RU154434U1 - SYSTEM FOR ANALYSIS OF COMPOSITIONS OF GAS AND / OR LIQUID TECHNOLOGICAL FLOWS OF CHEMICAL PRODUCTION - Google Patents

Abstract

A system for analyzing the composition of technological streams of chemical industries, including an optical cell with optical elements connected to an optical analyzer, consisting of a housing with an internal chamber with an input and output of the investigated process flow, a pump, characterized in that it contains: - a device for measuring and regulating temperature of the optical cell connected to the optical cell; - mixing device connected to the pump; - container for storing the analyzed sample connected to the pump; - analyzer connected to the container for storing the analyzed sample; - storage container; - additional pump connected to the mixing device and storage tank, while the optical cell additionally has a branch for sampling.

Description

This utility model relates to devices for analyzing the composition of gas and / or liquid process streams of chemical plants directly “in the stream”.

In chemical production, several analyzes are usually performed to determine several characteristics of a single sample of a process stream using various types of equipment and appropriate calibration models.

Analysis by spectroscopic methods "in the stream" allows you to obtain information with almost no delay in time, since the time of registration of the spectrum is units of seconds, but does not directly give the concentrations of the components and the associated characteristics and requires additional calibration (building a calibration model). For the correct calibration (construction of a calibration model) of analytical instruments, it is necessary to determine the correspondence between the characteristic (in particular, composition) of the sample and the directly measured quantity (for example, the composition of the flow - spectrum). Production flows often have a complex multicomponent composition, which, moreover, quickly changes due to the reactions occurring in it, which makes calibration difficult, since the selected sample of the production flow changes its composition during transportation to the analytical device used to create the calibration model.

Conventional optical cuvettes cannot provide sampling while obtaining calibration data, such as temperature, spectrum and composition data, which are necessary for preparing calibration models.

In addition, the temperature difference between the test sample taken from the flow and the calibration model can lead to significant errors in the analysis. Any deviation of the measured temperature of the test sample with respect to the actual temperature of the sample "in the stream" leads to an additional error in creating the calibration model. Currently used devices for analyzing the composition of technological streams of chemical plants directly "in the stream" are not configured to work with such temperature gradients.

When measuring optical density at a specific sample temperature, the measuring cell is placed in a thermostat. If a chemical reaction occurs in the analyzed medium with the release of heat, its removal is also necessary. Such cuvettes are described in US patent No. 5296195 [published March 22, 1994] and No. 5162236 [published November 10, 1992]. These measuring devices do not have high strength, therefore, are not applicable under conditions of high pressures and significant mechanical loads that occur when used in a production environment.

In the process, there are additional requirements for measuring devices due to high mechanical loads at high pressure and high speed of production flows, as well as the destructive action of the medium. Most measuring devices are used to solve just such technical problems. To reduce the mechanical stresses on the cuvette glass, RF patent No. 80240 [published on January 27, 2009] provides special channels for the input and output of the analyzed fluid, located at an angle to the axial hole for the passage of the light beam. In the patent of the Russian Federation No. 2263303 [published on 10.27.2005] a measuring cell is described, which is firmly fixed in the housing of the original design. The fluid inlet and outlet channels are also angled. Rugged housing can be made of neutral plastic, which increases the service life when in contact with destructive flows. In US patent No. 6297505 [published 02.10.2001] describes a measuring cell for optical measurements under high pressure, the windows of which are made of especially durable material.

All flow cells described in these patents are intended solely for optical measurements and do not provide for the possibility of simultaneously recording the spectrum and sampling the analyzed medium, which is necessary for an exact match between the spectrum and the analysis carried out by an independent method.

In the present description, a system is proposed for optical analysis of the compositions of gas and / or liquid technological streams of chemical plants, the use of which eliminates the above drawback, which allows spectral analysis "in the stream" and in parallel to analyze this sample by an independent method with a minimum time difference.

A system is proposed for analyzing the composition of technological flows of chemical industries, including an optical cuvette with optical elements connected to an optical analyzer, consisting of a housing with an internal chamber having an input and output for the process stream under study, and a pump.

The system contains:

- a device for measuring and controlling the temperature of the optical cuvette connected to the optical cuvette;

- a mixing device connected to the pump;

- a container for storing the analyzed sample, connected to the pump;

- an analyzer connected to a container for storing the analyzed sample;

- storage tank;

- an additional pump connected to the mixing device and the storage tank,

- The optical cuvette additionally has a tap for sampling.

The analysis system includes an optical cuvette that has an internal fluid chamber defined by the internal surface of the body. An optical cuvette can be configured as a near infrared spectrum analysis system, however, other configurations and analysis spectra can be used.

The inner fluid chamber may be of any shape and size to measure various characteristics of fluids.

The analysis system includes an optical element tuned to direct electromagnetic radiation through a portion of the fluid passing through the internal fluid chamber. The optical element may contain optical fiber, or one or more, or optical fiber and a collimator.

The analysis system includes a positive displacement pump or piston or syringe type pumps.

The pump can be connected to a sampling outlet and a container for storing the analyzed sample through a valve that controls the input and output of the sample to the pump.

