Study On The Effect Of High Sulfur Substances On The Clinker Calcination Process And Desulfurization Strategy

Because of its alkalinity and high temperature particularity,cement kiln has always been an excellent place to treat solid waste.However,due to its particularity,there are still large problems in the treatment of high-sulfur substances in cement kilns.Due to the high sulfur content in the high-sulfur materials,the normal operation of the cement kiln and the quality of clinker will be seriously affected by the excessive treatment capacity.Therefore,the cement industry is not willing to deal with the high-sulfur solid waste too much,nor is it willing to use high-sulfur coal on a large scale.In this paper,the physical and chemical properties of water-based rock cuttings and high-sulfur coal are studied,and the proportioning calculation is carried out according to their composition.The water-based rock cuttings are proportioned by the internal mixing method,with the mixing amount of 1-5%.Four kinds of high-sulfur coal and standard coal are respectively included in the proportioning calculation and compared with each other.Relying on the support of the project,on-site tests were conducted on water-based rock cuttings and mineralizers.Cement companies with daily production lines of 2500 tons and 5000 tons were selected for on-site tests,and the clinker and cement produced on site were sent to relevant testing institutions for quality inspection.The main conclusions are as follows:(1)With the increase of the amount of water-based rock cuttings,the burnability of the clinker becomes significantly worse,the diffraction peak of tricalcium silicate in the XRD diffraction peak also gradually weakens,and the diffraction peak of free calcium oxide gradually strengthens.The petrographic pictures also show that with the increase of the amount of water-based rock cuttings,the development of tricalcium silicate crystals is affected.(2)After adding four kinds of high-sulfur coal into cement raw meal,the experimental results show that the increase of sulfur content has a promoting effect on the burnability of cement clinker at low temperature stage,but has no direct impact on the burnability at high temperature stage.The petrographic diagram of high sulfur coal samples has a large gap.The mineral phases of the clinker of the four high sulfur coals are poorly developed,and the mineral dissolution phenomenon is relatively serious.(3)The addition of mineralizer can improve the burnability of clinker and reduce the free calcium oxide in clinker sharply.The addition of mineralizer promoted the development of tricalcium silicate crystals in cement clinker.The experimental results show that the addition of mineralizer is conducive to the calcination of clinker and reduces the influence of sulfur on the calcination process of clinker.(4)After increasing the three-rate value of four kinds of high-sulfur coal clinker,the four kinds of coal samples showed different experimental results.In comprehensive consideration of the performance of cement clinker,the proportioning method with a ratio of2 can make 2# and 3# high-sulfur coal produce normal cement clinker,and the method of increasing the three-ratio can alleviate the negative impact of high-sulfur coal on the clinker calcination process to a certain extent.(5)The field test shows that the chemical and physical indexes of the cement clinker and cement calcined at 2% and 5% content meet the corresponding national standards.In terms of environmental protection,heavy metal indicators and environmental impact assessment indicators meet national standards.Field tests show that the strength of clinker is guaranteed and the utilization rate of water-based rock cuttings is improved by adding mineralizer.