Study On Preparation Of Porous Ceramics Using Vanadium-containing Titanium Tailings And Coal Gangue

Domestic mineral and coal resources are concentrated in Panzhihua City,Sichuan Province.Every year,Panzhihua vanadium titanium magnetite and coal mining and utilization process will produce a large number of solid wastes,mainly including vanadium titanium tailings and coal gangue.Because of the large output and low utilization rate,most of the vanadium titanium tailings and coal gangue can only be stacked in a unified way,not only occupying valuable land resources,destroying the production At the same time,there are serious security risks.In this paper,Panzhihua vanadium bearing titanium tailing and coal gangue are used as the main raw materials to prepare porous ceramics by the method of molding and adding pore forming agent.The research contents mainly include mixing technology,porous ceramic blank pressing technology,blank drying technology and porous ceramic sintering technology,and the following research results are obtained.(1)When the horizontal tank mill is used to mix vanadium bearing titanium tailings,coal gangue and pore forming agent,the best process parameters are rotating speed of 70 r/min and mixing time of 15 min.The most influential factors on the compressive strength and falling strength of porous ceramic blank are forming pressure and raw material particle size.The greater the forming pressure,the higher the compressive strength and falling strength of porous ceramic blank.When the drying temperature of porous ceramic blank is more than or equal to 115?,cracks appear on the surface of porous ceramic blank.The best drying temperature is 105?,and the quality is stable after drying for 90min.(2)The main factors affecting the properties of porous ceramics are sintering temperature and pore forming agent content,followed by holding time,raw material particle size,forming pressure,ratio of organic and inorganic pore forming agents.The best technological parameters are:sintering temperature is 1100?,pore forming agent content is 35%,raw material particle size is 140-160 mesh,forming pressure is14 MPa,ratio of starch and calcium carbonate is 10%:20%,holding time is 60 min.The porous ceramics with apparent porosity of 44.1%,water absorption of 34.6%,bulk density of 1.27 g/cm~3 and linear shrinkage of 4.7%can be prepared by this process.(3)The phase and microstructure of porous ceramics show that the main crystalline phases of porous ceramics are pyroxene,calcium feldspar,calcium magnesium yellow feldspar,kyanite,iron oxide magnesium,iron and titanium silicate,etc.different preparation parameters have little effect on the crystal phase composition of porous ceramics,mainly on the content of each crystal phase.The porous ceramics prepared in this paper have three-dimensional connected pores,and the pore distribution is uniform,and the pore size is small,so they are suitable for filtering materials.The research results obtained in this paper provide a new way for the comprehensive utilization of vanadium bearing titanium tailings and coal gangue,which is expected to improve the utilization ratio of vanadium bearing titanium tailings and coal gangue,and provide data support for the preparation of porous ceramics containing vanadium titanium tailings and coal gangue.