Ice Preventing System and Method for a Gas Well

Abstract

An ice preventing system for a flow passage of a well or pipe line includes a fluid tank holding an ice prohibiting fluid and a pressure inducer positioned in the flow passage. The fluid tank is fluidically connected to the flow passage at an upstream location from the pressure inducer by an inlet pressure line. And the fluid tank is fluidically connected to the flow passage at a downstream location from the pressure inducer by a fluid injection line. A normally closed valve is disposed across the fluid injection line that is opened by a pressure differential across the pressure induce by ice accumulation in the flow passage, thereby allowing injection of the ice prohibiting fluid into the flow passage from the tank. Once the pressure differential lowers by removing the ice accumulation, the valve once again closes, and fluid injection stops.

What is claimed is: 
     
         1 . An ice preventing system for a well, the system comprising:
 a pressure inducer disposed across a flow passage of a well;   a tank containing a quantity of ice prohibiting fluid;   an inlet pressure line connected to said tank in fluid communication with the flow passage of the well at a position downhole of said pressure inducer;   an injector line connected to said tank in fluid communication with the flow passage of the well at a position uphole of said pressure inducer; and   a check valve disposed across said injector line and normally biased to prevent the discharge of said ice prohibiting fluid from said injector line and into the flow passage.   
     
     
         2 . The ice preventing system of  claim 1 , wherein said inlet pressure line extends through said pressure inducer. 
     
     
         3 . The ice preventing system of  claim 2 , wherein said pressure inducer is a horizontal plate having a diameter less than the diameter of the flow passage. 
     
     
         4 . The ice preventing system of  claim 1 , wherein said pressure inducer is centrally disposed within the flow passage. 
     
     
         5 . The ice preventing system of  claim 1 , wherein said ice prohibiting fluid is liquid methanol. 
     
     
         6 . A method of removing ice accumulation in a flow passage of a well, the method comprising the steps of:
 providing an ice preventing system , the ice preventing system having:   a pressure inducer disposed across a flow passage of a well;   a tank containing a quantity of ice prohibiting fluid;   an inlet pressure line connected to said tank in fluid communication with the flow passage of the well at a position downhole of said pressure inducer;   an injector line connected to said tank in fluid communication with the flow passage of the well at a position uphole of said pressure inducer; and   a check valve disposed across said injector line and normally biased closed to prevent the discharge of said ice prohibiting fluid from said injector line and into the flow passage;   injecting said ice prohibiting fluid into the flow passage when a pressure differential across said inducer is sufficient to bias said check valve open; and   ceasing injection of said ice prohibiting fluid into the flow passage when the pressure differential across said inducer is not sufficient to bias said check valve open.   
     
     
         7 . The ice preventing system of  claim 6 , wherein said inlet pressure line extends through said pressure inducer. 
     
     
         8 . The ice preventing system of  claim 7 , wherein said pressure inducer is a horizontal plate having a diameter less than the diameter of the flow passage. 
     
     
         9 . The ice preventing system of  claim 6 , wherein said pressure inducer is centrally disposed within the flow passage. 
     
     
         10 . The ice preventing system of  claim 6 , wherein said ice prohibiting fluid is liquid methanol. 
     
     
         11 . An ice preventing system for a flow passage, the system comprising:
 a pressure inducer disposed across the flow passage;   a tank containing a quantity of ice prohibiting fluid;   an inlet pressure line connected to said tank in fluid communication with the flow passage at a position upstream of said pressure inducer;   an injector line connected to said tank in fluid communication with the flow passage at a position downstream of said pressure inducer; and   a check valve disposed across said injector line and normally biased to prevent the discharge of said ice prohibiting fluid from said injector line and into the flow passage.   
     
     
         12 . The ice preventing system of  claim 11 , wherein said inlet pressure line extends through said pressure inducer. 
     
     
         13 . The ice preventing system of  claim 12 , wherein said pressure inducer is a plate having a diameter less than the diameter of the flow passage. 
     
     
         14 . The ice preventing system of  claim 11 , wherein said pressure inducer is centrally disposed within the flow passage. 
     
     
         15 . The ice preventing system of  claim 11 , wherein said ice prohibiting fluid is liquid methanol.