In tropical countries, such as Thailand, the variation of tree moisture content can be significant based on seasonal variations in rainfall. Pulp mill operation optimization accounting for wood moisture variation was used to determine optimal operation conditions and minimize production cost. The optimization models were built using empirical modeling techniques with simulated data from the IDEAS software package. Three case studies were performed. First, a base case of nominal annual operation at a fixed production rate was used to calculate production cost that varies with wood moisture content. The second case is annual optimization where production was allowed to vary monthly over an annual cycle to minimize production cost. For the third case, real-time optimization (RTO) was used to determine optimal production rate with the wood moisture content varying every 3 days. The rolling horizon approach was used to schedule production to keep inventory levels within bounds and with a penalty applied to deviations from the annual expected values of inventory. The advantage of RTO in accounting for moisture content variation was confirmed by annual production costs results simulated for 20 years. These results statistically demonstrated that the overall cost was reduced compared to the second case of monthly production targets.

中文翻译：

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木材水分含量变化对纸浆厂运营的实时优化

在热带国家，例如泰国，基于降雨的季节性变化，树木水分含量的变化可能很大。通过考虑木材水分变化的纸浆厂操作优化来确定最佳操作条件并最大程度地降低生产成本。使用经验建模技术和来自IDEAS软件包的模拟数据来构建优化模型。进行了三个案例研究。首先，以固定生产率的名义年度运营量为基础，计算随木材含水量变化的生产成本。第二种情况是年度优化，其中允许在一个年度周期内每月更改产量以最小化生产成本。对于第三种情况，实时优化（RTO）用于确定最佳生产率，木材含水量每3天变化一次。滚动式水平方法用于计划生产，以将库存水平保持在范围之内，并对偏离年度年度库存值的情况施加罚款。通过模拟20年的年度生产成本结果，可以确定RTO在解决水分含量变化方面的优势。这些结果从统计学上证明，与第二个每月生产目标的情况相比，总成本有所降低。通过模拟20年的年度生产成本结果，可以确定RTO在解决水分含量变化方面的优势。这些结果从统计学上证明，与第二个每月生产目标的情况相比，总成本有所降低。通过模拟20年的年度生产成本结果，可以确定RTO在解决水分含量变化方面的优势。这些结果从统计学上证明，与第二个每月生产目标的情况相比，总成本有所降低。