A comparison of bottling alternatives in the pharmaceutical industry

This paper presents the results of a case study in a batch production facility for biological vaccines with possibilities for rework. The problem considered is that of finding the best bottling alternative for produced batches when these have to undergo several lengthy quality tests related to the foregoing production processes. Produced batches can be bottled directly after production when the results of these test are completely unknown, after some positive (intermediate) test results are known, or after all tests have been completed with positive results. When waiting in order to be bottled, a batch has to stay in the production tank. Alternatives that start the bottling process quickly after production have the advantages of a relatively low tank capacity requirement and of a relatively small flow time if all test results are positive. However, a produced batch can only be reworked as long as it has not been bottled. So fast bottling reduces the possibilities for rework and therefore reduces the production yield. We present performance measures for comparing the different alternatives and derive closed form expressions for them. We also present the results obtained for the considered case.