近红外分析技术在流化床一步制粒工艺中水分控制的应用

Application of near infrared analysis in moisture control of one-step fluidized bed granulation process

中文关键词:  近红外  流化床  一步制粒  在线检测

英文关键词:Near infrared  Fluidized bed  One-step granulation  online analytical technology

中文摘要:

      目的 研究了近红外(near-infrared, NIR)光谱技术在监控流化床一步制粒过程中颗粒水分应用的可行性。方法 运用非接触式探头对制粒全过程扫描采集光谱。选取光谱采用4种不同的方法建立了4个水分预测模型; 分别使用4个模型对干燥终点的物料水分进行预测, 优选出最佳建模方法。结果 4个模型的决定系数(r2)全部大于95%, 均方根误差(RMSECV)全部小于0.25。水分平均误差小于0.13%, 水分最大误差0.19%, 工艺要求水分误差≤±0.5%。3种方式中, 同时满足“水分+温度”两者区间范围的终点物料水分与目标值的偏差最小。结论 本研究提出了一种新的“温度+水分”控制方法, 中间产品的水分和温度都满足工艺要求时判定为一步制粒工艺的干燥终点。将温度、水分、温度+水分, 3种方式作为干燥终点的判定条件, 该方法满足工艺要求。近红外分析技术能够准确预测流化床一步制粒过程中间产品的水分, 其与温度控制相结合作为干燥终点判定的方式, 优于单一干燥终点判定条件。本文提出了一种多变量控制流化床干燥终点的新思路。

英文摘要:

      Objective To study the feasibility of near infrared spectroscopy (NIR) in monitoring the moisture content of particles in one step fluidized bed granulation. Methods Non-contact probe was used to scan and collect the spectrum in whole process of pelleting. Four moisture prediction models were established by four different methods. Four models were used to predict the moisture content of materials at the drying end point, and the best modeling method was optimized. Results The determination coefficients (r2) of the four models were all greater than 95%, and the root mean square error (RMSECV) was all less than 0.25. The average moisture error was less than 0.13% and the maximum error was 0.19%. The moisture error was less than or equal to 0.5%. Among the three ways, the deviation between the moisture and the target value was the smallest at the end of the material when satisfies the range of “moisture+temperature”. Conclusion A new “temperature+moisture” control method is proposed in the paper. When the moisture and temperature of the intermediate product meet the process requirements, it is determined as the drying end point of the one-step granulation process. Temperature, moisture, temperature+moisture, three ways were used as the judge conditions of the drying end, it meets the process requirements. The near-infrared analysis technology can accurately predict the moisture of the intermediate product in the one-step granulation process of the fluidized bed. The combination of temperature control and near infrared analysis technology is better than the single drying end-point determination condition. T It proposed a new idea of multi variable control of drying end-point of fluidized bed.