Application Methods Development In Petrochecmial Industry By Using Chemiluminence Detector With Gas Chromatograph System

The research work in this thesis was to understand the technical issue for chemluminence detector, so as to improve the high efficiency, accuracy and reliable sulfur detection solutions. Based on gas chromatography theory, as well as combined with the sulfur chemiluminence detector characteristics, a series of research work was developed. Sulfur selective detector configured with gas chromatography system has been widely used in all aspects of industry as petrochemical industry, environment industry and fine chemicals industry. With more stringent regulation requests and quanlity control process needs, there will be more and more potential developments for trace level sulfur detection. During the current sulfur detection developing in industry, kinds of technical issues always confuses chromatogram analysers. A major problem is the sensitivity decreasing, which is caused by the pollutants condensation on detector, results in the poor repeatability problem and unreliable data. By study the pneumatic system of dual-plasma sulfur chemilunesence detector, at meanwhile, study with the structural of chemiluminuce detector, an optimized method for sulfur detection was established. In addition, this work verified the decoking process could solve the current technical problem, and also described a reliable method to improve the test result.. This work firstly disclosed the detector sensitivity changing trend along with its flow condition, and then it was successfully applied to application method aiming to show the ability of solving engineering work. The research work in this thesis was divided into four chapters, main contents and the results were summarized as follows:In Chapter 1, the research backgroud and purpose of this research were introduced. With fast developing industry, especially to meet the international requirements for petrochemical industry process control and environment protection control, sulfur detection has showed extremely important role. This work discussed a sulfur chemiluminescence detector configured with gas chromatography was able to provide high sensitivity and high selectivity in determination of tracel sulfur in petroleum products, raw materials and final produts. It also summarized the unique advances of chemiluminescence detector.In Chapter 2, the technical characteristics and principles of dual plasma sulfur chemiluminescence detector (DPSCD) were described. More important, the optimized test methods and conditions were established. Due to the unique advantages:as linear equimolar response, effectively burning sample matrix so as disminishing the interference to sulfur detection; SCD has become an ideal test tool in petrochemical industry application. In the past time of method developing and research, it was ignored that studying the relationship between gas flow and detector sensitivity. To find the optimal detection method and to improve the reliability, it was critical to study the DPSCD sensitivity pattern by changing with different gas flow rate in burner. By the results of series experiments, we found the different hydrogen and air flow rate could directly impact the SCD sensitivity and could bring very different performance. This part of work provided an effective way to accurately detect different concentrations of sulfide which demonstrating the good linear correlation and it also showed satisfactory sensitivity.In Chapter 3, decoking solution was developed, so as to improve the unstable performance of volatile sulfur detection. This part of work researched the sensitivity characteristics by comparing with the two status as pre-decoking and post-decoking. It is helpful to understand the SCD performance changing pattern. This decoking method was simple and easy to carry out, which delivered a reliable and effective tool in petrochemical sample analyzing.In Chapter 4, we applied the optimized method into petrochemical samples application, such as sulfur detection in natural gas and thiophene in benzene. It is important to determine the sulfur impurities, because sulfur compounds will not only contaminate raw materials but also bring troubles in petrochemical process control. Due to the different property of sulfur compounds, it is always chanllenge to accurately determination those trace level compounds. This part of work showed high sensitivity and reliable performance by using the optimized method, and it also demonstrated the excellent result.As above, this paper focused on developing a reliable and high sensitivity method to solve current sulfide detection problems; also, it set up an optimized test condition for dual plasma sulfur chemiluminence detector operation; meanwhile, it improved and solved the unstable performance by conducting the decoking solution. These works were significantly important to improve reliability of sulfur detection in petroleum chemistry.It also demonstrated the extensive application space of sulfur chemiluminence detector in future application.