Feasibility study economic conditions

Note Students sometimes complain that a project is not feasible at this stage and should be abandoned. However, the design team may not be fully aware of external developments, e.g. anticipated oil price rises, shortages of key commodities, etc. If a project does not appear feasible, it may be necessary to complete the design study in readiness for possible market changes and more favourable economic conditions. In this situation, it is preferable to perform the detailed economic evaluation (see Chapter 6) in terms of the changes in raw materials costs, increase in product price, etc., necessary to make the project profitable and feasible, rather than as a detailed statement of loss per annum. 

This section deals with the economic evaluation of the conversion of mixed plastics waste (MPW) into synthetic crude (syncrude) oil and coprocessing of MWP with vacuum residue into syncrude. In their feasibility study, Ali and co-workers considered the process technology developed by Veba Oel AG of Germany the Veba Combi-Cracking (VCC) option for the processing of MPW [31], The process data and economic data were taken mainly from Dijkema and Stougie [32] and Huffman and Shah [33] for this study. All the cost data were translated to represent the economic analysis for Saudi Arabian conditions. 

The conditions for the long term storage of the (C)RM have to be determined as a conclusion from the preliminary feasibility studies or from the study of the stability. Conservative measures can be applied in case stability cannot be fully guaranteed (e.g. storage at a temperature lower than the lowest temperature for which no instability could be found). Such conservative measures must remain economically acceptable. 

Table 17.1 Conditions and results of earlier economic feasibility studies of manganese nodule mining...

Furthermore, although total removal of any one of the necessary conditions for a fire will absolutely prevent its occurrence, such stringent restrictions on industrial operations are seldom economically feasible. Industrial materials are, however, studied with a view to ascertaining just how much leeway there is, so that a compromise between absolute fire prevention and economy of operation may be reached. It is for this reason that, while we know how to prevent fires, they still do start, and why loss limitation is such an important part of industrial fire protection... 

This study concluded that processing of MPW with VR at a capacity of 200 000 ton/yr (80000 ton/yr MPW and 120000 ton/yr VR), is economically feasible for Saudi Arabian conditions. This capacity is adequate in view of the amount of MPW generated in Saudi Arabia. The internal rate of return (IRR) is about 14.6% with a payback period of 6.4 years and break-even capacity of 47.6%. Although profitability is not very attractive, the project is recommended to solve the waste disposal problem of both MPW and VR. Some assistance should be provided to operate these plants through environmental protection agencies. 

Although issues of catalyst activity, stability, and selectivity have not yet allowed such processes to be economically feasible, the Dow study provided a basis for development of these transformations on an industrial scale in the near future. With the price and availability of petroleum fluctuating rapidly, the use of plant-derived starting materials is especially attractive and, under the right conditions, ultimately a good example of green chemistry. 

In 1991, Vasserot et al. isolated a yeast strain Candida ntolischiana 35) which produced an extracellular (3-glucosidase with a wide substrate spectrum and that could function at low pH value [3]. This enzyme was successfully studied for its potential to liberate aroma-rich terpenes. Microbial p-glucosidases can be used industrially in one of two ways. Either purified enzyme or intact cells could be immobilized or free in solution. Candida species are generally not well-suited for direct use in these industrial processes, because they fail to grow under the conditions of use. For this reason, the alternative approach of using the enzyme is more desirable. However, in order to permitt the process to be economically feasible, increased quantities of... 

In 1979, Chem Systems , Inc. (1979) conducted preliminary study to investigate feasibility of a Petrochemical Industry in Alaska and potential of Pacific Rim, U.S. and Canadian markets for the products. This study recommended that such a petrochemical complex should concentrate on producing low and high density polyethylene, styrene, vinyl chloride and ethylene glycol. Apart from this study no other study has been done to investigate economics and market conditions. Lack of initiative and fear that such a petrochemical complex may not be feasible has caused delay in further studies and reduced the interest in this option. 

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