Constant-speed sampling variable-frequency tracking system of smoke instrument

Abstract

The invention discloses a constant-speed sampling variable-frequency tracking system of a smoke instrument, which is characterized in that a part of airflow is sucked and heated to remove water drops and gas fog to form measured gas, the measured gas is conveyed into a scattering pool, and a transmitting and receiving unit measures the intensity of scattered light so as to determine the concentration of smoke, so that the running reliability of important environmental protection equipment is improved; the device eliminates the existing potential safety hazard, enables the operation of a unit to be safe and reliable, solves the problems that the smoke instrument does not have a constant-speed tracking sampling function and the attraction error should not exceed + / -8%, and provides a reliable guarantee for the stability of environmental protection data during the operation of the unit. After the device is put into use, the smoke dust measured value is stable and reliable, the constant-speed sampling function meets the requirements of environmental protection specifications, and the transformation effect is verified. And the equipment completely meets the requirements of the national HJ75-76 standard during use.

Description

Technical Field

[0001] The invention relates to the technical field of smoke and dust meters, and in particular to a constant speed sampling frequency conversion tracking system of a smoke and dust meter. Background Art

[0002] The existing CEMS smoke monitoring equipment at the power plant outlet is the SICK FWE-200 model, which uses an extraction measurement method to measure smoke concentration during unit operation. The equipment has been in use for a long time, and the measurement accuracy is inaccurate. It also does not meet the requirements of the HJ75-76 Environmental Protection Equipment Specification for automatically tracking changes in flue gas flow rate and adjusting the sampling flow rate with the constant-speed tracking sampling function. Summary of the invention

[0003] In view of the problems existing in the above-mentioned conventional constant speed sampling frequency conversion tracking system of smoke and dust monitor, the present invention is proposed.

[0004] Therefore, the object of the present invention is to provide a constant speed sampling frequency conversion tracking system for a smoke and dust meter.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: comprising:

[0006] The suction part of the airflow is heated to remove water droplets and aerosols to form the measuring gas, which is then transported to the scattering cell. The transmitting and receiving units measure the intensity of the scattered light to determine the concentration of the smoke.

[0007] As a preferred solution of the constant speed sampling and variable frequency tracking system of the smoke dust monitor of the present invention, it also includes a hot cyclone separator, which is used to heat part of the sucked airflow into superheated gas.

[0008] As a preferred solution of the constant speed sampling and variable frequency tracking system of the smoke dust monitor of the present invention, it also includes a measuring gas probe, which is used to draw part of the airflow from the flue.

[0009] As a preferred solution of the constant speed sampling and variable frequency tracking system of the smoke and dust instrument of the present invention, it also includes an ejector for guiding the measuring gas back to the measuring gas probe.

[0010] As a preferred solution of the constant speed sampling and variable frequency tracking system of the smoke dust meter of the present invention, the ejector is connected to a fan unit, and the fan unit provides power for extracting smoke for the ejector.

[0011] As a preferred solution of the constant speed sampling and variable frequency tracking system of the smoke and dust meter of the present invention, the injector can transport part of the measuring gas to the transmitting and receiving unit.

[0012] As a preferred solution of the constant speed sampling and variable frequency tracking system of the smoke and dust meter of the present invention, wherein: a plurality of groups of heaters are installed on the hot cyclone separator.

[0013] As a preferred solution of the constant speed sampling and variable frequency tracking system of the smoke dust monitor of the present invention, it also includes a matrix flowmeter for measuring the differential pressure in the flue and converting the differential pressure signal into a flow rate signal.

[0014] As a preferred solution of the constant speed sampling and variable frequency tracking system of the smoke and dust meter of the present invention, it also includes a CEMS cabinet, which is used to transmit the flow velocity signal to the variable frequency control cabinet.

[0015] As a preferred solution of the constant speed sampling variable frequency tracking system of the smoke and dust meter of the present invention, the fan unit is controlled by a variable frequency control box.

