LIANYUNGANG GUANJI MINERAL PRADUCTS TRADING CO., LTD.
Contact: Manager Wu
Cell phone: 15380685801
Domain name: www.gjmetals.com
Address: Lianyungang Donghai County City Hailing cattle Town Road No. 66
Characteristics of petroleum coke
The indexes of physical and chemical properties of petroleum coke ash, sulfur, volatile matter, true density, porosity, resistivity, thermal expansion coefficient and mechanical properties.
The main elements of petroleum coke ash are iron, silicon, calcium, aluminum, sodium, magnesium, as well as a small amount of vanadium, titanium, chromium and so on. Anode materials used in the production of electrolytic aluminum and the graphite anode of electrolytic Sodium Chloride Solution should limit the content of vanadium in petroleum coke. Influence factors of petroleum coke ash size is the first salt content and degree of desalting of crude oil containing crude oil, the salt after distillation or cracking after processing most enriched in the residue, a small part of the deposition in the furnace tubes, containers, equipment, and most of the salt in the residue in the coke residue. The ash content of the petroleum coke is also influenced by the high pressure water content of the cooling water and the coke discharging, especially the cooling water and the high pressure water which is used repeatedly to use. Out of the production of petroleum coke as piled up in the open air, on the ground of sediment or wind brings sediment will increase the ash content of petroleum coke, petroleum coke ash production of graphite products in general should be less than 0.5%, petroleum coke ash used in the production of high purity graphite should not be greater than 0.15%.
Is one of the sulfur impurities affect the quality of petroleum coke, sulfur and sulfur content on petroleum coke in residue, sulfur residue in 30% ~ 40% residue in petroleum coke, if the higher sulfur content of residue hydrodesulfurization in advance, to reduce sulfur content in residual oil, petroleum coke, sulfur content resulting in reduced. Sulfur in petroleum coke can be divided into two types of sulfur compounds (sulfide, thiol, sulfonic acid, etc.) and sulfur inorganic compounds (iron sulfide, sulfate). Generally calcined to about 1300 degrees desulfurization effect is not large, only the calcination temperature can be increased to about 1450 degrees in order to have a more obvious desulfurization effect, a part of the sulfide needs to be discharged at high temperature of the graphite. The production of aluminum electrolysis anode materials and the production of graphite products, sulfur is a harmful element, containing large amount of petroleum coke production of graphite electrode in graphite "phenomenon in the process of flatulence", easily lead to crack. Graphite electrode with high sulfur content in steel making, steel electrode increased consumption of petroleum coke, sulfur Chinese most low origin, only the use of domestic high sulfur crude oil and imported high sulfur crude oil refinery production of high sulfur petroleum coke.
Petroleum coke volatile size showed that the coking temperature, kettle type coke coking temperature higher, up to 700 degrees Celsius, so the kettle type coke volatile low (3% ~ 7%), and delayed coking coking coke temperature is only 500 degrees Celsius, so volatile is as high as 8% ~ 15%, delay coking production of petroleum coke and its volatile depends not only on the coking temperature, and residual oil into the coke tower loading time and related to the coke layer steam blowing conditions, coke volatile same tower unloading points are different, such as in the structure of coke tower bottom is dense, volume density, volatile low coke and loose structure at the top of the tower, much more volatile. How much the quality of carbon products there is no petroleum coke volatile much impact, but have effects on the calcination have difficulty in operation, high volatile petroleum coke using the general structure of the rotary kiln or tank furnace, the need for the necessary transformation of the calcination equipment, in order to adapt to the burning high volatile petroleum coke needs.
Petroleum coke calcined at 1300 DEG C true density size is one of the major projects, to measure the quality of petroleum coke calcined in general, true density is higher, the easy coke graphitization and graphite after low resistivity and low thermal expansion coefficient, showing the dense degree of coke structure form the bulk density of petroleum coke. And is proportional to the mechanical strength. In addition to the density of the coke and the volume density of coke, but also related to the particle size of coke.
The resistivity of calcined coke is very high, close to the insulator, after calcination, the resistivity decreased sharply, petroleum coke resistivity and the calcination temperature is inversely proportional to the temperature of 1300 DEG C calcined petroleum coke resistivity is reduced to 500 m or so.
Coefficient of thermal expansion
Properties of petroleum coke thermal expansion coefficient mainly depends on the residue, namely the content and content of asphaltene in aromatic hydrocarbons, aromatic hydrocarbons and high asphaltene content and low residue, produce petroleum coke and its low coefficient of thermal expansion, needle coke is such as coke, petroleum coke, thermal expansion the coefficient is different (see table 1), the production of large size ultra high power graphite electrode material should lower expansion coefficient by hot needle coke. The thermal expansion coefficient of petroleum coke is related to the test temperature. The standard temperature of thermal expansion coefficient of China is 100 to 600.
The mechanical properties of petroleum coke include "broken", brittleness and wear rate of petroleum coke "can be broken and brittle in the electrode manufacture has certain practical significance in the process can be broken with coke in the size ratio evaluation before and after crushing, and brittleness is broken in the possibility of coke said in the process of transport and transport. Test method for characterization of petroleum coke wear rate is the drum test, wear rate and volatile content is proportional to the original coke, and inversely proportional to the volume density of calcined petroleum coke wear rate decreased significantly.