(FLINK) INTL. SYMP. ON SUSTAINABLE PRODUCTION OF FERRO-ALLOYS

In 1907 the large Göta river waterfalls in Trollhättan started to be developed to produce electric energy, more or less, simultaneously negotiations were ongoing with Wargön Bruk AB to acquire the fall rights at Wargön Bruk AB’s property in the same Göta river about 7 km upstream from Trollhättan. A contract was signed where Trollhättan’s Vattenfall acquired the fall rights but Wargöns Bruk AB had to accept a 40-year long contract to pay for 4000 hp consumed or not. Everybody was happy until the first invoice arrived, and no plans were done on how to consume 4000 hp. After a quick survey in the paper mill, a possible consumption of 1000 hp were found where to consume the rest
The following was found and discussed;
One of the major owners of the company had a manganese mine in his possession
Tests to produce SiMn had been performed in Norway with good results.
Char coal if needed was available, within the company to be used as reducing assets
Good quality quartzite was available at 100 km north of the company and could be shipped by a vessel over the lake Vänern
Second-hand equipment could be purchased in Trollhättan
The electric power was available
In December 1911 it was decided to build a ferroalloy plant close to the paper and pulp plant, and just at 100 m from the river.
In January 1913 a board meeting tells that the alloy plant produced about 600 tonnes of SiMn and FeSi during 1912.
A century later the alloy plant still exists on the same spot. The paper and pulp mill is closed for some years. That mill was sold already in 1969 and the alloy plant lived by itself.
The alloy plant has today 4 units and is producing HC FeCr of various grades. It is procured with raw materials (Chrome ore) from the group’s own mines in Turkey and Kazakhstan. As initially, the company operated as an integrated plant producing various Manganese products using company Manganese ore resources it is today back as an integrated producer. Now for various Cr-products with based on internal Chrome ore resources.

As the highly respectable Mining Journal (issue 20. May 2019) recently stated: “Mining may have pedigree, with its roots in the Bronze Age, but with direction and momentum established over some 5,000 years it also has the turning circle of the QEII and, as such, has long been regarded as an innovation and technology laggard among industries.” This reputation is currently changing fast with major international mining companies and the World Bank Group jointly promoting “The growing role of Minerals and Metals for a Low Carbon Future” [1].
Traditional comminution systems for ores such as ball and SAG mills are trusted for their robustness but also known for their inefficiency, particularly in energy consumption and general rock breakage [2]. With more than 50 % of energy being consumed in a typical mining operation for crushing and milling and – even worse – only 1 % of the energy consumed by a conventional ball mill used for breakage and the rest wasted as heat, there is huge potential for radical improvement.
The VeRo Liberator^® was invented some 6 years ago and achieves high-velocity, high-frequency impact comminution through a vertical four-fold axle-in-axle system with hammer tools, rotating clockwise and anticlockwise [3]. The impacts produce highly turbulent particle flow and trigger fracture nucleation and propagation at and along phase boundaries. With energy consumption being reduced by over 70 % and particle liberation far superior to conventional systems, this new technology offers huge operational and economic advantages. The VeRo Liberator^® operates dry and thus produces waste that does not require dewatering and allows for safer direct dry stacking.
The VeRo Liberator^® achieves its drastically energy-efficient particle size reduction and particle liberation by high-velocity impacts that achieve an efficient momentum transfer into the ore particles. This leads to the disintegration or quasi “explosion” of the ore particles, predominantly without actual contact with the impact tools. Consequently, the VeRo Liberator^® uses less energy, shows surprisingly little wear, and operates at very low noise levels. Market entry of the VeRo Liberator^® technique was achieved in 2017 and several units are now performing in industrial-scale operations or are on their way to installation for Anglo American. It is now up to the wider mining industry to test and embrace the new technology and develop it to its full potential.

Founded in 1990, Bear Metallurgical Company (“Bear”) is the sole independent toll converter of ferrovanadium and the largest producer of ferromolybdenum in the United States. The core business of the Company is the toll conversion of vanadium oxide to ferrovanadium and the conversion of molybdenum oxide to ferromolybdenum. Since its founding, the company has developed and adopted various advanced production and managing practices to achieve a sustainable development of the company as a leader in ferro-alloys production. This paper gives an overview of the company history, its industrial processes and its products and then focuses on measures undertaken to achieve a sustainable development that simultaneously achieve (1) economic growth by adopting lean production principles that increase the quality and efficiency and reduce cost (2) protection of the environment by adopting high recyclability and waste treatment schemes and (3) development of the society by increasing the quality of the working conditions, assuring accident free production for record lengths of time and helping communities in the area.