[0016] The beneficial effects of the present invention are as follows: the reliability of the operation of important environmental protection equipment is improved, the existing safety hazards are eliminated, the operation of the unit is safe and reliable, and the problem that the smoke and dust meter does not have the function of constant speed tracking sampling and the suction error should not exceed ±8% is solved, which provides a reliable guarantee for the stability of environmental protection data during the operation of the unit;

[0017] Under normal operating conditions, when the flue gas velocity is greater than 5m / s, it has a constant speed sampling function, and the error is within the allowable range, which complies with the relevant technical specifications of HJ75-76; the smoke dust meter has higher measurement accuracy after the upgrade, and can more accurately reflect the changes in particle concentration during the operation of the unit, which is convenient for operators to make timely adjustments; after the transformation is completed, it will be compared and accepted for filing to ensure the accuracy of online particle data measurement;

[0018] The equipment has been aging, function loss and other difficult problems solved, and a lot of money has been saved. After commissioning, the actual measured value of smoke and dust is stable and reliable, and the isokinetic sampling function meets the requirements of environmental protection regulations. The transformation effect has been verified. The equipment fully meets the national HJ75-76 standard requirements during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0020] Figure 1 This is a flow chart of the flue gas flow rate signal transmission of the present invention. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0022] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0023] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0024] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0025] Example 1

[0026] A smoke meter constant speed sampling frequency conversion tracking system is provided, which includes: sucking part of the airflow, heating it to remove water droplets and aerosol to form a measuring gas, the measuring gas is transported to a scattering pool, and a transmitting and receiving unit measures the scattered light intensity to determine the concentration of the smoke.

[0027] Also included is a hot cyclone separator for heating a part of the sucked gas flow into superheated gas.

[0028] Also included is a test gas probe for extracting part of the gas flow from the flue.

[0029] Also included is an ejector which serves to guide the measuring gas back into the measuring gas probe.

[0030] The ejector is connected to a fan unit, which provides power for extracting smoke for the ejector.

[0031] The ejector can convey part of the measurement gas to the transceiver unit.

[0032] There are multiple groups of heaters installed on the hot cyclone separator.

[0033] The test gas probe is installed on the flange at an angle, the hot cyclone separator is installed with heater 1 and heater 2, the gas enters the scattering cell after heating, and the transmitting and receiving unit is provided with optical components, which include lenses for measuring light intensity, laser diodes, and laser diodes;

[0034] A part of the air flow is sucked from the flue using a measuring gas probe, heated to superheated gas in a hot cyclone separator, causing water droplets and aerosol to evaporate, and then enters the scattering cell as the measuring air flow. In the scattering cell, a transmitting and receiving unit is used to measure the scattered light intensity, which is used as a scale for determining smoke concentration;

[0035] After the measurement is completed, the ejector directs the measuring gas back into the measuring gas probe and flows back into the flue. The measuring gas is transported by the ejector, which is powered by the blower unit. At the same time, the ejector sends part of the airflow into the transmitting and receiving unit for cleaning and cooling the optical components.

[0036] Improve the reliability of the operation of important environmental protection equipment, eliminate the existing safety hazards, make the unit run safely and reliably, solve the problem that the smoke and dust meter does not have the function of isokinetic tracking sampling and the suction error should not exceed ±8%, and provide a reliable guarantee for the stability of environmental protection data during the operation of the unit;

[0037] Under normal operating conditions, when the flue gas velocity is greater than 5m / s, it has a constant speed sampling function, and the error is within the allowable range, which complies with the relevant technical specifications of HJ75-76; the smoke dust meter has higher measurement accuracy after the upgrade, and can more accurately reflect the changes in particle concentration during the operation of the unit, which is convenient for operators to make timely adjustments; after the transformation is completed, it will be compared and accepted for filing to ensure the accuracy of online particle data measurement;

[0038] The equipment has been aging, function loss and other difficult problems solved, and a lot of money has been saved. After commissioning, the actual measured value of smoke and dust is stable and reliable, and the isokinetic sampling function meets the requirements of environmental protection regulations. The transformation effect has been verified. The equipment fully meets the national HJ75-76 standard requirements during use.

[0039] Example 2

[0040] refer to Figure 1 This embodiment is different from the first embodiment in that it also includes a matrix flowmeter for measuring the differential pressure in the flue and converting the differential pressure signal into a flow rate signal.

