Device and method for measuring carbon isotope with high cracking rate

The invention relates to the technical field of oil and gas geochemistry, and discloses a measuring device and a measuring method for carbon isotopes at high cracking rate sites. The high-cracking-rate carbon isotope measuring device comprises a first gas chromatograph, a cracking furnace and an isotope ratio mass spectrometer which are sequentially connected through a pipeline, the circulating cracking unit is used for guiding uncracked C3 components to enter the cracking furnace again. The invention relates to a method for measuring carbon isotope at a high cracking rate site. The method comprises the following steps of: cracking a C3 component flowing out of a first gas chromatograph, and feeding the cracked C3 component into a second gas chromatograph; uncracked C3 components are drained for secondary cracking; the cracking rate reaches a preset value; freezing, enriching and separating all cracked small molecular components, and vaporizing frozen components; and detecting the molecular carbon isotope. Ac