Flue gas sampling device and flue gas emission continuous monitoring system

Abstract

The utility model relates to a flue gas sampling device and a flue gas emission continuous monitoring system, the flue gas sampling device comprises a sampling probe rod, the sampling probe rod comprises a hollow inner rod and an outer rod sleeved outside the hollow inner rod, a heating wire is arranged between the hollow inner rod and the outer rod, and the heating wire is wound outside the hollow inner rod; a sintered filter element is arranged at the air outlet end of the hollow inner rod and located in the hollow inner rod. A gas outlet joint and a calibration gas joint are arranged at the gas outlet end of the hollow inner rod; a gas path of the gas outlet joint is communicated with a sampling gas path of the hollow inner rod through a sintered filter element; the calibration gas joint is communicated with a sampling gas path of the hollow inner rod so as to be communicated with a gas path of the gas outlet joint through the sintered filter element; and the calibration gas inlet pipeline is hermetically connected with the calibration gas joint. The probe rod and the probe are combined into a whole, an integrated heating structure is adopted, heating temperature distribution is uniform, a one-pipe sampling mode is designed, a sampling mode that a straight pipe is configured with a sintered filter element is adopted, dead volume is avoided, and therefore sampling accuracy and real-time performance are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of sampling, and in particular relates to a flue gas sampling device and a flue gas emission continuous monitoring system. Background Art

[0002] The continuous emission monitoring system (CEMS) is a commonly used pollutant emission metering instrument. It has completely replaced manual monitoring and is widely used in the monitoring and management of fixed pollution sources. The flue gas sampling probe, as a CEMS sample collection and transmission device, realizes non-blocking automatic continuous sampling without changing the composition and chemical properties of the sample gas, and uses physical methods to separate smoke and filter dust.

[0003] Flue gas sampling probes are suitable for sampling gases from fixed pollution sources. They are widely used in flue gas filtration sampling in the power industry, metallurgical industry, cement kiln industry, and volatile organic gas VOCs sampling in various industries. The working conditions of fixed pollution source gases are mostly high temperature, high dust, and highly corrosive environments. Therefore, common sampling probes need to have functions such as high temperature heating, regular backwashing, and multi-stage filtration. However, most sampling probes now have the following shortcomings: 1. The probe rod and the probe are heated separately, which is easy to cause uneven heating temperature distribution and relatively complex insulation measures; 2. There is a lot of "dead volume" inside the sampling probe, resulting in serious residue inside the sampling probe. The collected sample gas may enter the online analyzer of the continuous monitoring system and cause uneven sample gas collection, thereby affecting the measurement accuracy of the analyzer; 3. The standard gas is required to pass through the probe rod filter element during the full process calibration. Conventional sampling probes need to be equipped with a ball valve to control the gas flow path, and the full process calibration pipeline is led out on the probe rod, which makes the gas path complicated and increases the dead volume area; 4. The probe part is basically heated by devices such as cast aluminum heating blocks, and it is wrapped with insulation to make it bulky, heavy, and inconvenient to install and maintain. Utility Model Content

[0004] Based on the above-mentioned shortcomings and deficiencies in the prior art, one of the purposes of the present invention is to at least solve one or more of the above-mentioned problems in the prior art. In other words, one of the purposes of the present invention is to provide a flue gas sampling device and a flue gas emission continuous monitoring system that meet one or more of the above-mentioned needs.

[0005] In order to achieve the above utility model purpose, the utility model adopts the following technical solutions:

[0006] A flue gas sampling device, comprising:

[0007] The sampling probe comprises a hollow inner rod and an outer rod sleeved outside the hollow inner rod, a heating wire is arranged between the hollow inner rod and the outer rod, and the heating wire is wound outside the hollow inner rod; wherein a sintered filter element is arranged at the gas outlet end of the hollow inner rod, and the sintered filter element is located inside the hollow inner rod; the gas outlet end of the hollow inner rod has a gas outlet joint and a calibration gas joint, and the gas path of the gas outlet joint is connected with the sampling gas path of the hollow inner rod through the sintered filter element; the calibration gas joint is connected with the sampling gas path of the hollow inner rod, and is connected with the gas path of the gas outlet joint through the sintered filter element;

[0008] The calibration gas inlet pipeline is sealed and connected to the calibration gas connector.

[0009] As a preferred solution, the heating wires are wound around the hollow inner rod at equal distances.

[0010] As a preferred solution, the outside of the hollow inner rod is coated with a high-temperature insulating tape for insulation between the hollow inner rod and the heating wire.

[0011] As a preferred solution, a temperature sensor and a temperature control switch are provided between the high-temperature insulating tape and the heating wire, and the temperature control switch is electrically connected to the heating wire.

[0012] As a preferred solution, thermal insulation cotton is wrapped around the outside of the heating wire.

