Parallel flow cryogenic liquified gas expanders

Abstract

One or more cryogenic liquefied gas expanders are configured within one or more containment vessels with parallel flow through the expanders, where cryogenic fluid enters through a common inlet and is split between a first expander and a second expander, while expanded cryogenic fluid is generated by both expanders and exits through a common outlet. Parallel flow between the liquefied gas expanders is further facilitated by a rotary control valve positioned either between vessels or between chambers within a vessel and between the two liquefied gas expanders.

What is claimed is:  
     
         1 . A parallel flow system for expanding a cryogenic fluid, comprising: 
 a cryogenic vessel having a first chamber into which the cryogenic fluid flows through a vessel inlet, a second chamber from which an expanded cryogenic fluid flows through a vessel outlet, and a divider between the first chamber and the second chamber;    a first expander positioned within the first chamber for receiving a first portion of the cryogenic fluid and producing a first portion of the expanded cryogenic fluid while a second portion of the cryogenic fluid flows through an interior of the first chamber and around an outside of the first expander;    a second expander positioned within the second chamber for receiving the second portion of the cryogenic fluid and producing a second portion of the expanded cryogenic fluid while the first portion of the expanded cryogenic fluid flows through an interior of the second chamber and around an outside of the second expander;    a first passageway within the cryogenic vessel for routing the second portion of the cryogenic fluid from the interior of the first chamber to the second chamber; and    a second passageway within the cryogenic vessel for routing the first portion of the expanded cryogenic fluid from the first chamber to the interior of the second chamber.    
     
     
         2 . The system as recited in  claim 1 , wherein the divider incorporates the first passageway and the second passageway.  
     
     
         3 . The system as recited in  claim 2 , wherein the divider includes a rotary valve.  
     
     
         4 . The system as recited in  claim 3 , wherein the rotary valve includes a rotating plate forming one or more openings therein, one or more passages for routing the first portion of the expanded cryogenic fluid from the first expander to the rotating plate, one or more passages for routing the first portion of the expanded cryogenic fluid from the rotating plate to the interior of the second chamber, one or more passages for routing the second portion of the cryogenic fluid from the first chamber to the rotating plate, one or more passages for routing the second portion of the cryogenic fluid from the rotating plate to the second expander, and a motor for turning the rotating plate, wherein a partial or complete alignment between the one or more openings, the one or more passages for routing the first portion of the expanded cryogenic fluid from the first expander to the rotating plate, and the one or more passages for routing the first portion of the expanded cryogenic fluid from the rotating plate to the interior of the second chamber creates the first passageway, and wherein a partial or complete alignment between the one or more openings, the one or more passages for routing the second portion of the cryogenic fluid from the first chamber to the rotating plate, and the one or more passages for routing the second portion of the cryogenic fluid from the rotating plate to the second expander creates the second passageway.  
     
     
         5 . The system as recited in  claim 1 , further comprising one or more valves for regulating the cryogenic fluid flow and/or the expanded cryogenic fluid flow through the cryogenic vessel, wherein the one or more valves are located outside of the cryogenic vessel.  
     
     
         6 . The system as recited in  claim 1 , wherein the first expander and the second expander are liquefied gas expanders.  
     
     
         7 . The system as recited in  claim 6 , wherein the liquefied gas expanders include one phase expanders, two phase expanders, fixed speed expanders and variable speed expanders.  
     
     
         8 . An internally controlled parallel flow system for expanding a cryogenic fluid within a cryogenic vessel, comprising: 
 the cryogenic vessel having a first chamber into which the cryogenic fluid flows through a vessel inlet and a second chamber from which an expanded cryogenic fluid flows through a vessel outlet;    a first expander positioned within the first chamber for receiving a first portion of the cryogenic fluid and producing a first portion of the expanded cryogenic fluid while a second portion of the cryogenic fluid flows through an interior of the first chamber and around an outside of the first expander;    a second expander positioned within the second chamber for receiving the second portion of the cryogenic fluid and producing a second portion of the expanded cryogenic fluid while the first portion of the expanded cryogenic fluid flows through an interior of the second chamber and around an outside of the second expander; and    a rotary valve positioned within the cryogenic vessel to create the first chamber and the second chamber and to route the second portion of the cryogenic fluid from the interior of the first chamber to the second expander and to route the first portion of the expanded cryogenic fluid from the first expander to the interior of the second chamber, whereby the first portion of the expanded cryogenic fluid and the second portion of the expanded cryogenic fluid merge at the vessel outlet to form the expanded cryogenic fluid.    
     
