Copper slag, known in Vietnam as ‘nix grains,’ is a by-product of copper extraction by smelting and is mainly used to clean and shape the surface of metal, stone, concrete and other materials.
Hyundai Vinashin Shipyard Company (HVS), located in the Khanh Hoa-based Van Phong Economic Zone, some 80km from the popular beach of Nha Trang, has imported a huge number of this material to clean its vessels since May 1999.
The copper slag waste dumped by HVS was previously supposed to be treated by a plant developed by the Hanoi Minerals – Metallurgy inside the same economic zone.
However, the VND1.49 trillion (US$74.6 million) waste treatment plant, licensed in December 2009, failed to get work started and lost it license in January 2013.
The cancelation of the Hanoi Minerals – Metallurgy project has resulted in a huge pile of more than one million metric tons of the copper slag waste at Van Phong Economic Zone over the last four years.
The toxic dust from the ‘waste mountain’ has since affected thousands of residents of two villages located near the plant.
It was not until July 2017 that HVS revealed that it has found a solution for the problem: transporting the waste to other localities where they would be used as auxiliary materials for cement production.
According to the Khanh Hoa administration, HVS has closed contract to supply its nix waste to three companies outside the province, namely Hanoi-based Mascon, Dong Do Co. in the northern province of Ninh Binh and Holcim Vietnam in Ho Chi Minh City.
Of the three companies, only Holcim Vietnam directly uses the waste for its production. Mascon and Dong Do Co. would resell the materials to other cement-making plants, including the Hoang Phat – Vissai in Ninh Binh and Cosevo Song Gianh in the north-central province of Quang Binh.
As per the contract, HVS will give a financial support of US$5 per ton, covering both transportation and treatment costs, to the waste recipients.
Thanks to these agreements, HVS has managed to clear nearly 48 percent of the ‘waste pile’ at Van Phong, with some 10,000 metric tons taken out of Khanh Hoa on a monthly basis, according to the company’s own report.
The shipbuilder said it is still looking for new partners capable of receiving and treating the copper slag waste to speed up the process of clearing the nix waste mountain.
Khanh Hoa authorities have confirmed that HVS has been approved to carry out its waste clearing solution, and the transportation of the waste out of the province is under strict oversight.
The General Department of Environment has also said in a statement that it supports the HVS solution, but requesting that the shipbuilder “be legally responsible for the waste treatment from start to finish.”
This means HVS has to ensure that its partners are capable of properly treating the copper slag waste taken from Khanh Hoa as the shipbuilding company will be held accountable for any wrongdoings, according to the general department.