The efficient operation of power plants today largely depends on accurate and reproducible measurements of the primary and secondary airflow entering the coal mill, flue gas recirculation flow rate, superheated airflow, and airflow towards various burners and other areas. It is crucial to choose a suitable flow meter for measuring the emission flow rate of flue gas or flue gas. This type of measurement is crucial for quantifying emissions through environmental reporting using Continuous Emission Monitoring Systems (CEMS) for pollution control by government agencies.

1. Components of flue gas combustion

Flue gas is a gas emitted during combustion due to the stoichiometric heating of fuel (liquid or solid or gas) and air in boilers and process furnaces.

The smoke generated by combustion mainly includes:

Nitrogen (N 2)

Carbon monoxide (CO)

Carbon dioxide (CO2)

Trace sulfur dioxide (SO2)

Nitrogen oxides (NO, NO2)

Suspended particulate matter (SPM)

water content

Flue gas is generated in thermal power plants, steel and foundry plants, cement production plants, fertilizer production and processing plants, as well as many other industrial, commercial, and other facilities.

Why is smoke flow measurement so important?

       Most of the emitted smoke contains air pollutants that are harmful to human health. CEMS requires government regulatory authorities to provide environmental pollution control reports. It is important to measure the composition, concentration, and mass flow rate of pollutants in order to determine the total emissions in the environment.

Smoke flow measurement is applicable for:

Optimizing the performance of electrostatic precipitators (ESP) by maintaining design parameters such as specific collection area, gas velocity, and processing time in controlled ESP;

Early warning of preheater condenser failure;

Assist in regulating harmful pollutants and controlling dust emissions;

Useful information on optimizing quality balance;

Easy to operate design; Helps with energy conservation;

Predictive and preventive measures for optimizing process efficiency and reducing harmful environmental emissions.

3 Process conditions for flue gas

         The process engineer designed the lowest possible environmental heat loss to improve the thermal efficiency of the power plant. The optimized flue gas process conditions usually have the following process parameters, such as:Composition, where the smoke has a moderate amount of dust/Fly ash particles, such as in coal-fired or steam power plants or processes;The process temperature is one hundred and thirty to 180⁰C；Processing speed: It is recommended to be around per second12- 20rice (m/s)；

Where should the smoke flow be monitored?

       To achieve optimal efficiency, smoke can be monitored for laboratory analysis near the sampling point or chimney; Wet flue gas desulfurization system in thermal power plants FGD/dry process FGD）Entrance; In the process stacks and ventilation systems of chemical production, fertilizers, and steel plants.

5. Key points for smoke flow monitoring technology and selection

 The following are important factors to consider and evaluate when selecting the best flow measurement solution through comparative techniques:

Size of air ducts or pipes;

Insulation thickness, if any;

Process conditions such as flow rate, pressure, temperature, density, viscosity, dirt, and moisture;

Installation conditions, such as horizontal, vertical, and available straight line length, time and effort, etc;

Accuracy and repeatability are required;

The required process adjustment ratio;

Budget price;

        Based on the above factors,MEZOLENLaunchedMT1600GBThe series of flue gas ultrasonic flow meters can accurately meet the above measurement requirements.MT1600GBThe universal gas insertion ultrasonic flowmeter is a flowmeter specially designed for low-pressure large-diameter gas flow measurement, with stable and reliable measurement and a wide range of measurement. The sensor has a built-in temperature sensor, and the transmitter can be connected to a pressure transmitter signal to perform temperature and pressure compensation calculations on the flow inside the pipeline.This product complies with JJG1030-2007 Standard, explosion-proof design, widely used in torch gas, steelmaking, and coal for large petrochemical plants.Flow measurement of coal gas, power plant flue gas, etc. in coking units. The product configuration is flexible, with optional mono to quad channel configurations. The transmitter and sensor are installed separately, with low starting flow rate and wide range. It is an ideal large-diameter gas flow measurement flowmeter.

 Advantages:

1. Derive volumetric flow rate through ultrasonic beam transmission time measurement;

2. Used for pipelines with a diameter of up to 10 meters;

3. Suitable for temperatures up to 450 ⁰ C;

4. Install horizontally or vertically;

5. Wide measurement range, with a range ratio of up to 3000:1;

6. Overall explosion-proof design, explosion-proof mark: Exd IICT6;

7. If the initial flow rate is low and the flow velocity is greater than 0.03m/s, stable measurement can be achieved;

8. The transmitter and sensor are installed separately, and the longest extension cable can reach 50 meters;

9. No movable parts, maintenance free, capable of bidirectional measurement;

10. The all titanium alloy shell sensor has good protection performance, strong anti-interference ability, and can measure moisture;

11. Patent technology sensor layout, single hole vertical installation and installation, simple on-site construction;

12. Multiple channel configurations to meet different precision requirements;

13. Built in temperature sensor, can be connected to an external pressure transmitter signal for real-time temperature and pressure compensation calculation;

14. LCD display can display the normal and faulty working status of the instrument, and can display instantaneous flow rate;

15. Accumulated flow rate, flow velocity, sound velocity, signal strength, signal quality, etc;

16. It can store various parameters of the instrument configuration, including running time, cumulative quantity (positive cumulative, negative cumulative, and algebraic cumulative flow), historical error information, etc. Daily historical data is 1 year, and monthly historical data is 10 years.