Sub-Product

Main Product: Coke
Segment: Refined Products
Main-Family: Refinery Residues
Sub-Family: Coal & Petroleum Residues
Physical State: Solid

Sub-Product

Needle Coke

Description

Needle coke is produced in a Delayed Coker from aromatic petroleum or coal tar heavy residues. They generally form as highly crystalline graphene-like carbons, exhibiting long-range microstructural order with minimal Impurities (Sulphur, Nitrogen, and metals) and a low Coefficient of Thermal Expansion (CTE).

Historically, needle cokes have been used to produce graphite electrodes for steel smelting in an Electric Arc Furnace (EAF). The advent of EVs has additionally diversified the scope of application for needle coke (inclusion in graphite anodes of Lithium ion batteries).

Needle Coke quality is generally classified into three quality grades (Ultra Premium, Super Premium and Intermediate Premium), the specifications of which are presented in the following table:

	Ultra Premium	Super Premium	Interm. Premium
CTE value, x 10^-6/°C	0.25	0.35	0.6
Sulphur content, wt%	Trace	0.2-0.4	0.4-0.6
Nitrogen content, wt%	Trace	<0.2	<0.3
V/Ni content, ppm	Trace	<10	<10
Ash content, wt%	<0.1	<0.2	<0.3
Real density, g/cm³	2.15	2.13-2.15	2.13-2.14
Hydrogen content, wt%	Trace	0.03-0.05	0.03-0.05

The two main Utra-Premium Needle Coke precursors stem from the petroleum industry as FCC decant oil (FCCDO) and from the coal blast furnace industry as high-temperature coal tar pitch (HT-CTP).

Source: DIGITAL REFINING, Nov 2022, M. Wagner da Silva, J. Clark, Needle coke — overcoming quality challenges in a resurgent market.