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Circular economy

Hoa Phat Steel applies circular economy for cost saving

22/09/2021

Hoa Phat Group has proactively promoted the circular economy model in many production and business activities, helping to save thousands of billions VND in production and business costs and increase the value of the production chain.
With the characteristics of multi-industry and multi-field industrial production, in which iron and steel production takes up a large amount of electricity, water, coal, etc.,Hoa Phat Group has applied the circular economy model to the production process in order to save energy, natural resources, and contribute to environmental protection.
In particular, the product of one factory is the input material of another factory in order to optimize the value-added chain of the metallurgical cycle. At the same time, the closure of the production chain also helps factories to thoroughly recover and effectively reuse waste gas, waste water, residual heat as well as solid waste after each production stage.
In the steelmaking stage, Hoa Phat Group uses Basic Oxygen Furnace (BOF) technology with 10% - 15% lower electricity consumption per ton of steel than Electric arc furnace (EAF) which is commonly used in Viet Nam. However, BOF technology generates a large amount of toxic, flammable CO.

The application of the circular economy model helps Hoa Phat Group save trillions VND in production and business costs as well as significantly increase the value of the steel production chain
To solve this problem, the production system has been improved by Hoa Phat engineers in order to thoroughly recover all CO2 and store it in a large capacity tank to reuse as fuel instead of using LPG or FO oil in other production stages such as calcining lime as a slag additive, producing pellets, etc.
In addition, the superheated steam with a temperature of over 150oC - 200oC and a pressure of 6.5 bar generated from the steelmaking and steel rolling process is utilized, leading back to serve other production stages such as sintering and pellet production. At the same time, the steam pressure is reduced to 4 bar to serve the kitchens of the complexes, replacing the use of gas. This superheated steam solution helps to save more than 200 million VND/month in the cost of using gas in the kitchens.
Another improvement is that most of the billet heating furnaces are usually burned with FO oil, while the Hai Duong Iron and Steel Complex uses a system of 10 coal gasifiers to produce CO from anthracite coal as fuel for heating furnaces of rolling mills, saving up to 50% of fuel costs for the steel rolling process. The amount of iron-containing dust recovered in the process of iron and steel making and steel rolling is also reused in the production stages; At the same time, helping to increase the life of the production line.
The coking is also selected by Hoa Phat Group with advanced N2 gas dry coking technology instead of the traditional coal pyrolysis technology. N2 dry coking technology helps to reduce the emission of by-products such as coke oil, light oil, tar, etc., which heavily pollute the air and water sources.
This advanced coke stamping technology also allows the recovery of excess heat to produce electricity. Hai Duong Iron and Steel Complex has put into operation 4 residual heat generating sets with a total design capacity of 60 MW, providing about 1/3 of the electricity consumed by the whole Complex. If calculated according to the current average industrial electricity price, the electricity cost savings from this solution is up to 40.3 billion VND/month.
In Dung Quat Iron and Steel Complex, the cost savings thanks to the above solutions are even 2.5 times higher than in Hai Duong thanks to the larger production scale, the optimal system. In 2020, this complex uses nearly 1.6 billion KWh of electricity, of which 1.2 billion KWh can be produced by the complex itself (reaching 80% autonomy). Comparatively, the cost savings thanks to the solution of heat and exhaust gas recovery at Hoa Phat's steel complexes since 2021 is in the range of VND 4,000 billion.
Ha Tran