[0013] As a preferred solution, the air inlet end of the hollow inner rod is connected to the port of the outer rod via a flange, the inner wall of the outer rod is threadedly connected to the flange, and the inner wall of the flange is sealingly connected to the hollow inner rod.

[0014] As a preferred solution, side sealing is achieved between the inner wall of the flange and the hollow inner rod through a plurality of sealing rings distributed axially at intervals.

[0015] As a preferred solution, the flange has an internal thread as a transfer interface.

[0016] As a preferred solution, the calibration air intake pipeline is provided with a solenoid valve.

[0017] The utility model also provides a smoke emission continuous monitoring system, which adopts the smoke sampling device as described in any of the above schemes to sample the smoke emission.

[0018] Compared with the prior art, the utility model has the following beneficial effects:

[0019] (1) The probe rod and the probe head of the utility model are integrated into one body and adopt an integrated heating structure, so the heating temperature is evenly distributed and the heat preservation structure is easy to lay out;

[0020] (2) The utility model designs a one-tube sampling method to solve the problem that the multiple diameter changes and transitions of conventional sampling probes increase the internal "dead volume", and part of the flue gas will idle inside the "dead volume", resulting in a decrease in sampling accuracy. The method uses a straight tube with a sintered filter element to eliminate transitions and diameter changes, thereby improving the accuracy and real-time performance of sampling.

[0021] (3) The conventional sampling probe adopts a probe rod opening and uses a high-temperature ball valve and other complex devices to achieve full-process calibration. The sampling probe rod opening of the present application allows the calibration standard gas to directly enter the probe rod, and a sintered filter element is used at the tail of the probe rod for sampling, thereby achieving full-process calibration of the sintered filter element of the sampling probe rod;

[0022] (4) The high-temperature insulating tape of the utility model can prevent leakage caused by heating damage, and has good safety; in addition, the setting of the temperature control switch has an over-temperature protection function, which can protect the internal components from damage in abnormal working conditions;

[0023] (5) The utility model adopts a sealing ring side sealing method, which is convenient for maintenance and reserves space for heating expansion;

[0024] (6) The flange at the air inlet end of the sampling probe of the utility model adopts an internal thread design, and can be equipped with a filter element, an extended sampling rod, etc., which is applicable to a wider range of working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a smoke sampling device according to Embodiment 1 of the present utility model;

[0026] Figure 2 yes Figure 1 A cross-sectional view of the AA portion in FIG.

[0027] Figure 3 yes Figure 2 A magnified view of part I in FIG.

[0028] Figure 4 yes Figure 3 Enlarged view of Part II in . DETAILED DESCRIPTION

[0029] In order to more clearly illustrate the embodiments of the utility model, the specific implementation methods of the utility model will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0030] Embodiment 1:

[0031] like Figure 1-4As shown, the smoke sampling device of this embodiment includes a sampling probe 1 and a calibration air inlet pipeline 2.

[0032] Specifically, the sampling probe 1 includes a hollow inner rod 11 and an outer rod 12 sleeved outside the hollow inner rod 11 . The radial spacing between the hollow inner rod 11 and the outer rod 12 is matched to facilitate accommodating other devices.

[0033] A heating wire 13 is provided between the hollow inner rod 11 and the outer rod 12. Specifically, the hollow inner rod 11 of the present embodiment is made of stainless steel, and its outer periphery is coated with a high-temperature insulating tape, which is used for insulation between the hollow inner rod 11 and the heating wire 13 and balances the heating of the heater; the heating wire 13 is wound around the high-temperature insulating tape at equal distances, and the heating wire 13 is wound with thermal insulation cotton; wherein, a temperature sensor and a temperature control switch are provided between the high-temperature insulating tape and the heating wire 13, and the temperature control switch is electrically connected to the heating wire. The temperature control switch controls the sampling temperature of the sampling probe, and the temperature control switch can ensure over-temperature protection, and the outside of the heating wire is wrapped with thermal insulation cotton for thermal insulation treatment. In addition, a lead hole 120 is opened on one side of the air inlet end of the outer rod 12 to facilitate the wiring of the temperature control switch and the temperature sensor.

[0034] In this embodiment, a sintered filter element 3 is fixedly installed (such as welded) in the inner cavity of the air outlet end of the hollow inner rod 11, that is, the sintered filter element 3 is located inside the hollow inner rod 11, which can avoid both switching and dead volume.

[0035] In addition, the air outlet end of the hollow inner rod 11 has an air outlet connector 4 and a calibration gas connector 5. The air path of the air outlet connector 4 is connected to the sampling air path of the hollow inner rod 11 (i.e., the inner cavity of the hollow inner rod) through the sintered filter element 3; the calibration gas connector 5 is connected to the sampling air path of the hollow inner rod 11, so as to be connected to the air path of the air outlet connector 4 through the sintered filter element 3; that is, the flue gas sampling or the calibration standard gas sampling must pass through the sintered filter element 3 to enter the air outlet connector for detection.

