Patent GB-862266-A (GB)
Title: Regenerative furnace and process for utilisation thereof
IPC: F28D17/00
Filed: 1957-07-16
Abstract: <PICT:0862266/III/1> Apparatus for carrying out the thermal conversion of reactive gases, e.g. to produce carbon black, comprises a pair of regenerative masses, the axes of which are disposed in nonlinear relationship, each having gas-conducting paths spaced laterally from each other therethrough, a combustion zone positioned adjacent one end of each of said masses and communicating with said paths, and a control chamber through which gas can be fed to either mass at the end opposite said combustion zone, a plurality of burners spaced laterally from each other and linearly from the ends of said masses, being provided for projecting fuel during a heating step at laterally spaced apart intervals into said combustion zone and toward the adjacent end of one of the masses in substantially countercurrent relation to gas emerging from the paths of such mass and in a laterally distribution pattern selected to minimize, during heating, temperature variations in any plane within the other of said masses normal to the flow of gas therethrough.  The furnace 10, having a heat insulating lining 12, has two regenerative masses 13 and 14 disposed in side by side relationship separated by heat insulating wall 15, and joined at one end by a chamber or combustion space 16. Each of the masses is comprised of suitable refractory elements having the property of permitting the flow of gas therethrough and the capability of storing and releasing the heat quantities involved in the process conducted in the furnace.  Plenum chambers 21 and 22 and piping connections 23 and 24 are provided for introduction and withdrawal of gases to and from the ends of the regenerative masses opposite to the combustion space.  Chamber 16 is provided with fuel injecting means 25 and 26 which may comprise channels 27 and 28, respectively, for gaseous or liquid fuel, and two groups of injectors 27 and 28 project through end casing 29 of furnace 10, and refractory liner 30.  Fuel is preferably directed through openings 49 or 50 in mixing baffles 35 or 36, respectively.  Each of the injectors may operate at near sonic velocity so that the fuel will remain in a high velocity stream at least until it has approached openings 49 or 50 in baffle 35 or 36.  Alternatively, openings 47 and 48 in the refractory liner 31 may constitute the injection means with injectors 27 and 28 withdrawn to a point nearer end casing 29 of furnace 10.  Air for combustion passes through either mass 13 or 14 and is preheated as it approaches chamber 34 or 36 and usually enters said chambers at a much lower velocity than the fuel exiting from openings 47 and 48. As fuel in a plurality of streams approaches either chamber 34 or 36, it penetrates the air flow from such chambers and intimately mixes with the streams of preheated air.  The mixture of preheated air and fuel ignites and combustion continues as the mixture passes through chamber 16.  The hot combustion reactants and/or products are further mixed as they pass through baffle 35 or 37 prior to entry into the regenerative mass 13 or 14 respectively to be heated.  Further mixing of the combustion reactants can be obtained by providing an intermediate mixing baffle 51.  For initial ignition purposes a pilot burner may be provided in chamber 16.  The heating, cracking and quenching recurrent cycle is repeated alternately from mass 13 to mass 14.  Where an endothermic alteration reaction based upon two-part cycle operation is to be carried out, only one set of fuel injectors is required, depending upon the single flow direction chosen for the feed material being reacted, the flow of gases in the heating step being in the other and reverse direction.  Where reheating occurs by flowing hot combustion gases through mass 13, only injectors 28 are necessary whereas when reheating occurs by flowing hot combustion gases through mass 14, only injectors 27 are used. Specification 716,814 is referred to.