Economic object

J. Santucci and J. J. Taylor, Safety, Technical and Economic Objectives of the Electric Power Institute s didvancedTight-Water Reactor Programme, lAEA-SM-332/11.1, Proceedings of International Symposium on Advanced Nuclear Power Systems, Seoul, Korea, Oct. 1993. 

WELLS, G. L. (1973) Process Engineering with Economic Objective (Leonard Hill). 

In addition to the economic objective of savings for public health care funds, the regulation of the Spanish pharmaceutical sector pursues other goals, both economic and social. Thus, from a social welfare viewpoint, it is important to bear in mind the repercussions of regulation on the health status of the... 

In an era of escalating health care costs, "inputs" to the production of health care, such as pharmaceuticals, physician visits, laboratory/diagnostic services, and hospital care, are often viewed in isolation from each other as if one sector of the health care economy can be optimized independent of the others. When cost containment is the primary economic objective, a shortterm, risk-averse decision rubric emerges. 

The results received form the optimization using inherent safety as the objective function are somewhat different compared to those calculated with an economic objective function earlier (Hurme, 1996). With the inherent safety objective function the simple distillations were favoured more than with the economic function. Exceptions are cases where the extractive distillation could improve separation very dramatically. This is because in simple distillations only one column is required per split, but in extractive distillation two columns are needed, since the solvent has to be separated too. This causes larger fluid inventory since also the extraction solvent is highly flammable. The results of the calculation are well justified by common sense, since one of the principles of inherent safety is to use simpler designs and reduce inventories to enhance safety. 

Appendix B explains ways of estimating the capital and operating costs, leading to the coefficients in economic objective functions. 

Heinzle, E., Weirich, D., Brogli, F., Hoffmann, V., Roller, G., Verduyn, M.A. and Hungerbuhler, K. (1998) Ecological and Economic Objective Functions for Screening in Integrated Development of Fine Chemical Processes. 1. Flexible and Expandable Framework Using... 

The objective function can assume different representation with regards to the system under study. A commonly used objective of an industrial process is to maximize profit or to minimize the overall costs. The former is adopted in this work. In this model, the whole refinery is considered to be one process, where the process uses a given petroleum crude to produce various products in order to achieve specific economic objectives. Thus, the objective of the optimization at hand is to achieve maximum profitability given the type of crude oil and the refinery facilities. No major hardware change in the current facilities is considered in this problem. The... 

The economic objective in the model can either be represented as operating cost minimization or added-value maximization. In the case of added-value maximization, product prices are subtracted from the cost of feedstocks for each process. If PrCpet is the price of chemical cp, the added-value objective function can be represented as ... 

At a site in Quebec, Canada, the technology met project economic objectives with cost of remediation totaling 75 per metric ton of treated material. The total cost for the project was 200,700. Costs are in Canadian dollars (D14835Q, p. 1). 

The British sphere in Malaya, and the French in the Mekong basin, were the outcome of purely economic objectives along real or imagined trade routes to China. The British sought trading bases in the Malacca Straits area for the collection of tropical trade goods for China the French... 

The economic objective function to be minimized is the cost, which combines the capital costs associated with building the column and the utility costs associated with operating the column. The form for the capital cost of the column depends upon the vapor boilup, the number of trays, and the column diameter... 

The scope of a model is typically chosen so that it is sufficient to envelop the feeds, product, and utilities to be able to have a meaningful economic objective function. Sometimes it is preferable to include upstream or downstream facilities even in a simple form to be able to use actual feed, product, and utility costs rather than transfer prices. 

Many polymer reactions, for example, are highly exothermic, so the temperature control concepts outlined in this book must be applied. At the same time, controlling just the temperature in a polymer reactor may not adequately satisfy the economic objectives of the plant, since many of the desired polymer product properties (molecular weight, composition, etc.) are created within the polymerization reactor. These key properties must be controlled using other process parameters (i.e. vessel pressure in a polycondensation reactor or chain transfer agent composition in a free-radical polymerization reactor). 

This reactor-column process has several degrees of freedom that can be adjusted to satisfy some economic objective. The most important is the size of the reactor. The smaller the reactor, the larger the column and the recycle flow. 

We start by studying the steady-state design and economics of a process with a single adiabatic reactor. The design considers the entire plantwide process reactor, heat exchangers, gas recycle compressor, preheat furnace, condenser, and separator. The economic objective function is total annual cost, which includes annual capital cost (reactor, catalyst, compressor, and heat exchangers) and energy cost (compressor work and furnace fuel). 

This winemaking process is applicable to a range of wine styles. In addition, its flexibility allows winemakers to adjust it to his/her particular needs and economical objectives. 

Control objectives for a chemical process originate from certain regulation tasks (i.e. product quality control, material balance control, safety, environmental regulations, etc.) and economic objectives (i.e. optimizing the economic performance). Such a classification of control objectives automatically formulates the different design activities for the regulatory and optimizing control structures. 

A process-synthesis problem can be formulated as a combination of tasks whose goal is the optimization of an economic objective function subject to constraints. Two types of mathematical techniques are the most used mixed-integer linear programming (MILP), and mixed-integer nonlinear programming (MINLP). 

Boston (75) added a middle loop to allow for column specifications and constraints. The arrangement of equations in the inner loop, where the solution of the MESH variables occurs, allows for only a few control or specified variables, such as fixed reflux ratio and product rates, The middle loop adjusts the control variables to meet the specifications. The middle loop can be built as an optimization method with process specification equations and economic objectives and constraints. 

The catalytic functionalization of aromatic C-H bonds to form C-C bonds under mild conditions is an attractive economic objective. An efficient hydroarylation reaction between alkynes and alkenes to form C-C bonds has been described.43 The reactions are catalysed by Aum complexes under mild and even solvent-free conditions at ambient temperature. 

Chapter 16 provides guidance relating to the choice of industrial bioseparation equipment that is available and the issues that must be taken into account when selecting a suitable system to meet both technical and economic objectives. 

We can draw a very useful general conclusion from this simple binary system that is applicable to more complex processes changes in production rate can be achieved only by changing conditions in the reactor. This means something that affects reaction rate in the reactor must vary holdup in liquid-phase reactors, pressure in gas-phase reactors, temperature, concentrations of reactants (and products in reversible reactions), and catalyst activity or initiator addition rate. Some of these variables affect the conditions in the reactor more than others. Variables with a large effect are called dominant. By controlling the dominant variables in a process, we achieve what is called partial control. The term partial control arises because we typically have fewer available manipulators than variables we would like to control. The setpoints of the partial control loops are then manipulated to hold the important economic objectives in the desired ranges. 

Most of these valves will be used to achieve basic regulatory control of the process (1) set production rate, (2) maintain gas and liquid inventories, (3) control product qualities, and (4) avoid safety and environmental constraints. Any valves that remain after these vital tasks have been accomplished can be utilized to enhance steady-state economic objectives or dynamic controllability (e.g., minimize energy consumption, maximize yield, or reject disturbances). 

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