ELTRA GmbH has over 30 years of experience in the construction of elemental analyzers for the determination of the carbon, sulfur, nitrogen, oxygen and hydrogen content in a variety of ferrous materials such as steel or cast iron. Several analyzers have been specially optimized for in-process analyses and final quality control of such products.
The essential stations of steel production are the blast furnace, converter and finishing. After each step the determination of the C, H, N, S, O content is required for quality control.
In the blast furnace pig iron is produced from iron ore, coke and lime, along with the by-product slag. The burning of coke generates temperatures of up to 1,400 °C inside the blast furnace, which is 30 to 50 meters high. At this temperature, iron ore liquefies and is at the same time chemically reduced through the carbon monoxide coming from the coke.
At the end of this process the pig iron still has a very high carbon content of up to 7 % which is reduced in the converter where scrap metal and, if required, more lime are added. Oxygen is introduced which substantially reduces the existing carbon content by forming gaseous CO2. After this oxidizing process the iron melt can be alloyed with other metals (e. g. chrome, nickel, vanadium, cobalt). Finally, this melt is used to produce the end product.
Elements such as carbon and sulfur substantially influence the hardness and processability of materials such as titanium, zirconium or carbide; therefore, it is paramount to reliably determine these elements as part of the quality control process with an elemenal analyzer. While the powerful induction furnace of the carbon sulfur analyzer CS-i combusts a metal sample in an oxygen stream at more than 2,000 °C, infrared cells ensure the reliable determination of carbon and sulfur.
Analysis of the oxygen and nitrogen content is routinely carried out for all types of steel. For stainless steel analysis of the hydrogen content is also relevant. The oxygen / nitrogen / hydrogen / analyzer ONH-p is equipped with an impulse furnace and provides temperatures of more than 3,000 °C. It reliably measures the hydrogen, oxygen and nitrogen content in ferrous samples.
The effective calorific value of fuels is determined by their carbon and hydrogen content. Through combustion the contained hydrogen turns into a substantial amount of water which evaporates from the boiler and is therefore not usable for the heating process. This is of interest for coking plants which are part of steel plants.
The CHS-r and CHS-580A analyzers reliably determine the carbon, hydrogen and sulfur content. The CHS-580A is available with an Autoloader which accommodates either 36 or 130 samples.
Carbon occurs as bound in a material (total carbon) but is also found on the surface of materials (surface carbon). Process water or oil can contaminate the surface of a product thus preventing or impeding further processing such as painting/varnishing. The SurfaceC-800 is equipped with an XXL sample drop mechanism, allowing for reliable analysis also of large sample pieces.