CALCINED PETROLEUM COKE

Coke is a fuel with few impurities and high carbon content, usually made from coal. It is the solid carbonaceous material derived from destructive distillation of low-ash, low-sulphur bituminous coal. Coke made from coal are grey, hard, and porous. While coke can be formed naturally, the commonly used form is synthetic. The form known as petroleum coke, or pet coke, is derived from oil refinery coker units or other cracking processes. Coke is used in preparation of producer gas which is a mixture of carbon monoxide (CO) and nitrogen (N2). Producer gas is produced by passing air over red-hot coke. Coke is also used to manufacture water gas. Petroleum coke (often abbreviated pet coke or petcoke) is a carbonaceous solid delivered from oil refinery coker units or other cracking processes. Coking processes that can be employed for making petcoke include contact coking, fluid coking, flexicoking and delayed coking. Other coke has traditionally been delivered from coal. This coke can either be fuel grade (high in sulfur and metals) or anode grade (low in sulfur and metals). The raw coke directly out of the coker is often referred to as green coke. In this context, “green” means unprocessed. Further processing of green coke by calcining in a rotary kiln removes residual volatile hydrocarbons from the coke. The calcined petroleum coke can be further processed in an anode baking oven in order to produce anode coke of desired shape and physical properties. The anodes are mainly used in the aluminium industry. The Petroleum Coke consists of two categories- green coke and calcined coke. These two categories are grouped together in a category based on their similarity of manufacturing processes which results in similar physical chemical characteristics and chemical composition. The principal difference is the amount of residual hydrocarbon (also termed volatile matter) in the two products. Petroleum coke (both green and calcined) is a black-colored solid produced by the high pressure thermal decomposition of heavy (high boiling) petroleum process streams and residues. Green coke is the initial product from the cracking and carbonization of the feed-stocks to produce a substance with a high carbon-to-hydrogen ratio. Green coke undergoes additional thermal processing to produce calcined coke. The additional processing removes volatile matter and increases the percentage of elemental carbon, which results in a lower potential for toxicity for calcined coke. The green coke must have sufficiently low metals content in order to be used as anode material. Green coke with low metals content is referred to as anode grade coke. The green coke with too high metals content will not be calcined and is used for burning. This green coke is called fuel grade coke Petcoke is over 90 percent carbon and emits 5 to 10 percent more carbon dioxide (CO2) than coal on a per-unit-of-energy basis when it is burned. As petcoke has higher energy content, emits between 30 and 80 percent more CO2 than coal per unit of weight. The difference between coal and coke in CO2 production per unit energy produced depends upon the moisture in the coal (increases the CO2 per unit energy?—?heat of combustion) and volatile hydrocarbon in coal and coke (decrease the CO2 per unit energy). The basic raw material, Green Petroleum Coke (GPC), is calcined into the end product called Calcined Petroleum Coke (CPC). Rotary Calcination Technology is being adopted for the Plant as this process shall produce good quality of CPC. The calcined coke industry is considered part of the pyro-processing industry. Its profitability is usually controlled by the aluminium industry’s performance, blending quality, cost of feed stocks and transportation costs. Calcined Petroleum Coke (CPC) is a form of highly electrically conductive, dense Carbon with very low specific Electrical Resistance, and having fixed Carbon of approximately 99.5%. CPC is used extensively as Anode in Alumina Smelters, as Soderberg Electrode for Ferroalloy Industries, and in the manufacturing of Graphite/ Graphite Electrodes, and Thermal Paste for Ferro Alloys & allied industries in Submerged Arc Furnaces. CPC is also used in various Steel Industries- Melting of Steel, Re-caburisation and for making Special Steels & Alloys. Calcined petroleum coke (CPC) is the product from calcining petroleum coke. This coke is the product of the coker unit in a crude oil refinery. The calcined petroleum coke is used to make anodes for the aluminium, steel and titanium smelting industry. CPC is also used in various Steel Industries- Melting of Steel, carburization and for making Special Steels. The feedstock for the project is the Green Petroleum Coke which is a byproduct of the oil refining industry. The quality and impurities of the product comes from the crude oil and depends mainly on the refining process parameters. The calcined petroleum cokes are used in production of aluminum anode-grade, graphite electrode, needle-grade, titanium dioxide pigments.