Research Of Slag Portland Cement Prepared With Tailings Of Vanadium From Stone Coal

Vanadium tailings of direct leaching from stone coal is the waste residue which was obtained by stone coal after acid vanadium extracted and rich in carbon. At present, vanadium-extraction tailings mostly are stockpiled to handle, not only occupied land resources, but also lead to environmental pollution problems. With the continuous improvement of the non-ferrous industrial policy and environmental protection requirements, Development of circular economy is the only way in Southern Shaanxi vanadium industry for sustainable development. Comprehensive utilization of vanadium tailings is an important research topic.In this paper, tailings of vanadium extraction from southern Shaanxi stone coal was as the research subjects. On the basis of literature and systematic analysis of physical and chemical properties of the tailings, combining the characteristics of cement production, the ratio, process and performance are studied for preparation slag cement clinker by vanadium tailings slag to improve the utilization of vanadium tailings.Prepared slag cement through experiments meet national standards, and get the relevant process parameters:The main chemical composition of tailings from Stone Coal were Si O2?Al2O3?Ca O and SO3, loss on ignition amounted to 8.81%.Has certain radioactive and coarser granularity, need grinding as a raw material for cement clinker.The experiment determined the conditions to make cement clinker, using tailings powder, calcium carbonate, clay and iron powder mixed in different mass ratio, pressure forming, after fully dried and sintering at 1350 ?, 1400 ? and 1450 ?respectively, then cooling and grinding. The main components of its products was Ca3 Si O5,Ca2 Si O4,Ca4Al2Fe2O10 and Ca3Al2O6.The chemical composition and the particle size distribution are in line with the cement clinker. The better condition is fired at 1400? with the amount of 8% clay.A good performance slag Portland cement can be formulated by cement clinker made of the Vanadium tailings from stone coal. Standard consistency water yield, stability, setting time and strength of the slag Portland cement prepared by clinker fired at different temperatures and gypsum content of 3% and 5%were investigated, in the amount of 20% slag. Comparative results show that the stability, setting time are in line with national standards, strength all in compliance with slag cement level 32.5, partly in line with slag cement level 42.5.The slag Portland cement prepared by the cement clinker fired at 1400 ?, clay and gypsum content of 8% and 3%overall performance is the best.It is feasible to use the Vanadium tailings from stone coal to prepare slag Portland cement, provides an effective way for use of vanadium tailings form stone coal,has an important guiding significance and application value for vanadium industry to achieve sustainable development in southern Shaanxi.