Is hot dip galvanizing an environmentally sustainable surface treatment method?
Hot dip galvanizing – dipping steel in molten zinc – is probably the most environmentally friendly process available to counter corrosion. The cost of corrosion in the Nordic countries is estimated at around 4% of the countries’ gross domestic product. Thus, there are major economic benefits in the corrosion protection of buildings and structures, while effective corrosion protection is also a powerful way to reduce the carbon dioxide load.
Can hot-dip galvanized steel be reused?
Many hot-dip galvanized products can be re-galvanized when the original zinc layer has corroded away. In many countries, for example, old road railings are taken down and sent on re-galvanizing in connection with the regular maintenance work carried out on the roads.
Can hot-dip galvanized steel be recycled?
Hot-dip galvanized steel can easily be recycled together with other scrap when melted in an arc furnace. The zinc evaporates early in the process and is collected in the arc furnace filter, from which it can then be extracted and reused in zinc production.
Is it possible to recover zinc?
Zinc is a naturally recyclable non-ferrous metal and can be recycled endlessly many times without losing its physical or chemical properties. Currently, approximately 70% of the zinc comes from primary sources (containing 10-15% recycled zinc) while 30% is entirely based on recycled zinc. These 30% correspond to 80% of the total amount of zinc available for recycling. The recycling rate continues to increase as the technology develops.
Will the zinc run out?
Zinc is the 27th most common substance in the earth’s crust. The world is naturally rich in zinc. Zinc reserves – like all natural resources – are not a fixed amount stored in nature. The reserves depend on geological factors and the interaction of economy, technology and politics. Zinc deposits have increased significantly since 1950, when new large ore bodies were found in different parts of the world. The supply of zinc in the future can therefore not be assessed solely by assuming the supply in today’s mines.