Study On Occurrence Behavior Of Components And Sulfur Encapsulation Law In Zinc Smelting High Sulfur Residue

The sphalerite oxygen pressure leaching process produces a large amount of high-sulfur slag containing elemental sulfur,which has a good recycling value.However,the zinc smelting high-sulfur slag ore phase is complicated to wrap and embed,which makes the subsequent sulfur direct recovery rate low.In this paper,in order to clarify the component occurrence characteristics in the zinc smelting high sulfur slag,and to investigate the encapsulation law of sulfur and different mineral phases in the high sulfur slag,the process mineralogy was used to initially clarify the component occurrence characteristics in the high sulfur slag,then the method of combining transparent autoclave and high speed camera were used to explored the wrapping law of sulfur and different mineral phases,it will provide a theoretical guidance and basis for improving the sulfur recovery rate in zinc smelting high sulfur slag.Firstly,the process mineralogy analysis of the zinc smelting high sulfur slag was carried out,the phase composition,element content,and intercalation relationship of the leaching residue were clarified.The sulfur content in zinc smelting high-sulfur slag is 59.36%,of which 43.18% exists in the form of elemental sulfur,accounting for72.75% of the total sulfur.Other sulfur-containing minerals can be divided into metal sulfides and sulfates.Among them,metal sulfides are mainly sphalerite,followed by pyrite;sulfate minerals are mainly calcium sulfate.Other gangue minerals are mainly quartz,mica and elemental carbon.According to the results of process mineralogical analysis,five minerals with high content in leaching slag-pyrite,sphalerite,mica,quartz,and gypsum-were selected as the objects of study,and the substrates were made from each of these five materials.The effects of technological conditions such as temperature,additive content,sulfuric acid concentration,and oxygen partial pressure on the contact angle between different substrates and sulfur were investigated by the combination of transparent autoclave and high-speed camera.The experimental results showed that as the temperature increases,the contact angle between different substrates and sulfur gradually decreases,and reaches a stability around 130 ?.As the content of additives increases,the contact angle between different substrates and sulfur gradually increases,and then tends to stabilize,indicating that the inclusion of calcium lignosulfonate can reduce the package between minerals and sulfur.As the oxygen partial pressure increases,the contact angle between different minerals and sulfur gradually increases,indicating that increasing the oxygen partial pressure can also reduce the package between minerals and sulfur.With the increase of acidity,the contact angle between sphalerite,pyrite,gypsum,and quartz decreases rapidly with sulfur,while the contact angle between mica and sulfur increases.This should be related to the nature of the mineral itself..The contact angle between the five minerals and sulfur is in the order of:gypsum>sphalerite>quartz>mica>pyrite.Therefore,pyrite is easier to wrap with sulfur,while gypsum is more difficult.By comparing with the law of occurrence of sulfur in the actual leaching slag and different mineral phases,the law obtained by the simulation experiment is consistent with the law of the actual leaching slag.Finally,the dimensional analysis was used to mathematically fit the experimental data of different substrates and sulfur contact angles under different conditions.Through the establishment of a mathematical model,the degree of influence of different factors on the contact angle was compared,and the standard equation of the contact angle was obtained.