Contact tray for mass and heat exchange apparatus

A contact tray for mass and heat exchange apparatus comprising:

• a planar base adapted to be rigidly secured in a vertically extending column, a plurality of apertures being formed in said base;
• and
• a plurality of valves, each of which is located in a respective one of said apertures, each of said valves comprising a member formed of sheet material having the initial configuration of a circular sector with a truncated apex, said member being defined by a body portion, a pair of peripheral side portions and an outer segment portion having an arcuate edge region extending between said peripheral side portions each of said peripheral side portions being bent towards said base along a respective radius of said member with respect to said body portion to form opposed valve side walls integral with and extending inwardly towards said base from said valve member body portion and so that the upper wall of the valve is shaped substantially as an isosceles trapezoid whose larger parallel side is directed towards the direction of outlet of gas from the valve, and said outer segment portion being bent with respect to said body portion to extend inwardly towards said base from said valve member body portion to form a limiter portion of said valve for limiting the movement thereof to its closed or lower position by way of contact of a point on the arcuate edge region thereof with said base, said body portion forming the upper wall of the valve and an upper position limiter portion for limiting the movement of the valve to its open or upper position, said upper position limiter portion constituting a plate punched from said base to form the aperture in which a respective valve is located, said plate extending upwardly at an acute angle to said base from one edge thereof which is integrally connected to said base.