| Mineral resources are an unrenewable resource.With the depletion of mineral resources,iron ore tailings are the associated products of iron ore resources development,which has become the largest solid waste in China.How to convert iron tailings into treasure and realize secondary utilization has become a research hotspot of energy conservation and emission reduction.In this paper,the tailings of iron ore tailings that meet the requirements of national standards have been successfully prepared.Through microscopic analysis,the combustion mechanism of ceramic particles of iron tailings was mastered and industrial production was carried out in rotary kiln.At the same time,the properties of ceramic concrete with iron tailings were studied and analyzed.The main contents and results are as follows:?1?Detailed analysis of the chemical composition of iron tailings shows that there are a large number of silica and alumina in iron tailings,basically meet the preparation of basic chemical composition of ceramsite,and seize the mineral composition of iron tailings and differential thermal analysis.Basic features.Bentonite and bauxite are selected as auxiliary materials.The possibility of preparing ceramsite from iron tailings was verified by a large number of experiments,and the preparation process of the iron tailings was studied and analyzed.?2?The plasticity of raw materials was analyzed.It is found that when the moisture content is 25%30%,the ceramic granule of iron tailings has the best spherification performance and has higher early strength.Iron tailings:bentonite:bauxite=7:2:1,10%of the total quality of powder coal powder.Combustion system are optimized by the orthogonal test,the iron tailings ceramsite laboratory determined as follows:preheat temperature of350?.The preheating time is 30 minutes and the calcination temperature is 1160?.And the calcination time is 10 minutes,natural cooling.In the above mixing ratio and combustion system,the preparation of iron tailings ceramic particles has the basic performance test results:the bulk density is 820 kg/m3,the apparent density is 1855 kg/m3,the water absorption rate is5.63%,and the tube pressure strength is 7.91 MPa.Each performance index can meet the requirements of GB/T 17431-2010 lightweight aggregate and the test method of 900 ceramic particles.?3?the analysis of the combustion mechanism of ceramic granule of iron tailings shows that the main mineral composition of the finished ceramsite is quartz,feldspar and mullite,all of which contribute greatly to the strength of ceramsite.At the same time,due to the high content of Fe2O3 in iron tailings,it can not only reduce the combustion temperature of ceramic particles,but also reduce the density of ceramic particles by reducing the composition of gas generation through C.In the microscopic analysis,it can be clearly seen that there are more liquid phases in the ceramics,which have higher strength,and the generated liquid phase is filled between the ceramic particles,making the ceramic particles relatively dense.?4?large-scale industrial test of ceramic particles through industrial rotary kiln.The study found significant differences between industrial and laboratory tests.Because of the different heating methods,the temperature required for industrial experiments is lower than that in the laboratory.100?or so.Basic performance test results for the preparation of ceramic:860 kg/m3 density,apparent density of 1970 kg/m3,bibulous rate is 3.94%,the cylinder compression strength 5.59 MPa,slightly lower than the results for the preparation,but also meet the national standard requirements.?5?the preparation of ceramic particles,using industrial rotary kiln to trial production of iron tailings ceramsite concrete,found that there are four strength grade LC15ceramsite concrete of LC30,can use the strength of 5.59 MPa cylinder arrangement on ceramsite.Through the basic properties test of iron tailings ceramic coagulation,its basic performance meets the actual needs of the project. |
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