Theoretical Analysis And Experimental Research Of RHF Treatment On Matallurgical Zinc-bearing Wastes

Rotary hearth furnace of coal-based direct reduction method is more successfulhandling of the process of the steel plant of solid wastes, and its advantages on themetallurgy of zinc-bearing dust has a good adaptability, zinc removal efficiency.Through the analysis of physical and chemical properties of the steel plantmetallurgical zinc-bearing dust and sludge, proposed to use self contain carbon ofmetallurgical dust based on production of carbon-containing pellets, use rotaryhearth furnace high temperature heating process to separate zinc of the metallurgicalzinc-bearing dust. Have a theoretical analysis on the rotary hearth furnace processingdeal with zinc-bearing dust, and investigate the reduction characteristics,thermodynamic conditions, reduction carbon consumption and self-heating reductioncharacteristics of iron oxide and zinc oxide under the carbon-containing pelletconditions, to improving the theoretical basis of experimental study. To build asimulation of the rotary hearth furnace heating process experimental platform on thebasis of theoretical analysis, the rotary hearth furnace process’s briquetting, drying,reduction roasting for the object, launched experimental studies, the appropriateprocess parameters. Assumptions to simplify the pellet material layer transferprocess and its simulation.Zinc-bearing dust briquetting experiment is used experimental laboratory rollerball press machine to briquetting ball for the research object. Investigate Influencethe binder type, binder amount, moisture content, carbon content on falling strengthand compressive strength of green ball and bake ball; On the basis of theexperimental results of a single binder, through the orthogonalregressionexperimental data to study amount, combination of binder to influence onfalling strength and compressive strength of green ball and bake ball. Alsoinvestigated the influence of drying temperature and drying time of processparameters on the moisture content, falling strength and compressive strength ofgreen ball and bake ball.Reduction the roasting pellets experimental use the high temperature furnacesimulation the rotary hearth furnace to reducing roasting, use zinc-bearing dust asraw material carried out orthogonal experimental study of the five factors and four levels, through an intuitive method and variance method to research influence ofMaterial layers, the carbon content, temperature, time, and the atmosphere on theperformance of the metal pellets, carried out influence of of various factors ondezincification rate, metallization and compressive strength the roasting pellets,proposed optimization of process parameters the rotary hearth furnace roasting.In order to study the heat transfer process of the rotary hearth furnace pelletmaterial layer, through reasonable simplification of the pellet material layer transferprocess, the heat transfer processof the ball the regiment material layer as a flue gasheat transfer on the pellet material layer, thermal conductivity of the pellets withinthe material layer, thermal conductivity between the the pellet and bottom refractoryof combined a variety of heat transfer. Established a heat transfer model, andnumerical calculations on the location of the temperature of the material layer, toobtain the temperature and time relationship of distribution of the pellet layer, and byexperimental measurements of the surface of the material layer and the bottom of theheating curve of the simulation results were validated. Research the influence of thematerial thickness of the pellets, bottom temperature, flue gas heat transfercoefficient and thermal conductivity of the pellet on the pellet material layer transferprocess.