Читать книгу Process Intensification and Integration for Sustainable Design - Группа авторов - Страница 47

Next a few specific cases are considered as shown in Table 2.11. The heating value price affects both the methane and the feedstock price. A higher price for heating value increases both the methane sales prices (which increases potential profitability) and increases the feedstock price (which decreases potential profitability). A sensitivity analysis is used to show which of these counteracting effects is more significant.

Table 2.11 Description of Cases 1–3 for sensitivity analysis.

	Case 1	Case 2	Case 3
Heating value	−1 Standard deviation	Average	+1 Standard deviation
NGL prices	Average	Average	Average

The results in Figure 2.13 show the process is more profitable at lower heating value prices. This means the methane is being sold for less; however this reduction in revenue is more than offset by the reduction in feedstock cost. A further calculation shows, assuming average NGL prices, the heating value price must be less than US$5.42 per MMBtu to achieve an ROI of more than 10%.

Figure 2.13 Results for Cases 1–3 for the sensitivity analysis.