Sequential batch process

Laboratory scale-up in single-mode reactors to produce gram amounts of material can be performed either by the above-mentioned sequential batch processing using various vessel sizes (up to 50 mL) or by employing CF or SF reaction cells (5-50 mL). Conversely, multimode instruments allow for parallel synthesis or applications in large batches up to 1 L total volume and even CF and SF approaches utilizing > 300 mL cells (see below). 

A very versatile polymeric scaffold for site-specific double PPM is poly( 1 -aceto-l-pentalluorophenoxycarbonyl-2-vinylcyclopropane) [poly(APVCP)] (see Scheme 8) [139]. In this case, the two-step modification is performed in a sequential batch process. Following aminolysis by treatment with various primary amines, the ketone can be converted in the presence of hydrazide or hydroxylamine derivatives. Fmthermore, the ketone can be reduced to the secondary alcohol, which is subsequently converted into the ester or carbamate through the use of different acyl halides and isocyanates. 

Process data for the same polymer recipe were analyzed for 50 noncon-secutive, sequential batches. As before, the data were preprocessed to remove outliers and sorted to reflect normal operation. The data are sampled at 1-minute intervals during production of each batch. Fillering and normalization of the data is done prior to analysis. The final polymer quality... 

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. 

Sandhya S, Padmavathy S, Swaminathan K et al (2005) Microaetophilic-aerobic sequential batch reactor for treatment of azo dyes containing simulated wastewater. Process Biochem 40 885-890... 

It is the objective of this paper to provide a comprehensive review of the state-of-the art of short-term batch scheduling. Our aim is to provide answers to the questions posed in the above paragraph. The paper is organized as follows. We first present a classification for scheduling problems of batch processes, as well as of the features that characterize the optimization models for scheduling. We then discuss representative MILP optimization approaches for general network and sequential batch plants, focusing on discrete and continuous-time models. Computational... 

Chapter 5 deals with steady-state data reconciliation problem, from both a linear and a nonlinear point of view. Special consideration is given, in Chapter 6, to the problem of sequential processing of information. This has several advantages when compared with classical batch processing. 

A recursive procedure is presented that exhibits some advantages over classical batch processing since it avoids the inversion of large matrices. It is shown that when only one equation is processed at a time, the inversion degenerates into the computation of the reciprocal of a scalar. Furthermore, this sequential approach can also be used to isolate systematic errors that may be present in the data set (Romagnoli and Stephanopoulos, 1981 Romagnoli, 1983). 

Constant-volume batch diafiltration is the most efficient process mode. Sequential batch diafiltration is a series of dilution-concentration steps. Continuous diafiltration practiced in one or more stages of a cascade system has the same volume turnover relationship for overall recoveries as sequential batch diafiltration. The residence time however is dramatically reduced. If recovery of permeable solids is of primary importance, the permeate from the last stage may be used as diafiltration fluid for the previous stage. This countercurrent diafiltration arrangement results in higher permeate solids at the expense of increased membrane area. 

Sequential batches that fail to meet product and process specifications... 

Various biological processes have been used with good results, including extended aeration/activated sludge, sequential batch reactors, and biofihn reactors. Anaerobic treatment has not been effective because of high sulfate levels. 

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