In the copper smelting industry, energy cost is always the core issue of concern for enterprises. Fullcryo provides a complete set of oxygen-enriched natural gas combustion control solutions for a large copper smelting customer in Jiangxi Province, China, including the VPSA oxygen generation system, the intelligent combustion control system and the high-efficiency combustion equipments, which can effectively help the customer in copper smelting to realize the reduction of cost and increase efficiency.
The concept of oxygen-enriched combustion was first proposed by Homne and Steinburg in 1981, and verified by Argonne National Laboratory. Simply speaking, oxygen-enriched combustion refers to the use of oxygen-enriched air or pure oxygen with a higher concentration of oxygen than conventional air (21% oxygen) as the combustion gas rest, which is a highly efficient and energy-saving combustion technology. Compared with the traditional combustion method of using air (containing about 21% oxygen) as the oxidant, oxygen-enriched combustion can increase the oxygen content to 30% or even more than 90%, thus realizing higher flame temperatures and fuller fuel reaction, which in turn brings multiple benefits of fuel saving, emission reduction and thermal efficiency improvement.
In the copper smelting process, fuel cost occupies a high proportion. Especially in the context of adopting natural gas as a cleaner fuel instead of traditional coal, how to further improve the efficiency of natural gas utilization has become the focus of attention.
Oxyfuel combustion has the following main advantages:
With the “double carbon” goal and the promotion of green transformation, oxygen-enriched combustion can not only improve fuel utilization, but also effectively reduce the harmful degree of various emissions after combustion, for energy saving and emission reduction has a very good prospect for the application of this technology has been in the iron and steel, non-ferrous metallurgy, glass, chemical industry and other energy-intensive industries have been widely used, and has become a key factor in improving energy utilization, reducing the operation of the kiln, and improving the environmental protection index. It has become a key means to improve energy utilization and reduce operating costs.
To realize oxygen-enriched combustion, it is necessary to solve the problem of the source of oxygen. The traditional reliance on liquid oxygen transportation is not only costly and easy to lose, but also has the risk of unstable oxygen supply. Therefore, on-site oxygen generation system has become the preferred solution for modern industry.
Currently, the common methods of oxygen generation in the industrial field include deep cooling air separation method, variable pressure adsorption (PSA/VPSA) and membrane separation method. Among them, the deep cooling air separation method can obtain oxygen with purity of more than 99%, which is suitable for the scenario of extremely high requirements on oxygen purity, but its system is complex, large investment, high operational energy consumption, and is mainly used in large-scale iron and steel, petrochemical and other traditional industries. Membrane separation method utilizes the difference of permeation rate of different gas molecules in the membrane to separate oxygen, the equipment structure is compact, but the purity of the produced oxygen is lower (generally about 30%), more suitable for auxiliary occasions with lower requirements on oxygen concentration.
In contrast, variable pressure adsorption (PSA/VPSA) is becoming the mainstream choice for industrial oxygen enrichment applications by virtue of its advantages of high oxygen purity, low operating cost, simple equipment structure and strong adaptability.
The principle of variable pressure adsorption to produce oxygen is: using the difference in adsorption capacity of oxygen and nitrogen in the air on solid adsorbent (such as molecular sieve), the oxygen and nitrogen are separated from the air by alternately changing the pressure conditions. Among them, VPSA (Vacuum Pressure Swing Adsorption), as an upgraded form of Variable Pressure Adsorption, adsorbs at atmospheric or low pressure and desorbs under vacuum conditions, which makes the system consume less energy and produce more gas, and is more suitable for medium and large-scale continuous oxygen consumption scenarios.
The role of oxygen is crucial in the copper smelting process. In the modern copper smelting process represented by flash smelting, oxygen is widely used in oxygen-enriched smelting, high-temperature oxidation reaction and fuel combustion. By increasing the concentration of oxygen, the oxidation reaction of sulfur, iron and other impurities in the copper concentrate can be accelerated, and the reaction rate and furnace temperature can be significantly increased, thus reducing fuel consumption, shortening the smelting time, and improving the metal recovery rate and environmental emission level. Especially in the context of natural gas replacement of traditional coal-fired, oxygen and fuel synergistic regulation of oxygen-enriched combustion system, has become an important means of energy saving and emission reduction.
