Annual aqueous processing costs

Fig. 24-12. Annual aqueous processing costs vs. plant throughput for 825-Mw-tvvo-fluid LMFR.

Figure 6, Normalized annual costs for a S-year accounting life of the equipment. Comparison between an aqueous cleaning process and a supercritical (X>2 cleaning process.

In this chapter, a suitable entrainer for this acetic acid dehydration system will be selected from several candidate acetates. Steady-state tray-by-tray column simulation will be used to determine the best entrainer with minimum total annual cost (TAC). Optimum process design and operating conditions will be determined to keep a high-purity bottom acetic acid composition and also to keep a small acetic acid loss in top aqueous draw. The overall control strategy of this column system will also be proposed to hold both bottom and top product specifications in spite of feed rate and feed composition disturbances. In the control study, conventional control strategy using only tray tempaature measurements will be considered so that the result of this study can easily be used directly in industry. 

Based on this lactide intermediate method. Nature Works LLC has developed a patented, low cost continuous process for the production of lactic acid-based polymers. The process combines the substantial environmental and economic benefits of synthesizing both lactide and PLA in the melt rather than in solution and, for the first time, provides a commercially viable compostable commodity polymer made from annually renewable resources. The process starts with a continuous condensation reaction of aqueous lactic acid to produce low molecular weight PLA pre-polymer (Fig. 6.5). 

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