Abstract: Disclosed is an automatic analysis method of crude oils, using spectroscopy. A near infrared spectroscopic analysis apparatus is combined with an ordinary distillation apparatus, so as to analyze the physical properties of each oil distillate as soon as it is separated from crude oils, thereby bringing about a significant improvement in analysis accuracy and in an economical aspect. It takes only two days for one person to obtain a full assay data for crude oils by taking advantage of the method. In addition to requiring a significantly reduced equipment cost, the method enables full assay data for crude oils to be obtained quickly, thereby securing more up-to-date information about crude oils and producing an economical benefit.

Abstract: A method for and an apparatus for controlling and optimizing a xylene isomer separation and isomerization process, in which near infrared light of a wavelength ranging from 1,100 nm to 2,500 nm is transmitted through samples obtained at different stages of the process from raw materials flowing in the process by use of an analyzer system using optical fibers, thereby simultaneously measuring, in an on-line manner, xylene isomers and aromatic hydrocarbons containing 6 to 9 carbon atoms from those samples. Accordingly, it is possible to monitor the entire operation state of the process within 15 minutes in an on-line manner. Conventionally, 2 to 3 days are taken for the same monitoring.