Three factors affecting smelting of graphitized petroleum coke

Three factors affecting smelting of graphitized petroleum coke

The predecessor of graphite petroleum coke was the coking unit used for thermal processing in the petrochemical industry, which mainly processed petroleum coke and some residual light oil products with poor quality, which were difficult to further process. The decoking of natural stone production will also be divided into ordinary petroleum coke and good petroleum coke, petroleum carburizer, which is also the starting point of graphitized petroleum coke. The main difference between the two is whether they are used as raw materials for advanced graphite products such as graphite electrodes.

Graphitization can reduce the impurity content, increase the carbon content, and reduce the sulfur content. Carburizers for casting can greatly increase the consumption of scrap steel, reduce the consumption of pig iron or not use pig iron.

The charging method for electric furnace smelting should be to put the carburizer into the furnace together with scrap steel and other furnace materials, and a small amount can be added to the surface of the molten iron. However, it is necessary to avoid adding a large amount of material to the molten iron to avoid excessive oxidation resulting in unclear carburizing effect and insufficient carbon content in the casting. The amount of carburizer added is determined according to the proportion and carbon content of other raw materials.

Graphitized petroleum coke has three major effects on smelting

1. Carburizing technology of molten iron can increase graphite nuclei during smelting, especially in electric furnaces. Adding silicon carbide in cupola smelting can also increase the feldspar graphite nuclei of molten iron and reduce oxidation of molten iron.

2. Carbonization is a measure to prevent or reduce the tendency of shrinkage. Due to graphitization and expansion during the solidification of molten iron, good graphitization will reduce the shrinkage tendency of molten iron.

3. Under high carbon content conditions, in order to obtain high-strength gray cast iron castings, the smelting process uses scrap steel and carburizer to make the molten iron purer and produce castings with high material properties. Clean materials without pollution should be used during smelting to avoid leakage or excessive scum.

In general, the quality requirements of ordinary petroleum coke are not high, and the light oil products produced are also low-quality oil products with high residual carbon value and high metal technology content. Only through secondary processing methods can qualified oil products be developed. However, natural graphite appears in nature, and people in the foundry industry often use graphite because artificial graphite has many advantages, such as the porosity, carbon content, and graphitization degree of artificial graphite, which can better meet the requirements. At the same time, petroleum coke is mainly used to produce graphite.