One of the most common and dangerous emissions polluting the biosphere is liquid hydrocarbon waste. It can contain more than 200 dangerous compounds. A huge pollution rate led to accumulation of more than 1 billion tons of various liquid mancaused wastes. In this connection, one of the priority tasks facing the world community is the problem of utilizing the liquid hydrocarbon wastes. A promising way of solving this problem is the fire disposal of liquid hydrocarbon wastes in flameless heat generators providing its combustion in a cryptol - the porous inert filler. Development of technical solutions for flameless heat generators is now an urgent task, requiring estimating of cryptol thermal-physical characteristics. The main aim of the research is to determine the thermal-physical characteristics of the cryptol carbon matrix and to derive the functional dependencies for analytical calculation of its preheating. The methods: cryptol heat capacity and thermal conductivity were measured on the Discovery Flash DLF-1200 thermal diffusivity analyzer in the temperature range of 298 to 573 K. Thermal-physical processes during the flat surface heating of porous filler were experimentally investigated on a specially designed experimental stand. Two variants of the stand layout - with the minimum and maximum convection intensity values - were considered. In the mathematical processing of experimental data, the effective value of the thermal diffusivity was obtained from the finite-difference analog of heat equation. As a result, the analytical dependences of thermal diffusivity on temperature were obtained. These dependences enable us to use heat equation for calculating the thermal conditions of cryptol preheating.