Oxygen monitoring and analyzing system

Abstract

The utility model discloses an oxygen monitoring and analyzing system which comprises a sampling unit, a pretreatment unit and an analyzing and calibrating unit, waste gas is sampled through a sampling probe and then transmitted to the pretreatment unit, and a sample gas part treated by the pretreatment unit enters the analyzing and calibrating unit for analyzing gas components and content. The pretreatment unit is connected with the sampling unit to obtain sample gas, then the sample gas is divided into two paths, the first emptying path is emptied after passing through a safety valve, sample gas flow in the first working path is cooled, purified and subjected to gas-liquid separation through a cyclone refrigeration tank, obtained dry gas is divided into two paths, and the second emptying path is emptied after passing through a bypass flowmeter; comprising discharge of liquid in the cyclone refrigeration tank, a switching valve is arranged in the second working path, and standard gas is controlled through the switching valve and used for analysis and calibration.

Description

Technical Field

[0001] The utility model belongs to chemical industry monitoring waste detection equipment, in particular to an oxygen monitoring and analysis system. Background Art

[0002] In industrial production, online oxygen monitoring systems play an important role. Changes in oxygen concentration directly affect the stability of the production process and product quality. By monitoring oxygen concentration in real time, production parameters can be adjusted in a timely manner to ensure smooth production and improve product quality and production efficiency.

[0003] The main problem with various existing oxygen detection equipment is that the detection results are of varying accuracy, especially the ability to detect trace oxygen content is insufficient. The main influencing factors include the drying, purification, voltage stabilization and temperature control of the sample gas. Some high-precision equipment also has problems such as complex structure. The utility model provides an oxygen monitoring and analysis system that can dry, purify, stabilize the voltage, cool the sample gas, etc., and can measure both trace oxygen and constant oxygen. Utility Model Content

[0004] Purpose of the utility model: The purpose of the utility model is to provide an oxygen monitoring and analysis system that can improve the oxygen detection capability and realize micro-oxygen detection, including solving the problems of the existing analysis device having a complex structure, inconvenient replacement, difficult maintenance, and difficulty in processing sample gas.

[0005] Technical solution: An oxygen monitoring and analysis system, which includes a sampling unit, a pretreatment unit and an analysis and calibration unit. The sampling unit samples the exhaust gas through a sampling probe and then transmits it to the pretreatment unit. The sample gas processed by the pretreatment unit enters the analysis and calibration unit for gas composition and content analysis. The pretreatment unit is connected to the sampling unit to obtain sample gas, and then divides the sample gas into two paths, namely a first vent path and a first working path; the first vent path is emptied after passing through a safety valve, and the sample gas in the first working path flows through a cyclone refrigeration tank for cooling, purification and gas-liquid separation;

[0006] The dry gas flowing out of the cyclone refrigeration tank is divided into two paths, namely the second vent path and the second working path. The second vent path is emptied after passing through the bypass flowmeter, including the discharge of the liquid in the cyclone refrigeration tank. A switching valve is provided in the second working path. The switching valve controls the sample gas to pass through the sample gas flowmeter for flow control and then enter the analysis and calibration unit for analysis and then emptied into the vent pipe. The calibration gas is connected through the switching valve to realize the measurement calibration of the analysis and calibration unit.

[0007] Furthermore, the sampling unit also includes a heating pipeline for heating transmission of the sample gas.

[0008] The sampling unit includes a root switch valve, the sampling tube is connected to the reactor gas supply pipeline through a connecting flange, and the root switch valve is arranged on the sampling tube to control the communication between the sampling tube and the reactor gas supply pipeline.

[0009] Furthermore, a sampling ball valve is provided at the connection between the pretreatment unit and the sampling unit, which is filtered and divided into gas paths through a T-type filter. An air pump is provided for supplying and transporting the sample gas, and is located on the first working path for air extraction.

[0010] The cyclone refrigeration tank realizes the second treatment of cooling and purifying the sample gas through instrument air refrigeration, and separates the gas and liquid. Then the sample gas enters the visual filter, and the visual filter discharges the liquid downward into the air drain valve to discharge the liquid.

