A biorefinery process called "Biofine" has been presented in the recent past
(Kamm and Kamm, 2004). It is a biomass-based process route making use of acid
hydrolysis and dehydration subprocesses and esterification with ethanol to
ethyl levulinate (EL) (an ester of levulinic acid and ethanol). By-products
considered are power and formic acid (FA). The production of EL is \(133
\mathrm{kt}\). year \(^{-1}\). The capital cost is 150 million US\$ (consider
linear depreciation in 10 years). Table \(15.8\) gives an overview of the prices
of the raw materials and by-products. In addition, the water supply costs are
US\$ 500,000/year. Regarding labor, there are 17 operators per shift working
at a salary of US\$ \(20 / \mathrm{h}\) and two supervisors per shift working at
a salary of US\$ \(24 / \mathrm{h}\). Assume an ROI of \(15 \%\). For other costs,
take the guidelines given in this chapter (Table 15.6).
a. Calculate the cost and return price in US $\$$ per tonne EL produced.
b. What is the price in US \$ per GJ HHV? (hint: calculate the heat of
combustion of EL).
c. Is it possible to produce the required ethanol in the process itself?
TABLE 15.8 Overview of costs, yields of by-products, and material amounts for
the "Biofine"' process
$$
\begin{array}{lll}
\text { Raw material/utility/by-product } &{\text { Amount }} & \text { Price
in US\$ } \\
\hline \text { Feedstock } & 350 \mathrm{kt} \cdot \mathrm{year}^{-1} & 40
\cdot \mathrm{t}^{-1} \\
\text { Sulfuric acid } & 3.5 \mathrm{kt} \cdot \mathrm{year}^{-1} & 100 \cdot
\mathrm{t}^{-1} \\
\text { Caustic soda } & 0.5 \mathrm{kt} \cdot \mathrm{year}^{-1} & 120 \cdot
\mathrm{t}^{-1} \\
\text { Ethanol } & 35 \mathrm{kt} \cdot \text { year }^{-1} & 350 \cdot
\mathrm{t}^{-1} \\
\text { Hydrogen } & 0.12 \mathrm{kt} \cdot \mathrm{year}^{-1} & 1500 \cdot
\mathrm{t}^{-1} \\
\text { Ash disposal } & 17.5 \mathrm{kt} \cdot \mathrm{year}^{-1} & 35 \cdot
\mathrm{t}^{-1} \\
\text { Power exported } & 3.1 \mathrm{MW} & 60 \mathrm{MWh}^{-1} \\
\text { Formic acid sold } & 38.5 \mathrm{kt} \cdot \mathrm{year}^{-1} & 110
\cdot \mathrm{t}^{-1} \\
\hline
\end{array}
$$