UK based ZincOx started hot commissioning its rotary hearth furnace (RHF) in Korea during Q1 2012 to process electric arc furnace dust (EAFD) to recover both a zinc oxide concentrate and briquetted direct reduced iron (HBI).
The project, being built in two phases, is designed ultimately to treat 400kt/y of EAF dust containing an average Zn content of 23%. The product is a lead containing zinc oxide concentrate assaying at 60%Zn 4.5%Pb which is contracted to be sold to Korea Zinc.
Phase 1 of the operation has a design capacity of 80kt/y of zinc concentrate plus 50kt/y of hot briquetted iron (HBI). When the second phase comes into operation the plant will have a capacity to treat 400kt/y of EAF dust sufficient to process all the EAF dust presently produced in Korea. 160kt/y of zinc concentrate will result from which 92kt/y of zinc metal will be able to be recovered. The process differs from other zinc recovery methods in that DRI is also produced, 100kt/y of briquetted DRI (HBI) being recovered along with the zinc concentrate.
In an interview with Steel Times International, Andrew Woollett, Executive Director ZincOx said they are contracted for the next 10 years to receive all the EAF dust from 26 of the 27 EAF steel plants presently operating in Korea starting in August and will supply a target of 5500 tonnes crude zinc oxide each month to Korea Zinc (66kt/y) once phase 2 is operational.
He continued saying that the plant has now ramped up to about 50% of capacity of zinc concentrate production and has produced HBI with an iron content of 80-85%, but modifications to the briquetting plant are currently being made as it has proved to be insufficiently robust.
Two competing technologies are being voiced by other operators. Global Steel Dust plans to use the long established Wealz kiln, but it is understood that financing of this project which is from Macquarie Bank has not yet been finalized or a site concluded and since ZincOx have contracted all but one steelmaker to supply it with dust little local material will be available should the GSD plant proceed.
Another company, Dongsan S&R, announced plans to set up a joint venture together with Mitsui Metal and Marubeni, a general trading company of Japan, to launch its EAFD recycling business using the Mitsui half shaft furnace with the aim to export most of its crude zinc oxide to Japan. However, industry analysts believe this process can only be feasible if highly subsidised and also, like GSD, will not be able to source sufficient dust locally.