US 12,480,060 B2
Development and implementation of analyzer based control system and algorithm
Jin Wang, Houston, TX (US); Nigel P. Hilton, Houston, TX (US); Glenn L. Scattergood, Sugar Land, TX (US); and Sam Ferguson, Sugar Land, TX (US)
Assigned to Ecolab USA Inc., St. Paul, MN (US)
Filed by ECOLAB USA INC., St. Paul, MN (US)
Filed on Feb. 17, 2020, as Appl. No. 16/792,610.
Application 16/792,610 is a division of application No. 15/794,215, filed on Oct. 26, 2017, granted, now 10,563,142.
Application 15/794,215 is a continuation of application No. 15/284,770, filed on Oct. 4, 2016, granted, now 9,834,732, issued on Dec. 5, 2017.
Application 15/284,770 is a continuation of application No. 13/557,761, filed on Jul. 25, 2012, granted, now 9,458,388, issued on Oct. 4, 2016.
Prior Publication US 2020/0216767 A1, Jul. 9, 2020
Int. Cl. C10G 75/02 (2006.01); G01N 17/02 (2006.01); G05B 23/02 (2006.01)
CPC C10G 75/02 (2013.01) [G05B 23/0221 (2013.01); G01N 17/02 (2013.01)] 4 Claims
 
1. A control system for controlling corrosion of a crude oil refinery process having a pH and a chloride ion concentration that change in response to system disturbances, the system comprising:
(a) a pH sensor configured to generate time-varying pH measurements of the process in response to a system disturbance, including:
(i) dynamic state pH measurements, corresponding to a condition in which the measured pH value changes while the actual pH of the process remains substantially constant; and
(ii) steady state pH measurements occurring after the dynamic state pH measurements, corresponding to a condition in which the measured pH value and the actual pH remain substantially constant;
(b) a chloride ion concentration sensor configured to generate time-varying chloride ion measurements of the process in response to a system disturbance, including:
(i) dynamic state chloride ion measurements, corresponding to a condition in which the measured chloride ion concentration changes while the actual chloride ion concentration remains substantially constant; and
(ii) steady state chloride ion measurements occurring after the dynamic state chloride ion measurements, corresponding to a condition in which the measured and actual chloride ion concentrations remain substantially constant;
(c) an analyzer in communication with the pH sensor and the chloride ion concentration sensor, the analyzer configured to:
(i) classify sensor measurements as dynamic state measurements based on characteristics of the measurements; and
(ii) apply a correction to the dynamic state pH and chloride ion measurements to generate corrected pH and chloride ion concentration values;
(d) a controller in communication with the analyzer, the controller comprising executable instructions configured to:
(i) compare the corrected pH and chloride ion concentration values to corresponding predetermined acceptable ranges;
(ii) causing one or more components of the crude oil refinery process to perform a remedial function with respect to the corrected pH value before the associated pH steady state is detected; and
(iii) causing one or more components of the crude oil refinery process to perform a remedial function with respect to the corrected chloride ion value before the associated chloride ion steady state is detected.