Sensor and method for on-line measurement of oxygen-sulfur ratio in acid making process

Abstract

The invention relates to a sensor and a method for on-line measurement of an oxygen-sulfur ratio in an acid making process. The sensor comprises a temperature measuring element, a heating framework, a binding post, a detection gas chamber, a thermal conductivity probe, an oxygen potential probe, an outer cover, a base and a gas inlet and outlet interface. The thermal conductivity probe and the oxygen potential probe are arranged in the sensor at the same time, so that the effect that only one sensor is needed to measure the concentration of sulfur dioxide and oxygen at the same time and output electric signals, and the oxygen-sulfur ratio is directly displayed after processing is achieved. The process that a sulfur dioxide concentration analyzer and an oxygen concentration analyzer need to be installed at the same time for analysis and comparison in the past is greatly simplified. Installation is simple, measurement is accurate, and maintenance is convenient.

Description

Technical Field

[0001] The invention belongs to the field of environmental protection or environmental governance, and more specifically relates to a sensor and method for online measurement of oxygen-sulfur ratio in an acid production process. Background Art

[0002] Since the 1960s, the biggest technological progress in the SO2 conversion process in sulfuric acid production has been the use of a two-conversion, two-absorption process, referred to as two-conversion and two-absorption. Due to the various sources of raw gas containing SO2, in order to maximize the final conversion rate, a variety of processes have emerged in the two-conversion and two-absorption process. For example: the number of stages of the catalyst layer where the raw gas is converted before the first absorption tower is 3, and the number of stages thereafter is 2, which can be expressed as a "3+2" five-stage conversion; in addition, there are "3+1" four-stage conversion, "2+2" four-stage conversion, "2+1" three-stage conversion, etc. At present, most domestic acid-making devices use "3+1" four-stage conversion and "3+2" five-stage conversion. Regardless of the conversion method used, the oxygen-sulfur ratio is an important parameter, which can provide an important basis for the stable high conversion rate of the device and greatly improve the effective utilization of the catalyst.

[0003] Therefore, in the acid production process, it is usually necessary to measure the concentrations of sulfur dioxide and oxygen in the gas at the outlet of the fan online to convert the oxygen-sulfur ratio. In the past, the common method was to install a set of thermal conductivity sulfur dioxide analyzer and oxygen concentration analyzer, and convert the oxygen-sulfur ratio based on their respective data. The problems with this method include the 30kpa positive pressure at the outlet of the fan, which is easy to cause leakage when the gas to be measured passes through the sensor reflux system, errors caused by the differences in instruments of different brands, pretreatment required for each of the two systems, and complex installation methods. Summary of the invention

[0004] The purpose of the present invention is to solve the problems raised in the above background technology, and to provide a sensor and method for online measurement of oxygen-sulfur ratio in acid production process, so as to realize online measurement of oxygen-sulfur ratio of gas at the outlet of the blower. After the sensor described in the present invention is used, the differences of analyzers of different models are eliminated, and the sensor has the advantages of easier installation, more accurate data and less maintenance.

[0005] The present invention is implemented as follows: a sensor for online measurement of the oxygen-sulfur ratio in an acid production process, characterized in that it includes a base, a detection air chamber is provided on the base, and the detection air chamber is communicated with the air inlet and outlet interfaces at the lower part of the base; the detection air chamber is placed in a heating frame and fixed to the base through the heating frame; the detection air chamber has a built-in thermal conductivity probe and an oxygen potential probe, and the heating frame has a built-in temperature measuring element.

[0006] Furthermore, the thermal conductivity probe and the oxygen potential probe are connected to the terminal to output electrical signals.

[0007] Furthermore, the heating skeleton is an aluminum cylindrical structure, which provides a constant temperature environment for measurement.

[0008] Furthermore, the temperature measuring element is PT1000, which can perform high-precision monitoring within 1000 degrees Celsius.

[0009] Furthermore, the detection air chamber is made of stainless steel 316L and is provided with two air flow channels, each of which is equipped with a thermal conductivity probe and an oxygen potential probe.

[0010] Furthermore, the base and the air inlet and outlet ports are made of polytetrafluoroethylene.

[0011] Furthermore, the outer cover is made of galvanized aluminum casting.

[0012] Furthermore, all the above components are covered by an outer cover.

[0013] Furthermore, the outer cover is made of galvanized aluminum casting.

[0014] The present invention also provides a method for online measuring the oxygen-sulfur ratio at the inlet of a fan in an acid production process. The sensor capable of measuring the oxygen-sulfur ratio is installed at the inlet of the fan in the acid production process, and the gas is drawn into the drying tower by the negative pressure of the system.

[0015] Furthermore, the present invention is used for a method for online measurement of oxygen-sulfur ratio in an acid production process. In the acid production process, the gas at the outlet of the fan is blown into the air inlet interface at the bottom of the base by the fan, and the gas enters the detection air chamber through the base channel. The gas detected by the thermal conductivity probe and the oxygen potential probe is discharged from the air outlet interface at the bottom of the base. During the detection process, the temperature can be measured by the temperature measuring element built into the heating frame, and the thermal conductivity probe and the oxygen potential probe output the detected electrical signal through the terminal.

[0016] The beneficial effect of the present invention is that it provides a new type of sensor that is easy to install, accurate in measurement, and easy to maintain. By using the thermal conductivity probe and the oxygen potential probe installed in the sensor at the same time, only one sensor is needed to simultaneously measure the concentrations of sulfur dioxide and oxygen and output electrical signals, and the oxygen-sulfur ratio is directly displayed after processing. This greatly simplifies the process of simultaneous installation of a sulfur dioxide concentration analyzer and an oxygen concentration analyzer for analysis and comparison. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of the sensor according to the embodiment of the present invention.

