Application of oxy fuel combustion system in industrial furnaces

Application of oxy fuel combustion system in industrial furnaces

Application of oxy fuel combustion system in industrial furnaces

In the field of industrial production, the innovation of combustion technology is of vital importance to improving energy efficiency, reducing pollutant emissions and improving product quality.

As an emerging and efficient combustion technology, Oxy fuel combustion system (OCS)  is gradually gaining widespread attention and application in various industries.

This report aims to comprehensively introduce the principles, composition, advantages, application fields and development trends of oxy fuel combustion system, and provide reference for relevant enterprises and researchers.

1. System Principle

The Oxy-fuel combustion is the process of burning a fuel using pure oxygen, or a mixture of oxygen and recirculated flue gas, instead of air.

Since the nitrogen component of air is not heated, fuel consumption is reduced, and higher flame temperatures are possible. 

The oxy fuel combustion system(OCS) abandons the practice of using air as a combustion medium in traditional combustion methods, and instead uses extremely pure oxygen (usually with a purity of more than 90%) mixed with fuel for combustion.

The oxygen content in the air is only about 21%, and most of the rest is inert gases such as nitrogen.

In the traditional combustion process, a large amount of nitrogen will be heated and discharged with the flue gas, taking away a large amount of heat, resulting in low energy utilization.

In the oxy fuel combustion system, due to the lack of nitrogen dilution, the oxygen concentration is significantly increased, allowing the fuel to burn more fully and faster.

This not only greatly increases the combustion temperature, but also reduces the volume of the combustion products, thereby reducing the heat loss of the exhaust gas and improving the efficiency of energy utilization.

At the same time, the flue gas produced by oxy fuel combustion system has relatively simple components, mainly carbon dioxide and water vapor, which is conducive to the treatment of combustion products and the control of pollutants.

2. System composition

2.1 Oxygen supply unit: responsible for providing high-purity oxygen.

This usually includes air separation equipment, such as cryogenic air separation unit or pressure swing adsorption oxygen production equipment.

Cryogenic air separation unit can produce high-purity, large-scale oxygen, but the equipment investment is large and the operating cost is relatively high;

Pressure swing adsorption oxygen production equipment has the advantages of simple equipment, fast start-up, and small footprint, and is suitable for small and medium-sized oxygen needs.

2.2  Fuel supply unit: According to different application scenarios and requirements, a variety of fuels can be supplied, such as natural gas, liquefied petroleum gas, heavy oil, coal powder, etc.

The fuel supply unit needs to accurately control the flow and pressure of the fuel to ensure the best mixing ratio with oxygen.

2.3.Burner: It is the core component of the pure oxygen combustion system.

Its design and performance directly affect the combustion effect.

The pure oxygen burner needs to have good mixing performance to ensure that oxygen and fuel can be mixed quickly and evenly to achieve stable and efficient combustion.

At the same time, the burner must also have high temperature resistance and corrosion resistance to adapt to the high temperature and strong oxidation environment of pure oxygen combustion.

2.4 Control system: monitors and controls the entire pure oxygen combustion system in real time.

Sensors are used to collect parameters such as the flow rate, pressure, and temperature of oxygen and fuel, as well as information such as the flame temperature and flue gas composition during the combustion process.

The control system automatically adjusts the supply ratio of oxygen and fuel according to preset parameters and algorithms to ensure the stability and safety of the combustion process.

In addition, the control system also has fault alarm and safety protection functions.

Once an abnormal situation occurs in the system, timely measures can be taken to avoid accidents.

3 System Advantages

3.1 Improve energy efficiency:

Due to the elimination of the dilution and heat absorption of nitrogen, the combustion temperature of the oxy fuel combustion system (OCS) is higher, the heat is concentrated, and the chemical energy of the fuel can be more effectively converted into thermal energy, thereby improving energy efficiency and reducing energy consumption.

Compared with traditional combustion systems, the oxy fuel combustion system(OCS)  can save 15% – 30% of energy.

3.2 Reduce pollutant emissions:

The amount of flue gas produced by oxy fuel combustion system (OCS) is greatly reduced, and the flue gas composition is simple, which is conducive to the centralized treatment of pollutants.