The Gentio do Ouro Golden District is located on the western edge of the Chapada Diamantina, the central region of the State of Bahia, Brazil. The principal ore-related geological caracteristics of the study are include the presence of Proterozoic gabbroic sills in the lower portion of the Espinhaço Supergroup [1]. The mafic sills were subsequently affected by hydrothermal (metasomatic) alteration that is associated with the emplacement of a first phase of gold mineralization along the contacts between the sills and the wall rocks [2]. Quaternary surface weathering [3] led to the development of thick zones of supergene alteration predominantly developed along topographic highs and which include saprolit, latossol, duricrust and pisolite. Protolithe composition was established geochemically and more particularly through the sydtemstic use of the Fe2O3 (T)/MgO ratio that is considered to be representative of the initial composition of the rocks. The formation of supergene-altered layers through weathering under lateritic conditions, evolved from the parental rocks towards saprolit-latossol-duricrust-pisolite, predominantly in response to partial dessilicification and coprecipitation of trace elements with iron oxides/hydroxides. The dissolution of primary gold occurred in the presence of chemical complexes such as sulphates and sulphites, were produced by the oxidation hydrothermal auriferous sulphides in the presence of carbonates [4]. Mobilized gold was transported under oxidizing conditions as colloidal gold and subsequently precipitated in an array of ferraneous fractures, or filling micro-cavities [5]. The lateritic weathering processes responsible for the mobilization of gold and its secondary precipitation are responsible for its local enrichment, an increase of purity (all other associated trace metals being separated from gold), and, ultimately in the development of nuggets in lateritic materials. Samples of the parent rock and its lateritic products were search for geochemistry with the purpose to study the mobilization and concentration of major, trace and rare earth elements on profile of chemical weathering of gabbroic rocks.
The geochemical analysis for major and trace elements was measured by atomic absorption spectrophotometry and ICP – inductively coupled plasma. The results for lanthanides was normalized to chondrites [6].

FLOGEN Decision Making, Control and Optimization system has been applied to the production of FeSiMn alloy production in an electric furnace.
This resulted in simultaneously reducing the specific energy consumption,
decreasing Mn losses in the slag, better control of allow specifications and greater flexibility in using multiple raw materials. This paper will present the general features and control system as well as the main results

Self-organizing jet emulsion reactor (SER), during generation of which some principles of theory of self-organization and a number of interesting physical effects were used, is of certain degree of universality. Pilot installation has demonstrated possibility of implementing several low-energy and even waste-free technologies on it, including: direct reduction of dust-type ores and waste without agglomeration, production of manganese alloys from poor dust-type concentrates, waste-free separation of titanium-magnetite concentrates into metal and conditioned titanium slag, etc.
Presented report focuses on technology of direct reduction of manganese in JESI from dust-type ores and concentrates, including oxidized and carbonate ones. Specifics of technology is generation of full cycle of combustion products recycling, which allow for preliminary recovery or roasting of manganese ores in fluosolid unit connected to the output of the main unit, and reduction of energy costs for production of manganese alloys.

The region of North Gemer (Slovakia) is rich in mineral resources which provided good conditions for the development of mining more than 600 years ago. The mining company Siderit in Nižna Slana was one of the most important industrial companies in Gemer w hich dealt with the processing and extraction of iron ore. During operation, the company has emitted solid pollutants to the nearer and farther environment, which are associated with hazardous heavy metals and gaseous emissions of sulfur oxides and nitrogen oxides. The natural dispersion of the pollutants has unfavorable conditions due to the location of the plant in the valley of the river Slana. Mining and metal processing are responsible for the extensive contamination and pollution of soils and water. In particular, old mining works, heaps and sludge basins have become a significant source of surface pollution. The work presents the results of soil research conducted in 2018, 10 years after enclosing the Siderit's operations. The research was carried out at 11 sites which are located in the pollutant field of the tailing impoundment, as well as on the surface of the tailing impoundment. The results showed that, in the soils, there is above-limit content of Hg, As, Ni, Cd, Pb and Fe. The highest measured concentrations exceeded the limit of As by 37.0 times, Hg by 4.0 times, Cd by 2.7 times, Pb by 1.9 times, Ni by 1.4 times and the highest values exceeded the average Fe content up to 6 times compared to limit values set by Act. No. 220/2004 Coll. Based on research results, we can conclude that soils are heavily contaminated with heavy metals, which pose a serious risk to public health, contamination of agricultural production and threats to groundwater and surface waters.