An additional pump can be connected to a mixing device and a container for storing reagent through a valve that controls the entrance and exit of the sample from the tank for storing reagent to the pump.

The analysis system includes a device for measuring and controlling the temperature of the optical cell, which consists of a temperature sensor that measures the temperature in the internal liquid chamber, or a temperature controller that monitors the temperature in the optical cell, or a sensor and controller. The temperature of the optical cell is set to the desired temperature range or temperature point. As a temperature controller, a heater, cooler, heat exchanger, etc. can be used. Also, the temperature can be controlled by a control algorithm executed through a computer to control the process.

The electromagnetic radiation passing through the liquid of the internal liquid chamber of the analysis system has an optical path length of from about 0.1 mm to about 100 mm.

The analysis system may be in fluid interaction with an oxidizing element, a concentrator, a reactor in a chemical processing plant, a container in a chemical processing plant, a container in a food processing plant, a medical sample tank, or a combination thereof.

The analysis system may be in liquid interaction with the cumene oxidation unit, the cumene hydroperoxide concentration unit (CCP), the CCP decomposition unit, the phenol purification unit, the acetone purification unit, the α-methyl styrene processing unit (AMC), the purification, hydrogenation, and para-cumylphenol production stages or a purification unit of paracumylphenol, or a combination of the above.

The analysis system may include an analyzer that analyzes at least a portion of the contents of the container for the sample to be analyzed. The analyzer can perform spectral and chemical analysis, as well as determine the physical characteristics of the analyzed sample.

Separate (independent) elements of the system through which liquid or gaseous substances pass are interconnected by technological lines (capillaries, tubes, pipelines). Technological lines can be short in order to minimize the time delay of substances passing through them.

As a mixing device, a static mixer can be used, using which there is uniform, reproducible and reliable mixing of the reagent and the sample.

The storage container may contain a solvent and / or a reagent that terminates the reaction.

In FIG. 1 shows a diagram of a system for analysis 100.

The analysis system 100 includes:

- an optical cuvette 102, which has an internal chamber 104, a housing 106, a process input 108, a process output 110;

- temperature sensor 134;

- temperature controller 136;

- an optical element 112, consisting of an optical fiber 114 connected to a collimator 116 for directing electromagnetic radiation through an internal liquid chamber 104, a return optical fiber 118 connected to a return collimator 120;

- tap for sampling 122;

- syringe pump 126;

- storage capacity 130;

- syringe pump 124;

- mixing device 132;

- capacity for storage of the analyzed sample 128;

- analyzer 138.

Example 1

The system for analysis 100 is as follows.

For analysis, part of the process stream (sample) is passed through the inner chamber 104. The sample enters the inner chamber 104 at the process input 108 and returns to the process stream in an unchanged form at the process output 110.

The sample is analyzed by absorption spectroscopy using an optical element 112 integrated in the chamber 104. In this case, the electromagnetic radiation comes from the source fiber 114 through the collimator 116 and passes through the analyzed sample. Part of the electromagnetic radiation is returned to the optical analyzer through the return optical fiber 118 and return collimator 120. The resulting spectrum is stored and analyzed by software.

At the same time, a portion of the sample is taken from the optical cuvette by a pump 124 to the sampling unit 122, which enters the mixing device 132, which also receives the reaction-terminating reagent and solvent from the storage tank 130.

Substances from storage tank 130 are supplied to device 132 using pump 126. Pump 126 is connected by a tube to storage tank 130 and is equipped with a three-way valve through which it is filled with reagent and solvent from tank 130.

Once the pump 126 is filled with the required amount of reagent and solvent, the three-way valve is switched to feed the contents of the tube toward the optical cuvette into the mixing device 132.

Since both pumps are volumetric, the pump 124 operates at a speed lower than the speed of the pump 126. The difference in speeds corresponds to the number of samples taken and the ratio of the reagent or solvent stopping the reaction to the resulting sample.

A portion of the sample mixed with the reaction-terminating reagent and solvent in the mixing device 132 passes through a tube to a container for storing the analyzed sample 128 for analysis in the analyzer 138 (e.g., nuclear magnetic resonance, infrared, liquid chromatography, high performance liquid chromatography, gas chromatography etc.).

During the analysis, the temperature sensor 134 measures the temperature in the inner liquid chamber 104, and the controller 136 maintains the temperature of the optical cell 102 in the desired range. The temperature sensor 134 is in thermal contact with the camera 104. The controller 136 receives data from the temperature sensor 134 and adjusts the temperature in the optical cuvette 102.

Claims (1)

A system for analyzing the composition of technological streams of chemical industries, including an optical cuvette with optical elements, connected to an optical analyzer, consisting of a housing with an internal chamber having an input and output of the studied process stream, a pump, characterized in that it contains: - a device for measuring and controlling the temperature of the optical cuvette connected to the optical cuvette; - a mixing device connected to the pump; - a container for storing the analyzed sample, connected to the pump; - an analyzer connected to a container for storing the analyzed sample; - storage tank; - an additional pump connected to the mixing device and the storage tank, however, the optical cuvette additionally has a tap for sampling.

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