Methods for treating exhaust gases from boiler combustion can vary depending on the specific exhaust gas composition and emission requirements. Here are some common waste gas treatment methods:

Wet exhaust gas scrubbing: For waste gas containing harmful gases such as SO2, wet exhaust gas scrubbing is a common method. By passing the exhaust gas into the scrubber, water or other liquids are used to absorb and dissolve pollutants in the exhaust gas to achieve the purpose of purifying the exhaust gas.

Dry exhaust scrubbers: Dry exhaust scrubbers use solid absorbents or filter materials to capture and remove contaminants from exhaust gases. This is effective at removing particulate matter and some gaseous pollutants such as NOx.

SCR (Selective Catalytic Reduction): For the control of nitrogen oxides (NOx), the SCR system is a common technology. The system uses a catalyst to help convert NOx into nitrogen and water vapor, often requiring the addition of urea or ammonia as a reducing agent.

Flue gas desulfurization: When the exhaust gas contains sulfur dioxide (SO2), flue gas desulfurization technology can be used to convert SO2 into gypsum or other stable substances by adding limestone or other desulfurizers during the combustion process.

Exhaust gas heat exchange: Through exhaust gas heat exchange, the heat energy in the exhaust gas can be recovered and the energy utilization efficiency of the boiler system can be improved. This is beneficial both for saving energy and reducing your carbon footprint.

Improved combustion process: Optimizing the combustion process of the boiler and using advanced combustion technology and control systems can reduce the generation of some pollutants in the exhaust gas.

The choice of these methods depends on factors such as the type of boiler, fuel used, exhaust emission standards and economic feasibility. Generally, waste gas treatment is a comprehensive consideration of technical, economic and environmental aspects. When conducting waste gas treatment, relevant regulations and standards should be followed to ensure that emissions comply with environmental protection requirements.

What exhaust gases are generally produced by boiler combustion?

Boiler combustion processes usually produce a variety of exhaust gases, the composition of which depends on the type of fuel used and the combustion technology. The following are some common exhaust gas components produced by boiler combustion:

1. Carbon dioxide (CO2): One of the main products of the combustion process, it is usually a relatively harmless gas, but its increase in the atmosphere has been linked to climate change.

2. Nitrogen oxides (NOx): Including nitric oxide (NO) and nitrogen dioxide (NO2), which are produced by high-temperature combustion of nitrogen in the air. NOx is one of the main sources of air pollution and is harmful to the environment and human health.

3. Sulfur Dioxide (SO2): Sulfur dioxide is produced when burning fuel contains sulfur. SO2 is a harmful gas that can cause acid rain and air pollution.

4. Particulate Matter: Includes visible and microscopic particles, which are small particles produced during combustion and may contain carbon, metals, sulfur and other substances. Particulate matter has potential impacts on air quality and human health.

5. Carbon monoxide (CO): A product of incomplete combustion, it is toxic and harmful to human health. High concentrations of carbon monoxide can cause poisoning.

The principle of using wet scrubber to treat boiler exhaust gas

Wet exhaust gas scrubber is a device used to treat exhaust gas containing gaseous pollutants. It mainly purifies the exhaust gas by contacting the exhaust gas with liquid so that the pollutants in the gas are absorbed, dissolved or transformed. The following are the basic principles of wet exhaust gas scrubbers for treating boiler exhaust gas:

Inlet air treatment: The boiler exhaust gas first enters the air inlet of the wet exhaust gas scrubber. These exhaust gases usually contain various pollutants, such as SO2, NOx, particulate matter, etc.

Liquid Absorbent: In a wet exhaust scrubber, the exhaust gas comes into contact with a liquid, usually water or other specialized absorbent. The choice of this liquid absorbent depends on the type and concentration of pollutants in the exhaust gas.

Gas-liquid contact: The exhaust gas comes into contact with the liquid in the scrubber. During this process, contaminants in the gas are transferred into the liquid. Chemical reactions, absorption and dissolution are common gas-liquid interactions, and different contaminants may require different treatments.

Physical separation: The treated waste gas and liquid are separated through a physical separation device to ensure that there is almost no residual liquid in the washed gas. This can be achieved by providing packing, trays or other separation structures.

Emissions: The gas treated by the wet exhaust gas scrubber has greatly reduced the concentration of pollutants. The scrubbed gas can be further discharged into the atmosphere through the chimney, and its pollutant concentration has complied with relevant emission standards and regulations.

Wet exhaust gas scrubber is suitable for treating exhaust gas containing SO2, NOx, HCl, HF and other gases. Different types of wet exhaust gas scrubbers include spray towers, flushing towers and absorption towers. Their working principles and structures will be different, but the basic gas-liquid contact and physical separation principles are the same.