Low density mist collector pad

Abstract

A wire mesh mist collector pad having multiple density zones, the zones being arranged other than to provide a constantly increasing density gradient, provides a reduced pressure drop and increased capacity.

1 . A knitted wire mesh mist collector pad, comprising: at least three zones of flattened and crimped wire mesh tube, at least two of said zones comprising meshes of different densities, and the zones arranged so that the density gradient in the direction of gas flow through the pad varies from low to high to low or from high to low to high. 
   
   
       2 . The mist collector pad of  claim 1 , wherein the lowest density zones are the first and last zones taken in the direction of the gas flow. 
   
   
       3 . The mist collector pad of  claim 1 , comprising at least four zones, the zones alternating between higher and lower density meshes. 
   
   
       4 . The mist collector pad of  claim 3 , comprising five zones, the first and last zones taken in the direction of the gas flow having the lowest density meshes. 
   
   
       5 . The mist collector pad of  claim 1 , wherein at least one zone comprises wire mesh that has been crimped twice. 
   
   
       6 . A method for making a mist collector pad, comprising: providing predetermined cut lengths of first and second flattened, crimped, knitted wire mesh tubes having different densities from each other; layering one or more of said predefined cut lengths of said first tubes to define a first zone; layering one or more of said predefined cut lengths of said second tubes to define a second zone; layering one or more predefined lengths of said first tubes or of third tubes having a density different than said first and second tubes to define a third zone; and securing said first, second, and third zones in a grid suitable for installing in a process gas stream, wherein the respective densities of the meshes in the respective first, second, and third zones in the direction of the gas flow are lower, higher, and lower, or higher, lower, and higher. 
   
   
       7 . The method of  claim 6 , comprising layering to provide at least four zones with meshes having densities changing from lower to higher to lower to higher in the direction of the gas flow. 
   
   
       8 . The method of  claim 7 , comprising layering to provide at least five zones, the first and last zones each having a mesh with a density less than the densest mesh therebetween. 
   
   
       9 . The method of  claim 6 , comprising layering to provide at least six zones alternating between more and less dense meshes. 
   
   
       10 . The method of  claim 8 , comprising layering to provide an odd number of zones greater than or equal to five. 
   
   
       11 . A process vessel comprising the mist collector of  claim 1 .