     
         9 . The system as recited in  claim 8 , wherein the first expander and the second expander are liquefied gas expanders.  
     
     
         10 . The system as recited in  claim 9 , wherein the liquefied gas expanders include one phase expanders, two phase expanders, fixed speed expanders and variable speed expanders.  
     
     
         11 . The system as recited in  claim 8 , wherein the cryogenic vessel has a cryogenic fluid flow capacity, and wherein the cryogenic fluid flow capacity is regulated by fully opening, partially opening or closing the rotary valve.  
     
     
         12 . The system as recited in  claim 8 , wherein the rotary valve includes a rotating plate forming one or more openings therein, one or more passages for routing the first portion of the expanded cryogenic fluid from the first expander to the rotating plate, one or more passages for routing the first portion of the expanded cryogenic fluid from the rotating plate to the interior of the second chamber, one or more passages for routing the second portion of the cryogenic fluid from the first chamber to the rotating plate, one or more passages for routing the second portion of the cryogenic fluid from the rotating plate to the second expander, and a motor for turning the rotating plate, wherein a partial or complete alignment between the one or more openings, the one or more passages for routing the first portion of the expanded cryogenic fluid from the first expander to the rotating plate, and the one or more passages for routing the first portion of the expanded cryogenic fluid from the rotating plate to the interior of the second chamber permits the expanded cryogenic fluid to flow between the first expander and the interior of the second chamber, and wherein a partial or complete alignment between the one or more openings, the one or more passages for routing the second portion of the cryogenic fluid from the first chamber to the rotating plate, and the one or more passages for routing the second portion of the cryogenic fluid from the rotating plate to the second expander permits the cryogenic fluid to flow between the interior of the first chamber and the second expander.  
     
     
         13 . The system as recited in  claim 12 , wherein the rotary valve further includes a toothed gear driven by the motor, and wherein the rotating plate includes a series of teeth around a circumference for engaging with the toothed gear to turn the rotating plate.  
     
     
         14 . The system as recited in  claim 12 , wherein the motor is a cryogenically submerged motor positioned within the cryogenic vessel.  
     
     
         15 . The system as recited in  claim 12 , wherein at least a portion of the rotating plate is formed of a Teflon-like material.  
     
     
         16 . The system as recited in  claim 12 , wherein the cryogenic vessel includes one or more seals between the first chamber and the second chamber.  
     
     
         17 . A rotary valve for use within a cryogenic vessel for routing cryogenic fluid between a first chamber and a second chamber of the cryogenic vessel, comprising: 
 a rotating plate forming one or more openings therein;    a first set of one or more passages for routing cryogenic fluid from a first portion of the first chamber to a first portion of the second chamber;    a second set of one or more passages for routing cryogenic fluid from a second portion of the first chamber to a second portion of the second chamber;    a gear for engaging the rotating plate and turning the rotating plate in a desired direction; and    a motor for driving the gear and causing the one or more openings to fully or partially align with the first set of one or more passages and/or the second set of one or more passages to control a flow of the cryogenic fluid between the first chamber and the second chamber.    
     
     
         18 . The rotary valve as recited in  claim 17 , wherein the one or more openings are fully or partially aligned with only the first set of one or more passages to route the cryogenic fluid between the first portion of the first chamber and the first portion of the second chamber, and wherein the one or more openings are not aligned with the second set of one or more passages to prevent the cryogenic fluid from being routed between the second portion of the first chamber and the second portion of the second chamber.  
     
     
         19 . The rotary valve as recited in  claim 17 , wherein the one or more openings are fully or partially aligned with only the second set of one or more passages to route the cryogenic fluid between the second portion of the first chamber and the second portion of the second chamber, and wherein the one or more openings are not aligned with the first set of one or more passages to prevent the cryogenic fluid from being routed between the first portion of the first chamber and the first portion of the second chamber.  
     
