Economic potential

At each level of the design the feasibility of alternatives may be evaluated by means of an economic potential (EP). This index has the significance of an added value representing the difference between earnings and expenses on yearly basis. Since at the input/output level the process configuration is not known, only material costs, including auxiliary resources and ecological costs, are considered  

EPI/0 = Product value + Byproduct value - Raw materials costs  

EPI/0 is useful for assessing the feasibility of alternative chemistries and sources of raw materials before undertaking a more detailed flowsheet development. Clearly, the economic potential should be largely positive to accept further reductions when the capital and operation costs are taken into account. 

Therefore, the economic potential at the I/O level could be seen merely as a tool for selecting the chemical route, and at the same time for setting targets when purchasing raw materials. As a rule of thumb, the ratio of selling prices of products to the purchasing prices of raw materials should be a minimum of two when the payback time of the total capital investment is greater than five years. Preferably, this ratio should be about three for a payback time of three years [3]. More accurate calculations may be carried out easily by means of profitability analysis tools. 

Processing costs = Equipment costs/Payback time + Cost of utilities  

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Solution Decisions can be made based on the economic potential of the process (see App. A). At this stage, the best we can do is to define the economic potential (EP) as... 

Paths 1 and 3 are clearly not viable. Only path 2 shows a positive economic potential when the byproduct HCl can be sold. In practice, this might be quite difficult, since the market for HCl tends to be limited. 

Considering raw materials costs only, the economic potential (EP) of the process is defined as... 

The minimum selectivity which can be tolerated is given when the economic potential is just zero ... 

Optimization of the system can be carried out by minimizing a cost function or maximizing economic potential EP defined by (see App. A)... 

Plots of economic potential versus reactor conversion allow the optimal reactor conversion for a given flowsheet to be identified (Fig. 8.2). Although this approach allows the location of the optimum to be found, it does not give any indication of why the optimum occurs where it does. 

Rgure 8.2 A plot of economic potential versus conversion shows where the optimum is, but why does the optimum occur where it is ... 

All these variables must be varied in order to minimize the total cost or maximize the economic potential (see App. A). This is a... 

The preceding definitions of economic potential and total annual cost can be simplified if it is accepted that they will be used to compare the relative merits of difierent structural options in the flowsheet and difierent settings of the operating parameters. Thus items which will be common to the options being compared can be neglected. 

Because of the large price differential between propane and propylene, which has ranged from 155/t to 355 /1 between 1987 and 1989, a propane-based process may have the economic potential to displace propylene ammoxidation technology eventually. Methane, ethane, and butane, which are also less expensive than propylene, and acetonitrile have been disclosed as starting materials for acrylonitrile synthesis in several catalytic process schemes (66,67). 

J. W. Savage and D. Bailey, Economic Potential of the New Sodium Minerals Found in the Green Piver Formation, presented at 61st Annual Meeting of the American Institute of Chemical Engineers, Los Angeles, Calif., Dec. 1—5, 1968. 

Cyclization. Constmction of ben2otrifluorides from aHphatic feedstocks represents a new technique with economic potential. For example, l,l,l-trichloro-2,2,2-trifluoroethane [354-58-5] and dimethyl itaconate [617-52-7] form 4-methoxy-6-trifluoromethyl-2JT-pyran-2-one [101640-70-4] which is converted to methyl 3-(trifluoromethyi)ben2oate [2557-13-3] ixh. acetjdene or norbomadiene (125). 

Pyrolytic routes to hexafluorobenzene have also attracted attention but have not been commercialized. Pyrolysis of tribromofluoromethane [353-54-8] CBr F, at 630—640°C in a platinum tube gives hexafluorobenzene in 55% yield (251—253). The principal disadvantage of this process is the low weight yield of product 90% of the costly CBr F that is charged is lost as bromine. Of economic potential is the related copyrolysis of dichlorofluoromethane [754-34-0] and chlorofluoromethane [593-70-4] (254,255). 

G. M. Reistad, paper presented at the Proceedings of the 2nd UN Symposium on the Development and Use of Geothermal Resources, Vol. 1, Lawrence Berkeley Laboratory, San Erancisco, 1975, pp. 2155—2164 "Analysis of the Economic Potential of Solar Thermal Energy to Provide Industrial Process Heat," U.S. ERDN Contract, EY-No-C-02-2829, Intertechnology Corp., 1977. 

Deep-sea manganese nodules represent a significant potential mineral resource. Whereas the principal constituent of these deposits is manganese, the primary interest has come from the associated metals that the nodules can also contain (see Ocean rawmaterials). For example, metals can range from 0.01—2.0% nickel, 0.01—2.0% copper, and 0.01—2.25% cobalt (12). Recovery is considered an economic potential in the northwestern equatorial Pacific, and to a lesser degree in the southern and western Pacific and Indian Oceans (13—18). 

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. 

As with all of die processes described, drese are first studied in detail in the laboratoty with an industrial application as dre objective. Those processes which pass the criterion of economic potential are used in a pilot plant smdy, and dretr, if successful, at the production level which must be optimized. The materials which are produced are mainly, in the present instance, for application in the elecU onics industry where relatively high costs are acceptable. It will be seen drat the simple kinetic theory of gases is adequate to account for dre rates of these processes, and to indicate the ways in which production may be optimized on dre industrial scale. 

Determine the optimal steam ratio (kg steain/kg ethylbenzene) that should be used in the styrene reactor in order to maximize the economic potential of the process. 

Given a reactor of known size and functionality, and a desired product along with its flowrate, synthesize an overall chemical reaction that features maximum economic potential while complying with all environmental and thermodynaimc constraints. 

In order to generate a candidate EAR, one should consider potential raw materials and by-products, satisfaction of stoichiometric conditions, assurance of thermodynamic feasibility, and fulfillment of environmental requirements. These issues can be addressed by employing an optimization formulation to identify an overall reaction that yields the desired product at maximum economic potential while satisfying stoichiometric, thermodynamic, and environmental constraints. For a more detailed description of this optimization program, the reader is referred to Crabtree and El-Halwagi (1994). 

This reaction has an economic potential of 40.05 million per year. An advantage of the optimization-based approach to synthesizing EARs is its ability to generate... 

Oxygen -I- Methyl Formamide-1- a—Naphthol = Carbaryl + Water (12.2) which yields an economic potential of 39.99 million per year, and... 

The rig selection will dictate the basic layout of the pad. Based on the necessary area needed to support its functions, ancillary equipment may be added in space conservative measures. In addition to the placement of various stationary rig site components, other operations such as logging, trucking and subsequent completion operations must be provided for. The most environmentally sensitive design will impact the least amount of area, and in that it will be the most economic. Potential pad sites and access routes should be laid out on a topographic map prior to the actual survey. At this time, construction costs can be estimated and compared. Figure 4484 shows such a layout. The cost of building a location includes the cost of reclamation such as any remediation. 

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