a gas consumer a heating system must be equipped with several periodical preheaters the pressure in liquid bath can be readily controlled and maintained at the level required by a gas consumer pressure in a heat consumer can be different from the pressure in a heat source for example the pressure in a furnace flue which is a source might be different from the pressure in a turbine inlet in this case the pressure in the vessel must be sustained at two different levels during heat supply to the melt and heat extraction from the melt the pressure in the vessels can be maintained at the level of 1 20 atm this ensures the optimal size of an emulsion and consequently the optimal size of the vessels the heated gas can be separated from the means of an enclosure immersed into the melt the pressure inside and outside of the enclosures are approximately equal to one another this enables us to use ceramics refractory fabrics and other nonexpensive materials for gas heating to high temperature at high pressure the melt 6 can be formed from nonexpensive readily available material having melting point lower than the temperature of gas preheating for example the molten pig iron or molten steelmaking slag can be used for gas preheating up to temperature 1300 u00b0 1600 u00b0 c these melts also can be used for extracting chemical energy of coal or wastes.