Saturated steam quality measurement system and method

Abstract

The present invention provides for a system and method for determining saturated steam quality. The system includes a liquid inlet in communication with a pre-boiler stream of liquid creating a liquid inlet flow. An inlet chamber is in communication with the liquid inlet flow and has a inlet temperature compensated conductivity probe that is submerged in the liquid inlet flow and configured to measure the conductivity of the inlet liquid. A liquid outlet is in communication with a post-boiler outlet flow creating an outlet liquid flow. An outlet chamber is in communication with the outlet liquid flow. The outlet chamber has an outlet temperature compensated conductivity probe that is submerged in the outlet liquid flow and configured to measure the conductivity of the outlet liquid. A processor is in communication with the inlet and outlet temperature compensated conductivity probes and configured to calculate steam quality. The processor is further in communication with boiler control system wherein boiler control system is configured to adjust boiler firing rate and/or liquid flow rate based on the calculated steam quality. The method includes steps to measure the conductivity of the liquid inlet flow and outlet liquid flow and to calculate the saturated steam quality.

What is claimed: 
     
         1 . A method of determining saturated steam quality comprising the steps of:
 measuring pre-boiler conductivity of a liquid prior to entering a boiler;   measuring post-boiler conductivity of the liquid exiting the boiler; and   calculating the level of saturated steam quality of the post-boiler flow based on the pre-boiler conductivity and post-boiler conductivity measurements.   
     
     
         2 . The method of  claim 1 , further comprising the step of:
 cooling the pre-boiler liquid to an operational temperature.   
     
     
         3 . The method of  claim 2 , wherein the operational temperature is less than the saturation point. 
     
     
         4 . The method of  claim 1 , further comprising the step of:
 cooling the post-boiler liquid to an operational temperature.   
     
     
         5 . The method of  claim 4 , wherein the operational temperature is less than the saturation point. 
     
     
         6 . The method of  claim 1 , further comprising the step of:
 reducing pre-boiler liquid pressure to an operational pressure.   
     
     
         7 . The method of  claim 6 , wherein the operational pressure is near ambient. 
     
     
         8 . The method of  claim 1 , further comprising the step of:
 reducing post-boiler liquid pressure to an operational pressure.   
     
     
         9 . The method of  claim 8 , wherein the operational pressure is near ambient. 
     
     
         10 . The method of  claim 1 , further comprising the step of:
 recovering the pre-boiler liquid after the conductivity measurement.   
     
     
         11 . The method of  claim 1 , further comprising the step of:
 recovering the post-boiler liquid after the conductivity measurement.   
     
     
         12 . The method of  claim 1  wherein the measuring of conductivity is performed by utilizing a temperature compensated conductivity probe. 
     
     
         13 . The method of  claim 1  wherein the calculating of the level of saturated steam quality is performed by utilizing a processor based control system. 
     
     
         14 . The method of  claim 13  wherein the calculating of the level of saturated steam quality is continuously calculated by utilizing the processor based control system. 
     
     
         15 . The method of  claim 13  wherein the calculating of the level of saturated steam quality is calculated at a pre-established time interval by the processor based control system. 
     
     
         16 . The method of  claim 13  further comprising transmitting level of saturated steam quality to the boiler control system. 
     
     
         17 . The method of  claim 16  wherein all steps are automated and do not require human interaction. 
     
     
         18 . A system for determining saturated steam quality comprising:
 a liquid inlet in communication with a pre-boiler stream of liquid creating a liquid inlet flow;   an inlet chamber in communication with the liquid inlet flow, the inlet chamber having a inlet temperature compensated conductivity probe that is submerged in the liquid inlet flow and configured to measure the conductivity of the inlet liquid;   a liquid outlet in communication with a post-boiler outlet flow creating an outlet liquid flow;   an outlet chamber in communication with outlet liquid flow, the outlet chamber having a outlet temperature compensated conductivity probe that is submerged in the outlet liquid flow and configured to measure the conductivity of the outlet liquid; and   a processor in communication with the inlet and outlet temperature compensated conductivity probes and configured to calculate steam quality of the post-boiler outlet flow, the processor further in communication with boiler control system wherein boiler control system is configured to adjust boiler firing rate and/or liquid flow rate based on calculated steam quality of the post-boiler outlet flow.   
     
     
         19 . The system of  claim 18 , wherein the liquid outlet comprises at least one liquid separator. 
     
     
         20 . The system of  claim 19 , further comprising:
 an inlet cooler to reduce inlet liquid to operational temperature;   at least one inlet liquid valve to reduce pressure of inlet liquid to operational pressure;   an outlet cooler to reduce outlet liquid to operational temperature;   at least one outlet liquid valve to reduce pressure of outlet liquid to operational pressure;   
     
     
         21 . The system of  claim 20 , wherein the operation temperature is less than the saturation point and the operational pressure is near ambient pressure. 
     
     
         22 . The system of  claim 18  wherein the processor is in communication with multiple boilers. 
     
     
         23 . The system of  claim 18  further comprising a display device to display steam quality measurement. 
     
     
         24 . A method of determining the condition of a liquid comprising the steps of:
 measuring pre-boiler conductivity of a liquid prior to entering a boiler;   calculating the level of conductivity of the pre-boiler liquid based on the pre-boiler conductivity measurements of the liquid;   transmitting a notice to the boiler control system in the event the measured conductivity exceeds a pre-determined limit value.