     
         20 . The rotary valve as recited in  claim 17 , wherein the one or more openings are fully or partially aligned with the first set of one or more passages to route the cryogenic fluid between the first portion of the first chamber and the first portion of the second chamber, and wherein the one or more openings are fully or partially aligned with the second set of one or more passages to route the cryogenic fluid from between the second portion of the first chamber and the second portion of the second chamber.  
     
     
         21 . The rotary valve as recited in  claim 17 , wherein the gear includes a plurality of teeth around a circumference for engaging the rotating plate and wherein the rotating plate includes a series of teeth around a circumference for engaging the plurality of teeth of the gear.  
     
     
         22 . The rotary valve as recited in  claim 17 , wherein the motor is a cryogenically submerged motor positioned within the cryogenic vessel.  
     
     
         23 . The rotary valve as recited in  claim 17 , wherein at least a portion of the rotating plate is formed of a Teflon-like material.  
     
     
         24 . The rotary valve as recited in  claim 17 , wherein the rotary valve is positioned between the first chamber and the second chamber and is surrounded by one or more seals between the first chamber and the second chamber.  
     
     
         25 . A parallel flow system for expanding a cryogenic fluid, comprising: 
 a first cryogenic vessel into which the cryogenic fluid flows through a vessel inlet including a first expander for receiving a first portion of the cryogenic fluid and producing a first portion of the expanded cryogenic fluid while a second portion of the cryogenic fluid flows through an interior of the first cryogenic vessel and around an outside of the first expander;    a second cryogenic vessel from which an expanded cryogenic fluid flows through a vessel outlet including a second expander for receiving the second portion of the cryogenic fluid and producing a second portion of the expanded cryogenic fluid while the first portion of the expanded cryogenic fluid flows through an interior of the second cryogenic vessel and around an outside of the second expander;    a first passageway between the first cryogenic vessel and the second cryogenic vessel for routing the second portion of the cryogenic fluid from the interior of the first cryogenic vessel to the second expander; and    a second passageway between the first cryogenic vessel and the second cryogenic vessel for routing the first portion of the expanded cryogenic fluid from the first expander to the interior of the second cryogenic vessel.    
     
     
         26 . The system as recited in  claim 25 , further comprising a rotary valve that incorporates the first passageway and the second passageway.  
     
     
         27 . The system as recited in  claim 26 , wherein the rotary valve includes a rotating plate forming one or more openings therein, one or more passages for routing the first portion of the expanded cryogenic fluid from the first expander to the rotating plate, one or more passages for routing the first portion of the expanded cryogenic fluid from the rotating plate to the interior of the second cryogenic vessel, one or more passages for routing the second portion of the cryogenic fluid from the first cryogenic vessel to the rotating plate, one or more passages for routing the second portion of the cryogenic fluid from the rotating plate to the second expander, and a motor for turning the rotating plate, wherein a partial or complete alignment between the one or more openings, the one or more passages for routing the first portion of the expanded cryogenic fluid from the first expander to the rotating plate, and the one or more passages for routing the first portion of the expanded cryogenic fluid from the rotating plate to the interior of the second cryogenic vessel creates the first passageway, and wherein a partial or complete alignment between the one or more openings, the one or more passages for routing the second portion of the cryogenic fluid from the first cryogenic vessel to the rotating plate, and the one or more passages for routing the second portion of the cryogenic fluid from the rotating plate to the second expander creates the second passageway.  
     
     
         28 . The system as recited in  claim 25 , further comprising one or more valves for regulating the cryogenic fluid flow and/or the expanded cryogenic fluid flow from the first cryogenic vessel to the second cryogenic vessel, wherein the one or more valves are located outside of either the first cryogenic vessel or the second cryogenic vessel.  
     
     
         29 . The system as recited in  claim 25 , wherein the first expander and the second expander are liquefied gas expanders.  
     
     
         30 . The system as recited in  claim 29 , wherein the liquefied gas expanders include one phase expanders, two phase expanders, fixed speed expanders and variable speed expanders.