[0041] Also included is a CEMS cabinet, which is used to transmit the flow rate signal to the frequency conversion control cabinet.

[0042] The fan unit is controlled by a frequency conversion control box.

[0043] The matrix flowmeter measures two sets of differential pressure signals in the flue. The system also includes a PLC controller connected to the matrix flowmeter. The two sets of differential pressure signals are converted into flow rate signals for transmission by the PLC. The flow rate signals are transmitted to the remote terminal unit control cabinet through the CEMS cabinet and then transmitted to the smoke meter frequency conversion control cabinet through the signal distributor.

[0044] The frequency conversion control cabinet receives the CEMS flow rate signal and controls the fan unit to automatically track the flue gas flow rate changes to adjust the sampling flow rate; the system can realize the constant speed tracking sampling function, and the constant speed tracking attraction error does not exceed ±8%.

[0045] The rest of the structure is the same as that of Example 1.

[0046] Example 3

[0047] refer to Figure 1 , this embodiment is different from the above embodiments in that: the system also includes an online upgrade function for improving measurement accuracy and accurately reflecting changes in particle concentration.

[0048] It also includes an automatic calibration function, which is developed and utilized to reduce the frequency of manual calibration. The smoke meter's constant speed tracking is inspected regularly. If a large constant speed deviation occurs, timely feedback is provided to analyze the cause and resolve it, such as whether the inverter power setting is too small, and whether the sampling pipeline is loose or leaking.

[0049] The system also includes an online upgrade function to improve measurement accuracy and accurately reflect changes in particle concentration. The system also includes a flow display unit to display sampling and flue gas flow rate, which is convenient for checking the real-time tracking of flue gas flow rate.

[0050] The fan unit consists of a high-pressure double impeller, a filter element and a sampling hose. The variable frequency fan filter element needs to be replaced regularly, and the sampling pipeline needs to be cleaned and maintained regularly.

[0051] The rest of the structure is the same as that of Example 2.

[0052] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0053] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0054] It will be appreciated that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will be a routine task of design, fabrication, and production for those of ordinary skill having the benefit of this disclosure without undue experimentation.

[0055] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A constant speed sampling frequency conversion tracking system for a smoke and dust instrument, characterized by: include, The suction part of the airflow is heated to remove water droplets and aerosols to form the measuring gas, which is then transported to the scattering cell. The transmitting and receiving units measure the intensity of the scattered light to determine the concentration of the smoke.

2. The constant speed sampling and frequency conversion tracking system of the smoke and dust monitor according to claim 1, characterized in that: Also included is a hot cyclone separator for heating a part of the sucked gas flow into superheated gas.

3. The constant speed sampling and frequency conversion tracking system of the smoke and dust instrument according to claim 2, characterized in that: Also included is a test gas probe for extracting part of the gas flow from the flue.

4. The smoke and dust instrument constant speed sampling frequency conversion tracking system as claimed in claim 3, characterized in that: Also included is an ejector which serves to guide the measuring gas back into the measuring gas probe.

5. The smoke and dust instrument constant speed sampling frequency conversion tracking system as claimed in claim 4, characterized in that: The ejector is connected to a fan unit, and the fan unit provides power for the ejector to extract smoke.

6. The constant speed sampling and variable frequency tracking system of the smoke and dust instrument according to claim 5, characterized in that: The ejector is able to convey part of the measurement gas to the transceiver unit.

7. The constant speed sampling and frequency conversion tracking system of the smoke and dust monitor according to claim 5 or 6, characterized in that: The hot cyclone separator is equipped with multiple groups of heaters.

8. The smoke and dust instrument constant speed sampling frequency conversion tracking system according to claim 7, characterized in that: Also included is a matrix flow meter for measuring differential pressure in the flue and converting the differential pressure signal into a flow rate signal.

9. The smoke and dust instrument constant speed sampling frequency conversion tracking system according to claim 8, characterized in that: Also included is a CEMS cabinet, which is used to transmit the flow rate signal to the frequency conversion control cabinet.

10. The smoke and dust monitor constant speed sampling frequency conversion tracking system according to claim 9, characterized in that: The fan unit is controlled by a frequency conversion control box.

Images