Today, aluminium is the second most-frequently used metal in the world. This is because aluminium has a unique combination of attractive properties - light weight, high strength, very easy to mould and excellent corrosion resistance are only the most important ones. Aluminium is one of the materials of the future. In the long term, the global trend in primary aluminium is very positive. According to forecasts, demand is expected to increase by 50 percent by 2050 and reach well over 100 million tons.
Aluminium features very good recyclability and is one of the most commonly recycled metals. Energy consumption during aluminium smelting is only five to ten percent of the energy used in new production.
Globally, most commercial alumina refineries use the Bayer process to refine aluminium oxide from bauxite ore. Extraction of aluminium from its ore and subsequent processing into finished products takes place in a series of successive operations that are largely independent of each other. The process conditions within the alumina refinery ‒ caustic concentration, temperature, pressure, flow and level ‒ are set depending on the properties of the bauxite ore.
The most significant risk in an alumina refinery is the mechanical overpressure of a digester. There, bauxite ore reacts with caustic soda under high pressure and high temperature. In the past, major explosions have occurred due to failures of process instrumentation devices and pressure relief systems, resulting in major damage to vessels and equipment.
The optimal use of raw materials, energy and process steam can be guaranteed by the use of reliable and accurate flow, pressure, level and temperature measuring instruments from WIKA to ensure strict process control.
After the mixture of petroleum coke, resin, aggregates and recycled used anodes, the mass is shaped (“green anodes”). In the anode furnace, the green anodes are gradually heated to the range of 1,100 to 1,120 °C and slowly cooled again. The entire heating cycle can take 16 to 28 days. The goal of firing the green anode is to produce properties such as sufficient mechanical strength, thermal shock, high electrical conductivity, and low chemical reactivity.
One of the main requirements of anode baking is that all anodes, regardless of their location, are exposed to the same temperatures. For the anode furnaces, WIKA offers a range of accurate, reliable and robust measuring instruments designed to control high temperatures, ultra-low pressures and primary flow elements to optimise the anode baking process, significantly reducing the risk of low-quality anodes.
The bath temperature is one of the most-important parameters for achieving optimum cell operation. It is necessary to measure the bath temperatures as frequently and as accurately as possible.
Thus, abnormalities in the cell can be detected and necessary measures taken to achieve a stable cell operation (e.g. addition of bath additives). WIKA offers a variety of solutions for reliable temperature measurement in aluminium reduction cells.
Precise temperature control is crucial for the efficiency of aluminium plants. Our experience in manufacturing and calibrating temperature measuring instruments enables you to meet your exact requirements and standards.
Low weight with high strength, high load capacity and extreme flexibility ‒ these are the characteristics of modern sophisticated aluminium alloys. The use of aluminium in the construction of modern transportation can save up to a third of the weight ‒ and thus fuel.
In the age of mobility, aluminium is the material of choice. The efficiency of a casting house is measured in cost per ton of aluminium produced. To increase this, it is essential to monitor the temperature of liquid aluminium. The flow temperature of the hot metal is determined while it flows through the channels.
For the temperature measurement of molten aluminium, immersion thermocouples from WIKA are durable and extremely precise.
Precise calibration instruments are the starting point for resolving your test requirements. However, they only form one part of a high-performance calibration system. From our extensive product range, we can design a complete and individual solution for you which contains all the relevant components - with adaptability for test items, pressure and vacuum supply, components for pressure control and fine adjustment, through to voltage supply and multimeters for the calibration of electrical test items.
Our particular strength lies in the project planning, development and the building of complete, individual, application-specific systems – from simple manual work stations through to fully automated test systems in production lines.