## 4 Calculating the Fuel Efficiency Indicator Using the WSM and the WPM
The choice of the temperature range was due to both the capabilities of the experimental equipment used in the experiments (heating not higher than 1000 \({}^{\circ}\)C) and the promise for practical applications. In particular, the combustion of heterogeneous components in the composition of fuel suspensions can be implemented in the specified temperature range using fluidized bed technologies [33]. Fluidized-bed combustors can be adapted to a wide range of components, including high ash components. Furthermore, relatively low temperatures (700-900 \({}^{\circ}\)C) create conditions for reducing the emission of harmful oxides [34]. A set of established parameters (absolute values) from the energy and environmental categories, as well as the fuel cost, are presented in Tables 7 and 8. Tables 9 and 10 show a set of normalized criteria for five fuel types at three heating temperatures for different countries. \(C\), SO\({}_{\times}\), NO\({}_{\times}\), \(\tau_{d1}\), \(\tau_{d2}\), \(T_{g}^{min}\) and \(A^{d}\) were normalized relative to the smallest typical value of the five fuels at a certain temperature (in case this parameter was dependent on temperature). \(Q_{a}{}^{s}\) was normalized relative to the greatest value. The data in Table 9 were obtained using Table 7 and some additional calculations and estimates. Below are comments and necessary explanations of some particular criteria. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline \(T_{g}\) (\({}^{\circ}\)C) & **Fuel** & **SO\({}_{\times}\) (ppm)** & **NO\({}_{\times}\) (ppm)** & \(\tau_{d1}\) (s)** & \(\tau_{d2}\) (s) & \(\tau_{b}\) (s) & \(Q^{a}{}_{s}\) (MJ/kg) & \(T_{g}^{min}\) (\({}^{\circ}\)C) & \(A^{d}\) (\%) \\ \hline \multirow{4}{*}{700} & 1 & 15.00 & 50.00 & 7.85 & 11.70 & 32.76 & 13.66 & 475.00 & 19.67 \\  & 2 & 12.00 & 100.00 & 8.95 & 10.13 & 25.30 & 16.37 & 400.00 & 8.06 \\  & 3 & 15.00 & 141.00 & 1.60 & 3.60 & 6.64 & 12.21 & 550.00 & 5.86 \\  & 4 & 48.00 & 60.00 & 2.95 & 7.94 & 21.90 & 13.09 & 430.00 & 17.71 \\  & 5 & 50.00 & 50.00 & 3.90 & 5.95 & 12.14 & 25.79 & 350.00 & 13.90 \\ \hline \multirow{4}{*}{800} & 1 & 25.00 & 85.00 & 6.97 & 7.50 & 26.80 & 13.66 & 475.00 & 19.67 \\  & 2 & 25.00 & 150.00 & 5.77 & 8.70 & 22.70 & 16.37 & 400.00 & 8.06 \\  & 3 & 25.00 & 157.00 & 1.25 & 3.25 & 4.85 & 12.21 & 550.00 & 5.86 \\  & 4 & 50.00 & 120.00 & 2.76 & 4.40 & 23.80 & 13.09 & 430.00 & 17.71 \\  & 5 & 200.00 & 200.00 & 2.09 & 3.79 & 13.96 & 25.79 & 350.00 & 13.90 \\ \hline \multirow{4}{*}{900} & 1 & 60.00 & 140.00 & 5.38 & 4.50 & 64.04 & 13.66 & 475.00 & 19.67 \\  & 2 & 45.00 & 250.00 & 5.15 & 6.47 & 15.10 & 16.37 & 400.00 & 8.06 \\ \cline{1-1}  & 3 & 63.00 & 180.00 & 1.25 & 1.75 & 3.15 & 12.21 & 550.00 & 5.86 \\ \cline{1-1}  & 4 & 53.00 & 175.00 & 2.50 & 3.36 & 20.30 & 13.09 & 430.00 & 17.71 \\ \cline{1-1}  & 5 & 250.00 & 275.00 & 0.75 & 1.45 & 14.68 & 25.79 & 350.00 & 13.90 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Absolute values of parameters characterizing the fuel ignition and combustion [35; 36]. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Number** & **Fuel** & **Russia** & **China** & **Japan** \\ \hline
1 & 100\% filter cake (wet) & 0.005 & 0.005 & 0.005 \\
2 & 55\% coal, 45\% water & 0.0275 & 0.0396 & 0.055 \\
3 & 40\% filter cake (dry), 50\% water, 10\% & 0.0185 & 0.0185 \\  & waste turbine oil & 0.0072 & 0.0072 & 0.0072 \\
5 & 100\% coal & 0.050 & 0.072 & 0.100 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Estimation of the comparative fuel cost for different countries (\(\xi\)/kg). \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Fuel No.