Process pumps and related methods of treating a process line

Abstract

A method of treating a fluid within a process line includes flowing a treatment chemical and a first volume of the fluid into an injection chamber of a process pump, exerting an upward force on a lower cylinder of a piston of the process pump with a mixture of the treatment chemical and the first volume of the fluid within the injection chamber, exerting a downward force on an upper cylinder of the piston with a second volume of the fluid, and transmitting the downward force to the lower cylinder of the piston to force the mixture out of the injection chamber and into the process line.

What is claimed is: 
     
         1 . A fluid processing system comprising a process pump, the process pump comprising:
 a housing comprising an upper chamber wall and a lower chamber wall; and   a piston that is movable within the housing, the piston comprising:
 a shaft, 
 a lower cylinder fixed to a lower end of the shaft and disposed within the lower chamber wall, and 
 an upper cylinder slidably coupled to an upper end of the shaft and disposed within the upper chamber wall. 
   
     
     
         2 . The fluid processing system of  claim 1 , wherein the process pump further comprises a positioning spring that is attached to the upper end of the shaft and to an upper surface of the upper cylinder. 
     
     
         3 . The fluid processing system of  claim 2 , wherein the positioning spring is biased to a collapsed configuration and is configured to lengthen to an extended configuration in response to a downward force directed on the upper cylinder. 
     
     
         4 . The fluid processing system of  claim 1 , wherein the upper cylinder and the lower chamber wall together form an upper pressure transmission chamber, and wherein the lower chamber wall and the lower cylinder together form a lower pressure transmission chamber. 
     
     
         5 . The fluid processing system of  claim 4 , wherein the process pump further comprises a conduit that extends between the upper and lower pressure transmission chambers. 
     
     
         6 . The fluid processing system of  claim 4 , wherein the upper and lower pressure transmission chambers contain a pressure transmission fluid. 
     
     
         7 . The fluid processing system of  claim 1 , further comprising:
 a chemical tank;   a process line containing a fluid to be treated by the process pump; and   a fluid circuit by which the chemical tank fluidly communicates with the process pump and by which the process pump fluidly communicates with the process line.   
     
     
         8 . The fluid processing system of  claim 7 , further comprising a plurality of automated valves positioned across the fluid circuit. 
     
     
         9 . The fluid processing system of  claim 7 , wherein the process pump is configured to pump a dose of a treatment chemical from the chemical tank through the fluid circuit and into the process line. 
     
     
         10 . A process pump comprising:
 a housing comprising an upper chamber wall and a lower chamber wall; and   a piston that is movable within the housing, the piston comprising:
 a shaft, 
 a lower cylinder fixed to a lower end of the shaft and disposed within the lower chamber wall, and 
 an upper cylinder slidably coupled to an upper end of the shaft and disposed within the upper chamber wall.