Online detection analyzer for oxygen concentration of flue gas of garbage incinerator and garbage incinerator

Abstract

The utility model discloses a garbage incinerator flue gas oxygen concentration online detection analyzer and a garbage incinerator. The analyzer comprises a filter unit, a cooling unit, a gas-water separation unit, a heating unit, an oxygen concentration detection unit and an online correction unit, the filtering unit, the cooling unit, the gas-water separation unit, the heating unit and the oxygen concentration detection unit are sequentially connected through pipelines; the online correction unit comprises a plurality of standard oxygen tanks, and oxygen with different concentrations is stored in the standard oxygen tanks; and each standard oxygen tank is connected with the oxygen concentration detection unit. The oxygen concentration detection device has the advantages of accuracy and reliability in oxygen concentration detection and the like.

Description

Technical Field

[0001] This utility model mainly relates to the field of waste incineration technology, specifically to an online oxygen concentration detection and analysis instrument for waste incinerator flue gas and a waste incinerator. Background Technology

[0002] Currently, the instruments used for online oxygen concentration detection are mainly zirconia probes. These probes utilize the electro-oxygen properties of zirconia to detect the percentage of oxygen concentration in flue gas compared to that in the air. This type of analyzer is suitable for detecting and calibrating oxygen concentration in flue gas from various industrial furnaces and kilns, offering short response time and high measurement accuracy.

[0003] Because zirconia uses platinum as its electrode, and flue gas contains various dusts and harmful gases such as sulfides, the platinum electrode of the zirconia tube can easily become clogged and poisoned. Generally, zirconia tubes have a relatively short lifespan, and after a period of use, their measurement accuracy decreases, drift becomes significant, oxygen detection becomes inaccurate, and they may even become completely ineffective.

[0004] Furthermore, in boiler scenarios (such as waste incinerators), where zirconia probes are mainly used, most boilers lack corresponding flue gas composition detection and automatic control technologies. Their air distribution and fuel distribution rely entirely on workers' experience. Often, fuel distribution is simply based on the temperature required in the boiler, with manual control of the fuel valves. However, there is no control over the fans; they operate only at the power frequency. The control is merely an open-loop control, which is far from sufficient to meet energy-saving goals in increasingly complex combustion systems. Utility Model Content

[0005] To address the technical problems existing in the prior art, this utility model provides an online detection and analysis instrument for accurate and reliable detection of oxygen concentration in flue gas from a waste incinerator, as well as a waste incinerator.

[0006] To solve the above-mentioned technical problems, the technical solution proposed by this utility model is as follows:

[0007] An online oxygen concentration detection and analysis instrument for waste incinerator flue gas includes a filtration unit, a cooling unit, a gas-liquid separation unit, a heating unit, an oxygen concentration detection unit, and an online calibration unit. The filtration unit, cooling unit, gas-liquid separation unit, heating unit, and oxygen concentration detection unit are connected sequentially via pipelines. The online calibration unit includes multiple standard oxygen cylinders, each storing oxygen at different concentrations. Each standard oxygen cylinder is connected to the oxygen concentration detection unit.

[0008] As a further improvement to the above technical solution:

[0009] It also includes an air duct backflush unit, which includes an air compressor and a backflush solenoid valve; the output end of the air compressor is connected to the output end of the filter unit via a pipeline; the backflush solenoid valve is located on the corresponding pipeline.

[0010] The filtration unit is a flue gas filter; the cooling unit is a cooler; and the heating unit is a heater.

[0011] The gas-water separation unit includes a gas-water separation tank, a peristaltic pump, and a three-way valve; the peristaltic pump is connected to the bottom of the gas-water separation tank through a pipe, and the three-way valve is located on the corresponding pipe.

[0012] The oxygen concentration detection unit includes multiple oxygen concentration sensors and multiple air pumps; each oxygen concentration sensor corresponds to one air pump; each oxygen concentration sensor is connected to the heating unit via its corresponding air pump.

[0013] A waste incinerator includes a boiler, wherein the boiler is equipped with an online oxygen concentration detection and analysis instrument for waste incinerator flue gas as described above.

[0014] As a further improvement to the above technical solution:

[0015] The boiler body is equipped with multiple burners, one end of which is connected to a fuel valve, and the other end of which is connected to the boiler furnace.

[0016] The boiler has a flue at the tail end, and the heat exchanger is installed in the flue.

[0017] An air valve is installed at the air inlet of the burner. The air valve is connected to the outlet of the heat exchanger via a hot air duct. The inlet of the heat exchanger is connected to a blower with an air intake via a cold air duct. There is a bypass valve between the cold air duct and the hot air duct.

