Abstract:
A stabilizing assembly for a poppet valve in a regenerative thermal oxidizer comprises a plurality of rigid bars, spanning a poppet valve gap, arranged circumferentially around a chamber outlet.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims priority under 35 U.S.C. § 119 and applicable foreign and international law and incorporates in its entirety the following U.S. Provisional Patent Application Ser. No. 60/490,348 filed Jul. 24, 2003. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The invention relates to regenerative thermal oxidizers (RTO) for converting solvent laden gases to CO 2  and H 20 .  
       BACKGROUND  
       [0003]     RTOs typically have multiple chambers separated by one or more poppet valves. A poppet valve controls the flow of gas in and out of the chambers. Examples of RTOs are shown in U.S. Pat. No. 6,039,927 and U.S. Pat. No. 6,129,139, each of which is hereby incorporated by reference in its entirety.  
         [0004]     Proper and efficient operation of the RTO depends on the ability of a poppet valve to maintain a tight seal around a chamber opening. However, with repeated forceful opening and closing, the valves tend to deteriorate over time. The high force with which the valves close, or “slam” shut, typically tends to cause premature wear of valve seats. Lack of constant air pressure in the RTOs, and temperature variability of many hydraulic fluids, and ambient variances all cause inconsistent strains and stresses on the poppet valve. 
     
    
     THE DRAWINGS  
       [0005]      FIG. 1  is a perspective view of an RTO.  
         [0006]      FIG. 2  is a partial perspective view of a stabilized poppet valve in an RTO.  
     
    
     DESCRIPTION  
       [0007]      FIG. 1  shows RTO unit  20 . Oxidizer  20  has separate chambers  22  and  24  separated by a poppet valve (not visible in  FIG. 1 ). Door  26  is provided on the side of RTO  20 .  FIG. 2  shows the view seen when door  26  is open.  
         [0008]     In  FIG. 2 , poppet valve  30  includes shaft  32  which is driven left and right (axially) by pneumatic cylinder  33  ( FIG. 1 ). When shaft  32  moves left, poppet blade  34  also moves left opening chamber  22 , allowing gas to flow in and/or out.  
         [0009]     The apparatus shown in  FIG. 2  employs stabilizing bars  38  across gap  36 . A significant problem with prior poppet valves in RTOs is that the seal around poppet blade  34  becomes flawed or degraded, especially after extended use. The quality of the seal around poppet blade  34  is important for oxidizer performance. Stabilizing bars  38  rigidify the relative positions of structures on opposite sides of the poppet valve resulting in superior poppet valve performance over time.  
         [0010]     In the example shown in  FIG. 2 , bars  38  rigidly connect frame components around the chamber opening. Specifically, frame component  50  is a rigid structural annular component circumscribing the opening to the chamber. As shown, eight stabilizing bars are used to support the poppet valve. However, other similar structures, or numbers of bars may also be used, provided the gap space remains relatively open while the gap space and poppet valve mechanics are substantially stabilized.  
         [0011]     The disclosure set forth above may encompass multiple distinct inventions with independent utility. Although each of these inventions has been disclosed in its preferred form(s), the specific embodiments thereof as disclosed and illustrated herein are not to be considered in a limiting sense, because numerous variations are possible. The subject matter of the inventions includes all novel and nonobvious combinations and subcombinations of the various elements, features, functions, and/or properties disclosed herein. Inventions embodied in other combinations and subcombinations of features, functions, elements, and/or properties may be claimed in applications claiming priority from this or a related application. Such claims, whether directed to a different invention or to the same invention, and whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the inventions of the present disclosure.