Cu is the most important component in Cu slag, which is usually recovered by flotation. However, the crystalline state of Cu slag is not conducive to flotation, which limits the recovery of Cu. This study investigated the effect of Na₂CO₃ on the crystalline state of Cu slag and the recovery of Cu by flotation. The mechanism was investigated by thermodynamic, viscosity, X-ray diffraction (XRD) analyses and scanning electron microscopy (SEM). The results of thermodynamic, viscosity and XRD analysis demonstrate that Na₂CO₃ is beneficial for the transformation of fayalite to low-melting point materials, such as Na₂SiO₃, Na₄SiO₄ and NaFeSi₃O₆, thereby reducing the viscosity of Cu slag. Moreover, SEM results indicate that the addition of Na₂CO₃ during the melting modification process can promote the aggregation of Cu-bearing minerals and simplify its intercalation relationship with gangue minerals. The flotation results verify the above conclusions that at 10% Na₂CO₃, the Cu flotation recovery index is the best. Compared with that without Na₂CO₃, the use of Na₂CO₃ has resulted in increased Cu grade and recovery by 3.544% and 28.94%, respectively.

中文翻译：

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用Na2CO3优化铜渣的结晶态以提高浮选铜的回收率。

铜是铜渣中最重要的成分，通常通过浮选回收。但是，铜渣的结晶状态不利于浮选，限制了铜的回收。本研究研究了Na ₂ CO ₃对铜渣的结晶状态和浮选法回收铜的影响。通过热力学，粘度，X射线衍射（XRD）分析和扫描电子显微镜（SEM）研究了该机理。热力学，粘度和XRD分析结果表明，Na ₂ CO ₃有利于将铁橄榄石转变为低熔点材料，如Na ₂ SiO ₃，Na ₄ SiO ₄和NaFeSi ₃ O ₆，从而降低了铜渣的粘度。此外，SEM结果表明，在熔融改性过程中添加Na ₂ CO ₃可以促进含铜矿物的聚集，并简化其与脉石矿物的插层关系。浮选结果验证了以上结论，即在10％Na ₂ CO _3下，铜的浮选回收率最好。与不使用Na ₂ CO _3的情况相比，使用Na ₂ CO ₃可以使铜的品位提高，回收率分别提高3.544％和28.94％。