[0036] The calibration air inlet pipeline 2 of this embodiment is sealed and connected to the calibration gas connector 5, which is convenient for sampling the calibration standard gas. The calibration air inlet pipeline 2 is provided with a solenoid valve 20, which is convenient for intelligently controlling the on and off of the calibration air inlet pipeline 2.

[0037] In this embodiment, the air inlet end of the hollow inner rod 11 is connected to the air inlet port of the outer rod 12 via a flange 6, the inner wall of the outer rod 12 is threadedly connected to the flange 6, and the inner wall of the flange 6 is sealed to the outer wall of the hollow inner rod 11. Specifically, the inner wall of the flange 6 and the hollow inner rod 11 are sealed by two sealing rings 7 axially spaced apart; the double-layer sealing design can cope with different working conditions to ensure air tightness; moreover, the heating and cooling of the probe rod will cause the hollow inner rod to shrink and expand, and the side seal at the air inlet end reserves enough space for expansion.

[0038] The flange 6 of this embodiment has an internal thread 60, which serves as a transfer interface to facilitate installation of components such as a filter element and an extended sampling rod.

[0039] The flue gas emission continuous monitoring system of the present embodiment adopts the above-mentioned flue gas sampling device to sample the flue gas emission, thereby effectively improving the accuracy and stability of the continuous monitoring of the flue gas emission.

[0040] Embodiment 2:

[0041] The difference between the smoke sampling device of this embodiment and that of embodiment 1 is that:

[0042] The method of fixing the hollow inner rod and the outer rod with flanges is replaced by other commonly used methods, such as collars, etc.;

[0043] For other structures, please refer to Example 1;

[0044] The flue gas emission continuous monitoring system of the present embodiment adopts the above-mentioned flue gas sampling device to sample the flue gas emission, thereby effectively improving the accuracy and stability of the continuous monitoring of the flue gas emission.

[0045] Embodiment 3:

[0046] The difference between the smoke sampling device of this embodiment and that of embodiment 1 is that:

[0047] The hollow inner rod is made of non-conductive material, so the high-temperature insulating tape can be omitted;

[0048] For other structures, please refer to Example 1;

[0049] The flue gas emission continuous monitoring system of the present embodiment adopts the above-mentioned flue gas sampling device to sample the flue gas emission, thereby effectively improving the accuracy and stability of the continuous monitoring of the flue gas emission.

[0050] The above description is only a detailed description of the preferred embodiments and principles of the present invention. For ordinary technicians in this field, according to the ideas provided by the present invention, there will be changes in the specific implementation methods, and these changes should also be regarded as the protection scope of the present invention.

Claims

1. A flue gas sampling device, It is characterized in that include: The sampling probe comprises a hollow inner rod and an outer rod sleeved outside the hollow inner rod, a heating wire is arranged between the hollow inner rod and the outer rod, and the heating wire is wound outside the hollow inner rod; wherein a sintered filter element is arranged at the gas outlet end of the hollow inner rod, and the sintered filter element is located inside the hollow inner rod; the gas outlet end of the hollow inner rod has a gas outlet joint and a calibration gas joint, and the gas path of the gas outlet joint is connected with the sampling gas path of the hollow inner rod through the sintered filter element; the calibration gas joint is connected with the sampling gas path of the hollow inner rod, and is connected with the gas path of the gas outlet joint through the sintered filter element; The calibration gas inlet pipeline is sealed and connected to the calibration gas connector; The air inlet end of the hollow inner rod is connected to the port of the outer rod through a flange, the inner wall of the outer rod is threadedly connected to the flange, and the inner wall of the flange is sealed to the hollow inner rod; Side sealing is achieved between the inner wall of the flange and the hollow inner rod through a plurality of sealing rings distributed at intervals in the axial direction.

2. The smoke sampling device according to claim 1, It is characterized in that The heating wires are wound around the hollow inner rod at equal distances.

3. The smoke sampling device according to claim 2, It is characterized in that The outside of the hollow inner rod is coated with a high-temperature insulating tape, which is used for insulation between the hollow inner rod and the heating wire.

4. The smoke sampling device according to claim 3, It is characterized in that A temperature sensor and a temperature control switch are arranged between the high-temperature insulating tape and the heating wire, and the temperature control switch is electrically connected to the heating wire.

5. The smoke sampling device according to claim 3, It is characterized in that The outside of the heating wire is wrapped with heat-insulating cotton.

6. The smoke sampling device according to claim 1, It is characterized in that The flange has an internal thread as a transfer interface.

7. The smoke sampling device according to claim 1, It is characterized in that The calibration air intake pipeline is provided with a solenoid valve.

8. A continuous monitoring system for flue gas emissions, It is characterized in that The flue gas emission is sampled using the flue gas sampling device as described in any one of claims 1 to 7.

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