[0018] Figure 2 It is a schematic diagram of the connection of the method of the embodiment of the present invention.

[0019] In the figure, 1-temperature measuring element; 2-base; 3-detection air chamber; 4-heating frame; 5-thermal conductivity probe; 6-oxygen potential probe; 7-connecting post; 8-inlet and outlet air interfaces; 9-outer cover. Implementation

[0020] The present invention is further described below in conjunction with the accompanying drawings and embodiments. Example 1

[0021] The embodiment provides a sensor for online measurement of oxygen-sulfur ratio in an acid production process, Figure 1 It mainly includes a base 2, on which a detection air chamber 3 is provided, which is communicated with the air inlet and outlet interfaces 8 at the lower part of the base; the detection air chamber 3 is placed in a heating frame 4 and fixed to the base 2 through the heating frame 4; the detection air chamber 3 has built-in thermal conductivity probe 5 and oxygen potential probe 6, and the heating frame 4 has built-in temperature measuring element 1, and all the above components are covered by an outer cover 9.

[0022] In the embodiment, the heating skeleton 4 is an aluminum cylinder, which can provide a constant temperature environment for measurement; the temperature measuring element 1 is a PT1000, which can perform high-precision monitoring within 1000 degrees Celsius.

[0023] In the embodiment, the material of the detection air chamber 3 is stainless steel 316L, and two air flow channels are provided therein, each of which has a thermal conductivity probe 5 and an oxygen potential probe 6 built therein; the material of the base 1 and the inlet and outlet air interfaces 8 are both polytetrafluoroethylene; the material of the outer cover 9 is galvanized cast aluminum. Example 2

[0024] The method for online measurement of oxygen-sulfur ratio at the fan inlet in the acid production process is shown in the attached Figure 2 The above-mentioned sensor capable of measuring the oxygen-sulfur ratio is installed at the inlet of the fan in the acid production process, and the gas is drawn into the drying tower by the system negative pressure.

[0025] The embodiment operates as follows: the gas at the outlet of the fan in the acid production process is blown into the air inlet interface at the bottom of the base 2 by the fan, and the gas enters the detection air chamber 3 through the base channel. The gas detected by the thermal conductivity probe 5 and the oxygen potential probe 6 is discharged from the air outlet interface at the bottom of the base 2. During the detection process, the temperature can be measured by the temperature measuring element 1 built into the heating frame 4, providing a constant temperature environment with a temperature higher than the gas to be measured for the measurement; the thermal conductivity probe 5 and the oxygen potential probe 6 output the detected electrical signal through the terminal 7.

[0026] The above embodiment method eliminates the potential safety hazard of leakage in the traditional method by installing a sensor with two built-in probes at the fan inlet, achieves the purpose of simultaneously measuring the concentrations of oxygen and sulfur dioxide, and outputs the oxygen-sulfur ratio at the same time, providing an important basis for ensuring a high conversion rate in the acid production process, and has the characteristics of safety, environmental protection, accurate measurement, easy installation, and low maintenance.

Claims

1. A sensor for online measurement of oxygen-sulfur ratio in an acid production process, characterized in that The invention comprises a base, on which a detection air chamber is arranged, which is communicated with the air inlet and outlet interfaces at the bottom of the base; the detection air chamber is arranged in a heating frame and fixed on the base through the heating frame; a thermal conductivity probe and an oxygen potential probe are built in the detection air chamber, and a temperature measuring element is built in the heating frame.

2. A sensor for online measurement of oxygen-sulfur ratio in an acid production process according to claim 1, characterized in that: The thermal conductivity probe and the oxygen potential probe are connected to the terminal to output electrical signals.

3. A sensor for online measurement of oxygen-sulfur ratio in an acid production process according to claim 1, characterized in that: The heating frame is in the shape of an aluminum cylinder.

4. A sensor for online measurement of oxygen-sulfur ratio in an acid production process according to claim 1, characterized in that: The temperature measuring element is PT1000, which performs high-precision monitoring within 1000 degrees Celsius.

5. A sensor for online measurement of oxygen-sulfur ratio in an acid production process according to claim 1, characterized in that: The detection air chamber made of 316L stainless steel is equipped with two air flow channels, one with a thermal conductivity probe and the other with an oxygen potential probe.

6. A sensor for online measurement of oxygen-sulfur ratio in an acid production process according to claim 1, characterized in that: The base and the air inlet and outlet interfaces are made of polytetrafluoroethylene.

7. A sensor for online measurement of oxygen-sulfur ratio in an acid production process according to any one of claims 1 to 6, characterized in that: All components are covered by an outer cover.

8. A sensor for online measurement of oxygen-sulfur ratio in an acid production process according to claim 7, characterized in that: The outer cover is made of galvanized aluminum casting.

9. A method for online measurement of oxygen-sulfur ratio at the fan inlet in an acid production process, characterized in that A sensor as claimed in any one of claims 1 to 8 is installed at the inlet of the fan in the acid production process, and the gas is drawn into the drying tower by the negative pressure of the system.

10. The method according to claim 9, characterized in that In the acid production process, the gas at the fan outlet is blown into the air inlet interface at the bottom of the base by the fan, and the gas enters the detection air chamber through the base channel. The gas detected by the thermal conductivity probe and the oxygen potential probe is discharged from the air outlet interface at the bottom of the base. During the detection process, the temperature is measured by the temperature measuring element built into the heating frame, and the thermal conductivity probe and the oxygen potential probe output the detected electrical signal through the terminal.

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