## 3 Results and Discussion
### Effect of Hydrate Particle Size  
The research findings on the oxidation of the gas hydrate samples [23; 24] indicate that the size of the particle significantly affects its combustion conditions. For storage and transportation, solid gas hydrates or pressed hydrates of a large diameter should be used. For solid particles, the dissociation rate is inversely proportional to the particle radius. For pressed particles, a decrease in porosity and increase in the sphere radius \begin{table}
\begin{tabular}{c c c c c} \hline \multirow{3}{*}{\(T\), K} & **Methane-Propane Hydrate** & **Methane** & **Propane** & **Ethane** \\  & \(\tau\), s at & \(\tau\), s at & \(\tau\), s at & \(\tau\), s at \\  & \(E_{\text{a}}=190\times 10^{3}\) J/mol, & \(E_{\text{a}}=103.8\times 10^{3}\) J/mol, & \(E_{\text{a}}=61.5\times 10^{3}\) J/mol, & \(E_{\text{a}}=76\times 10^{3}\) J/mol, \\  & \(k_{0}=7.4\times 10^{8}\) s\({}^{-1}\) & \(k_{0}=5.6\times 10^{22}\) s\({}^{-1}\) & \(k_{0}=4.2\times 10^{11}\) s\({}^{-1}\) & \(k_{0}=1.04\times 10^{5}\) s\({}^{-1}\) \\ \hline
973 & \(1.8\times 10^{-2}\) & \(5.07\times 10^{-7}\) & \(1.70\times 10^{-7}\) & \(6.1\times 10^{-4}\) \\ \hline
1073 & \(6.3\times 10^{-3}\) & \(4.80\times 10^{-7}\) & \(1.05\times 10^{-7}\) & \(3.46\times 10^{-4}\) \\ \hline
1173 & \(1.52\times 10^{-3}\) & \(1.94\times 10^{-7}\) & \(6.74\times 10^{-8}\) & \(2.36\times 10^{-4}\) \\ \hline
1273 & \(5.1\times 10^{-4}\) & \(1.13\times 10^{-7}\) & \(4.43\times 10^{-8}\) & \(2.14\times 10^{-4}\) \\ \hline \end{tabular}
\end{table} 
Table 2: The ignition delay times of the methane-propane gas hydrate, methane, propane, and ethane. increases the filtration resistance and, in contrast, reduces the dissociation rate. In the combustion of large spheres, other factors are responsible for improving the efficiency of gas hydrate burnout. For pressed spheres (low porosity), almost all of the water trickles down, and the concentration of water vapors in the combustion area decreases several-fold, which significantly increases the combustion temperature. With highly porous spheres, water enters the ice frame and participates in evaporation, which leads to a higher vapor content in the combustion area and decreases the flame temperature. Pressing (reduction in the sphere porosity) increases the filtration resistance and decreases the heating rate. Lower porosity reduces the temperature conductivity of the sphere. Thus, a change in the sphere size and porosity results in the competing effect of a group of factors. Among them, the vapor content in the flame area has a decisive effect. The other factors (filtration resistance and temperature conductivity) are less significant due to a high heat flux and high dissociation rate during combustion. Therefore, it is important to consider the influence of the gas hydrate sample radius on the main characteristics of combustion start. It was established [45] that the average size of the artificial gas hydrate particles for efficient storage and usage is 0.8-1 mm. In this research, the range of 0.25-1 mm was chosen for \(R_{\text{g}}\). The ignition delay times for all of the heating schemes (Figure 3a-c) indicated that an increase in the gas hydrate particle diameter led to significantly higher ignition delay times, which is related to the dissociation rate. A greater diameter of the particle increases the filtration resistance for the gas flow in the open pores [45]. Consequently, the maximum dissociation rate is achieved for the smallest particles. The minimum concentration required for the fuel to ignite is achieved faster for a small particle than for a larger one. This is conditioned by the contribution of the decisive factors. A larger-sized hydrate particle is characterized by a great amount of water that is accumulated in the hydrate during melting, which prevents the heat transfer from the heating source to the hydrate and increases the diffusion resistance of the gaseous methane-propane.