A cyclical swing adsorbent bed unit for removing contaminants from a gaseous feed stream, the adsorbent bed unit comprising: a housing forming an interior region, the housing including a body portion secured between a first head and a second head; an adsorbent bed disposed within the interior region; a plurality of first valves (516, 518) secured to the housing, wherein each of the plurality of first valves (516, 518) is configured to control fluid flow along a flow path extending from a location external to the housing through a conduit (709, 711) and to the adsorbent bed, wherein each of the plurality of first valves (516, 518) has a valve cross sectional area relative to an end of the valve (516, 518) where the stream exits or enters the valve (516, 518), the valve cross sectional area being disposed outside of an interface cross sectional area defined by the cross sectional area of an end of the adsorbent bed when viewed along an axis passing directly through the adsorbent bed along the predominant flow path, characterized in that the plurality of first valves (516, 518) are poppet valves, that the adsorbent bed is comprised of an adsorbent material supported on a non-adsorbent support, such support containing substantially parallel flow channels wherein 20 volume percent, preferably 15 volume percent or less of an open pore volume of the support, excluding the flow channels, is in pores greater than about 2nm (20 angstroms), and that the first head is configured to provide access to the adsorbent bed such that removing the adsorbent bed from the interior region does not involve removing any of the plurality of first valves (516, 518). a housing forming an interior region, the housing including a body portion secured between a first head and a second head; an adsorbent bed disposed within the interior region; a plurality of first valves (516, 518) secured to the housing, wherein each of the plurality of first valves (516, 518) is configured to control fluid flow along a flow path extending from a location external to the housing through a conduit (709, 711) and to the adsorbent bed, wherein each of the plurality of first valves (516, 518) has a valve cross sectional area relative to an end of the valve (516, 518) where the stream exits or enters the valve (516, 518), the valve cross sectional area being disposed outside of an interface cross sectional area defined by the cross sectional area of an end of the adsorbent bed when viewed along an axis passing directly through the adsorbent bed along the predominant flow path, characterized in that the plurality of first valves (516, 518) are poppet valves, that the adsorbent bed is comprised of an adsorbent material supported on a non-adsorbent support, such support containing substantially parallel flow channels wherein 20 volume percent, preferably 15 volume percent or less of an open pore volume of the support, excluding the flow channels, is in pores greater than about 2nm (20 angstroms), and that the first head is configured to provide access to the adsorbent bed such that removing the adsorbent bed from the interior region does not involve removing any of the plurality of first valves (516, 518).