Falconbridge Dominicana (Falcondo) has a long operating history since 1955 and in August 2015 Americano Nickel Ltd acquired the company from Swiss miner Glencore. After two interruptions to operations in the periods 2008-2011 and 2013-2016, the company resumed production in April 2016 under new management.
With a total installed Ni capacity of 32000 t annually, it makes Falcondo one of the 10 biggest producers worldwide.
The main difficulties that were required to confront were: market conditions, loss of customers after the period of care and maintenance, and an atmosphere of uncertainty and mistrust within the country.
Falcondo managed to overcome the difficulties taking initiatives to increase profitability, through the introduction of new and more effective methodologies and technologies, both in the mining operation and in the operation of the plant, reducing also the environmental impact.
Falcondo won the price of the biggest exporter in the Dominican Republic for 2019 and in that way the country takes a position between the biggest exporters of Ferronickel together with China, Finland, the United States, Italy, Netherlands, Switzerland, Spain, South Africa, Sweden, and India. In this paper, factors that made Falcondo a successful sustainable producer of Fe-Ni in terms of economic growth, environmental protection and social development along with the description of the process and technological improvements

The production of ferromolybdenum at Bear Metallurgical is carried out by reducing the Molybdenum Trioxide (MoO3), contained in primary or recycled materials using FeSi (and sometimes aluminum) as a main reductant, iron or iron oxide as alloy formation agents and lime as slag conditioner in a so-called silicothermic reaction which provides the necessary heat for the process and avoids the need for extra sources of energy. In this paper, the production flowsheet from the receipt of the primary materials, to batching, blending, smelting and then crashing, sampling, product specifications and quality testing are described along with the characteristics of this special silicothermic process related to molybdenum reaction, its speed energy and temperature, furnace separation, process control, efficiency as well as and its special reactor furnace

The production of ferrovanadium at Bear Metallurgical is carried out by reducing the Vanadium Pentoxide (V2O5) contained in ores or in recycled materials using aluminum as a reductant and iron as alloy formation agent in a so called violent Aluminothermic reaction which is properly controlled during the process. Although the process is straightforward, the nuances in the production make it a complex one. In this paper the production flowsheet from the feed preparation to blending, from smelting to product specifications and quality testing are described along with the characteristics of this special aluminothermic process related to its speed and temperature, its control and efficiency as well as and its special reactor furnace.

The main method of production of the most common ferroalloys such as ferromanganese, ferrosilicon, ferrochromium is the electric furnace. The energy of this furnace is based on the combined use of electrical energy to create the necessary heat that is released in the area of ​​the electrodes as well as in the charge when an electric current passes through it. The advantages and disadvantages of this method of supplying energy are well known. One of the disadvantages is increased energy consumption and reduced productivity.
ORIEN Technology is a new method for producing of ferroalloys, which differs from the existing methods of using electric arc heating as a heat source, which is typical for electric arc steel furnaces operating with high electric voltage.
The most characteristic feature of this innovative solution is the combination of raw material supply and carbothermic reductions by preliminary agglomeration ore (as raw materials) with carbon (as a reducing agent) and continuous supply of agglomerated materials into the combustion zone of the electric arc.
This method is a further development of steel production technology - that bear the same name: ORIEN process. This new technology reduces energy consumption, increases productivity, expands the range of ferroalloys and improves their quality. This process can use natural ore as raw materials as well as poor ores with low content of alloy elements.

Fully mechanized underground mining is a valuable method to achieve sustainable development in the mining industry because it achieves simultaneously (1) economic growth and profitability by increasing efficiency and decreasing cost (2) protects the environment by decreasing the specific use of energy and as a result decreasing CO2 emissions and (3) develops the society by reducing and eliminating the life and accidental risks of the miners and improving their quality of life since a part of the increased additional profit of the company is distributed to them also to their community. This paper the experience and results of applying for the first time in the chrome industry of Turkey of an underground fully mechanized method along with its multiple advantages.