Steel industry waste: Once it polluted environment, now fetches forex

Infograph: TBS

The wastes or by-products emanating from the steel industry in the country which once led to severe environmental pollution are now being transformed into valuable treasures, becoming a source of significant amounts of foreign exchange to boost the local economy.

The steel industry has three distinct processes – steel scrap melting, cold rolling, and steel re-rolling – each generating specific waste products: zinc ash, iron oxide, and mill scale respectively.

The collection, reprocessing and export of these wastes have now created employment opportunities for thousands as well as contributed to mitigating environmental pollution.

These waste products are now being exported to countries such as China, Malaysia, Korea, Vietnam, Thailand and the Netherlands.

According to the latest data of the Export Promotion Bureau (EPB), in the first five months of the current fiscal year (July-November), the export of these three types of wastes fetched $18.77 million for the country.

Mill scale

Mill scale is a residue that comes off iron during steel re-rolling to make mild steel rods, containing 58%-70% iron that is recycled to obtain iron ore.

The export of this waste, mill scale, from over 400 steel re-rolling mills in the country started in 2007.

Previously, industrialists had to find spaces to dump the black-coloured solid waste, with 55%-70% ferrous material, causing severe soil and air pollution.

As the waste became valuable, exporters started buying mill scales for Tk4,000-8,000 per tonne and exporting them, mainly to China, for $70-120 per tonne.

Mohammad Mohiuddin, a pioneer in mill scale export, said, "Initially, three to four exporters were involved, but with growing international demand, over 30 exporters came into the business."

However, only four of them sustained their involvement.

Besides, with a decline in rolling mills' production, the by-product's output decreased in the last two years.

In FY22, mill scales worth $22.57 million were exported. The next year, exports nearly halved to $14.99 million.

In the first five months of FY24, mill scales worth $8.22 million were exported to Bhutan, Malaysia and Vietnam.

Zinc ash

BSRM initiated the export of zinc ash in 2013. As a major steel producer with two scrap steel melting units in Chattogram's Nasirabad area, it used to emit significant black smoke during scrap melting to produce billets, posing environmental and health risks.

To tackle the problem, an air pollution control technology from Japan was installed in 2010, which captures and cools the smoke into ashes. The challenge of environmentally friendly disposal led to lab tests revealing 50%-70% zinc content in the ashes.

In 2013, BSRM successfully exported the first shipment, prompting other local exporters to follow suit.

Tapan Datta, deputy managing director of BSRM, said, "In 2013, we got a breakthrough and first exported the zinc ashes to a South Korean company through a Thai trader.

"Later, in 2018, we took up the challenge and started exporting directly to China, South Korea, Malaysia and India. We came to know that there were industries in different countries that refine the zinc ashes and produce zinc, which is used in making colours and printing cartridges."

According to EPB data, zinc ash exports amounted to $5.29 million in FY20, rising to $14.65 million the next fiscal year. Exports increased In FY22 and FY23 to $22.55 million and $23.16 million, respectively.

In the first five months of the current fiscal year, zinc ash worth $10.39 million has been exported to China, India, Korea, the Netherlands and Thailand.

Iron oxide

Iron oxide powder, coming from large flat steel factories, is a by-product of the early stages of corrugated steel production from crude steel processing. Processing this red-coloured powder produces iron ore for various applications in metallurgy.

A decade ago, the waste generated from cold rolling mills had no value, and industrialists were relieved if someone would dispose of it. Over time, a shift occurred as individuals began purchasing this waste, leading to the initiation of exports.

For several years now, entrepreneurs in the steel industry have been earning revenue in dollars through the direct export of this waste. Flat steel units of PHP, KDS, AKS, Karnaphuli in Chattogram and a few others from Dhaka are now exporting this waste.

According to EPB data, in FY22, income from its exports earned $210,000. In FY23, exports jumped to $280,442. 

In the first five months of the current fiscal year, export stands at $161,797. The product has found its way to international markets, including China, Korea, and Malaysia.