[0011] A bypass filter is provided on the first working path for the third filtration of the sample gas.

[0012] Furthermore, the system includes a waste collection device for storing waste gas processed by the pretreatment unit and the analysis and calibration unit.

[0013] Furthermore, the pre-treatment unit is packaged and integrated in a cabinet, the cabinet is provided with an insulation layer, and steam heating is used in the cabinet.

[0014] The system includes a pressure gauge for detecting the pressure of the sample gas in the pipeline.

[0015] Furthermore, the system includes an instrument purge unit, which includes nitrogen, an air filter pressure reducing valve and a flow meter, and discharges the nitrogen to eliminate the influence of impurity gases in the analytical calibration unit.

[0016] Beneficial effects: Compared with the prior art, the system described in the present invention is provided with a branch for the sample gas, taking into account situations such as overpressure, and is also provided with a three-stage filtration to improve the detection accuracy of oxygen, which can be used for oxygen content detection in reactors and trace oxygen detection. On the other hand, the present invention adopts a modular design (instrument unit, pretreatment unit, electrical unit, insulation unit), which is easy to install and maintain. In the present invention, the sample gas is subjected to pressure reduction, voltage stabilization, purification, dehumidification, flow control and other treatments in the pretreatment unit to ensure that the sample gas sent to the instrument reaches ultra-clean, constant humidity, stable pressure, and the flow meets the requirements. The instrument analyzes the sample gas, displays the analysis value, outputs a standard 4-20mA current signal, and oxygen upper and lower limit alarm signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of the system of the present utility model. DETAILED DESCRIPTION

[0018] like Figure 1 As shown, the utility model provides an oxygen monitoring and analysis system for detecting oxygen content in chemical operations. According to the composition and function of the system, it can be divided into:

[0019] Sampling unit: includes a sampling tube 1 connected to the reactor gas supply pipe, the sampling tube 1 is connected through a connecting flange 3, and then a root switch valve 2 is provided near the gas supply pipe of the reactor, which can realize the overall control of sampling and facilitate the safe connection of subsequent components. After the root ball valve 2, a sampling valve 4 is further provided through the connecting flange 3. There is a sampling interface 5 on the sampling valve 4, thereby completing the gas sampling. For the sample gas, it is kept warm through a heating pipeline, and the gas with a certain temperature is easier to transmit, avoiding the impurities and other gas components contained in the gas from condensing in the sampling probe due to temperature drop and causing blockage.

[0020] Pretreatment unit: connected to the sampling unit through a pipeline, including a ball valve BV1, a T-type filter F01 and a solenoid valve SV01. After passing through the solenoid valve SV01, the sample gas is divided into two paths, namely the first venting path and the first working path;

[0021] The first vent line is equipped with a safety valve RV01, which then passes through an exhaust pipe for waste gas treatment, including waste gas collection or harmless discharge. This line is used to prevent excessive injection pressure from damaging the back-end instrument.

[0022] The first working path is equipped with a vacuum pump DP01. To prevent backflow, a needle valve NV01 regulates the sample gas flow. The sample gas then enters the cyclone refrigeration tank AC, which uses instrument air for cooling and purification. This process involves gas-liquid separation. An air filter and pressure reducing valve FR01 is installed on the instrument air supply path. The sample gas then enters the visual filter KV, which drains the liquid downward into the air drain valve DV (automatically drains to prevent gas backflow). The liquid is then removed, and the dry gas flows upward to the bypass filter BF01 (with a filter element) for a third filtration step.

