HBI, one of the best alternative of scrap among the steelmakers

With the rise of technology, industries have been impacted in one way or another; in the Iron and steel industry, though some factories still insist on their old and costly methods, others have changed to more eco-friendly and cost-effective ways such as switching from induction furnace to Electric arc furnace and using supplements of scrap such as HBI, DRI and CBC-DRI as the raw material.

In today's article, we will be talking about HBI, one of the most famous alternatives of scrap, which has become very noticeable among the steel makers in India, China, Pakistan and Bangladesh.

What is Hot Briquetted Iron?

Hot Briquetted Iron (HBI)?is a product produced by the hot sponge iron briquetting (HDRI) process at?temperatures above 650 ° C. This type of briquette is the best-known product for easy and safe transportation of sponge iron, worldwide.

Iron and steel industry are one of the industries that utilize briquetting technology, such as coal briquetting, coke briquetting, and sponge iron briquetting, widely.

Sponge Iron briquette is a product used in many steel plants worldwide. The Briquetting Process, depending on the temperature of the inputted sponge iron to the briquetting machine, is divided into two groups: hot and cold briquetting.

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HBI Specifications:

Among the hot briquetting properties of sponge iron that facilitate its transportation can be attributed to its low specific surface area, high mechanical strength and density, and optimum oxidation resistance.

HBI blocks the pores of DRI, decreases the accessible level, increases the density and upgrades thermal conductivity. And all of these, results in lowering the reactivity. Therefore, it is unexpected for HBI to be overheating. This feature results in easier and safer handling, storage and transportation compared to DRI.

Advantages of using HBI as a substitution of?Scrap

We can list many advantages for using?HBI as a substitution of Scrap, inorder to keep the article short and useful we have listed some of the main important reasons:

• The?lower price?of HBI than scrap or raw iron
• Better charge?of HBI
• Easier loading?due to the compression of HBI compare to the Scrap
• Reduction of?energy consumption?per time unit when using briquettes instead of scrap
• Easier transportation?and movement
• Resistance to the weather?conditions
• Having?density, more than sponge iron for two times.
• Having very?few remaining elements?in the melt
• Reduction?of the number of?charges?to the furnace
• Possibility of?ceaseless charge?to the furnace
• Possibility of?controlling nitrogen?in steel
• Creating?stability?in steel melting
• Having?specific?chemical and physical analysis

How to use HBI?

Using of HBI can be based on up to 30% replacement of scrap (15% light scrap and 15% heavy Scrap) by basket charge and more than that, up to 60% by continuous charge (total 90%). In fact, only up to 30% of the charge of HBI can be carried out by the basket for the following reasons:

• Preventing?HBI?agglomerating?at the bottom of the furnace
• Avoiding mixing?HBI and lubricants at the bottom of the furnace
• The?ability to mix?HBI and scrap in the charge basket of materials to the furnace

On a whole, to simply explain,?production of HBI consists of the following steps:

1. Iron pellet get fed into the reactor
2. Natural gas converted into a reduction gas and after that, injected.
3. Reduction gas will circulate in a closed system and get recycled

Shahram Mahyari