Basic Research On The Properties Of High-carbon Ferrochromium Slag And Its Resource Utilization

As the main waste of ferrochrome production,high carbon ferrochromium slag has the characteristics of large emission,complex slag type,heterogeneous composition and great harm to the environment.How to develop and utilize it as a resource is a major problem faced by environmental workers and material researchers.In this paper,based on the systematic analysis and research of high carbon ferrochromium slag,according to its own characteristics,the preliminary research on its development and utilization is carried out,which provides a new idea for the resource utilization of high carbon ferrochromium slag and other industrial solid wastes,as well as reducing the raw material cost of related materials.Based on the study of the basic properties and toxic leaching of high carbon ferrochromium slag,the application of high carbon ferrochromium slag in porous ceramics and multiphase materials was studied.The following meaningful results were obtained:(1)High carbon ferrochromium slag contains a large number of well-grown forsterite and spinel crystals,which are hard in texture,rough and porous in surface.TGDSC analysis found that ferrochrome and iron oxide will decompose at high temperature.The toxicity leaching experiment showed that the leaching concentration of total chromium ion in high carbon ferrochrome slag was 0.25mg/l,which belonged to general solid waste.(2)The porous ceramics prepared with high carbon ferrochromium slag have good comprehensive properties when the rice husk content is 5 wt%,the molding pressure is 5MPa,the sintering temperature is 1175? and the holding time is 90 min.Its apparent porosity is 39.1%,cold crushing strength is 37.9 MPa,acid resistance is 98.65%,and alkali resistance is 99.00%.The results of high concentration methylene blue adsorption experiment showed that the porous ceramics had a strong removal effect for methylene blue.(3)The study on the preparation of forsterite spinel composite material from high carbon ferrochrome slag shows that the composite material has good comprehensive properties when the heat treatment temperature is 1200? and the content of high carbon ferrochrome slag is 70 wt%.The compressive strength at room temperature is 108.8 MPa,the thermal shock resistance is 8 times,and the total chromium ion leaching concentration is 0.14 mg/L.The increase of heat treatment temperature and the introduction of periclase can accelerate the transformation of enstatite into forsterite,thus improving the physical properties and thermal shock resistance of the samples.The existence of spinel can not only resist the thermal stress impact and improve the thermal shock resistance of the sample,but also be conducive to the solid solution of free chromium ions.