Abstract: The present invention relates to a method and an apparatus for the recovery and recycling of heat from hot exhaust gases, specifically from exhaust gases in metallurgical processes and from warm gases having an exiting temperature of below about 800.degree. C. According to the preferred embodiment of the present invention, warm or hot exhaust fuel gases transfer their retained heat to the lower portions of vertically positioned, capillary-type action heat transfer pipes. Cold air is then directed past the upper portion of the heat pipes, thereby transferring the heat of the heat transfer pipes to the cold air. The now heated air gains further heat, prior to introduction into the blast furnace, by passing over, previously heated refractory gratings.

Abstract: The present invention relates to a method and an apparatus for the recovery and recycling of heat from hot exhaust gases, specifically from exhaust gases in metallurgical processes and from warm gases having an exiting temperature of below about 800.degree. C. According to the preferred embodiment of the present invention, warm or hot exhaust fuel gases transfer their retained heat to the lower portions of vertically positioned, capillary-type action heat transfer pipes. Cold air is then directed past the upper portion of the heat pipes, thereby transferring the heat of the heat transfer pipes to the cold air. The now heated air gains further heat, prior to introduction into the blast furnace, by passing over, previously heated refractory gratings.

Abstract: An apparatus is provided for regulating the percentage quantities of individual gases present in the combustion air supplied for reaction processes in metallurgy. A molecular sieve absorption material is used on the intake air to absorb the inert constituents to thereby enhance the quantity of oxygen present. The apparatus utilizes several molecular sieve materials in a continuous manner such that one of the devices containing the molecular sieve material is being purged for regeneration while another device is absorbing the inert constituents, while yet another device is cooling, i.e., getting ready for the absorption operation. The countercurrent flow of heated intake air, which air is derived from the metallurgical reaction process, is used in the apparatus for regenerating the molecular sieve material.

Abstract: Methods and apparatus are provided for regulating the percentage quantities of individual gases present in the combustion air supplied for reaction processes in metallurgy. This is achieved by utilizing molecular sieve absorption processes upon the intake air in a sequential manner to remove undesirable gases attendant with the intake air and to enhance and regulate the quantity of oxygen present. The arrangement may be operated in a continuous manner through the utilization of several molecular sieve devices wherein one of such devices may be purged for regeneration and later use by countercurrent flow of heated intake air which air has been heated by the heat derived from the metallurgical reaction process in the first place.