[0018] The signal output terminal of the oxygen concentration detection unit is connected to the acquisition signal input terminal of the controller. The control display terminal of the controller is connected to the human-machine interface operation display. The output terminal of the controller is connected to the control terminal of the speed controller. The other end of the speed controller is connected to the blower.

[0019] A temperature sensor is installed inside the boiler furnace, and the temperature sensor is connected to the fuel valve.

[0020] Compared with the prior art, the advantages of this utility model are:

[0021] This utility model discloses an online oxygen concentration detection and analysis instrument for waste incinerator flue gas. The flue gas is extracted from the flue, subjected to two-stage filtration, and cooled to remove moisture and dust, reducing the concentration of sulfuric acid mist and sulfurous acid mist. The purified flue gas then passes through an improved zirconia sensor to detect oxygen concentration. Due to the high degree of flue gas purification, the lifespan of the zirconia tube and measurement accuracy are improved. To ensure long-term accurate detection, the instrument is equipped with a backflushing unit and an online calibration unit to guarantee accurate and reliable detection. The oxygen concentration sensor and air pump are all used in a one-for-one backup configuration to ensure the stability of the analyzer's operation. Attached Figure Description

[0022] Figure 1 This is a block diagram of the online flue gas oxygen concentration analyzer of this utility model in an embodiment.

[0023] Figure 2 This is a block diagram of the boiler system of this utility model in an embodiment.

[0024] Legend: 1. Filtration unit; 2. Cooling unit; 3. Gas-water separation unit; 301. Gas-water separator; 302. Peristaltic pump; 303. Three-way valve; 4. Heating unit; 5. Oxygen concentration detection unit; 501. Oxygen concentration sensor; 502. Air pump; 6. Online calibration unit; 601. Standard oxygen tank; 602. Manual valve; 603. Solenoid valve; 604. Pressure reducing valve; 7. Air duct backflush unit; 701. Air compressor; 702. Backflush solenoid valve; 8. Flow meter; 9. Boiler; 10. Flue; 11. Blower; 12. Air valve; 13. Fuel valve; 14. Burner; 15. Sampling tube; 16. Display; 17. Controller; 18. Frequency converter; 19. Three-phase AC power supply. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0026] like Figure 1 As shown, the online flue gas oxygen concentration analyzer provided in this embodiment of the present invention includes a filtration unit 1 (such as a filter), a cooling unit 2 (such as a cooler), a gas-water separation unit 3 (such as a gas-water separation tank 301), a heating unit 4 (heater), an oxygen concentration detection unit 5 (such as an oxygen concentration sensor 501), and a micro flow meter 8.

[0027] The online calibration unit 6 includes multiple standard oxygen cylinders 601, each containing oxygen of different concentrations. Each standard oxygen cylinder 601 is connected to the oxygen concentration detection unit 5. Each standard oxygen cylinder 601 is connected to the oxygen concentration sensor 501 via a manual valve 602, a solenoid valve 603, and a pressure reducing valve 604 in sequence. The oxygen concentration sensor 501 is calibrated periodically to avoid signal drift of the oxygen concentration sensor 501 during long-term online oxygen concentration monitoring, which could lead to inaccurate detection data.

[0028] In practical applications, the flue gas originates from the exhaust gas discharged from the tail section or flue duct 10 of various industrial boilers. The filter is a precision instrument with a stainless steel sleeve, and its main function is to collect and filter the flue gas. After passing through the filter, the flue gas enters the cooler, where it undergoes drying, desulfurization, dehumidification, and cooling to become a sample gas with a high degree of cleanliness and appropriate temperature. Next, the condensate in the sample gas enters the bottom of the gas-liquid separator 301. The three-way valve 303 is opened, and then the peristaltic pump 302 is activated, allowing the water in the gas-liquid separator 301 to be discharged. The sample gas then enters the heater and is heated into superheated gas. Under the action of the micro-pump 502, the sample gas enters the oxygen concentration sensor 501 through the opened solenoid valve 603.

[0029] The processed clean sample gas is sent to the oxygen concentration sensor 501 in the detection area. The sensor can perform non-electrical conversion of the sample gas oxygen concentration and convert it into a stable and reliable signal source. The oxygen concentration sensor 501 can process the collected sample gas oxygen concentration signal and send it to the display 16 or transmit it to the industrial boiler 9 control system to adjust the speed of the blower 11. After passing through the oxygen concentration sensor 501, the sample gas is discharged by the micro flow meter 8.

