Plant base case

The Smith-Brinkley Method can therefore be used to generate a hand base case beginning with either a heat and material balanced plant case, a rigorous computer solution of a plant case, or computer solution of a design case. Once the hand base case is established, alternate cases can be done by hand (or small computer having limited core) using the Smith-Brinkley Method. 

After the base case is digested and accepted by the designer as valid, various modification cases can be obtained. Because the base case and each modification case is presented in its best light (at the optimum plant operation for that case), bias between cases is eliminated. Therefore, the designer can compare cases on the same basis. 

By necessity, herbivores have evolved GIT and systemic compensatory mechanisms that allow them to subsist on plant-based diets that have limited nutrient quality and include phytochemicals. Still, herbivores remain susceptible to some of the anti-nutrient and toxic phytochemicals. For example, several herbivores are sensitive to the phytotoxins associated with autumn crocus, which include colchicine (Yamada et al, 2000). As a consequence, herbivores tend to select species and portions of plants based on a combination of nutrient quality and concentrations of phytochemicals (Yeager et al, 1997), and this has an impact on habitat selection and plant ecology (Duncan and Gordon, 1999). Carnivorous species have not been under selective pressure to develop similar compensatory mechanisms, generally have only limited abilities to subsist on plant-based diets, and in many cases are less tolerant of phytochemicals. 

The value of the extra chlorine recovered will pay for the membranes in about nine months. Addition of operating costs still gives an attractive pay-out. However, the base case for Table 7.4 assumes that nothing is done to handle the chlorine issuing from liquefaction. This is not an option. The real question is how the membrane process compares with the alternatives, and this is the subject of Table 7.5. The basis assumed is an 800 tonnes per day plant with gas composition 93.16% CI2,2.40% O2, 3.82% N2, 0.37% CO2, and 0.25% H2. The table covers costs only. Product values are highly sensitive to local conditions and are not included. In all cases, the membrane option is based on the field test in order to give the most reliable numbers available. Technological development will improve the case for the use of membranes. 

Figure 9. Relative carbon number yields in C5-265°F gasoline versus base case in pilot plant test.

Comparing results for the cases where allocation of allowances is contingent on plant existence during the 3-5-year allocation period with the base case (auction or one-off grandfathering), the... 

This book is the first to summarize the biomonitoring of heavy metals in terrestrial ecosystems using plants. Based on a sizeable collection of case studies drawn from diverse geobotanical areas throughout the world, the book covers chemical and analytical aspects, processes of bioaccumulation as well as geobotanical and biogeochemical prospecting. 

The raw materials, utilities, and by-products were changed directly by the ratio of plant capacity. The hydrogen price was calculated using the same procedure as in the base case. Variations between the 0.6 and 0.7 power factor have only a small effect on hydrogen price. The assumption of many modules for electrolysis suggests a higher exponent. 

Figure 6 shows the sensitivity of hydrogen price to feedstock price, all plotted on the same scale. It should be noted that the "feedstock for electrolysis is electric power, not primary fuel, so that capital costs and inefficiencies associated with power generation are included in the raw material cost. The circles on this figure represent the base case for our calculations and reflect approximately realistic values for raw material costs for large-scale plants in 1979. 

Figure 7 shows the sensitivity of hydrogen price to variations in plant cost, and also exhibits the considerable differences in plant cost assumed for the base case — believed to be reasonable... 

Figure 9 shows how the cost of hydrogen may be expected to change as the scale of the plant is reduced from the 100 X 106 SCF/day base case. Some subjective judgments were made as to the relative scale factors for electrolysis and the other processes. Electrolysis scales down more favorably primarily because the electric generating plant is not included in the system. 

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