[0023] The sample gas passing through the bypass filter BF01 is divided into two paths again, namely the second venting path and the second working path. The second venting path is a fast bypass gas path, which is used to shorten the lag time caused by the "dead space" of the gas sample transmission pipeline and other units. That is, part of the gas sample is quickly emptied after passing through the fast bypass flowmeter FI01 (diffusion flowmeter), and a one-way valve CV01 is placed behind it to prevent gas backflow. A switching valve BXV01 is set on the second working path to control the switching of the pipeline connected to the standard gas cylinder or the analytical calibration unit. Figure 1The system includes a bypass flowmeter FI02, which collects or discharges waste gas after testing and processing by the analytical calibration unit. Nitrogen is also required to evacuate the analytical calibration unit to prevent interference from residual gases. Therefore, a line connected to a nitrogen cylinder is provided, equipped with a bypass flowmeter FI03 for flow control and an air filter pressure reducing valve FR02. For the second working path, the switching valve BXV01 primarily switches between "operation" and "calibration." When in the "operation" position, the sample gas flowmeter controls the flow rate before entering the analyzer for analysis and ultimately draining the gas through the vent pipe.

[0024] The analysis and calibration unit includes an oxygen meter, a temperature sensor, a pressure transmitter, etc., and can also be measured using a magnetic oxygen sensor, etc.

[0025] The instrument purge unit consists of an air filter, a pressure reducing valve, and a flow meter.

Claims

1. An oxygen monitoring and analysis system, comprising a sampling unit, a pretreatment unit, and an analysis and calibration unit. The sampling unit samples exhaust gas through a sampling probe and then transmits the sample gas to the pretreatment unit. The sample gas processed by the pretreatment unit enters the analysis and calibration unit for analysis of gas composition and content. The system is characterized in that: The pre-processing unit is connected to the sampling unit to obtain the sample gas, and then the sample gas is divided into two paths, namely a first venting path and a first working path; the first venting path is emptied after passing through the safety valve, and the sample gas in the first working path passes through the cyclone refrigeration tank for cooling, purification and gas-liquid separation; The dry gas flowing out of the cyclone refrigeration tank is divided into two paths, namely the second vent path and the second working path. The second vent path is emptied after passing through the bypass flowmeter, including the discharge of the liquid in the cyclone refrigeration tank. A switching valve is provided in the second working path, and the standard gas is connected through the switching valve to realize the measurement calibration of the analysis and calibration unit.

2. The oxygen monitoring and analysis system according to claim 1, characterized in that: The sampling unit also includes a heating pipeline for heating and transmitting the sample gas.

3. The oxygen monitoring and analysis system according to claim 1 or 2, characterized in that: The sampling unit includes a root switch valve, the sampling tube is connected to the reactor gas supply pipeline through a connecting flange, and the root switch valve is arranged on the sampling tube to control the communication between the sampling tube and the reactor gas supply pipeline.

4. The oxygen monitoring and analysis system according to claim 1, characterized in that: A sampling ball valve is provided at the connection between the pretreatment unit and the sampling unit, which is filtered and divided into gas paths through a T-type filter. An air pump is provided for supplying and transporting the sample gas, and is located on the first working path for air extraction.

5. The oxygen monitoring and analysis system according to claim 1, characterized in that: The cyclone refrigeration tank realizes the second treatment of cooling and purifying the sample gas through instrument air refrigeration, and separates the gas and liquid. Then the sample gas enters the visual filter, and the visual filter discharges the liquid downward into the air drain valve to discharge the liquid.

6. The oxygen monitoring and analysis system according to claim 1, characterized in that: A bypass filter is provided on the first working path for the third filtration of the sample gas.

7. The oxygen monitoring and analysis system according to claim 1, characterized in that: The system includes a waste collection device for storing waste gas processed by the pre-processing unit and the analysis and calibration unit.

8. The oxygen monitoring and analysis system according to claim 1, characterized in that: The pre-treatment unit is packaged and integrated in a cabinet, the cabinet is provided with a heat-insulating layer, and steam heating is adopted in the cabinet.

9. The oxygen monitoring and analysis system according to claim 1, characterized in that: The system includes a pressure gauge for detecting the pressure of the sample gas in the pipeline.

10. The oxygen monitoring and analysis system according to claim 1, characterized in that: The system includes an instrument purge unit, which includes nitrogen, an air filter pressure reducing valve and a flow meter, and discharges the nitrogen to eliminate the influence of impurity gases in the analytical calibration unit.

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