Batch ordering

Run different methods within a batch of multiple samples Last minute change to the batch order... 

Figure 5.2. First-order plot for reversible reaction in batch order.

Thus the echelon faces a demand with a mean of 100 units and a standard deviation of 141.42 units. Notice that the increased standard deviation of demand at the echelon reflects both order uncertainty as well as the lumpiness caused by the batched ordering from locations. 

The traditional techniques used by Valvex for making production schedules are based on meeting forecasts or reaching preset inventory levels. Frequently, large batch orders are processed at each department based on the workflow, and materials are pushed to the next department after the jobs are finished. This type of flow usually causes excess inventories, long cycle times, and some non-value-addedactivities.Evenafterimplement-ing the e-SCM system, these issues were not fully resolved. However, these issues can be tackled by... 

The batching order and procedure must be followed exactly in order to produce the results desired in both the slip and the final tape. 

The effect of moving the curve to the left on the economic batch/order quantity is seen in Figure 5.13. 

Figure 5.13 Reducing the economic batch/order quantity...

Customer sales orders for products are tracked against corresponding purchase orders made to suppliers as well as existing inventory holdings, while optimal inventory holding calculations are made through a combination of sales forecast, lead time, and economic replacement quantities (ERQ). In Bossard s case, ERQ is based on similar calculation to economic order quantity, but with an adjustment for real-world constraints in batch order quantities. 

In general terms, if the reaction to the desired product has a higher order than the byproduct reaction, use a batch or plug-flow reactor. If the reaction to the desired product has a lower order than the byproduct reaction, use a continuous well-mixed reactor. 

The process options reflect the broad range of compositions and gas volumes that must be processed. Both batch processes and continuous processes are used. Batch processes are used when the daily production of sulfur is small and of the order of 10 kg. When the daily sulfur production is higher, of the order of 45 kg, continuous processes are usually more economical. Using batch processes, regeneration of the absorbant or adsorbant is carried out in the primary reactor. Using continuous processes, absorption of the acid gases occurs in one vessel and acid gas recovery and solvent regeneration occur in a separate reactor. 

Most aroma chemicals are relatively high boiling (80—160°C at 0.4 kPa = 3 mm Hg) Hquids and therefore are subject to purification by vacuum distillation. Because small amounts of decomposition may lead to unacceptable odor contamination, thermal stabiUty of products and by-products is an issue. Important advances have been made in distillation techniques and equipment to allow routine production of 5000 kg or larger batches of various products. In order to make optimal use of equipment and to standardize conditions for distillations and reactions, computer control has been instituted. This is particulady well suited to the multipurpose batch operations encountered in most aroma chemical plants. In some instances, on-line analytical capabihty is being developed to work in conjunction with computer controls. 

With a bulk process, resole resins, in neat or concentrated form, must be produced in small batches (ca 2—9.5 m ) in order to maintain control of the reaction and obtain a uniform product. On the other hand, if the product contains a large amount of water, such as Hquid plywood adhesives, large reactors (19 m ) can be used. Melt-stable products such as novolaks can be prepared in large batches (19—38 m ) if the exotherms can be controlled. 

Details for the nonsolvent batch oleum sulfonation process for the production of BAB sulfonic acid have been described, including an exceUent critique of processing variables (257). Relatively low reaction temperatures (ca 25—30°C) are necessary in order to obtain acceptable colored sulfonate, which requires refrigerated cooling (Table 9, example D). 

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