# Biodiesel and Biolubricant Production from Waste Cooking Oil: Transesterification Reactor Modeling
## 3 Results and Discussion
### Industrial Equipment, Reactor Design, and Economic Feasibility Study
#### 3.5.4 Economic Feasibility Study
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Step** & **Power, kW** & \begin{tabular}{c} **Daily Working** \\ **Time** \\ \end{tabular} & \
\begin{tabular}{c} **Yearly Energy** \\ **Consumption, kWh** \\ \end{tabular} &
\begin{tabular}{c} **Annual Cost,** \\ **\(\upxi\cdot\)y\({}^{-1}\)** \\ \end{tabular} \\ \hline Heating & 25.54 & 1.3 & 8632.52 & 1553.85 \\ Stirring & 22.25 & 2.51 & 14,520.35 & 2613.66 \\ Vacuum & 2.2 & 0.67 & 383.24 & 68.98 \\ Purification & 44 & 0.7 & 8008.00 & 1441.44 \\ Total & 91.87 & \(-\) & 31,544.11 & 5677.94 \\ \hline \hline \end{tabular}
\end{table} 
Table 15: Energy costs (related to a working year) of the WCO-based biodiesel and biolubricant production plant. whereas the total cost of the industrial equipment for biodiesel and biolubricant production was 88,248.8 \(\upxi\). Regarding the water cost, it can be considered as a direct cost, as water is used to wash the reactor and supply the boiler to produce steam (with estimates of 124.8 and 0.36 m\({}^{3}\), respectively); for the former, tap water is enough to carry out this task, whereas for the latter, distilled water is required, estimated at different costs per liter (1.97 and 940 \(\upxi\cdot\)m\({}^{-3}\), respectively). As a result, the total annual cost of the water was 588.02 \(\upxi\). To sum up, Table 17 indicates the annual costs for production and annual incomes. As observed, the annual gross profit was obtained as the difference between the income (because of the annual production of the biolubricant and glycerol, which would be used in glycerol steam reforming processes not requiring purification steps that could increase its production costs) and the annual production cost (because of the raw materials, energy, and water used). These costs have been estimated for this production process, without considering the machinery costs, salaries, or depreciation because of the service life of the equipment. The net profit can be calculated as 75% of the gross profit, resulting in 873,923.23 \(\upxi\). Finally, considering machinery costs and salaries, the final profit of the plant for the first year of operation was 694,856 \(\upxi\). As in the experimental section, the economic feasibility approach faces different challenges that should be considered, like price fluctuations, which are beset by the current \begin{table}
\begin{tabular}{c c} \hline \hline
**Equipment** & **Cost (VAT Included), \(\upxi\)** \\ \hline WCO container & 2660 \\ Methanol container & 235.95 \\ Recovered-methanol container & 179.95 \\ Sodium methoxide container & 179.95 \\ Glycerol container & 235.95 \\ TMP container & 1180 \\ Biolubricant container & 4500 \\ TBHQ container & 42.35 \\ Steam generator & 3194 \\ Vacuum pump & 2360.60 \\ Purifier & 4100 \\ Reactor & 33,741 \\ Stirrer & 35,639 \\ \hline \hline \end{tabular}
\end{table} 
Table 16: Machine costs for this study. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Arnual Production Costs** & \multicolumn{4}{c}{**Annual Income**} \\ \hline
**Production** & **Cost, \(\upxi\)** & **Product** & **Production, L-y\({}^{-1}\)** & **Selling Price, \(\upxi\cdot\)L \({}^{-1}\)** & **Annual Income, \(\upxi\)** \\ \hline Raw materials & 150,808.43 & Biolubricant & 446,424 & 2.89 & 1,290,165.36 \\ \cline{2-6} Energy & 5677.94 & & **Production, T-y\({}^{-1}\)** & **Selling price, \(\upxi\cdot\)T \({}^{-1}\)** & **Annual income, \(\upxi\)** \\ \cline{2-6} Water & 588.02 & Glycerol & 128.56 & 250 & 32,140 \\ \hline \multicolumn{6}{c}{**Annual Profit**} \\ \hline Total annual costs (production), \(\upxi\) & & & 157,074.39 \\ Total annual incomes, \(\upxi\) & & & 1,322,305.36 \\ Annual gross profit, \(\upxi\) & & & 1,165,230.97 \\ \hline \hline \end{tabular}
\end{table} 
Table 17: Annual costs and income for the designed biodiesel and biolubricant production plant, including the gross profit. unstable geopolitical scenario. Accordingly, prices related to electricity, water, or reagents could considerably vary, influencing the final income of the designed plant.