxidation of the pyrrhotite found in the anorthosite aggregates used to produce the concrete. The oxidation process led to the precipitation of iron hydroxides having a higher volume than the original pyrrhotite does. The presence of micas (biotite) close to the pyrrhotite seemed to promote and accelerate the oxidation process.     

生物浸出磁黄铁矿的研究概况

磁黄铁矿矿物组成复杂,且极易氧化;浮选困难,但易于生物浸出。本文从浸出机理、动力学和强化措施等方面阐述了生物浸出磁黄铁矿的研究现状。指出了该技术存在的问题和应用前景。     

硫粗精矿提质降杂试验研究

云南文山都龙多金属矿分选难度大,硫粗精矿中砷和杂质含量高,严重影响企业经济效益。在对硫粗精矿进行工艺矿物学研究的基础上,采用“磁选—深度细磨—浮选”的联合工艺对硫粗精矿进行提质降杂试验研究,并对锌进行回收。所得硫精矿中S、Zn、As品位分别为36.66%、2.72%、0.63%,其中S的回收率为75.73%,锌精矿中Zn品位为40.68%,回收率为52.63%。硫精矿的质量明显提高,提质降杂效果明显,同时还实现了锌的回收。     

Effect of the composition of some sulphide minerals on cyanidation and use of lead nitrate and oxygen to alleviate their impact

An investigation was carried out on synthetic ores containing high purity pyrite, pyrrhotite and chalcopyrite and on two gold ores currently processed to evaluate the impact of cyanicides on cyanidation and to improve the leaching performance by using a pre-leaching, injecting oxygen and adding lead nitrate. With regard to the synthetic ores, it was found that pyrrhotite did not generate a high cyanide consumption while pyrite and chalcopyrite were detrimental. Pre-leaching was deleterious for the ore containing chalcopyrite while pre-leaching with lead nitrate was very efficient to decrease the reactivity of the ore containing pyrite. The two gold ores studied had very different compositions. The low sulphide ore had a low sulphide content (1.36% S), present as pyrrhotite while the second had a very high sulphide content (20.2% S), in the form of pyrite, pyrrhotite and chalcopyrite. The efficiency of the process conditions was peculiar to the ores. The high sulphide ore required a stronger, longer pre-leaching period (12 h) with greater amounts of lime (7.0 kg/t) and lead nitrate (600 g/t) than the low-sulphide ore. The ore with a low sulphide content required a pre-leaching of only 1 h with a small quantity of Pb(NO₃)₂ (50 g/t) and leaching can be performed at 360 ppm NaCN to allow a recovery of 96.4% Au and a low cyanide consumption at 0.18 kg/t. As for the high sulphide ore, cyanidation had to be conducted at 560 ppm NaCN to recover 88.4% Au with a cyanide consumption of 0.80 kg/t. An increase in the amount of lime enhanced oxidation of soluble sulphides. Lead nitrate stabilized copper and iron dissolution by forming a passivation layer at the surface of sulphide minerals. Lead nitrate also prevented the formation of a passive layer at the surface of gold.     

云南某高硫铁矿石深度降硫试验研究

云南某高硫铁矿石因含磁黄铁矿而造成精矿含硫超标。为此，对该矿石进行了旨在降低精矿中硫含量的选矿试验。试验采用弱磁选-浮选工艺流程，通过组合活化剂NC和新型捕收剂DY对磁黄铁矿的有效作用，最终使精矿中的硫降至0.08%，并使精矿铁品位达到65.04%。