Research On The Key Technology And Equipments Of Calcining Process Of Black Talc

Scientific, comprehensive development and efficient utilization of non-metallicmineral resources to meet the needs of social development and progress of scienceand technology is the inevitable development trend of non-metallic mineralprocessing industry. As an important nonmetallic mineral beau montage, talc hasmany performances such as good insulation, heat resistance, adsorption, lubrication,and its market demand is very big. Although domestic talc reserves is big, but mostof the talc is black talc with low and medium grade. How to increase the intensity ofdevelopment and processing of black talc resources, improve the quality of talc, andrealize the reasonable utilization of resources, is a research subject, which hassignificant economic benefit.The main purpose of black talc processing is to improve the whiteness. Studiesconfirm that black talc after a certain calcination of temperature and time conditionscan be converted into the high quality talc, which white degree meets therequirement. So the calcining process is the main development way. Domestic blacktalc industry started relatively late, due to the reason of backward processingtechnology and equipment, talc industry still gives poor quality of processedproducts, and priority to with undressed ore or raw product export. This way causesthe waste of resources. This topic confirms the production process of calciningprocessing of the black talc to meet the industrial, continuous, large-scale processing,and its key technology and equipment is pelletization and dynamic calcination.First, the current calcining process of the black talc has two kinds, analyse thecalcining methods of the static calcination and the dynamic calcination. Based on theadvantages and disadvantages of calcining methods, this topic designs a new typetechnology of calcined black talc. The powder of black talc is prilled into ballsbefore entering the calcined rotary kiln. The application of pelletization and dynamiccalcination technology can improve the liquidity and heat transfer effect of the blacktalc, and guarantee maximally the quality of calcined product and performancecharacteristics. And the topic researches the key equipments of the calcination of theproduction process of calcined black talc. Secondly, according to the purpose of pelletization of the black talc powder andthe quality and performance requirements of the ball, through comparing variouspelletized technology, this topic chooses the pre-water adding pelletized technology,and analyse the technological process of the pre-water pelletization, and research thekey equipment of the pre-water pelletized machine. According to the productioncapacity of the designed process and the index of pelletization, calculated therelevant technical parameters of pelletizing equipment, and complete the overallstructure of pelletizing equipment.Finally, the topic researches the equipment of the black talc calcined rotary kiln.Aiming at the shortcomings of the conventional rotary kiln structure, cancelling theconventional girth gear and pinion drive, according to the friction drive theory,rollers employ the direct friction drive. According to the condition of the directfriction drive of kiln, using the new type of two-support rotary kiln, which hassplined tyres and self-aligning rollers and longitudinal roller guide, then completingthe overall structural design of the direct friction drive and two-support rotary kilnroller. The drive system adopts hydraulic drive scheme, including the calculation ofhydraulic parameters and selection of hydraulic components. The direct frictiondrive and two-support rotary kiln roller carries out the finite element analysis,according to the stress and deformation cases of barrel and tyres and rollers, as toprovide theoretical basis for the structural design of rotary kiln.