An analyzer for determination of organic chloride content in crude oi

The task of developing and implementing an automated analyzer, which is a multi-module measuring system for determining the mass fraction of organochlorine compounds in crude oil, is considered. A distinctive feature of the task is ensuring high measurement sensitivity. The proposed approach is based on implementing a microcoulometric method for determining the mass fraction of organochlorine compounds after high-temperature combustion of the prepared sample in a stream of oxygen and an inert gas. The quantitative assessment of the chlorine content is carried out based on the equiatomic reaction between chlorine and silver ions, which must be pre-generated in the electrolyte. According to Faraday’s law, the amount of present chlorine is calculated by integrating the silver ion generation current in a coulometric cell. The technological parameters are controlled using proportional-integral control implemented on a programmable logic controller. The software implementation of the analyzer’s operating algorithm provides for the automated execution of all measurement stages, the registration of sensor signals, and the calculation of the mass fraction of chlorine, taking into account the volume and density of the introduced sample. The developed and implemented automated analyzer ensures that measurements are carried out in accordance with regulatory requirements and has a high degree of automation. The architecture of the hardware-software complex is developed, and algorithms for processing the measuring signal is implemented; these algorithms are based on integrating the current during the generation of silver ions, which makes it possible to provide a quantitative determination of chlorine content in the range from 1 to 60 μg/g. The proposed technical solutions ensure the reproducibility of results, ease of use, and the possibility of integrating the device into laboratory information systems.

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