Optimization of operating conditions

Operating conditions (or modes) have already been defined as part of service conditions which affect ageing processes. Periodic evaluation of operational experience may reveal the need to change operating conditions such as operation mode, core arrangements and chemical parameters of fluid. 

The frequency of inspections is also a parameter which requires optimization. Too high a frequency of inspection and maintenance work or tests may also accelerate ageing and an assessment of this effect is required. 

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While process design and equipment specification are usually performed prior to the implementation of the process, optimization of operating conditions is carried out monthly, weekly, daily, hourly, or even eveiy minute. Optimization of plant operations determines the set points for each unit at the temperatures, pressures, and flow rates that are the best in some sense. For example, the selection of the percentage of excess air in a process heater is quite critical and involves a balance on the fuel-air ratio to assure complete combustion and at the same time make the maximum use of the Heating potential of the fuel. Typical day-to-day optimization in a plant minimizes steam consumption or cooling water consumption, optimizes the reflux ratio in a distillation column, or allocates raw materials on an economic basis [Latour, Hydro Proc., 58(6), 73, 1979, and Hydro. Proc., 58(7), 219, 1979]. 

Based on a detailed mathematical model, one can make computer simulations of the behaviour of various reactor types. Optimization of operating conditions and design parameters can be done for each reactor type. Downstream equipment should also be taken into account since the cost of product isolation and purification can heavily influence the final choice of all equipment items. A proper combination of investment and operating costs is used as the... 

Vaisanen, A. and A. Hander. 2006. Optimization of operating conditions of axially and radially viewed plasmas for the determination of trace element concentrations form ultrasound-assisted digests of soil samples contaminated by lead pellets. Anal. Chim. Acta 570 93-100. 

The development of a commercially viable enzyme process for the production of ECB nucleus was achieved by improving the ECB and ECB deacylase fermentation processes and the bioconversion processes. Increased yields in the fermentation processes were achieved through linked programs for strain improvement and fermentation development. The bioconversion process was improved by the choice of substrate and enzyme conditions and subsequent optimization of operating conditions. An economic model was used to decide where development resources should be focused. 

Dilute-acid hydrolysis is therefore the main choice for the hydrolysis of hemicellulose to monosaccharides once it is a fast and efficient method (19). However, a careful optimization of operational conditions used for hydrolysis is important to ensure high monosaccharide recovery and minimize coformation of microbial inhibitors. 

It should be noted that the optimization problems solved for levels 2 and 3 begin to merge as the plantwide optimization begins to set targets for the unit operations in many process units. This large-scale, frequent optimization of operating conditions is known as real-time optimization (RTO). RTOs are run approximately every 30 minutes to 1 hour, with the resulting optimal setpoints downloaded to model predictive controllers (MPC). 

The attempts that have been made to utilize true chemometric optimization of operating conditions in CEC are unclear in most of the studies done utilizing CEC. This has been done for many years in GC and HPLC, as well as in CE, but there are no obvious articles that have appeared which have utilized true chemometric software approaches to optimization in CEC [57-59]. It is not clear that any true method optimization has been performed or what analytical figures of merit were used to define an optimized set of conditions for biopolymer analysis by CEC. It is also unclear as to why a specific stationary phase (packing) was finally selected as the optimal support in these particular CEC applications for biopolymers. In the future, it is hoped that more sophisticated optimization routines, especially computerized chemometrics (expert systems, theoretical software, or simplex/optiplex routines) will be employed from start to finish. 

V.A. Papavassiliou, J.A. McHenry, E.W. Corcoran, H.W. Deckman and J.H. Meldon, High flux asymmetric catalytic membrane reactors. Optimization of operating conditions. Paper presented at the 1st International Workshop on Catalytic Membranes, September 1994, Lyon-Villeurbanne, France. 

Gas and liquid fuel burners are characterized by relatively complicated geometry. In order to save money on design optimization and optimization of operating conditions of burners, there has been lately an effort to use various simulations and empirical models obtained... 

Optimization of operating conditions is also made with reference to the final target The choice of whether to pressurize the feed stream or to use vacuum or a sweep gas on the permeate side, depends on assodated costs and on the specific case considered. For example, if the feed stream is already available in the plant at the pressure needed, the permeate can operate at atmospheric pressure. Otherwise, the energy required to apply vacuum or to pressurize the feed must be compared to the costs of the sweep gas as well as the costs related to the additional separation of the diluted permeate. 

Bhide, B.D. and S.A. Stem, Membrane processes for the removal of acid gases from natural gas. I. Process configurations and optimization of operating conditions. Journal of Membrane Science, 1993. 81(3) UFJ-Til. 

Optimization of operational conditions focusing on corrosion issues ... 

This text is designed to acquaint and orientate newcomers with TA by providing a concise introduction to the basic principles of instrument operation, advice on sample preparation and optimization of operating conditions and a guide to interpreting results. The text deals with DSC and DTA in Chapters 2 and 3. TG is described in Chapter 4. In Chapter 5 the application of these TA techniques to polymer science is presented. Other TA techniques are briefly described for completeness in Chapter 6. The Appendices include a glossary of TA terms, a survey of standard reference materials and TA conversion tables. 

One of the more reliable study approaches consists in effective integration of theory and practice the results can be interesting from an academic point of view for the understanding of phenomena and from an industrial point of view in terms of technology and optimization of operating conditions. 

We have employed some rather simple kinetics, conventional pressure drop and heat transfer formulae, ideal film calculations and some basic empirical correlations to develop a reactor model that quite adequately relates the cracking severity of small bench scale units and commercial furnaces. Thus, evaluation of feedstocks using the bench unit has significantly more meaning. Optimization of operating conditions can be calculated for various cracking coil configurations. 

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