2-D non-stationary model of a non-isothermal steam (gas) filtration through a monospherical particle layer with internal heal generation is considered with a particular emphasis on the non-thermal steam/particles local equilibrium accounting the real non-linear properties of the media. The boundary-value problem for multiphase system gas/particles is formulated and discussed. The problem is solved numerically using the effective finite-difference fractional time-step method. It is shown that some initial thermodynamic perturbations in the system may cause localization of a steam heating (mainly due to a non-linear heal conductivity), which will lead to a temperature escalation in a specific spatial subdomains. The problem is of paramount interest for many modern industrial and natural processes.