超细粒煤对粗粒煤浮选的影响

Effect of superfine coal on flotation of coarse coal

煤炭加工和浮选过程中,超细粒煤是影响粗煤颗粒回收效率的关键因素。这些超细颗粒由于尺寸小、比表面积大,与浮选试剂的相互作用复杂,对浮选效果产生显著影响。然而,目前关于不同超细颗粒对不同浮选试剂吸附特性的了解尚不深入,限制了浮选技术的进一步优化。为深入探究超细粒煤对粗粒煤浮选过程的影响,选3个具有代表性的煤样进行浮选试验。通过对比添加不同灰分的超细煤粒后粗煤粒(>74 um)的回收率变化,研究发现,煤样中添加低灰分超细煤粒时,粗煤粒回收率明显降低;而添加高灰分超细煤粒时,对粗煤粒回收率影响较小。为揭示这一现象的机理,进一步通过接触角和润湿热的测量,研究了超细煤粉颗粒与浮选药剂之间的相互作用。结果表明,低灰分超细煤颗粒对捕收剂和起泡剂均具有强烈的吸附能力,这可能是由于其表面性质更易与浮选试剂发生作用。相比之下,高灰分超细煤颗粒对捕收剂的吸附能力较强,但对起泡剂的吸附能力较弱。表明起泡剂在粗粒煤颗粒的回收中可能具有更重要的作用。本研究不仅揭示了超细粒煤对粗粒煤浮选过程的影响机制,还为浮选技术的优化提供了重要的理论依据和试验指导。

In the coal processing and flotation process,the presence of ultrafine coal particles has always been a critical factor affecting the recovery efficiency of coarse coal particles.Due to their small size and large specific surface area,these ultrafine particles exhibit complex interactions with flotation reagents,significantly impacting the flotation effect.However,the current understanding of the adsorption characteristics of different ultrafine particles towards various flotation reagents is limited,which hinders further optimization of flotation technology.To thoroughly investigate the influence of ultrafine coal particles on the flotation process of coarse coal particles,this study selected three representative coal samples and conducted systematic flotation experiments.By comparing the changes in recovery rates of coarse coal particles(>74 um)after adding ultrafine coal particles with different ash contents,it is found that the recovery rate of coarse coal particles decreases significantly when low-ash ultrafine coal particles are added,while the impact is minimal when high-ash ultrafine coal particles are added.To elucidate the mechanism behind this phenomenon,the interaction between ultrafine coal particles and flotation reagents through measurements of contact angle and wetting heat were further studied.The experimental results indicate that lowash ultrafine coal particles exhibit strong adsorption capacity for both collectors and frothers,likely due to their surface properties that facilitate interactions with flotation reagents.In contrast,high-ash ultrafine coal particles have a stronger adsorption capacity for collectors but a weaker adsorption capacity for frothers,suggesting that frothers may play a more crucial role in the recovery of coarse coal particles.This study not only reveals the mechanism of the influence of ultrafine coal particles on the flotation process of coarse coal particles,but also provides important theoretical and experimental guidance for the optimization of flotation technology.