# A Feasibility Study of Utilizing Nuclear Energy for an Existing MED-TVC Desalination Plant
## 3 Simulation of MED-TVC Desalination Plant
The heat flow (\(\rm Q_{i}\)) resulting from the condensation of the vapor inside the tube bundle to the sprayed seawater inside the effect shell is estimated as follows:  
\[\rm Q_{i}=V_{i}Lv_{i} \tag{5}\]  
In the simulation, the temperature of the first effect is assumed to be 70 \({}^{\circ}\)C, where the temperature is reduced gradually from the first effect until the last effect at a rate of 3 \({}^{\circ}\)C, so that the temperature of the distillate that comes out of the tenth effect is 40 \({}^{\circ}\)C. The considered seawater characteristics in the simulation are assumed to be similar to those of Red Sea conditions, as shown in Table 2.  
The flowsheet was completely built and simulated using Aspen Plus. The results obtained from Aspen Plus agree with the actual data of the MED-TVC desalination plant. Table 3 shows the overall mass and enthalpy balances of the existing MED-TVC desalination plant. Table 4 shows the simulation results of several streams of the second, sixth, and tenth effects as well as the simulation results of the TVC stream. Table 5 shows a comparison between the actual stream information of the existing MED-TVC plant and the simulation results for the desalination plant. \begin{table}
\begin{tabular}{c c} \hline Red Sea Average Temperature & 33 \({}^{\circ}\)C \\ \hline Red Sea Water Specifications & \\ \hline Chloride (\(\rm Cl^{-}\)) & 22,000 ppm \\ \hline Sodium (Na\({}^{+}\)) & 12,032 ppm \\ \hline Total hardness (CaCO\({}_{3}\)) & 8373 ppm \\ \hline Magnesium (Mg\({}^{++}\)) & 1570 ppm \\ \hline Calcium (Ca\({}^{++}\)) & 738 ppm \\ \hline Potassium (\(\rm K^{+}\)) & 287 ppm \\ \hline Total dissolved solids (TDS) & 45,000 ppm \\ \hline \end{tabular}
\end{table} 
Table 2: Approximate Red Sea water specifications. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & \multicolumn{6}{c}{**2 nd Effect**} & \multicolumn{6}{c}{**6 th Effect**} \\ \hline
**Stream** & **Seawater** & **Vapor** & **Distillate** & **Brine** & **Seawater** & **Vapor** & **Distillate** & **Brine** \\ \hline T (\({}^{\circ}\)C) & 58 & 66.67 & 64 & 66.67 & 54.2 & 53.33 & 52 & 53.33 \\ \hline P (bar) & 1.50 & 0.26 & 0.24 & 0.26 & 2.2 & 0.14 & 0.14 & 0.14 \\ \hline \(\dot{m}\) (ton/h) & 1740 & 319.75 & 334.85 & 2825.28 & 1739.96 & 403.17 & 360.10 & 8367.03 \\ \hline \multicolumn{6}{c}{**10 th Effect**} & \multicolumn{6}{c}{**Thermal Vapor Compressor (TVC)**} \\ \hline
**Stream** & **Seawater** & **Vapor** & **Distillate** & **Brine** & **Motive Steam** & **Entrained Vapor** & **Compressed Vapor** \\ \hline T (\({}^{\circ}\)C) & 40.51 & 40.5 & 40 & 40.5 & 201.40 & 53.33 & 147.17 \\ \hline P (bar) & 3.4 & 0.07 & 0.07 & 0.07 & 15.40 & 0.14 & 0.14 \\ \hline \(\dot{m}\) (ton/h) & 690.36 & 493.86 & 450.21 & 9428.25 & 238.05 & 92.73 & 330.78 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Selected streams results obtained from MED-TVC simulation flowsheet. \begin{table}
\begin{tabular}{c c c} \hline \hline  & **Input** & **Output** \\ \hline  & **Seawater** & **Brine** & **Distillate** \\ \hline Flowrate (ton/h) & 13,200.00 & 9428.25 & 3771.75 \\ \hline Volumetric flowrate (m\({}^{3}\)/h) & 13,104.07 & 9305.85 & 3794.03 \\ \hline Enthalpy flow (GW) & \(-56.34\) & \(-39.76\) & \(-16.58\) \\ \hline Temperature \({}^{\circ}\)C & 40.50 & 40.52 & 35.00 \\ \hline Pressure (bar) & 2.3 & 1.6 & 1.0 \\ \hline Mass Flows (ton/h) & & & \\ \hline H\({}_{2}\)O & 12,603.1 & 8831.342 & 3771.75 \\ \hline Na\({}^{+}\) & 149.0455 & 149.0464 & 0 \\ \hline Cl\({}^{-}\) & 305.9917 & 305.9935 & 0 \\ \hline CaCO\({}_{3}\) & 109.7203 & 109.721 & 0 \\ \hline Mg\({}^{++}\) & 19.44825 & 19.44837 & 0 \\ \hline Ca\({}^{++}\) & 9.141919 & 9.141974 & 0 \\ \hline K\({}^{+}\) & 3.555191 & 3.555212 & 0 \\ \hline Total & 13,200.00 & 9428.25 & 3771.75 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Overall mass and energy balances of the existing MED-TVC desalination plant.