Method and apparatus for separating liquid from a gas stream

Abstract

An apparatus for separating liquid from a gas stream. The apparatus includes an elongated housing having a cylindrical inner surface and a gas stream inlet that is tangential to the side wall of the housing so as to cause the entering gas stream to swirl within the housing. A gas stream outlet is located at the top of the housing and a liquid outlet at the bottom. The gas stream outlet can include an elongated tubular member that extends into the housing and has an opening that is located below the housing gas stream inlet. Liquid components of the gas stream separate from the stream under the influence of centrifugal forces that are created by the swirling flow path of the stream within the housing. A liquid outlet and liquid outlet valve are provided for maintaining a minimum level of liquid within the housing so as to maintain a liquid seal within the housing. A level indicator may optionally be provided to monitor the liquid level within the housing. A power generation apparatus having two or more of the separators for separating liquid from fuel cell and fuel processor steams. Methods for manufacturing an apparatus for removing liquid from a gas stream and methods for separating liquid from a gas stream are also provided.

What is claimed is:  
     
         1 . An apparatus for separating liquid from a gas stream, the apparatus comprising: 
 an elongated housing having an inner cylindrical surface;    a gas stream inlet on a side wall of the housing, said gas stream inlet being tangential to the side wall so as to cause the gas stream to swirl within the housing;    a gas stream outlet located in an upper portion of the housing;    a liquid outlet located below the gas stream inlet, the liquid outlet having a liquid outlet valve for maintaining a minimum level of liquid within the housing.    
     
     
         2 . The apparatus of  claim 1 , further comprising a valve control system for the liquid outlet valve.  
     
     
         3 . The apparatus of  claim 2 , wherein the valve control system is a passive control system.  
     
     
         4 . The apparatus of  claim 3 , wherein the passive control system comprises a float.  
     
     
         5 . The apparatus of  claim 3 , wherein the passive control system comprises an electronic level switch, the electronic level switch comprising a float and a magnetic contactor connected to the float, the magnetic contactor movable between open and closed positions.  
     
     
         6 . The apparatus of  claim 5 , wherein the outlet valve comprises a solenoid valve connected in series with the electronic level switch.  
     
     
         7 . The apparatus of  claim 1 , wherein the gas stream outlet is aligned on a first axis and the gas stream inlet is aligned on a second axis.  
     
     
         8 . The apparatus of  claim 1 , wherein the gas stream outlet comprises an elongated tubular extension that extends from the gas stream outlet into the housing, the elongated tubular member having an opening located below the gas stream inlet.  
     
     
         9 . The apparatus of  claim 1 , further comprising a capillary material over at least a portion of an inner surface of the side wall.  
     
     
         10 . The apparatus of  claim 1 , further comprising a level indicator attached to the housing to indicate the liquid level within the housing.  
     
     
         11 . A method for manufacturing an apparatus for removing liquid from a gas stream: 
 providing an elongated housing having a cylindrical inner surface;    providing a gas stream inlet on a side wall of the housing, said gas stream inlet being tangential to the side wall;    providing a gas stream outlet on an upper portion of the housing; and    providing a liquid outlet below the gas stream inlet, the liquid outlet having a liquid outlet valve for maintaining a minimum level of liquid within the housing.    
     
     
         12 . A method for separating liquid from a gas stream, the method comprising the steps of: 
 directing a gas stream into an elongated housing;    causing the liquid within the gas stream to contact and adhere to an internal surface of the housing;    allowing a liquid-depleted gas stream to rise up through the housing to a gas stream outlet;    collecting the liquid in a lower section of the housing; and    controlling the level of liquid in the lower section of the housing so that the liquid level does not drop below a predetermined level.    
     
     
         13 . The method of  claim 12 , wherein the pre-determined liquid level is a level sufficient to provide a liquid seal in the lower section of the housing.  
     
     
         14 . The method of  claim 12 , wherein liquid adheres to the internal surface of the housing due to surface tension and capillary effect.  
     
     
         15 . The method of  claim 12 , wherein the elongated housing has a cylindrical side wall.  
     
     
         16 . The method of  claim 15 , wherein the gas stream is directed into the cylindrical housing along a path that is tangential to the cylindrical side wall of the housing.  
     
     
         17 . The method of  claim 16 , wherein liquid within the gas stream contacts and adheres to the cylindrical side wall of the housing.  
     
     
         18 . The method of  claim 12 , wherein the liquid-depleted gas stream is allowed to rise unimpeded upward through the housing.  
     
     
         19 . The method of  claim 12 , wherein the level of liquid in the lower section of the housing is passively controlled by draining liquid from the housing using a float switch.  
     
     
         20 . The method of  claim 19 , wherein the float switch actuates a solenoid valve.  
     
     
         21 . A power generating apparatus comprising: 
 a fuel processor for producing a hydrogen-rich reformate gas stream comprising water, said fuel processor connected with a combustor;    a first separator connected to the fuel processor for separating water from the hydrogen-rich reformate gas stream;    a fuel cell connected with the separator for receiving a water-depleted hydrogen-rich reformate gas stream and producing electricity and an exhaust gas stream comprising water as products of an electrochemical reaction; and    a second separator connected to the fuel cell for separating water from the fuel cell exhaust gas stream;    wherein at least one of the first and second separators in the integrated system is a separator comprising:    an elongated cylindrical housing;    a gas stream inlet on a side wall of the housing, said gas stream inlet being tangential to the side wall so as to cause the gas stream to swirl within the housing;    a gas stream outlet located in an upper portion of the cylindrical housing;    a liquid outlet located below the gas stream inlet, the liquid outlet having a liquid outlet valve for maintaining a minimum level of liquid within the housing.    
     
     
         22 . The apparatus of  claim 21 , wherein the separators are connected to a common separated water reservoir.  
     
     
         23 . The apparatus of  claim 21 , wherein the second separator is connected with the combustor for combusting a water-depleted fuel cell exhaust gas stream.