Batch process equipment cleaning

Often batch process equipment needs to be located inside buildings. This is usually the case when the process needs to be shielded from extreme heat/cold conditions, the elements, and/or needs to be kept sterile. This leads to the need to provide adequate building ventilation to avoid buildup of hazardous material due to leaks and other process emissions. When the operation of a process involves opening, cleaning, charging etc., point source ventilation may also need to be provided. 

Franks JW, Seiberling DA, inventors Electrol Specialities Company, assignee. Portable clean-in-place system for batch processing equipment. US patent 6,161,558. December 19, 2000. 

In both batch and continuous processes, it may be necessary to clean equipment to prevent contamination of new product. Materials used for equipment cleaning often cannot be recycled, leading to waste. 

Effective procedure training not only affects process safety, it also affects quality. Process yields, batch turnaround time, and equipment cleaning are all enhanced when the procedures are technically accurate and fully understood by the crews. 

For some processes, though they would not be classified as batch processes, the period of continuous production will be limited by gradual changes in process conditions such as, the deactivation of catalysts or the fouling of heat-exchange surfaces. Production will be lost during the periods when the plant is shut down for catalyst renewal or equipment clean-up, and, as with batch process, there will be an optimum cycle time to give the minimum production cost. 

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. 

A written record of major equipment cleaning, maintenance (except routine maintenance such as lubrication and adjustments), and use shall be included in individual equipment logs that show the date, time, product, and lot number of each batch processed. 

Standard operationg procedures (SOPs) incomplete, not current, or not available to the operators in the production area Batch production records incomplete, not recorded at time of operation, or not specific enough to document significant process steps Cleaning procedures not validated or not including all processing equipment and transfer implements (scoops, etc.)... 

Dedicating a piece of equipment to a single formulation in a batch process means that the equipment remains dormant between production runs. Cleaning after each run can be avoided if the materials left in the equipment do not deteriorate with time or corrode the internals. The cost penalties of underutilizing equipment must be outweighed by cleaning and waste-dispos-... 

To maximize productivity in a manufacturing operation, the amount of time that equipment is idle must be minimized. Therefore in ideal circumstances as soon as equipment has been suitably cleaned it is used to process the next batch. Processing subsequent batches will be delayed if the operations for the first batch have not been completed when the process stream from the second batch is ready. This situation creates a process bottleneck. 

Ideally, there should be one process for cleaning a piece of equipment or system. This will depend on the products being produced, whether the cleaning occurs between batches of the same product (as in a large campaign) or whether the cleaning occurs between batches of different products. 

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