Blast furnace gas and converter gas are the main secondary energy sources for long-process iron and steel enterprises. The CO and CO₂ contained in blast furnace gas account for about 50% of the total volume, and the CO and CO in converter gas account for about 70% of the total volume. Improving the utilization efficiency of CO in coal gas and capturing CO₂ is one of the important ways to reduce carbon emissions in iron and steel enterprises.
The CO in the gas is enriched and injected back into the blast furnace, thereby saving the amount of coke and coal in the blast furnace smelting process, which is the most efficient way to use CO in the gas and the most suitable for steel enterprises.
The CO₂ in the gas is captured by means of low power consumption and low cost for carbon sequestration, oil displacement, steel slag mineralization, chemical synthesis, etc., which can help steel enterprises to perfectly realize the last "kilometer" of carbon reduction ".
For regions and enterprises with high calorific value gas demand and high natural gas purchase price, by enriching CO in blast furnace gas, 1800kcal ~ 2400kcal high calorific value gas can be obtained to replace natural gas, which not only saves high natural gas purchase costs, but also reduces the total carbon emissions of steel enterprises.
Technical features
High economy of CO enrichment
The separation of CO and N₂ can be achieved economically in a high N₂ atmosphere, with controllable costs. This technology won the "second prize of national technological invention" and is still the world's exclusive technology.
Stable operation of the device
The gas composition in the steel gas is fully studied, and the intensive, efficient and low-cost impurity treatment process is used to ensure the long-term and stable operation of the whole CO enrichment device.
CO₂ Removal and Capture Integration
The removal of CO₂ from steel gas can be integrated with CO₂ capture to provide a high-quality gas source with high CO₂ content for carbon capture, making it easy to achieve low-cost, low-energy CO₂ capture.
CO₂ capture low cost
Using the combined process of pressure swing adsorption combined with liquefied cold box, the cost of tons of CO₂ capture is controlled below 300 yuan, and the cost is lower when coupling steel gas CO enrichment technology.
Low energy consumption
Efficient use of the energy conversion advantages of the combined process to control the total energy consumption of tons of CO₂ capture below 2GJ. When the CO enrichment technology of steel gas is coupled, the energy consumption is lower.
Increase calorific value of gas
After carbon capture from steel gas, the ineffective components of gas can be greatly reduced, the proportion of effective components increases accordingly, and the calorific value of gas can be improved.
Application areas
Iron and steel enterprises
For iron and steel enterprises that need to carry out carbon capture and reduce a certain proportion of carbon emissions in stages, the blast furnace gas produced by the traditional blast furnace is returned to the blast furnace for carbon capture and CO enrichment, which is one of the more realistic and easy paths at this stage.
For the need for high calorific value (1800kcal ~ 2400kcal) gas, and the gas to achieve "zero" release of iron and steel enterprises, choose to part of the blast furnace gas for calorific value, can make full use of the existing gas, improve the efficiency of gas utilization and save the cost of purchasing natural gas.
