# Biodiesel and Biolubricant Production from Waste Cooking Oil: Transesterification Reactor Modeling
## 3 Results and Discussion
### Industrial Equipment, Reactor Design, and Economic Feasibility Study
#### 3.5.2 Main Equipment  
Also, further equipment is required for biolubricant synthesis, according to the following sequence of operations: the storage of reagents and products, a pumping system, electrical steam generation, a jacketed batch reactor, a vacuum system, a vacuum pump, and a vegetable oil purification system (see Figure 12).  
It should be noted that the equipment and budget suggested in this work is based on average real prices provided by national companies, which will not be specified because of confidentiality reasons. Thus, Table 6 provides the details of the main equipment for each step of the abovementioned sequence of operations.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameter** & **Value** \\ \hline Working hours, h\(\cdot\)y\({}^{-1}\) & 2112 \\ Collected WCO, kg\(\cdot\)y\({}^{-1}\) & 423,823 \\ Processing capacity, kg\(\cdot\)h\({}^{-1}\) & 206.03 \\ Processing capacity, kg\(\cdot\)d\({}^{-1}\) & 1648 \\ Methanol required \({}^{\star}\), kg\(\cdot\)d\({}^{-1}\) & 357.44 \\ \hline \hline \end{tabular} \({}^{\star}\) According to stoichiometric requirements.  
\end{table}
Table 5: Characteristics of the designed plant.  
The main containers used for this purpose are included in Table 7 as follows:  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Step** & **Process/Equipment** & **Details** \\ \hline WCO supply and & Shipment (tank trucks), & Steel tank for WCO and TMP storage. Bulk containers (HDPEs) were used for methanol and \\ preconditioning & filtering and storage in tanks & sodium thermoxide. \\ Pumping & Pump system & Pumps materials through the plant. \\ Steam generation & Electric steam & Provides steam to the jacketed batch reactor to control \\ generator & & the temperature at desired values. \\ First transesterification & Jacketed batch & WCO and methanol are mixed in the reactor. Once the catalyst is added, the reaction progresses. \\ First separation & Jacketed batch & Once the previous step is finished, the agitation system \\ (decantation) & reactor & is stopped to let the glycerol phase settle and be \\  & & removed from the bottom of the reactor. \\ Second transesterification & Jacketed batch & TMP and catalyst are added to FAMEs generated in the \\  & & previous transesterification, providing steam to retain \\  & reactor & the isothermal regime of the reaction. Methanol and the \\ Vacuum & Vacuum system & Viacuum is used to recover methanol, thus accelerating \\  & & the second transesterification. \\ Purification & Pumping system and & Once the reaction finishes, the resulting biolubricant is \\  & purifier & cooled down and purified (removing moisture, \\  & purifier & particles, and gas), and the resulting biolubricant is \\  & placed in a storage tank. \\ Antioxidant addition & TBHQ supply & A suitable amount of TBHQ was added to obtain the \\  & & final product. \\ \hline \hline \end{tabular}
\end{table}
Table 6: Processing steps of the designed plant.  
Figure 12: Scheme with the main components and steps carried out during biodiesel and biolubricant production from WCO.  
Concerning steam generation, specific equipment was selected for this purpose, with a working pressure range from 0.5 to 5 bar and an efficiency of 99% without carbon dioxide emissions. The boiler (840 \(\times\) 430 \(\times\) 380 mm) provides a power of 4.5 kW. Table 8 shows the main heating requirements of this process.  
Finally, the biolubricant is purified using a purifier. The quantities of biolubricant and methanol generated in the second transesterification can be calculated according to the data provided in Section 3.5.3, resulting in a volumetric flow of the biolubricant of 42.93 L-min\({}^{-1}\) when an equipment power of 44 kW and a high filtration capacity (1 \(\upmu\)m) are selected.