Metal

Graphite electrodes serve to transfer the electrical energy from the power supply to the steel melt in the EAF bath. They are typically made using premium petroleum needle coke, coal tar pitch, and some additives.

Electrode consumption varies between 1.8 and 9.9 kg/t of liquid steel (Parkash, 2010) depending on the process characteristics and electrode quality. Ameling et al. (2011) reported that the electrode consumption in Germany in 2010 was approximately 1.1 kg per ton as a result of the reduction of time between the taps to 40 min and consequently the lower electricity consumption (345 kWh/t). Electrodes are classified as regular grade or premium grade on the basis of their physical properties (International Iron and Steel Institute, 1983).

For DC Furnaces (direct current furnaces) / Size: 22-32 inches

Electrodes for DC furnaces, which require 1 column of graphite electrodes. High maximum current density. The diameter of these electrodes is getting bigger: the current maximum diameter is 32 inches (801 mm).

For AC Furnaces (alternating current furnaces) / Size: 16-28 inches.

Alternating current furnaces require 3 columns of graphite electrodes. They mostly use 20-28 inch electrodes, the standard size in electric furnaces.

For LF Furnaces (refining furnaces) / Size: 10-18 inches

These electrodes are for refining materials like molten steel. LF Furnaces have a smaller capacity than DC.

Bath Material is also commonly referred to as Secondary Cryolite, Crushed Bath, Bath Cryolite, PureBath, Bath and tapped Bath Material. Surplus Bath Material is generated during the aluminium smelting process as a result of high Sodium (Na) content in the alumina.

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Electric arc furnace dust (EAFD) is a waste from steel recycling in an electric arc furnace. Due to the waste mainly consisting of zinc ferrite along with a small amount of heavy metals such as lead and chromium, EAFD is categorized as a toxic waste. Even though proper treatments of EAFD offer crude zinc oxide and iron oxide, such appropriate EAFD recycling techniques have not yet been established in Thailand. The simplest way to reduce its toxicity is glassification. According to the EAFD’s chemical composition, it is possible to use it as a raw material in decorative ceramic glazes which contain zinc and iron oxides.

Zinc bearing wastes such as electric arc furnace dust (EAFD) obtained from steel making constitute an important resource for zinc extraction. Inclusion of heavy metals such as Pb, Cd, Cu, Cr, Ni, etc., in these wastes makes them hazardous to use and/or dispose. In the present research work, leaching kinetics of EAFD with sulfuric acid has been investigated and various experimental parameters such as concentration of lixiviant, stirring rate, sample particle size, liquid/solid proportion, and temperature of the reaction have been optimized.

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Alumina, also called aluminum oxide, synthetically produced aluminum Oxide, Al_2O3, a white or nearly colorless crystalline substance that is used as a starting material for the Smelting of aluminum metal. It also serves as the raw material for a broad range of advanced ceramic products and as an active agent in chemical processing.

Alumina is made from bauxite, a naturally occurring ore containing variable amounts of hydrous (water-containing) aluminum oxides. Free Al₂O₃ occurs in nature as the mineral corundum and its gemstone forms, sapphire  and ruby; these can be produced synthetically from alumina and in fact are occasionally referred to as alumina, but the term is more properly limited to the material employed in aluminum metallurgy, industrial ceramics, and chemical processing.

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Zinc smelting is the process of converting zinc concentrates (ores that containzinc) into pure zinc. The most common zinc concentrate processed is zincsulfide, which is obtained by concentrating sphalerite using the froth flotation method.

NGN offers zinc concentrate with a majority zinc base component. Preparation of zinc concentrate typically involves the removal of water from an zinc solution. 

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Prebaked Consumable Carbon Anodes are a specific type of  anode designed for aluminium smelting using the  Hall-Heroult process.

The properties of the anode are largely set during the baking process and must be carefully controlled to ensure an acceptable output efficiency and reduce the amount of undesirable byproduct produced. To that end, the aluminium smelting industry has settled on a range of acceptable values for commercial mass-produced anodes for the purpose of consistent, optimal performance.

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Cryolite is a mineral, sodium aluminum fluoride, Na3 AlF 6, occurring in white masses, used as a flux in the electrolytic productionof aluminum.

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Alumina is reduced to metallic aluminum in an electrolytic cell called a "pot", which is made up of two main parts - one serves as the anode or positive electrode of the cell, and the other, as the cathode or negative electrode. The anode consists of a block of carbon formed by baking coke and pitch, while the cathode is found in the carbon lining of a large steel container located under the anode. This lining is formed by baking metallurgical coke and pitch.

The space between the anode and the cathode is filled with an electrolytic bath of sodium aluminum fluoride, or cryolite. The electrolyte is heated to about 980°C, at which point it melts and the alumina is added and dissolved. An electric current is then passed through the mixture to split the alumina into molten aluminum metal at the cathode and carbon dioxide at the anode.

This Hall-Héroult process was invented in 1886 and has since been steadily improved. Currently, it takes about 2 tonnes of alumina to produce 1 tonne of aluminum metal.

Smelting consumes huge amounts of electricity because of the high temperatures that must be generated. Typically, the electrolysing current is delivered at a high amperage and on average, it takes almost 14,171 kwh of electricity to produce 1 kg of aluminum from alumina compared with XinRen's average of 13,727 kwh in 2009. In addition, the smelting process is continuous as the metal in the pots cannot be allowed to solidify. Not surprisingly, most plants around the world are located in areas where there is ample access to inexpensive energy.

A cathode block is a negative electrode and is used in the lining of aluminium reduction cells. A cathode block has the properties of superior electrical and thermal conductivity, high chemical and bulk stability, as well as high strength in electrolysis under high temperature. Sidewall blocks, ramming pastes, and special glues round out the cathode product portfolio, providing complete custom-made solutions to optimally fit the requirements in the aluminium smelter.

Compared with conventional amorphous carbon or graphitic blocks, our fully graphitized cathode block offers high thermal and electrical conductivity and higher resistance against thermal shock and contributes to energy savings, higher productivity, and longer pot life.

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