CN216791943U

CN216791943U - Fixed pollution source waste gas density testing device

Info

Publication number: CN216791943U
Application number: CN202123234792.3U
Authority: CN
Inventors: 李丹; 李晓东; 陈磊; 阎禺; 杨钦
Original assignee: Shanxi Lidejia Detection Technology Co ltd
Current assignee: Shanxi Lidejia Detection Technology Co ltd
Priority date: 2021-12-22
Filing date: 2021-12-22
Publication date: 2022-06-21
Anticipated expiration: 2031-12-22

Abstract

The utility model relates to the field of fixed pollution source monitoring, in particular to a fixed pollution source waste gas density testing device; aiming at solving the problem of the on-site rapid measurement of the exhaust density in the current fixed pollution source monitoring; including setting up the hot type flue gas sampling pipe in the flue, the other end that adds hot type flue gas sampling pipe is connected with instrument method flue gas humidity measuring device, instrument method flue gas humidity measuring device still is connected with condensing equipment, desicator, CO through the pipeline in order₂、O₂The device comprises a CO volume percentage concentration measuring device, a rotor flow meter and a vacuum pump; instrument method flue gas humidity measuring device and CO₂、O₂Volume percent of COThe specific concentration measuring devices are also connected with a density calculating device together; the utility model scientifically designs the sample introduction step, accurately controls the temperature and humidity conditions measured by each factor, is a smoke density measuring device which integrates the advantages of science, accuracy, convenience, rapidness and the like, and makes up the market blank of direct measurement of smoke density in the fixed pollution source waste gas monitoring.

Description

Fixed pollution source waste gas density testing device

Technical Field

The utility model relates to the field of fixed pollution source monitoring, in particular to a fixed pollution source waste gas density testing device.

Background

Fixed pollution sources-herein, refer to pollution sources that exhaust gas generated from various production processes (e.g., fuel boilers, furnaces, etc.) or waste disposal processes (e.g., garbage incineration) through flues, chimneys, exhaust stacks, etc. into the air.

In fixed pollution source monitoring, exhaust emission and particulate matters are two main monitoring indexes and are basically important indexes which must be measured. As can be seen from equations (1) and (2), the measurement of both these criteria is dependent on the exhaust flow rate (V)_s) The latter (isokinetic sampling of particulate matter) also depends on the molecular weight M of the dry exhaust gas_sd. And it can be seen from equation (3) that the exhaust flow rate is closely related to the exhaust density.

Q_s＝3600·F·V_s (1)

Q_sExhaust flow m under operating conditions³/h；

F-monitoring area of section, m²；

V_s-monitoring the average flow velocity of the cross section, m/s;

Q_rsampling flow rate of particles at constant speed, L/min;

d, the diameter of the sampling nozzle is mm;

V_si-monitoring point air flow velocity, m/s;

B_aatmospheric pressure, P_a；

P_sStatic pressure of gas in the pipe, P_a；

t_s-gas temperature in the pipeline, ° c;

P_r-gas pressure before flowmeter, P_a；

t_r-gas temperature before flow meter, ° c;

M_sd-molecular weight of dry exhaust gas, kg/kmol;

X_sw-water content in exhaust gas volume percentage,%.

V_si-gas flow rate of wet exhaust at a certain point, m/s;

K_p-pitot tube correction factor;

P_di-a certain point exhaust dynamic pressure, Pa;

ρ_sdensity of the wet exhaust gas, kg/m³；

The test of exhaust gas density monitoring by an exhaust gas fixed source adopts the method of 'method for measuring particulate matters in exhaust gas of fixed pollution source and sampling gaseous pollutants' of '5.3.2 gas analyzer' of GB/T16157-1996 for CO and CO in exhaust gas₂、O₂And N₂Measuring the moisture content in the exhaust gas by adopting other methods (a fixed-point position electrolysis method, a resistance-capacitance method, a weight method or a condensation method), calculating the density of the wet exhaust gas in a standard state by a formula (4), and manually inputting the density into a sampling instrument. The analysis principle of the 's gas analyzer method is as follows: taking a certain amount of discharged gas (such as 100ml), absorbing each component of the discharged gas one by using different absorption liquids, and calculating the volume percentage of the component in the discharged gas according to the change of the volume of the discharged gas before and after absorption.

