Batch process overlapping production

Production schedules for batch processes can be sequential, overlapping, parallel, use intermediate storage, or use a combination of these. Such schedules can be analyzed using Gantt charts. Batch processes often produce multiple products in the same equipment and can be distinguished as flowshop or multiproduct plants. Equipment cleaning and material transfer policy have a significant effect on the production schedule. 

More efficient density separation is possible by introducing plastic granules into a pressurised vessel containing a supercritical fluid. By altering pressure and composition the density of such fluids can be controlled to within +0,001 g/cm. This allows separation of all polymers with the exception of those with overlapping densities [6]. Productivity remains a problem, however, since this is a batch process. 

Semicontinuous production processes can be described in a similar way as batch production processes by adding a duration information to a material flow. This makes it possible to handle the overlapping of independent process orders over multiple stages in campaign planning and semicontinuous production planning. 

When production volume is sufficient, it is economical to build one plant for one product. Batch production in a single unit may be limited by maximum reactor size. Holdups of greater than 20,000 gal are handled in separate parallel reactors. To use common upstream and downstream facilities, the reactors may not be operated simultaneously but on overlapping schedules. When long reaction times cannot be avoided, the reaction sections operate batch wise however, feeding reactants and recovering products may be continuous for economic reasons. This practice is typical of many processes, such as the saponification of natural fats in intermediate quantities. In the production of ethanol by fermentation, two reactions (saccharification and fermentation) are operated on a batch basis, while hydrolysis (conversion of starch to dextrin) and product recovery by distillation are continuous. 

There is a clear overlap between the functions of MRP 11/ERP systems and MES systems. Indeed, many MRP 11/ERP functions are moving toward the plant floor, bridging the gap between business and production systems. Some modern process control systems are starting to offer interfaces "upwards" to MRP 11/ERP (e.g., enhanced batch management functionality). Meanwhile, major MRP 11/ERP system suppliers are including MES features in their product range, typically as separate modules that are closely integrated with the... 

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