10 results about "Carbon isotope composition" patented technology

A semi-closed pyrolysis system, including a liquid nitrogen freezing device, a gas-liquid collector and a pyrolysis gas collecting device. The liquid nitrogen freezing device includes a collecting vessel, a liquid nitrogen storage, an air inlet pipe, an air outlet pipe and a temperature detector. The collecting vessel is arranged in the liquid nitrogen storage container, and is provided with a stainless steel cap. The stainless steel cap is provided with three holes respectively for the air inlet pipe, the air outlet pipe and the temperature detector to pass through. The air inlet pipe and the air outlet pipe are each provided with a valve. The temperature detector includes a probe and a temperature sensor electrically connected with the probe. The probe extends into the collecting vessel. A method for determining carbon isotope composition of light hydrocarbon monomers based on such system is further provided.

The invention discloses a method for determining carbon isotopes of low-concentration soluble organic carbon in a water body, and belongs to the technical field of organic carbon detection. The determination method comprises the following steps: combining a TOC analyzer and a stable isotope mass spectrometer, and converting DOC in a water body into CO2 gas by adopting the TOC analyzer; cO2 gas generated by the TOC analyzer is enriched for the first time through the cold trap T1; the CO2 gas frozen by the cold trap T1 is enriched for the second time through a cold trap T2; introducing the CO2 subjected to secondary enrichment into a stable isotope mass spectrometer, and determining the carbon isotope composition of the CO2. Aiming at a low-concentration DOC water body, the carbon isotope composition of DOC in the water body is determined on the basis of combination of a wet oxidation technology and stable isotope mass spectrometry detection, a wet oxidation method is used for increasing the volume of a water sample to generate more CO2 for stable isotope mass spectrometry determination, so that more accurate carbon isotope composition is obtained, and the method is efficient, time-saving, labor-saving and accurate.

The invention discloses an automatic analysis device and method for carbon isotope in deep sea water dissolved gas, and relates to the technical field of laser spectrum analysis, the device comprises an automatic sample introduction unit and a laser spectrum detection unit; the automatic sample injection unit is used for automatic sample injection of seawater separation sample gas and sample injection of standard gas; the laser spectrum detection unit is used for executing the functions of spectrum data acquisition, signal-to-noise ratio enhancement, data post-processing and carbon isotope composition calculation; the laser spectrum detection unit comprises three lasers, and the first laser is a methane laser corresponding to a main methane absorption spectral line; the second laser is a methane isotope laser and corresponds to 12CH4 and 13CH4 methane isotope absorption spectral lines; and the third laser is a carbon dioxide isotope laser and corresponds to carbon dioxide isotope absorption spectral lines of 12CO2 and 13CO2. The carbon isotope of methane and carbon dioxide gas dissolved in deep sea water is detected by using an automatic sample injection and automatic measurement method.

The invention belongs to the technical field of deep-time atmosphere carbon dioxide isotope composition estimation, and particularly relates to a high-resolution deep-time atmosphere carbon dioxide isotope composition estimation method and system, and the method comprises the steps: S100, reconstructing the global surface average temperature based on the atmosphere carbon dioxide concentration pCO2; s200, calculating the relative content of carbonate ions and bicarbonate radical ions in the marine carbonate system; s300, determining a fractionation coefficient; s400, determining a difference value V of carbon isotopes of the carbonatite and surrounding seawater in the carbonatite deposition process on the basis of the carbon isotope difference of the carpopods and the carbonatite; according to the method, carbonate rocks which generally exist in geological history and are continuously deposited on time are selected as a tool for atmospheric carbon dioxide isotope reconstruction, and the atmospheric carbon dioxide isotope is reconstructed through quantitative evaluation of the geological history ocean surface layer temperature, the ocean carbonate rock salt content and the fractionation effect during formation of the carbonate rocks. And the atmospheric carbon dioxide isotope composition in the deep-time geological historical evolution process can be accurately calculated.

The present invention belongs to the technical field of determination of carbon isotope composition of methane in gas, and specifically discloses an online continuous flow extraction device for methane in gas and a carbon isotope composition analysis method, the device comprises a first six-way valve, a plurality of helium inlets connected to the first six-way valve, a second six-way valve connected to the first six-way valve, a helium inlet connected to the second six-way valve, a carbon dioxide collection pipe connected to the second six-way valve, a single-opening quartz tube connected to the second six-way valve, and a stable isotope mass spectrometer connected to the second six-way valve, the method is as follows: step 1, gas sample loading; step 2, back-blowing to degas, exhaust the air in the pipes at both ends of the gas collection pipe; step 3, oxidation, purification and collection of methane in the gas; step 4, carbon dioxide sublimation injection; step 5, methane carbon isotope determination. The present invention solves the problems of excessive consumption of sample preparation gas for offline pretreatment, cumbersome operation process and low efficiency.