This application is just a microcosm of the wide application of oxygen in the metallurgical industry. Oxygen plays an irreplaceable role in many metallurgical segments such as iron and steel, non-ferrous metals, alloys, etc.
Converter steelmaking: oxygen high-speed blowing can quickly remove carbon, silicon, phosphorus and other impurities in the molten iron and improve the quality of steel.
Electric arc furnace steelmaking: oxygen-enriched combustion reduces power consumption and improves the furnace temperature.
Stainless steel smelting (AOD furnace): oxygen and argon cooperate to accurately control the carbon content and retain the alloying elements.
Non-ferrous metal Non-ferrous metal smelting (aluminum, nickel, zinc, etc.): oxygen is involved in high-temperature oxidation reaction to improve the reduction rate.
Metal heat treatment and reduction process: oxygen is used to regulate the atmosphere, which affects the material properties.
With the continuous promotion of the “double carbon” goal, oxygen is not only an indispensable reaction medium in the smelting process, but also a key energy factor to promote the development of green metallurgy.
Fullcryo delivered a complete oxygen-enriched combustion system solution for a large copper smelting company in Jiangxi, covering the whole process from oxygen preparation to combustion control, which helps the customer to achieve the goals of energy saving, consumption reduction and green smelting.
The core content of the project includes:
VPSA Oxygen Generation System: Adopting advanced variable pressure adsorption technology (VPSA), the system provides customers with stable, continuous industrial oxygen with purity up to 93%, which meets the demand for oxygen-enriched gas supply of the smelting process, and significantly reduces the cost of purchasing and transporting liquid oxygen.
Natural Gas-Oxygen Combustion Control System: Through the intelligent adjusting system, it realizes the accurate ratio of gas to oxygen and controls combustion conditions automatically, ensuring the flame stability and thermal stability, and ensuring the flame stability and thermal stability. Natural gas-oxygen combustion control system: through the intelligent adjustment system, the precise ratio of gas and oxygen is realized, and the combustion conditions are automatically controlled to ensure the optimization of flame stability and thermal efficiency.
Customized combustion equipment: taking into account the high-temperature characteristics of the copper smelting process and the structural features of the furnaces, the new burners and gas supply modules are specially designed to be high-temperature-resistant and low-emission to take into account safety and energy saving.
The system was put into operation at the beginning of 2023, and customer feedback shows that the natural gas unit consumption per ton of copper was successfully controlled at 30-35 Nm³, which is more than 20% lower than the original process, and the annual fuel cost savings amounted to more than one million yuan. In addition, the introduction of oxygen-enriched combustion makes the furnace temperature control more accurate, the metal reduction rate is significantly improved, the concentration of NOx and particulate matter in the flue gas emission is reduced, the environmental protection benefits are significant, and the overall production efficiency and green level are improved simultaneously.
During the implementation of the project, Fullcryo team participated in the whole process from design, civil engineering, installation to commissioning, to ensure that the project was put on line quickly, and the customer evaluated it as “mature technology with remarkable energy-saving effect”, and plans to expand the application of the program to other production lines.
Fullcryo has been focusing on on-site oxygen generation and oxygen-enriched combustion technology for a long time, with mature VPSA technology (to achieve continuous and stable output of 80%-94% purity of oxygen), combustion system integration capabilities and on-site engineering implementation experience, has provided customers with total solutions in many industries, such as iron and steel, non-ferrous metals, glass, environmental protection and so on. Total solution.
We not only provide equipment, but also provide one-stop service from design, manufacturing, installation, commissioning to later operation and maintenance, to ensure the stable operation of the system and maximize the economic benefits.
Compared with traditional liquid oxygen procurement, VPSA on-site oxygen production has the following significant advantages:
Produce as much as you need: supply oxygen on demand, reduce waste.
Fast system response: flexible startup and shutdown, stable operation.
Cost saving: avoid liquid oxygen transportation and evaporation loss, low energy consumption.
Compact and easy to install: modularized design, adaptable to different site requirements.
Fullcryo is committed to become a professional supplier of industrial gas solutions, creating a more energy-efficient, smarter and greener future for our customers.
