## 5 Results and Discussion
### Practical Implementation  
According to the comparative tests (Table 2) the shelf cooler-pneumoclassifier in terms of the cooling coefficient and the small fraction extraction degree exceeds pneumatic tubes devices, and units with fluidized and weighted layers, in which the specific cooling air flow rate to achieve the same cooling efficiency is 30-50% higher. The temperature of the material in the device with one shelf (if \(L_{cl}\)/\(L_{dev}\) = 0.5) decreases from 90 to 65-70 \({}^{\circ}\)C. This insignificant cooling degree is explained by the short residence time of the material moving along the inclined shelf in the gravitationally falling layer mode. At the same time, as a result of the small concentration of material particles in the workspace of the device and the close contact of the particles with the air jet, a small fraction is intensively extracted from the product. The highest dusting degree is achieved with the shelf perforation degree of \(\psi\) = 5%. If the air flow velocity in the free cross-section \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Mode; Concentration \(\beta\), m\({}^{3}\)/m\({}^{3}\)**} & \multicolumn{3}{c}{**The Residence Time of Particles with Number of Shelves, s**} \\ \cline{2-6}  & **1** & **2** & **3** & **4** & **5** \\ \hline Weighted layer; 0.3 & 7.2 & 12.4 & 17.6 & 23.0 & 28.0 \\ Weighted layer; 0.35 & 9.2 & 16.4 & 24.0 & 31.0 & 38.0 \\ Gravitationally falling layer; 0.1 & 1.3 & 2.5 & 3.8 & 5.1 & 6.4 \\ Gravitationally falling layer; 0.2 & 4.2 & 8.4 & 12.7 & 16.9 & 21.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: The residence time of solid particles in a shelf unit. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Material**} & \multicolumn{2}{c}{**Specific**} & \multicolumn{2}{c}{**Content of the Extracted**} & \multirow{2}{*}{**Cooling**} & \multirow{2}{*}{**The**} & \multirow{2}{*}{**Specific Air**} & \multirow{2}{*}{**Hydraulic**} \\  & **Productivity on** & & & & & & \\  & **the Material,** & & & & & \\  & **kg/(m\({}^{2}\)-s)** & & & & & \\ \hline Ammophos & 6 & 20 & 97.5 & 10 & 0.69 & 73 & 0.4 & 0.5–1.5 \\ Superphosphate & 6 & 40 & 100 & 26.2 & 0.6–0.65 & 50 & 0.4 & 0.5–1.5 \\  & 8 & 40 & 98 & 12.6 & 0.64–0.71 & 79 & 0.7 & 1.8–2.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Test results of a shelf cooler. of the device increases from 2.4 to 3.7 m/s, the extraction degree of the fraction of less than 1 mm in ablation is 30-60%, and the product fraction of 1-1.6 mm is not more than 1.5-2%. The cooling degree of the material on the shelf with a perforation degree of 15% and \(L_{cl}\)/\(L_{dev}\) = 0.5 increases significantly and reaches a maximum. If the specified optimal design parameters and air flow velocity in the cross-section of the device is 2.4 m/s, the \"weighted layer\" mode is implemented on the shelf, in which the particles are cooled more effectively, reaching a final temperature of 40-45 \({}^{\circ}\)C. As a result of the longitudinal mixing effect in this mode, the extraction efficiency of the small fraction is reduced to 20%. The advantage of the shelf cooler-pneumoclassifier is the possibility to separate and to cool wide fractional composition materials without clogging grids and at low hydraulic resistances not exceeding 1.5 kPa. Thanks to the pulsating unloading with the flow of the air share between the shelf perforation and the outloading gap and the intense phase contact in this space, a clear pneumatic classification is provided at high specific loads, reaching 15-20 kg/(m\({}^{2}\cdot\)s) significantly exceeding the specific loads of 0.1-1.5 kg/(m\({}^{2}\cdot\)s), at which fluidized bed coolers-separators work. In the granular mineral fertilizer technology, cooling is used to stabilize the structure of the granules [58]. Thus, drum coolers are used, which reduce the temperature of NPK fertilizer granules from 60-80 to 30 \({}^{\circ}\)C [58]. The granules are also cooled using fluidized bed coolers [59].