CN-121994712-A - Device and method for detecting content of flexible insoluble substances in oil product

Abstract

The invention relates to the technical field of petrochemical oil product detection, in particular to a device and a method for detecting the content of flexible insoluble substances in an oil product. The device comprises a solvent conveying unit, an extraction unit, a solvent recovery unit and an automatic control unit, wherein an extractor in the extraction unit is sequentially connected with an on-line refractometer and an electromagnetic valve, and the automatic controller receives the concentration of soluble substances in an extracting solution detected by the on-line refractometer and controls the flow of an injection pump, the switch interval of the electromagnetic valve and the working state of a heating component according to a comparison result of the concentration of the soluble substances in the extracting solution with a preset extraction end point concentration. The method automatically stops extraction when the concentration is lower than the concentration of the extraction end point by detecting the concentration of soluble substances in the extracting solution in real time. The invention realizes the automatic control of the extraction process, replaces the artificial naked eye with the concentration quantization index to judge the extraction end point, and obviously improves the accuracy and repeatability of the detection result.

Inventors

• SHEN HAO
• YANG JUNWEI
• JIANG SHENGLIANG
• TANG XUEMEI
• ZHANG YUEYUE
• ZHANG YANAN
• LI GANG
• MA QIANG
• LI YUNFEI

Assignees

• 中国石油大学(华东)

Dates

Publication Date

20260508

Application Date

20260410

Claims (5)

1. 1. The device for detecting the content of the flexible insoluble substances in the oil product is characterized by comprising a solvent conveying unit, an extracting unit, a solvent recovering unit and an automatic control unit; The extraction unit comprises an extractor, an online refractometer and an electromagnetic valve, wherein a liquid outlet of the extractor is sequentially connected with the online refractometer and the electromagnetic valve; The solvent recovery unit comprises an extraction bottle, a condensation pipe and a solvent recovery tank, wherein a liquid inlet of the extraction bottle is connected with the electromagnetic valve, and an air outlet of the extraction bottle is connected with the solvent recovery tank through the condensation pipe; The solvent conveying unit comprises an injection pump, a liquid inlet of the injection pump is connected with the solvent recovery tank, and a liquid outlet of the injection pump is connected with a liquid inlet of the extractor through a solvent conveying pipeline; The automatic control unit comprises an automatic controller which is respectively and electrically connected with the online refractometer, the electromagnetic valve, the injection pump and a heating component arranged on the extractor and the extraction bottle; The automatic controller can receive the concentration of the soluble matters in the extracting solution detected in real time by the on-line refractometer, and control the flow of the injection pump, the switch of the electromagnetic valve and the working state of the heating component according to the comparison result of the concentration and the preset extraction end point concentration.
2. 2. The device for detecting the content of the flexible insoluble substances in the oil product according to claim 1 is characterized in that an extractor constant temperature heating sleeve is wrapped outside the extractor, the extractor constant temperature heating sleeve is connected with the automatic controller through an extractor thermocouple, an extraction bottle heating sleeve is wrapped outside the extraction bottle, and the extraction bottle heating sleeve is connected with the automatic controller through an extraction bottle thermocouple.
3. 3. The device for detecting the content of the flexible insoluble substances in the oil product according to claim 1, wherein the sample injection end of the on-line refractometer is provided with a micro filtering and bubbling device for removing solid particles and bubbles in the extracting solution.
4. 4. A method for detecting the content of flexible insoluble matters in an oil product is characterized by comprising the steps of adding a solvent into a solvent recovery tank, placing a filter paper bag containing a test sample into an extractor, setting the constant temperature of the extractor and the concentration of an extraction end point through an automatic controller, starting an injection pump, conveying the solvent in the solvent recovery tank into the extractor to extract the sample, step S3, sequentially flowing an extracting solution into an extraction bottle after flowing through an online refractometer and an electromagnetic valve, detecting the concentration of the soluble matters in the extracting solution in real time by the online refractometer, feeding back to the automatic controller, step S4, heating the extracting solution in the extraction bottle, enabling the solvent to be vaporized into a condensing pipe, condensing and reflowing to the solvent recovery tank for recycling, step S5, dynamically adjusting the flow of the injection pump, the switching interval of the electromagnetic valve and the heating power of the extraction bottle according to the concentration of the soluble matters received in real time, and continuously controlling the extraction end point when the concentration of the soluble matters detected by the online refractometer is lower than the preset concentration of the soluble matters, and continuously stopping the operation of the extraction device, and continuously controlling the operation when the concentration of the soluble matters detected by the online refractometer is lower than the preset concentration of the preset.
5. 5. The method for detecting the content of flexible insoluble substances in an oil product according to claim 4, wherein the concentration of the extraction end point is 0.05%, and the concentration is the mass fraction of the soluble substances in the extracting solution.