ρ_n＝[(M_CO2X_CO2+M_O2X_O2+M_COX_CO+M_N2X_N2)(1-X_sw)+M_H2OX_sw]/22.4 (4)

In the formula: rho_nDensity of the wet exhaust gas in the standard state, kg/m³；

M_CO2、M_O2、M_CO、M_N2、M_H2OMolecules of carbon dioxide, oxygen, carbon monoxide, nitrogen and water in the exhaust gas

Amounts, kg/kmol, of 44, 32, 28, 28, 18, respectively;

X_CO2、X_O2、X_CO、X_N2volume percent of oxygen, carbon monoxide, carbon dioxide, nitrogen in the dry exhaust gas,%;

X_swvolume percent of moisture content in exhaust gas,%.

ρ_s＝ρ_n*[273/(273+t_s)*(B_a+P_s)/101325] (5)

In the formula: rho_s___ Density of wet exhaust gas in flue under measured condition, kg/m³；

t_s___ temperature of exhaust gas, ° c;

P_s___ static pressure, Pa, of the exhaust gas.

The austenite gas analyzer is a combined glassware, and the analysis method is a solution absorption method. The most major problems with this device are: 1) the measuring device is not inconvenient to carry to the site and is easy to damage; 2) the solution preparation and carrying are inconvenient; 3) the measuring process is complicated, manual recording and calculation are needed, and the working efficiency is low.

In actual work, the index is not basically measured, and a set value of 1.34 in a fixed source exhaust gas sampling instrument is adopted, namely the moisture density value of air in a standard state. The method has little influence on the measurement results of the exhaust emission of the open type smoke dust collecting device and the machining type exhaust gas, but can generate great errors on the monitoring of chemical reactions such as combustion exhaust gas, chemical production exhaust gas and the like, seriously influences the accuracy of the monitoring result, and is a hard damage on the monitoring of the existing exhaust gas fixed source.

Disclosure of Invention

The utility model provides a device for testing the density of waste gas of a fixed pollution source, which aims to solve the problem of rapid field measurement of the density of the discharged gas in the conventional fixed pollution source monitoring.

In order to solve the technical problems, the technical scheme adopted by the utility model is as follows: fixed pollution source waste gas density testing arrangement is including setting up the heating type flue gas sampling pipe in the flue, and the other end that adds the heating type flue gas sampling pipe is connected with instrument method flue gas humidity measuring device, instrument method flue gas humidity measuring device still is connected with condensing equipment, desicator, CO in order through the pipeline₂、O₂The device comprises a CO volume percentage concentration measuring device, a rotor flow meter and a vacuum pump; instrument method flue gas humidity measuring device and CO₂、O₂The CO volume percentage concentration measuring device is also connected with a density calculating device, the instrument method flue gas humidity measuring device and the CO₂、O₂And the CO volume percentage concentration measuring device transmits the measured data to the density calculating device, and then the density calculating device calculates the data to obtain a density test result.

The working principle and the process are as follows: the flue gas enters the instrument method flue gas humidity measuring device 2 through the heating type flue gas sampling pipe 1 under the action of the vacuum pump 7 to obtain the volume percentage X of the moisture content in the exhaust gas_swThen the flue gas is condensed and dried and enters CO₂、O₂And CO is respectively measured by the CO volume percentage concentration measuring device 5₂Concentration X_CO2、O₂Concentration X_O2CO concentration X_COAnd calculating N₂Concentration X of_N2＝(1-X_CO2-X_O2-X_CO) Then X is added_sw、X_CO2、X_O2、X_CO、X_N2And the data are transmitted to a density calculating device 8, and the result is calculated according to the formula (4).

The design principle of the measuring device is based on that the volume percentage concentration of the measured gas component does not change along with the change of temperature and pressure under the gaseous condition.

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

the utility model utilizes and integrates the single-factor gas component measuring methods of moisture (humidity), carbon dioxide, oxygen, carbon monoxide and the like in the existing specification, has accurate results and can be relied on;

according to the requirements of the measuring method of each factor, the utility model scientifically designs the sample introduction step, accurately controls the temperature and humidity conditions measured by each factor, is a smoke density measuring device which integrates the advantages of science, accuracy, convenience, rapidness and the like, and makes up the market blank of direct measurement of smoke density in the fixed pollution source waste gas monitoring.

Drawings

FIG. 1 is a schematic structural diagram of a device for measuring the density of exhaust gas from a stationary pollution source according to the present invention.

Fig. 2 is a schematic diagram of the operation of the device of the present invention.

The figures are labeled as follows:

1-heating type flue gas sampling pipe, 2-instrument method flue gas humidity measuring device, 3-condensing device, 4-dryer, 5-CO₂、O₂The device comprises a CO volume percentage concentration measuring device, a 6-rotor flow meter, a 7-vacuum pump, an 8-density calculating device and a 9-flue.

Detailed Description

The present invention is further illustrated by the following specific examples.