The invention discloses a method for detecting light hydrocarbon monomer hydrocarbon carbon isotope composition in a semi-open system thermal simulation product, and belongs to the technical field of oil gas geology. According to the method, a liquid nitrogen freezing enrichment light hydrocarbon device is added into a semi-open system thermal simulator, liquid nitrogen is kept at the position of 2 / 3 or above of a 10 ml glass collection bottle through an optimization method, the reading of a temperature detector is kept at-100 DEG C to-130 DEG C, C5-C8 light hydrocarbon collection is completed after 60 s to 90 s, and C1-C4 with the capacity larger than 300 ml is obtained through collection at the same time. The obtained two parts of hydrocarbon compounds can well meet the requirements of subsequent experiments. According to the technical scheme, the conventionally obtained solid, liquid and gas (C1-C4) products are not affected, C5-C8 light hydrocarbons enriched in the gas are also carried, scientific research on the geochemical characteristics of the hydrocarbon source rock thermal simulation products can be enriched, and double benefits are achieved.

The invention relates to the field of oil-gas exploration, and discloses a method for determining an effective gas source rock exhaust threshold by using a delta13C1-Ro relationship, and the method comprises the steps: obtaining corresponding vitrinite reflectance of an effective gas source rock stratum section at different buried depths, and drawing an evolution curve of the vitrinite reflectance with respect to the buried depths; obtaining the methane stable carbon isotope composition of the found natural gas in the research area; natural gas causes and sources are judged, and natural gas from the effective gas source rock stratum section is screened out; establishing a relationship between natural gas methane stable carbon isotope composition from the gas source rock and vitrinite reflectivity, and drawing a change curve; and determining the exhaust threshold of the effective gas source rock stratum section by utilizing the screened natural gas methane stable carbon isotope composition value in combination with the evolution curve and the change curve. According to the method, the accuracy and the pertinence of determining the exhaust threshold are improved based on actual geochemical data inversion.

The invention relates to the technical field of oil and gas geochemistry, in particular to a well site gas sample methane carbon isotope ratio distortion identification method and system. The method comprises the following steps: constructing a methane carbon isotope ratio distortion identification chart based on gas cylinder standing diffusion experiment data; judging whether the collected well site gas sample data is distorted or not based on the methane carbon isotope ratio distortion judgment plate; the collected well site gas sample data comprises methane concentration and carbon isotope ratio; when the acquired well site gas sample data is judged to be distorted, correcting the acquired well site gas sample data; and acquiring the original methane carbon isotope ratio of the well site gas sample based on the corrected well site gas sample data. According to the invention, by inputting actual test data into the chart, whether the methane carbon isotope composition of the collected gas sample is distorted or not can be qualitatively judged; the original methane carbon isotope composition at the initial stage of gas sample collection can be quantitatively recovered by calibrating parameters of the mathematical model through measured data.

The application provides an innovative method for analyzing carbon isotope composition of trace gas inclusions in mantle mineral rocks. The cavity of the ball mill and the mineral rock sample in the cavity are cleaned by a protective gas to remove possible gas impurities; the mantle mineral rock sample is placed in the micro-cavity of a three-dimensional high-energy vibration ball mill for vibration ball milling treatment. The released gas inclusions are transferred to a gas chromatography-isotope ratio mass spectrometry analysis system through a sealed rotary three-way valve for accurate carbon isotope composition analysis. The risk of non-native gas pollution can be significantly reduced through normal temperature crushing technology. Combined with ultra-trace gas extraction technology and efficient pre-concentration technology, the effective recovery and enrichment of trace gas in the gas inclusions in the mantle mineral rock are realized. By using high-sensitivity and high-precision isotope ratio measurement technology, the detection limit is improved, the background interference is effectively reduced, and the reliability of the analysis result is ensured.

Embodiments of the present application relate to the application of thermal methods to test or analyze materials, and in particular to a method for estimating the precipitation temperature of pitchblende in granite-type low-temperature hydrothermal uranium deposits, which can include the following steps: S10: collecting vein ore samples containing primary pitchblende veins in the survey area; S20: processing the vein ore samples to obtain calcite single mineral samples and fluorite single mineral samples; S30: analyzing the calcite single mineral and fluorite single mineral samples to determine the carbon isotope composition of the calcite single mineral samples and the carbon isotope composition of the fluid inclusions in the fluorite single mineral samples; S40: determining the carbon isotope equilibrium temperature according to the carbon isotope composition; S50: determining the precipitation temperature of pitchblende in granite-type low-temperature hydrothermal uranium deposits according to the carbon isotope equilibrium temperature. The method provided by the embodiments of the present application can determine the precipitation temperature of pitchblende through the carbon isotope composition of the coeval calcite and fluorite, and the determined precipitation temperature is accurate and reliable.