At the same time, since the combustion temperature is easier to control, it can effectively reduce the generation of nitrogen oxides (NOx) and reduce pollution to the environment.

In addition, the concentration of carbon dioxide produced by pure oxygen combustion is high, which is easy to capture and utilize, meeting the requirements of sustainable development.

3.3 Improve product quality:

High temperature and stable combustion environment can help improve the heating quality and uniformity of products and reduce the defective rate of products.

In industries such as glass and metallurgy, the oxy fuel combustion system (OCS) can improve the purity and performance of products and enhance the market competitiveness of products.

3.4 Reduce equipment investment and floor space:

Since the flue gas volume of the pure oxygen combustion system is reduced, the scale of the corresponding flue gas treatment equipment (such as waste heat recovery equipment, desulfurization and denitrification equipment, etc.) can be reduced, thereby reducing equipment investment and floor space.

4. Application areas

4. 1. Glass industry:

In the glass melting process, the oxygen fuel combustion system (OCS) can increase the melting temperature, accelerate the melting and clarification process of glass, reduce bubbles and impurities in the glass, and improve the quality and output of glass.

At the same time, it can also reduce fuel consumption and pollutant emissions and improve the production environment.

4.2 Metallurgical industry:

In the smelting process of steel, nonferrous metals, etc., the oxy fuel combustion system (OCS) can increase the furnace temperature, speed up the smelting speed, reduce energy consumption, and improve the recovery rate and quality of metals.

In addition, the high temperature generated by pure oxygen fuel combustion can also be used for heating and heat treatment of metals to improve the properties of metals.

4.3 Chemical Industry:

In chemical production, many reactions need to be carried out in a high-temperature, high-purity environment.

The oxy fuel combustion system (OCS) can provide a high-temperature heat source that meets these reaction requirements, while reducing the introduction of impurities during the reaction process and improving the selectivity and yield of the reaction.

4.4 Ceramic industry:

During the ceramic firing process, the oxy fuel combustion system (OCS) can improve the temperature uniformity of the kiln, make the firing of ceramic products more uniform, reduce product deformation and cracking, and improve product quality and yield rate.

5. Development Trends

5.1. Technological innovation:

With the continuous advancement of science and technology, the technology of oxy fuel combustion system (OCS) is also constantly innovating and improving.

In the future, we will further develop efficient and energy-saving oxygen production technologies to reduce the production cost of oxygen; at the same time, we will optimize the design of burners, improve combustion efficiency and stability, and reduce nitrogen oxide emissions.

5. 2. Intelligent control:

With the help of technologies such as the Internet of Things, big data, and artificial intelligence, the oxygen fuel combustion system can be intelligently controlled.

By real-time monitoring and analysis of various parameters in the combustion process, the system’s operating status can be automatically adjusted to achieve the best combustion effect and improve the reliability and safety of the system.

5.3 Integration with other technologies:

The oxy fuel combustion system (OCS) will be deeply integrated with technologies such as residual heat recovery, carbon dioxide capture and utilization, to achieve cascade utilization of energy and zero emissions of pollutants, and further improve the overall benefits of the system.

5.4 Expansion of application areas:

 In addition to existing application areas, the oxy fuel combustion system (OCS) will also be more widely used in new energy, environmental protection and other fields, providing new technical means to solve energy and environmental problems.

6 Summary

As an advanced combustion technology, the oxygen fuel combustion system (OCS) has many advantages such as high energy utilization efficiency, low pollutant emissions, and good product quality.

It has broad application prospects in the field of industrial production.

With the continuous innovation and development of technology, the oxygen fuel combustion system (OCS) will be promoted and applied in more industries, making important contributions to promoting the green and sustainable development of industry.

However, the oxygen fuel combustion system (OCS) also faces some challenges in the process of promotion and application, such as high oxygen cost and greater safety risks.

Therefore, it is necessary to further strengthen technology research and development and innovation, reduce system costs, and improve system safety and reliability to promote the widespread application of pure oxygen combustion system.

References

1. Heat Treatment of Metals 富氧(纯氧)燃烧器的研究现状及发展趋势 

2.https://en.wikipedia.org/wiki/Oxy-fuel_combustion_process

March 22, 2025