Process for quenching the effluent gas of a furnace

Abstract

The present invention relates to a process for quenching the effluent gas of a furnace comprising: a) providing a furnace comprising a radiant zone enclosure means having a plurality of tubes disposed therein, an inlet means for introducing the process fluid into the tubes, means for exposing the external surface of the tubes to radiant heat for heating said process fluid and thereby produce an effluent gas, b) providing a quench zone having a plurality of quench tubes in which the effluent gas is passed and such as the inlet of one quench tube is connected to the outlet of one or more tubes of the radiant zone, c) recovering the effluent gas after it has been cooled in the quench tubes, wherein, at least a part of the quench tubes and advantageously all the quench tubes are tubes having means inside of it, on all the length or a part of the length, to promote turbulent flow by breaking the boundary film on the internal surface of the tube. The present invention also relates to a quench exchanger to carry out the above process.

1 . Process for quenching the effluent gas of a furnace comprising:
 a) providing a furnace comprising a radiant zone enclosure means having a plurality of tubes disposed therein, an inlet means for introducing the process fluid into the tubes, means for exposing the external surface of the tubes to radiant heat for heating said process fluid and thereby produce an effluent gas,   b) providing a quench zone having a plurality of quench tubes in which the effluent gas is passed and such as the inlet of one quench tube is connected to the outlet of one or more tubes of the radiant zone,   c) recovering the effluent gas after it has been cooled in the quench tubes, wherein, at least a part of the quench tubes are tubes having means inside of it, on all the length or a part of the length, to promote turbulent flow by breaking the boundary film on the internal surface of the tube.   
     
     
         2 . Process according to  claim 1  wherein the inlet of one quench tube is connected to the outlet of two tubes of the radiant zone. 
     
     
         3 . Process according to  claim 1  wherein all the quench tubes are tubes having means inside of it, on all the length or a part of the length, to promote turbulent flow. 
     
     
         4 . Process according to  claim 1  wherein the quench tubes have an outside diameter of about 2.5 to about 5 inches. 
     
     
         5 . Process according to  claim 1   claim 1  wherein the quench tubes have an outside diameter of about 3 inches. 
     
     
         6 . Process according to  claim 1  wherein the means inside the quench tubes are a spiral element protuberate attached to the internal surface of the tube. 
     
     
         7 . Quench exchanger close coupled to a furnace for quenching the effluent gas of the said furnace comprising:
 a plurality of quench tubes in which the effluent gas is passed and such as the inlet of one quench tube is connected to the outlet of one or more tubes of the radiant zone of the furnace,   means for recovering the effluent gas after it has been cooled in the quench tubes, wherein,   at least a part of the quench tubes are tubes having means inside of it, on all the length or a part of the length, to promote turbulent flow by breaking the boundary film on the internal surface of the tube.   
     
     
         8 . Quench exchanger according to  claim 7  wherein the inlet of one quench tube is connected to the outlet of two tubes of the radiant zone. 
     
     
         9 . Quench exchanger according to  claim 7  wherein all the quench tubes are tubes having means inside of it, on all the length or a part of the length, to promote turbulent flow. 
     
     
         10 . Quench exchanger according to  claim 7  wherein the quench tubes have an outside diameter of about 2.5 to about 5 inches. 
     
     
         11 . Quench exchanger according to  claim 10  wherein the quench tubes have an outside diameter of about 3 inches. 
     
     
         12 . Quench exchanger according to  claim 11  wherein the means inside the quench tubes are a spiral element protuberate attached to the internal surface of the tube.