Separate grinding of siliceous materials in cement raw materials: improving burnability and reducing energy consumption
摘要
The global cement production is approximately 4 billion tons, serving as a fundamental material in socio-economic development. Clinker, a crucial component of cement, is significantly influenced in performance by siliceous materials. Traditional blended grinding results in the enrichment of siliceous materials in coarse particles, thereby affecting burnability. Based on the investigation of the existing raw meal particle size distribution characteristics, a separate grinding technology for siliceous materials is proposed to optimize the raw meal particle size, enhance burnability, and reduce clinker calcination energy consumption. Through laboratory research and industrial trial applications, the effects of separate grinding on burnability and energy consumption are analyzed, and a correlation model of particle size–composition–energy consumption is established. The results show that when the fineness of siliceous materials is controlled to an R80µm of 5–10%, the f-CaO content in clinker is reduced by over 10%, the calcination heat consumption is decreased by 2.4 kg/t.cl, the energy consumption for the raw meal process is lowered by 0.5 kWh/t, and the kiln output is increased by 1.6%. For the first time, the industrial feasibility of separate grinding of siliceous materials has been systematically verified. A classifier static blade structure based on coarse particle control has been proposed, and a multi-factor coupling model of “particle size-burnability-energy consumption” has been constructed.