Examples

As shown in figure 1, the device for testing the density of the waste gas of the fixed pollution source comprises a heating type smoke sampling pipe 1 arranged in a flue, the other end of the heating type smoke sampling pipe 1 is connected with an instrument method smoke humidity measuring device 2, and the instrument method smoke humidity measuring device 2 is further sequentially connected with a condensing device 3, a dryer 4, CO through pipelines₂、O₂A CO volume percentage concentration measuring device 5, a rotor flow meter 6 and a vacuum pump 7; instrument method flue gas humidity measuring device 2 and CO₂、O₂The CO volume percentage concentration measuring device 5 is also connected with a density calculating device 8, and the instrument method flue gas humidity measuring device 2 and the CO are connected with the density calculating device₂、O₂And the CO volume percentage concentration measuring device 5 transmits the measured data to the density calculating device 8, and then the density calculating device 8 calculates the data to obtain a density test result.

Further, the arrangement direction of the heating type flue gas sampling pipe 1 is perpendicular to the direction of flue gas flow. The sampling pipe is a heat-resistant corrosion-resistant stainless steel pipe, the length is more than or equal to 800mm, and the inner diameter is more than or equal to 6 mm; the heating and heat preservation functions are realized, and the integral temperature control is 130 +/-10 ℃; the most front end is provided with a dust filter.

Preferably, the instrument-method flue gas humidity measuring device 2 is a resistance-capacitance-method humidity measuring device, and the sensor is arranged behind a dust filtering device at the front end of the sampling pipe.

Preferably, the CO is₂、O₂The CO volume percentage concentration measuring device 5 consists of 3 independent measuring devices, wherein CO₂CO by infrared method, O₂An electrochemical method is adopted.

Preferably, the density calculation device 8 is a set of data receiving, storing, calculating and outputting devices.

The working principle is shown in figure 2, the flue gas enters the instrument method flue gas humidity measuring device 2 through the heating type flue gas sampling pipe 1 under the action of the vacuum pump 7, and the volume percentage X of the moisture content in the exhaust gas is obtained_swThen the flue gas is condensed and dried and enters CO₂、O₂And CO is respectively measured by the CO volume percentage concentration measuring device 5₂Concentration X_CO2、O₂Concentration X_O2CO concentration X_COAnd calculating N₂Concentration X of_N2＝(1-X_CO2-X_O2-X_CO) Then X is added_sw、X_CO2、X_O2、X_CO、X_N2And the data are transmitted to a density calculating device 8, and the result is calculated according to the formula (4). The rotor flow meter 6 is used for controlling the pumping flow at 1.0L/min.

Claims

1. Fixed pollution source waste gas density testing arrangement, its characterized in that: the device comprises a heating type flue gas sampling pipe (1) arranged in a flue, wherein the other end of the heating type flue gas sampling pipe (1) is connected with an instrument method flue gas humidity measuring device (2), and the instrument method flue gas humidity measuring device (2) is sequentially connected with a condensing device (3), a dryer (4) and CO through pipelines₂、O₂CO is concentrated by volume percentageThe device comprises a degree measuring device (5), a rotor flow meter (6) and a vacuum pump (7); instrument method flue gas humidity measuring device (2) and CO₂、O₂The CO volume percentage concentration measuring device (5) is also connected with a density calculating device (8) together, and the instrument method flue gas humidity measuring device (2) and the CO are₂、O₂And the CO volume percentage concentration measuring device (5) transmits the measured data to the density calculating device (8), and then the density calculating device (8) calculates the data to obtain a density test result.

2. The stationary pollution source exhaust gas density testing device according to claim 1, wherein: the arrangement direction of the heating type flue gas sampling pipe (1) is perpendicular to the direction of flue gas flow; the sampling pipe is a heat-resistant corrosion-resistant stainless steel pipe, the length is more than or equal to 800mm, and the inner diameter is more than or equal to 6 mm; the heating and heat preservation functions are realized, and the integral temperature control is 130 +/-10 ℃; the most front end is provided with a dust filter.

3. The stationary pollution source exhaust gas density testing device according to claim 1, wherein: the instrument method flue gas humidity measuring device (2) is a resistance-capacitance method humidity measuring device, and the sensor is arranged behind a dust filtering device at the front end of the sampling pipe.

4. The stationary pollution source exhaust gas density testing device according to claim 1, wherein: said CO₂、O₂The CO volume percentage concentration measuring device (5) consists of 3 independent measuring devices, wherein CO₂CO by infrared method, O₂An electrochemical method is adopted.

5. The stationary pollution source exhaust gas density testing device according to claim 1, wherein: the density calculating device (8) is a set of data receiving, storing, calculating and outputting devices.