Experimental And Mechanism Study On Direct Reduction Of Bayan Obo Concentrate By Rich Iron Slime

As a by-product of coal washing process,coal slurry is characterized by water loss,air drying and rapid impact on the environment.However,there are few studies on its utilization,and its price is low.The way of treating slime is generally on-site or Emissions,due to their high viscosity,high ash content,high moisture content and difficulty in water treatment,make their use more difficult.The fixed carbon in coal slime can be used as a reducing agent to reduce iron ore.In order to solve the problem of comprehensive utilization of coal slime and provide a new way for the comprehensive utilization of coal slime,this paper uses coal slime as reducing agent for direct injection of Baiyun Obo iron concentrate.reduction.The traditional method of smelting Baiyun Ebo iron concentrate is blast furnace iron-making.The main problem of blast furnace iron-making is that its greenhouse gas CO2 emissions are large and have an impact on the environment.To solve the problem of CO2 emission,clean production,metallurgists study the direct reduction process.For example,direct reduction of pre-reduction,gas-based production of sponge iron,and the like.The main research agent of this paper is the slime produced by Shendong Group in Baotou District.The research shows that the coal ash produced in Baotou area contains a certain amount of iron oxide,which is called iron-rich slime.In this paper,the iron-rich coal slurry is used as a reducing agent to carry out the experimental study on the reduction of Baiyun Obo iron concentrate.The effects of temperature,carbon ratio and time on the metallization rate are investigated.Using orthogonal test slime obtained iron-rich iron ore direct reduction factors influence the relationship between primary and secondary,and examine the additive(Na2CO3?CaCO3?Na2B4O7)And the effect of coal slime types on the direct reduction of carbon-containing pellets,expanding the scope of research applications.The experimental results show that the factors affecting the reduction reaction are temperature,carbon ratio and time;the optimum process parameters of iron-rich slime direct reduction iron concentrate are reduction temperature 1200 °C,carbon ratio of 1.3,reduction time of 30.minute.Study and compare the common reducing agent anthracite,investigate the influence of different factors on carbon-containing pellets,and the economic advantage of iron-rich coal slurry as reducing agent.The image analysis and morphology analysis of the reduced products by X-ray diffraction(XRD)and scanning electron microscopy(SEM)showed that the iron-rich slime as the reducing agent has lower indexes than the anthracite,but considering its low price,As a reducing agent,the cost of reduced iron can be reduced,and its economic utilization value is high.The reaction process of the quenching of Baiyun Obo concentrate in different temperature ratios by thermo gravimetric analysis was carried out by thermo gravimetric analysis.The kinetics of carbon-containing pellets in this experiment was studied by thermo gravimetric analysis,and the carbon-containing pellets were calculated according to the TG curve.Reaction score.The results of the study indicate that an excess of carbon can promote the reduction reaction.The reaction system carries out a two-step reaction mechanism in the experimental temperature rising stage.The gasification rate of carbon affects the reaction process,and the temperature is closely related to carbon gasification,which becomes the decisive factor of the reduction reaction.The reaction fraction shows that the effect of temperature on the reduction reaction is remarkable.