Process monitoring and analysis

Process monitoring and analysis a. Virtual sensors Least squares Nonlinear, physically based, steady state, or empirical... 

The Moldflow Shotscope process monitoring and analysis system collects critical data in real time from injection molding machines on the factory floor, then records, analyzes, reports, and allows access to the information for use in critical decision making. 

The design of a process monitoring and analysis system (note, from here on we will use the term PAT system to refer to such a system) is a step-wise procedure involving the selection of critical process variables, followed by the selection and placement of suitable monitoring and analysis equipments, and finally, the coupling of the monitoring and analysis tools to a control system to ensure that the selected critical process... 

The extreme case of process monitoring and analysis is off-line analysis where the sample is acquired and then taken to a measurement laboratory, although the actual measurement system can be the same as the on-line or at-line system. Usually calibration will be performed using traditional analytical procedures. 

The process monitors and controllers typically also have the capabiUty for data logging, analysis, and display. This capabiUty has made on-line control of pilot plants, as well as commercial-scale processes, desirable. Pilot-plant appHcations for on-line control have been described (106), and the use of such systems for both monitoring and process diagnosis has been discussed (107). A number of commercially available process control programs that mn on microprocessors have been reviewed (108). Virtually all of them incorporate graphic display as an integral part of the interactive capabiUty of the program. 

The creation and analysis of process flow sheets has become much easier because of the availabihty of automated systems to draw and revise them. The goal of the use of the flow sheet as the input for process simulation and for process control is likely to be achieved reasonably soon. The use of interactive graphic displays for process monitoring and control is pervasive today. 

Leaks in process vessels and devices such as valves are a serious problem in many industries. A variation of vibration monitoring and analysis can be used to detect leakage and isolate its source. Leak-detection systems use an accelerometer attached to the exterior of a process pipe. This allows the vibration profile to be monitored in order to detect the unique frequencies generated by flow or leakage. 

Vibration Monitoring and Analysis Station Process plant... 

Davis, J. F., Bakshi, B., Kosanovich, K. A., and Piovoso, M. I., Process monitoring, data analysis and data interpretation, Proceedings, Intelligent Systems in Process Engineering, AIChE Symposium Series, 92(312), (1996a). 

The annual cost of the laboratory analyses required for process monitoring and quality control is a significant item in most modem chemical plants. The costs should be calculated from an estimate of the number of analyses required and the standard charge for each analysis, based on experience with similar processes. 

Real- Time Analysis for Pollution Prevention Analytical methodologies need to be further developed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances. 

The proper setting for variographic analysis is a set of 60 representative increments (this is a minimnm requirement, 100 samples is always preferable if possible, the minimum number of increments ever snc-cessfnlly snpporting an interpretable variogram is 42), in order to cover well the specific process variations to be characterized. It is important to select a 0niin that is smaller than the most probable sampling frequency likely to be used in rontine process monitoring and QC. It will be the objective of the data analysis to... 

Most hterature references to pharmaceutical primary process monitoring are for batch processes, where a model of the process is built from calibration experiments [110, 111]. Many of these examples have led to greater understanding of the process monitored and can therefore be a precursor to design of a continuous process. For example, the acid-catalysed esterification of butan-l-ol by acetic acid was monitored through a factorial designed series of experiments in order to establish reaction kinetics, rate constants, end points, yields, equilibrium constants and the influence of initial water. Statistical analysis demonstrated that high temperatures and an excess of acetic acid were the optimal conditions [112]. 

Environmental microbial monitoring and analysis of data by qualified personnel will permit the status of control to be maintained in clean rooms and other controlled environments. The environment should be sampled during normal operations to allow for the collection of meaningful data. Microbial sampling should occur when materials are in the area, processing activities are ongoing, and a full complement of operating personnel is on site. 

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