Preparation Of High-strength Oil Fracturing Proppant Using Steel Slag

Steel slag is a solid waste produced during steel making,however,its recycling rate is low,which causes environmental pollution and waste of resources.Ca content in steel slag is more,but mostly distributed in silicate and calcium ferrite,and the structure is loose,resulting in poor strength and acid resistance.Brownmillerite,gehlenite,and pyroxene phases are mainly Ca-based mineral phases with high density and strong acid resistance.Therefore,the steel slag is modified to produce these three mineral phases,which is expected to prepare petroleum fracturing proppant products with high strength and strong acid resistance.It can not only effectively utilize the waste resources of steel slag,but also reduce the environmental pollution that caused by metallurgy soild waste.The pure additive modification experiment of steel slag shows that the main phase of steel slag and Al₂O₃sintered in proportion is brownmillerite,but the crushing rate and acid solubility of the sample are high.Gehlenite can be formed after sintering steel slag with Al₂O₃and Si O₂,and the crushing rate and acid solubility after sintering at 1350°C are 6.2%and 3.54%respectively.On this basis,after adding Mg O,pyroxene was generated,while the compressive and acid resistance has been further improved.In order to reduce costs,fly ash and kaolin are used instead of pure additives.The experimental results show that the addition of fly ash can promote the formation of pyroxene and liquid phase,but the performance is poor.The lowest crushing rate is 9.7%and the acid solubility is 4.26%.At the same time,gehlenite-pyroxene can be produced by adding two kinds of ingredients.The lowest breaking rate of the sample is 9.2%,and the acid solubility is less than 5%.Finally,through orthogonal test,the change model of fragmentation rate and the expression of prediction function are obtained,which can provide reference for the research on preparation of high-strength oil fracturing proppant by modification of steel slag ingredients.Figure 76;Table 24;Reference 77...