国外某高硫低锌尾矿锌强化回收试验研究

国外某高硫低锌尾矿中含锌2.69%、含硫47.08%,脉石矿物主要为滑石并且含有大量黄铁矿，硫含量过高是导致该矿石浮选指标差的主要原因。实验室通过条件试验指出石灰用量不足、硫酸铜用量过大导致现场精矿Zn品位低，并通过调整药剂用量、使用组合捕收剂以及添加黄铁矿辅助抑制剂Kg-1显著提高了精矿Zn品位。在最佳药剂制度下，采用一粗三精一扫，中矿按顺序返回的闭路流程，其中扫选不添加石灰，其他药剂减半，三次精选均添加石灰500 g/t调节矿浆pH值，最终试验获得的闭路锌精矿产品中Zn品位为42.86%、Zn回收率为71.93%,达到选厂要求浮选指标，实现了对该高硫低锌尾矿锌的高效回收利用。通过闭路试验探究有无Kg-1的添加对闭路锌精矿Zn品位的影响，试验结果指出Kg-1的引入能有效阻碍浮选过程中黄铁矿的上浮，显著提高锌精矿Zn品位。相对于未加Kg-1的闭路试验，锌精矿Zn品位提升13.76%,说明Kg-1是一种有效的黄铁矿抑制剂。Kg-1是一种有机小分子抑制剂，其分子头基有硫亲固原子，通过水解产生R-CSS^-,能与被硫酸铜活化的黄铁矿表面的Cu²⁺和F...

Experimental study on enhanced recovery of zinc from a high sulfur and low zinc tailings abroad

A foreign high-sulfur and low-zinc tailings contains 2.69 % zinc and 47.08 % sulfur. The gangue minerals are mainly talc and contain a large amount of pyrite. The high sulfur content is the main reason for the poor flotation index of the ore. Through conditional tests in the laboratory, it is pointed out that insufficient lime dosage and excessive copper sulfate dosage lead to low Zn grade of concentrate in the field. The Zn grade of concentrate is significantly improved by adjusting the dosage of reagent, using combined collector and adding pyrite auxiliary inhibitor Kg-1. Under the optimal reagent system, a closed-circuit process of one roughing, three cleaning and one scavenging was adopted, and the middle ore was returned in sequence. Among them, lime was not added in the scavenging process, and other reagents were halved. Lime 500 g/t was added in the three cleaning processes to adjust the pH of the pulp. The final closed-circuit zinc concentrate product obtained in the test had a Zn grade of 42.86 % and a Zn recovery rate of 71.93 %, which met the flotation index required by the concentrator, and realized the efficient recovery and utilization of zinc from the high-sulfur and low-zinc tailings. The effect of Kg-1 addition on the Zn grade of closed-circuit zinc concentrate was investigated by closed-circuit test. The test results showed that the introduction of Kg-1 could effectively hinder the flotation of pyrite in the flotation process and significantly improve the Zn grade of zinc concentrate. Compared with the closed-circuit test results without Kg-1, the Zn grade of zinc concentrate increased by 13.76 %, indicating that Kg-1 is an effective pyrite inhibitor. The mechanism of Kg-1 inhibiting pyrite is to form insoluble complexes with Cu₂₊ ^{and Fe₂₊} on the surface of pyrite activated by copper sulfate, which hinders the adsorption of collector on the surface of pyrite.