Method and apparatus for controlling FCC effluent with near-infrared spectroscopy

Abstract

On-line controlling of catalytic cracking processing is provided which uses near infrared (NIR) analysis to characterize FCC effluent and the resulting characterization thereof. The NIR results can be used in FCC software to control on-line unit yields and qualities.

1 . A process for controlling on line FCC effluent exhibiting asorption in the near infrared (NIR) region comprising:
 a) measuring absorbances of the effluent using an NIR spectrometer measuring absorbances at wavelengths within the range of about 780-4000 nm, and outputting an emitted signal indicative of said absorbance;   b) subjecting the NIR spectrometer signal to a mathematical treatment (e.g. derivative, smooth, baseline correction) of the emitted signal;   c) processing the emitted signal or the mathematical treatment using a defined model to determine the chemical or physical properties of the effluent and outputting a processed signal; and   d) controlling on-line in response to the processed signal, at least one parameter of an FCC process generating the effluent.   
     
     
         2 . The process of  claim 1  including the step of using NIR measuring on line to control reaction mixing sampling (RMS) on line. 
     
     
         3 . The process of  claim 2  wherein the NIR measuring of RMS provides near instantaneous prediction of FCC unit yields. 
     
     
         4 . The process of  claim 2  wherein the NIR measuring of RMS verifies FCC feed quality. 
     
     
         5 . The process of  claim 1  including the step of using NIR measuring on line of reaction effluent to control riser outlet temperature on FCC processing yields. 
     
     
         6 . The process of  claim 1  including the step of using NIR measuring of reaction effluent to control riser lift velocity. 
     
     
         7 . The process of  claim 1  including the step of using NIR measuring on line of reactor effluent to control riser lift steam rates to control FCC product yields. 
     
     
         8 . The process of  claim 1  including the step of using NIR measuring of reaction effluent to control riser lift velocity. 
     
     
         9 . The process of  claim 1  including the step of using NIR measuring on line of reactor stripper effluent to control FCC catalyst stripping. 
     
     
         10 . The process of  claim 1  including the step of using NIR measuring of reaction effluent to provide on-line modeling of FCC processing. 
     
     
         11 . The process of  claim 1  wherein said absorbances are measured at wavelengths within the range of about 780-2500 nm. 
     
     
         12 . The process of  claim 1  wherein said absorbances are measured at wavelengths within the range of 1100-2200 nm. 
     
     
         13 . The process of  claim 1  wherein said absorbance is measured in at least one wavelength and includes the steps of:
 a) periodically or continuously outputting a periodic or continuous signal indicative of the intensity of said absorbance in said wavelength, or wavelengths in said two or more bands or a combination of mathematical functions thereof,   b) mathematically converting the signal to an output signal indicative of the mathematical function; and
 controlling the FCC process on-line in response to the output signal. 
   
     
     
         14 . The process of  claim 1  wherein the step of controlling on-line allows for real time optimization processing. 
     
     
         15 . The process of  claim 1  including the steps of:
 obtaining a first data set of NIR spectroscopic data samples by subjecting the effluent to NIR spectroscopy;   generating a second data set of NIR spectroscopic data samples by processing the first data set using a second technique;   identifying a component of the effluent by performing a NIR analysis on the second data set; and   controlling the FCC process on-line in response thereto.   
     
     
         16 . The process of  claim 1  including the step of:
 mathematically converting the signal to an output signal indicative of the parameter.   
     
     
         17 . The process of  claim 7  including the steps of:
 periodically or continuously outputting a periodic or continuous signal indicative of the intensity of the NIR absorbance in the wavelength, or wavelengths in the two or more bands or a combination of mathematical functions thereof,   mathematically converting said signal to an output signal indicative of the mathematical function; and   controlling on-line in response thereto.   
     
     
         18 . The process of  claim 1  including the step of using the NIR results in FCC simulation software to control on-line unit yields and qualities. 
     
     
         19 . The process of  claim 1  which allows sampling of various locations in the reactor such as catalyst stripper vapor, reactor dilute vapor, riser vapor and reactor effluent to quantify yields and optimize the process. 
     
     
         20 . The process of  claim 1  which allows an audit of a process or mechanical change on the unit to quantify the magnitude of the change on yields, performance and economics. 
     
     
         21 . The process of  claim 1  including the step of using NIR measuring on-line of reactor dilute vapors to control riser outlet conditions and vapor quench. 
     
     
         22 . The process of  claim 3  where yields are used to tune an FCC simulation model and benchmark LP predicted yields.