This paper develops a new simulation model for crystal size distribution dynamics in industrial batch crystallization. The work is motivated by the necessity of accurate prediction models for online monitoring purposes. The proposed numerical scheme is able to handle growth, nucleation, and agglomeration kinetics by means of the population balance equation and the method of characteristics. The...

In industrial fed-batch cultivations it is often necessary to control substrate concentrations at a low level to prevent the production of overflow metabolites and thus optimize the biomass yield. A new method for on-line monitoring and fed-batch control based on fluorescence measurements has been developed. Via instantaneous in situ measurements and multivariate data analysis a chemometric mod...

Cephalosporin C (CPC), a β-lactam antibiotic, is starting molecule for industrial production of semi synthetic cephalosporins. CPC fermentation has been carried out in Air Lift Reactor (indigenously made up of borosilicate glass) in different fermentation modes i.e., batch and fed batch modes using a mold Acremonium chrysogenum (synn. Cephalosporium acremonium). A definite correlation exists be...

The same kind of n jobs are processed one by one sequentially by a single machine and any number k of them may be processed as a batch. A setup time is necessary before the processing of the first job in a batch. The completion times of all the jobs in a batch are the same as the completion time of the last job in the batch and the processing time of the batch is the sum of a setup time and k t...

Batch processing machines are commonly used in wafer fabrication, kilns, and chambers used for environmental stress screening (ESS). This paper proposes two models to schedule batches of jobs on two machines in a flow shop. A set of jobs with known processing times and sizes has to be grouped, to form batches, in order to be processed on the batch processing machines. The jobs are nonidentical ...

A batch machine is a machine that can process a number of jobs simultaneously as a batch, and the processing time of a batch is equal to the longest processing time of the jobs assigned to it. In this paper we present a polynomial time approximation scheme (PTAS) for scheduling a batch machine to minimize the total completion time with job release dates. Also, we present a fully polynomial time...

In this paper, we extend the classical Variable Size Bin Packing Problem (VS-BPP) by adding time features to both bins and items. Specifically, the bins act as machines that process the assigned batch of items with a fixed processing time. Hence, the items are available for processing at given times and are penalized for tardiness. Within this extension we also consider a stochastic variant, wh...

On-line analytical processing (OLAP) and data warehousing technologies has been accepted in business community as indispensable tools of effective data usage. Contemporary industrial process are as complex as the ones in the business field. OLAP techniques may be utilized in management of industrial process once there are implementations satisfying strident timing requirements of industrial pro...

This paper presents a case study of an implementation of a new method for Production Leveling designed for batch production. It includes prioritizing criteria of products and level production plan. Moreover, it was applied on a subsidiary of a multinational enterprise located on Brazil, which manufacturing processes comprise batch production in a make-to-stock policy. Regarding a qualitative as...

This paper describes the use of timed Condition/Event (C/E) systems, a real-time extension of the C/E system framework introduced by Sreenivas and Krogh, for building models of chemical plants in a modular fashion and as a basis for the model-based analysis of their discrete control. The approach is illustrated by applying it to the safety control logic of a laboratory batch process.