Patent ID: 11940464
Assignee: ENDRESS+HAUSER OPTICAL ANALYSIS, INC.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 13:
14. A computer program product comprising a non-transitory, computer-readable medium storing instructions stored thereon that, when executed by at least one programmable processor, cause the at least one programmable processor to perform a Raman spectroscopic analysis by performing operations, comprising:
generating excitation light using a light source and transmitting the excitation light via a probe to a process sample of at least one process stream of a urea synthesis process;
detecting scattered light from the at least one process stream with a detector of a spectrometer via the probe and processing the scattered light to generate a Raman spectrum;
modeling the Raman spectrum using a chemometric model, the model including a conversion of a spectroscopy band corresponding to excitation of the carbonyl di-amide bond and of a spectroscopy band corresponding to excitation of the atomic bonds in the carboxyl form; and
determining a concentration of urea in the at least one process stream using the model of the Raman spectrum based on the modeled excitation of the carbonyl di-amide bond, wherein a concentration in the at least one process stream of carbon-containing molecules other than urea and having a carboxyl group is determined by using the model of the Raman spectrum as an equivalent concentration of carbon dioxide corresponding to the excitation of the atomic bonds in the carboxyl form,
wherein urea is synthesized from ammonia and carbon dioxide using the urea synthesis process at a pressure in the range of 100 to 300 bar and a temperature in the range of 50 to 250° C.