Abstract: A fiber bed separator and method are provided for separating aerosols of 3 microns and less from gases. Two fiber beds in intimate contact with one another are used. The first fiber bed, in the direction of gas flow is of fibers of at least about 5 microns mean diameter packed to a bed voidage of from about 85 to 98%, the fiber diameter and bed voidage being selected such that at design bed velocity and aerosol loading the first bed is not flooded and the residual saturation of said first fiber bed against gas drag on the liquid collected is less than the residual saturation of said bed against gravity drainage of the liquid. The second fiber bed is packed to a bed voidage of from about 85 to 99% with fibers of equal or greater mean diameter than those in the first fiber bed such that the residual saturation of said second fiber bed against gas drag is greater than the residual saturation of the bed against gravity drainage.

Abstract: This invention provides vertically disposed fiber bed elements and separators containing the same wherein "bubble re-entrainment" of a collected liquid phase in a gas stream flowing through the fiber bed is substantially eliminated or reduced. "Bubble re-entrainment" refers to that re-entrainment of liquid which occurs at the bottom of the fiber bed where the cumulative drainage of the liquid is at its maximum. This is accomplished by providing at the bottom of the fiber bed a vertically disposed gas flow baffle means such as, e.g., a baffle plate, such that some portion of the fiber bed is disposed downstream of the baffle means and shielded by the lee side of said baffle means from the moving gas stream, said shielding being effective throughout the shielded portion of the fiber bed to reduce the bed velocity of any gas flowing therethrough to below a bubble re-entraining velocity.