[0030] During the use of the analyzer, the micropores in the filter may become clogged. In this case, the air duct backflush unit 7 of the analyzer can be opened. The air duct backflush unit 7 includes an air compressor 701 and a backflush solenoid valve 702. The output end of the air compressor 701 is connected to the output end of the filter via the solenoid valve 702. During use, opening the backflush solenoid valve 702 and starting the micro air compressor 701 will allow compressed air to sequentially purge the air supply pipe and filter through the backflush solenoid valve 702, thereby maintaining the normal operation of the system.

[0031] When the oxygen concentration sensor 501 needs calibration, simply open the pressure reducing valve 604, use the standard oxygen cylinder 601 with a volume concentration of n%, and open the corresponding manual valve 602 and solenoid valve 603. The standard concentration oxygen in the standard oxygen cylinder 601 can then enter the oxygen concentration sensor 501. The output signal is processed and compared with the corresponding standard oxygen concentration signal. If there is a difference, automatic adjustment is performed, thereby ensuring the authenticity of the detection data and improving the reliability of oxygen concentration measurement.

[0032] Because N standard oxygen tanks 601 are configured, with internal standard oxygen concentrations ranging from 1% to N% (the standard oxygen concentrations are all volume percentages of oxygen), they can be used for multi-point comparison, thereby further improving the reliability of system signal data detection.

[0033] This utility model discloses an online oxygen concentration detection and analysis instrument for waste incinerator flue gas. The flue gas is extracted from the flue duct 10, subjected to two-stage filtration, and cooled to remove moisture and dust, reducing the concentration of sulfuric acid mist and sulfurous acid mist. The purified flue gas then passes through an improved zirconia sensor to detect oxygen concentration. Due to the high degree of flue gas purification, the lifespan of the zirconia tube and measurement accuracy are improved. To ensure long-term accurate detection, the instrument is equipped with a backflushing unit 7 and an online calibration unit 6, guaranteeing accurate and reliable detection. The oxygen concentration sensor 501 and the air pump 502 are used in a one-in-one standby configuration to ensure the stability of the analyzer's operation.

[0034] like Figure 2As shown, this embodiment of the invention also provides a waste incinerator, including a boiler 9. The boiler 9 is equipped with an online oxygen concentration detection and analysis instrument for waste incinerator flue gas as described above. Multiple burners 14 are mounted on the boiler body. One end of each burner 14 is connected to a fuel valve 13, and the other end is connected to the furnace of the boiler 9. A flue 10 is located at the tail end of the boiler 9, and a heat exchanger is installed in the flue 10. An air valve 12 is installed at the air inlet of each burner 14. The air valve 12 is connected to the outlet of the heat exchanger via a hot air pipe. The inlet of the heat exchanger is connected to a blower 11 (or one or more) with an air intake via a cold air pipe. A bypass valve is located between the cold air pipe and the hot air pipe. An oxygen sensor, which can be a high-temperature oxygen sensor, is installed inside the boiler 9. The signal output terminal of the oxygen sensor is connected to the signal input terminal of a controller 17. The control display terminal of the controller 17 is connected to a human-machine interface display 16, and the output terminal of the controller 17 is connected to the control terminal of a speed controller. The other end of the speed controller is connected to the blower 11. The speed controller and blower 11 can be connected by mechanical connection or cable connection. The oxygen sensor directly measures the oxygen content in the flue gas inside the boiler 9 and converts it into an electrical signal, which is sent to the controller 17 and displayed on the human-machine interface display 16. When the oxygen sensor detects that the oxygen content in the flue gas inside the boiler 9 is too high compared to the set value, i.e., the air supply is excessive, the oxygen sensor sends the signal to the controller 17 for comparison, calculation, or processing before sending it to the speed controller. The speed controller then sends a speed regulation signal to the blower 11 to adjust its speed (decelerate and reduce airflow) until the blower 11 is adjusted to a speed where the oxygen content in the flue gas inside the kiln measured by the oxygen sensor is too low compared to the set value, i.e., the air supply is insufficient. The oxygen sensor then sends the signal to the controller 17 for comparison, calculation, or processing before sending it to the speed controller. The speed controller then sends a speed regulation signal to the blower 11 to adjust its speed (increase speed and increase airflow) until the blower 11 is adjusted to a speed where the oxygen content in the flue gas inside the boiler 9 measured by the oxygen sensor is within the set range.

[0035] A flue gas sampling tube 15 is inserted into the tail section or flue 10 of the controlled industrial boiler 9. Driven by an air pump, the flue gas is drawn in through the inlet of the sampling tube 15, cooled, dehumidified, and purified before entering the measuring chamber. It is then pumped back into the flue 10. Gas sensors in the measuring chamber convert the detected gas concentration values ​​into standard analog electrical signals, which are then input into the control system. These signals are compared and calculated with preset values ​​in the control system. After processing, the signals are sent to the speed control device, which controls the speed of the blower 11 and the induced draft fan according to a corresponding ratio, thereby achieving reasonable air distribution and scientific combustion.

