Process control strategies

Generic Control Strategies. The two generic strategies for process control are feedback and feedforward control. Most process control strategies are based on one or a combination of these strategies (1 3). 

Cascade control strategies are among the most popular and usehil process control strategies. Modem control systems have made thek implementation and operation both easier from the standpoint of operations personnel, and cost effective as they are implemented in software rather than hardwiring the connections. 

Implement sustainable real-time process control strategies... 

Economic Incentives for Automation Projects Industrial applications of advanced process control strategies such as MFC are... 

Risk based regulatory scrutiny that relates to the level of scientific understanding of how formulation and manufacturing process factors affect product quality and performance and the capability of process control strategies to prevent or mitigate risk of producing a poor quality product. 

Before such process control strategies can be implemented, either for... 

Discuss the process control strategy for the overall process and the instrumentation required. 

A risk analysis is not an objective by itself, but is one of the elements of the design of a technically and economically efficient chemical process [1]. In fact, risk analysis reveals the process inherent weaknesses and provides means to correct them. Thus, risk analysis should not be considered as a police action, in the sense that, at the last minute, one wants to ensure that the process will work as intended. Risk analysis rather plays an important role during process design. Therefore, it is a key element in process development, especially in the definition of process control strategies to be implemented. A well-driven risk analysis not only leads to a safe process, but also to an economic process, since the process will be more reliable and give rise to less productivity loss. 

Economic Incentives for Automation Projects Industrial applications of advanced process control strategies such as MPC are motivated by the need for improvements regarding safety, product quality, environmental standards, and economic operation of the process. One view of the economics incentives for advanced automation techniques is illustrated in Fig. 8-41. Distributed control systems (DCS) are widely used for data acquisition and conventional singleloop (PID) control. The addition of advanced regulatory control systems such as selective controls, gain scheduling, and time-delay compensation can provide benefits for a modest incremental cost. But... 

The advanced process control strategies that are most applicable to the optimization of the distillation process are usually based on white-box modeling, where the theoretical dynamic models are derived on the basis of the mass, energy, and momentum balances of this well-understood process. Although the optimization techniques described here can improve productivity and profitability by 25%, this goal will only be achieved if the distillation process is treated as a single and integrated unit operation and the variables, such as flows, levels, pressures, etc., become only constraints, and the controlled and optimized variables are productivity and profitability. 

Buckley, P. S. (1992). Process Control Strategy and Profitability. Instrument Society of America, Research Triangle Park, NC. 

Figure 11.3 Vinyl acetate process control strategy. 

Karuppiah L, Swedek B, Thothadri M, Hsu WY, Brezoczky T, Ravid A. Overview of CMP process control strategies. Proceedings of the 11th International CMP-MIC. 2006. p 45-54. 

Type of parts to be cleaned (e.g., size, complexity, porosity, loading density, pressure sensitivity) Production capacity Breadth of application Dimensions, fixturing and flow pattern within cleaning vessel process control strategy Parts per cycle and cycles per work period Number of different processes that must be performed by the system... 

Stephanopoulos, G., Johnston, J., and Lakshmanan, R., An intelligent system for planning plant-wide process control strategies. Journal A 29(3), 81 (1988). 

During early stages of drug candidate development, raw materials and isolated process intermediates may be included in the finished goods essential peak set until the appropriate analytical and process-control strategies are implemented. Once the appropriate controls are in place as the candidate approaches commercialization, it may be possible to eliminate some of these components from the component set. 

With this semi-quantitative explanation as a starting point, we ll now proceed to develop a quantitative model of particle growth and coalescence in terms of deposition conditions which can be used in a process control strategy. 

Integration of process control strategies into the sequencing problem including tiie consideration of tiie dynamic behavior of the system. 

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