Research on treating processes of Nickel Laterite Ores in the world and Vietnam

Laterite nickel ores, accounting for about 70% of total world nickel reserves, are very abundant and considered as an important resource of nickel. However, nickel content of laterite ores are generally low of about 0.5÷2.5% Ni. In addition, nickel minerals are very finely disseminated in the ores, so that traditional separation methods such as froth flotation, gravity method, magnetic method, and electrical separation produce very low recovery efficiency. Currently, the treatment of this type of ores is being intensively studied and directed to use common available processes including: Hydrometallurgical, pyrometallurgical, and reduction roasting - magnetic separation processes. This article aims to summarize typical studies on the characteristics of current laterite nickel ore processing technologies commonly used in the world and in Vietnam. From the review, appropriate direction for treatment of Thanh Hoa - Vietnam laterite nickel ores can be proposed.

Pengaruh Karakteristik Bijih pada Ekstraksi Nikel dari Bijih Limonit Indonesia menggunakan Pelindian Atmosferik

AbstrakKebutuhan ekstraksi nikel dari bijih nikel laterit khususnya jenis bijih limonit dengan kadar nikel yang rendah sangat diperlukan karena kebutuhan nikel yang terus meningkat dengan adanya pengembangan kendaraan bermotor listrik berbasis baterai. Jenis dan karakteristik bijih laterit yang berbeda akan memberikan pengaruh pada hasil ekstraksi nikel. Pada penelitian ini dilakukan ekstraksi nikel dari bijih laterit jenis limonit yang berasal dari Pulau Halmahera (LH)) dan Pulau Sulawesi (LS) menggunakan pelindian atmosferik. Asam sulfat digunakan sebagai agen pelindian. Penelitian dilakukan untuk mengetahui pengaruh karakteristik bijih limonit (LH dan LS) pada berbagai variabel pelindian yaitu suhu (30oC, 50oC dan 80oC), konsentrasi asam sulfat (0,5M; 1M; dan 2M), waktu pelindian (15, 30, 60, 120, dan 240 menit), serta rasio bijih terhadap reagen pelindian (5, 10, dan 20% w/v) terhadap ekstraksi nikel dari bijih limonit. Hasil penelitian menunjukkan bahwa karakteristik bijih laterit sangat berpengaruh pada hasil pelindian dan persen rekoveri nikel. Nikel dari bijih LH yaitu jenis limonit dari Pulau Halmahera dapat diekstrak secara maksimal (100%) pada konsentrasi asam sulfat 0,5M, suhu 80oC, rasio bijih/larutan asam sulfat 10%, dan waktu pelindian 2 jam. Sedangkan persen ekstraksi nikel dari bijih LS yang terbesar adalah 95% yang diperoleh pada konsentrasi asam sulfat 2M, suhu 80oC, rasio bijih/larutan asam sulfat 5%, dan waktu pelindian 4 jam. AbstractNickel extraction from nickel laterite ores particularly low-grade limonite ore is needed along with the increase of nickel consumption on the development of battery electric vehicle. Types and characteristics of nickel laterite ores affect greatly on the nickel extraction from these ores. This research conducted the extraction of nickel from limonite ore from different areas i.e. Halmahera Island (LH) and Sulawesi Island (LS) using atmosferic leaching. Sulfuric acid (1M) was used as leaching reagent. Leaching processes were carried out for investigating the effects of limonite ore characteristics (LH and LS), leaching temperatures (30oC, 50oC dan 80oC), concentration of sulfuric acid (0.5M; 1M; 2M), leaching time (15, 30, 60, 120, and 240 minutes), and ratio of ore amount to volume of leaching reagent on the nickel extraction from limonite ores. Experimental results showed that ore characteristic affected greatly on the leaching result and nickel leaching recovery. Nickel from LH ore could be extracted maximum (100%) using sulfuric acid 0.5M, temperature of 80oC, and leaching time 120 minutes (2 hours). Whereas, the highest nickel extraction percentage from LS ore is 95% using sulfuric acid 2M, temperature of 80oC, and leaching time 240 minutes (4 hours).

A Semi-Empirical Water and Energy Analysis of Industrial Production of Nickel From Mineral Ores: Comparative Analysis Between Two Different Technologies of Calcination

In the ferronickel production process, mineral calcination is one of the most energy-intensive stages. In a typical rotary kiln calciner, particulate solids and combustions gases move counter currently, while solids undergo drying, pre-reduction, and partial reduction reactions. The combustion of natural gas provides the thermal energy for drying and reduction reactions. About 80 to 85% of the incoming laterite ore leaves the reactor as calcined ore, while the flue gases entrain part of the solids as dust. This work presents a theoretical analysis contrasted with experimental results to evaluate the partial reduction of laterite ores in two rotary kilns of 185 m and 135 m length. The study focused on the water formed in the process, including a comparative analysis of water consumption by two different solids recovery technologies, a gas scrubber and an electrostatic precipitator. Simulations allowed evaluating the water and greenhouse gas formation in the main streams of the process. Among the tested operation conditions, the moisture content in the pellets, consisting of agglomerated dust, strongly influenced the amount of water released in the process and the energy consumption. Furnace RK-2 needs approximately 56% more energy to evaporate the moisture content in the feedstock. Furthermore, furnace RK-2 released 55.4 m3h−1 of water into the atmosphere, which represented two times the amount released by furnace RK-1. Gas scrubber analysis showed that as the liquid water increased, more H2O in the gases was condensed; however, the destroyed exergy also increased. Electrostatic precipitators appear as an adequate technology for reducing water and energy consumption in the ferronickel industry.

The Study of Physicochemical Features of Laterite Ores of the Buruktalsky Deposit

Currently, there are practiced various pyrometallurgical, hydrometallurgical, and com-bined pyro and hydrometallurgical methods for processing of oxidized nickel ores to produce metal-lic nickel, cobalt, and their compounds in non-ferrous metallurgy. The problem is the difficult ore concentration, and consequently the high consumption of reagents or low extraction of valuable components from it. Ural plants previously implemented the technology of reducing-sulphiding smelting of laterite ore to produce fire nickel and transfer of cobalt to matte. The economic ineffi-ciency of this technology predetermined the search for a new method for processing of significant reserves of oxidized nickel ores in the Ural region.

Review of the past, present, and future of the hydrometallurgical production of nickel and cobalt from lateritic ores

Laterite ores are becoming the most important global source of nickel and cobalt. Pyrometallurgical processing of the laterites is still a dominant technology, but the share of nickel and cobalt produced by the application of various hydrometallurgical technologies is increasing. Hydrometallurgy is a less energy-demanding process, resulting in lower operational costs and environmental impacts. This review covers past technologies for hydrometallurgical processing of nickel and cobalt (Caron), current technologies (high-pressure acid leaching, atmospheric leaching, heap leaching), developing technologies (Direct nickel, Neomet) as well as prospective biotechnologies (Ferredox process).