Study On Enrichment And Wave Absorption Of Iron Components In Copper Metallurgical Slag

China has the largest tailing stock and low utilization efficiency.For example,the TFe content in the copper tailings is about 10%generated by the beneficiation plant of Baiyin Nonferrous Group Co.Ltd.Moreover,the TFe content in the copper smelting slag is up to 40%,and also contains a small amount of valuable elements such as aluminum,lead,zinc,copper,etc.With the development of science and technology,the safety problems caused by electromagnetic radiation have become increasingly prominent.To prevent electromagnetic radiation,ferrite is one of the more widely studied absorbing materials,among which ferric oxide?Fe ₃O₄?is a kind of anti-spinel magnetic material.In this work,the ferric oxide?Fe₃O₄?absorbing materials prepared by melt-modify the copper smelting slag,which not only recovers the valuable metal element iron,but also provides experimental and theoretical guidance for the high value-added utilization of the slag.Furthermore,it opened up a way to recycle and reuse non-ferrous metal resources.The main conclusions of this work are as follows:?1?The contents of Si O₂ and TFe in the copper tailings are 67.28%and 8.00%,and they mainly exist in the form of quartz and oblique chlorite,respectively.In the copper smelting slag,the TFe content is up to 36.80%,and mainly exists in the form of fayalite and iron orthosilicate.?2?Thermodynamic analysis shows that the structure of the fayalite in the copper smelting slag is stable,and it is difficult to be oxidized at high temperatures.However,because the affinity between Ca O and Si O₂ is far greater than Ca O and Fe O,adding Ca O as a modifier promotes the decomposition of the silicate when the temperature is higher than 1000?,which is beneficial to the precipitation of magnetite phase and magnetic separation in copper smelting slag.?3?The prepared absorbing material can absorb electromagnetic waves with different wavelengths by controlling roasting temperature.The maximum RL is-40.6d B under the optimal condition of 1300?,2.0 mm and 9.52 GHz.Grain size of magnetite and the loss of electromagnetic waves increase with increasing time.The prepared absorbing material can absorb electromagnetic waves with varying degrees by controlling roasting time.The maximum RL is-30.8 d B under the optimal condition of 2 h,2.5 mm and 11.76 GHz.The precipitation of magnetite increases with time,increasing the loss of electromagnetic waves.?4?Samples with a basicity of 0.4 have strong electromagnetic reserve and consumption capacity in the prepared absor bing materials with copper slag.The maximum RL is-26.9 d B under the optimal condition of 5.0 mm and 9.52 GHz.The magnetic loss of the material due to natural resonance.Dielectric relaxation process exists in the high frequency result in dielectric loss.When the sample is mixed with the iron powder,the storage loss capacity of electrical energy reduced,and the storage loss capacity of magnetic energy increased.The frequency corresponding to the minimum reflection loss of the sample shifts to a low fr equency.At the same thickness,the frequency bandwidth increased and the attenuation constant of the sample also increased.