[0036] The combustion control system of industrial boiler 9 mainly targets the amount of oxygen in the flue gas after combustion in the heating furnace. Based on the different production processes of boiler 9, the program is set to automatically adjust the air distribution of the main air duct linearly to achieve reasonable air distribution for combustion, improve combustion quality, and maximize the reduction of energy consumption.

[0037] The system implements bidirectional control: one closed-loop control for temperature and the other for oxygen concentration. This achieves accurate control through both feed and air distribution, resulting in faster response times and enhanced system reliability and adjustability. When the temperature inside boiler 9 is too low, the opening of fuel valve 13 is increased to meet production needs, while the fan speed adjusts to the oxygen concentration in the flue gas, ensuring combustion efficiency. Similarly, when the temperature inside boiler 9 is too high, the opening of fuel valve 13 is decreased, and the fan speed adjusts to the oxygen concentration in the flue gas, maintaining a low-oxygen combustion state to achieve energy saving and emission reduction.

[0038] The above are merely preferred embodiments of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are within its protection scope. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should be considered within its protection scope.

Claims

1. An online oxygen concentration detection and analysis instrument for waste incinerator flue gas, characterized in that, The system includes a filtration unit (1), a cooling unit (2), a gas-water separation unit (3), a heating unit (4), an oxygen concentration detection unit (5), and an online calibration unit (6); the filtration unit (1), cooling unit (2), gas-water separation unit (3), heating unit (4), and oxygen concentration detection unit (5) are connected in sequence through pipelines; the online calibration unit (6) includes multiple standard oxygen tanks (601), each of which stores oxygen of different concentrations; each of the standard oxygen tanks (601) is connected to the oxygen concentration detection unit (5).

2. The online oxygen concentration detection and analysis instrument for waste incinerator flue gas according to claim 1, characterized in that, It also includes an airway backflush unit (7), which includes an air compressor (701) and a backflush solenoid valve (702); the output end of the air compressor (701) is connected to the output end of the filter unit (1) via a pipeline; the backflush solenoid valve (702) is located on the corresponding pipeline.

3. The online oxygen concentration detection and analysis instrument for waste incinerator flue gas according to claim 1 or 2, characterized in that, The filtration unit (1) is a flue gas filter; the cooling unit (2) is a cooler; and the heating unit (4) is a heater.

4. The online oxygen concentration detection and analysis instrument for waste incinerator flue gas according to claim 1 or 2, characterized in that, The gas-water separation unit (3) includes a gas-water separation tank (301), a peristaltic pump (302), and a three-way valve (303); the peristaltic pump (302) is connected to the bottom of the gas-water separation tank (301) through a pipe, and the three-way valve (303) is located on the corresponding pipe.

5. The online oxygen concentration detection and analysis instrument for waste incinerator flue gas according to claim 1 or 2, characterized in that, The oxygen concentration detection unit (5) includes multiple oxygen concentration sensors (501) and multiple air pumps (502); each oxygen concentration sensor (501) corresponds to each air pump (502); each oxygen concentration sensor (501) is connected to the heating unit (4) via the corresponding air pump (502).

6. A waste incinerator, comprising a boiler (9), characterized in that, The boiler (9) is equipped with an online oxygen concentration detection and analysis instrument for waste incinerator flue gas as described in any one of claims 1-5.

7. The waste incinerator according to claim 6, characterized in that, The boiler (9) is equipped with multiple burners (14) on its furnace body. One end of each burner (14) is connected to a fuel valve (13), and the other end of each burner (14) is connected to the furnace of the boiler (9). The boiler (9) has a flue (10) at its tail end, and the heat exchanger is installed in the flue (10); An air valve (12) is installed at the air inlet of the burner (14). The air valve (12) is connected to the outlet of the heat exchanger via a hot air pipe. The inlet of the heat exchanger is connected to a blower (11) with an air intake via a cold air pipe. There is a bypass valve between the cold air pipe and the hot air pipe. The signal output terminal of the oxygen concentration detection unit (5) is connected to the acquisition signal input terminal of the controller (17). The control display terminal of the controller (17) is connected to the human-machine interface operation display (16). The output terminal of the controller (17) is connected to the control terminal of the speed regulator. The other end of the speed regulator is connected to the blower (11).

8. The waste incinerator according to claim 7, characterized in that, A temperature sensor is installed inside the boiler (9), and the temperature sensor is connected to the fuel valve (13).

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