【作者】 罗俊国；

【导师】 刘钟海； 郭用坚；

【作者基本信息】 四川大学 ， 化学工程， 2003， 硕士

【摘要】 本文通过对现有复肥生产工艺现状和发展趋势的分析，结合四川天化股份有限公司的生产条件，选定并开发了适合川天化的改进复肥生产工艺——尿液喷浆转鼓造粒多元复合肥生产工艺，该工艺具有投资省、自动化程度高、产品规格易于调整的优点。 论文通过对生产工艺过程的理论探讨和生产实际运行，得出了系统稳定运行的适宜工艺条件为：造粒机出口温度60℃左右，冷却机出口温度70℃左右，干燥机进口温度120℃左右，出口温度50℃左右，热风量为28,000m~3／h。雾化喷嘴采用四川大学压力式专利喷嘴，尿液压力1.6Mpa。0.4Mpa压力蒸汽的用量控制在使造粒后物料的含水量低于4％。在DCS系统的自动控制下，该工艺生产出的产品质量较稳定，合格率高，球形度大于0.8，产品水分小于1.8％，单颗粒抗破碎强度大于17N，产品养分有效含量误差小于1％。针对生产运行中出现的问题，通过对双层振动筛分装置的改进，将不锈钢筛网正方形孔改成长方形孔，有效避免了物料的堵筛现象，并在振动筛上方加一个特殊的防护罩，大大降低了跑料现象，极大地改善了车间操作环境。该工艺采用沉降室和冲击型湿式洗涤塔，能有效除去尾气中的粉尘，保证尾气粉尘含量低于30mg／m~3而达标排放。该项目的经济分析结果表明，其投资回收期较短，仅3～4年，年税后利润约400万元，具有较大的经济效益。更多还原

【Abstract】 Based on the analysis of the present compound fertilizer production processes and the developing trend, a new process suitable for the Sichuan Tian Hua Limited company is selected and developed. By a spraying rotary granulation process using melted urea, this process effectively reduces the investment and makes the production process highly automation . Moreover, the component of the fertilizer product in this process is also very convenient to adjust.Depending on analysis to the process in theory and operation, the obtained optimal operation conditions are that the outlet temperature of granulator, cooler and dryer is about 60 , 70 and50, respectively, the inlet temperature of dryer is about 120, and the hot air flow rate is 28,00m3/h, the amount of 0.4MPa steam added must maintain the water content of the fertilizer from the granulator less than 4%. Through the pressure sprayer at 1.6Mpa, the product show a higher mechanical strength over 17N for a single granule, a good degree of sphericity over 0.8, and lower water content less than 1.4% by weight under the control of DCS. The openings of the shaking sieve are changed to rectangle from square, and the sieve is covered by a shield which effectively avoids the illusion of materials and improves the environmental condition. The fines in the flue gas are collected by a gravity settler and a wash tower and the result meets the need of environment that the concentration of the exhaust must be less than 30 mg/m3. The economical analysis shows that this process can create good economic benefit with a short investment refunding period and a good annual profit up to 4 million RMB after the taxes.更多还原