Analysis of Production Process and Technical Indicators of New Lime Kiln
The new type of lime shaft kiln has achieved a dual improvement in calcination efficiency and product quality through structural optimization and intelligent control. The core process is divided into four stages: preheating zone, calcination zone, insulation zone, and cooling zone. The preheating zone uses the waste heat from the kiln roof exhaust gas to preheat limestone to 850 ℃, with a pre decomposition rate of 30%; The temperature of the calcination zone is precisely controlled between 1150-1250 ℃. Through the design of a three-layer annular furnace and wavy furnace walls, the materials are rolled and mixed inside the kiln to ensure the uniformity of calcination; The insulation tape prolongs the residence time of high-temperature lime by 8.4 hours, allowing the undecomposed calcium carbonate to fully react and reducing the firing rate to below 5%; The cooling zone adopts forced air blast rapid cooling, and the lime temperature is below 60 ℃ before being discharged from the kiln, with the activity level increased to 360-440ml.
In terms of technical indicators, the new type of vertical kiln has a daily output of 200-250 tons per kiln and a heat consumption of 110-115 kgce/t, which is 25% lower than traditional kiln types; Wide fuel adaptability, can use natural gas, anthracite or industrial waste gas, with a standard coal consumption of 140kg/t lime; The total height of the kiln body is 34.2 meters, the inner diameter of the calcination zone is 3.1 meters, and a four layer composite insulation system is used. The temperature of the kiln skin is only 60 ℃ higher than the environment; The environmental protection system is equipped with cyclone and water film dust removal, with dust emission concentration ≤ 45mg/Nm ³ and NOx emission ≤ 300mg/m ³. Through the use of inverted cone fabric and disc four point ash removal technology, continuous and stable production is achieved, with a calcium oxide content of 90-95% and an over burning rate of<2%, fully meeting the needs of high-end fields such as metallurgy and chemical engineering.