Description

Device and method for detecting content of flexible insoluble substances in oil product Technical Field The invention relates to the technical field of petrochemical oil product detection, in particular to a device and a method for detecting the content of flexible insoluble substances in an oil product. Background The content of insoluble substances is an important quality index of oil products, and the accurate measurement of the insoluble substances is important for the optimization of the production process and the quality control of the product. Products such as heavy oil, asphalt and coal tar are widely used in scenes such as industrial fuel, deep processing raw materials, road pavement and the like, and the use performances such as stability, adhesiveness, combustion efficiency and the like of the products are directly reduced due to the fact that the content of insoluble substances exceeds the standard, so that the problems that asphalt pavement is prone to cracking, fuel oil is insufficient in combustion, the quality of the deep processing products is not up to the standard and the like are caused, and the use effect and the service life of the terminal products are affected. In addition, the accurate detection of the content of the flexible insoluble substances is also a necessary means for meeting the industry quality standard and normalizing the product quality, and has important significance for improving the market competitiveness of the product and promoting the normalization and refinement development of the related industries such as petroleum refining, coal chemical industry and the like. Conventional oil insoluble substances are divided into hard insoluble substances such as rigid inorganic impurities, carbon particles and the like, and flexible insoluble substances composed of colloid, asphaltene, polymer floccules, aged oil sludge and the like, wherein the flexible insoluble substances have the characteristics of soft texture, high viscosity, easy agglomeration, difficult filtration and interception, easy migration along with liquid flow and the like, and the physical property difference with the hard insoluble substances is obvious. The method is characterized in that the content of insoluble substances in the oil is detected by adopting an organic solvent extraction separation principle, organic solvents such as n-heptane, toluene and quinoline are commonly used in the industry as extraction solvents to carry out related detection, namely, a sample is wrapped in filter paper by relying on the good solubility of the solvents to oil-soluble components in the oil, the soluble components in the oil are fully dissolved and separated by heating and reflux extraction within a specified time, the residual insoluble components remain in the filter paper to be insoluble substances, and the content of the corresponding components is calculated by drying and weighing. The existing extraction separation method has good effect on qualitative and quantitative detection of conventional hard insoluble substances, but aiming at flexible flocculent and high-viscosity insoluble substances, the existing conventional extraction device and method still have difficulty in realizing accurate detection, and the main reasons are as follows: (1) The existing insoluble matter detection device is manually operated, has a simple structure, and is not provided with a standardized and refined temperature control and quantitative liquid adding component. In the detection process, the problems that the temperature of the extraction solvent is interfered by environmental heat dissipation, the reflux rate of the solvent is difficult to control and the like exist, so that the extraction efficiency is affected, and the accuracy and the repeatability of the result cannot be ensured; (2) In the existing oil insoluble matter detection method, the judgment of the extraction end point of the flexible insoluble matter lacks a unified and clear quantitative standard, the criterion is fuzzy, and whether the extraction is finished or not is judged by observing color differences by human eyes, so that the method is easily influenced by subjective factors. The decision standards of different detection personnel and different detection batches are difficult to unify, the extraction is incomplete if the detection standards are light, the detection value is lower because the flexible insoluble substances remain in the oil product, the situation of excessive extraction and excessive impurity entrainment occurs if the detection standards are heavy, the detection error is further increased, and the consistency of the detection results is poor. Even if the test is carried out according to the existing oil insoluble matter detection standard, the problems of imperfect standard rule, fuzzy end point criterion and the like are limited, the existing detection device and method still cannot realize the accurate quantitative detection of the flex