Chemical processes economic drivers

Adequate information must be available for installed costs of piping and pumping equipment. Although suppliers quotations are desirable, published correlations may be adequate. Some data and references to other published sources ate given in Chapter 20. A simplification in locating the optimum usually is permissible by ignoring the costs of pumps and drivers since they are essentially insensitive to pipe diameter near the optimum value. This fact is clear in Example 6.8 for instance and in the examples worked out by Happel and Jordan (Chemical Process Economics, Dekkcr, New York, 1975). 

The primary driver ia sulfur recovery appHcations is not economic potential, but rather environmental regulation. The capital investment required for sulfur recovery faciHties is significant. Increasing pressure to maximize recovery and throughput at minimum investment is constantiy being brought to bear on the chemical process iadustry. 

The growing nse of more complex PAT (versus the historically used simple univariate sensors such as pressure, temperature, pH, etc.) within manufacturing industries is driven by the increased capabilities of these systems to provide scientihc and engineering controls. Increasingly complex chemical and physical analyses can be performed in, on, or immediately at, the process stream. Drivers to implement process analytics include the opportunity for live feedback and process control, cycle time reduction, laboratory test replacement as well as safety mitigation. All of these drivers can potentially have a very inunediate impact on the economic bottom line, since product quality and yield may be increased and labor cost reduced. 

Three important economic drivers can also bring significant potential benefits for the environmental impact of chemical processes ... 

In a chemical plant the capital investment in process piping is in the range of 25-40% of the total plant investment, and the power consumption for pumping, which depends on the line size, is a substantial fraction of the total cost of utilities. Accordingly, economic optimization of pipe size is a necessary aspect of plant design. As the diameter of a line increases, its cost goes up but is accompanied by decreases in consumption of utilities and costs of pumps and drivers because of reduced friction. Somewhere there is an optimum balance between operating cost and annual capital cost. 

The chemical industry is broad, and it would not be possible to adequately cover all the areas here. However, some representative examples illustrate the earlier concepts and provide incentive for future work. The solvents presently used in chemical reactions and processes were chosen based upon on performance criteria, including optimal yield, chemical reactivity and selectivity. Each industry or chemical sector must determine how the regulatory, economic and technological drivers affect their solvent supply in the near and far term, and motivate them to use green solvents. 

An answer to this question must begin with an economic comparison. Certainly the primary driver for greater domestic use of renewable feedstocks is cost because it will be the chemical industry that needs to be convinced of the value of renewables. That argument is only won by favorable economics. As shown in several studies, not all renewables-based materials are reasonable targets for biomass based processes, primarily for economic reasons (14). 

Acceptance of supercritical fluids for solvent replacement in the chemical industry will probably require economic as well as environmental drivers. A key con nent of research in supercritical fluids must therefore be to identify and quantify the advantages (e.g. faster rates, higher selectivities) of carrying out chemicd transformations in supercritical CO2 rather than in conventional solvents. The development of other reactions in supercritical CO2 with superior rates and selectivities sufficient to justify the costs of implementing SCF-based production processes is essential to resizing pollution prevention by this route. 

Business and process drivers are required to set targets to be met by the plant design. The business drivers identified at the start of the methodology, which are the economic reasons why it is desirable to intensify the process, should be reviewed to keep a clear idea of the overall aims of the project. Process drivers are those characteristics of, in this particular example, the chemical reaction scheme that determine the required operating conditions within, and performance of, reactor equipment to allow the process to run at its most efficient rate. A process driver example is the rate of heat release from a reaction determining the heat transfer capability required of the equipment. 

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