Classification of petroleum coke

Petroleum coke is classified according to its sulfur content into high sulfur coke (sulfur content over 4%), medium sulfur coke (sulfur content between 2% and 4%) and low sulfur coke (sulfur content below 2%). China's delayed petroleum coke quality standard (ZBE44002-86) divides petroleum coke into No. 1, No. 2 and No. 3, each of which is further divided into A coke and B coke, stipulating that the sulfur content of No. 1 coke should not be greater than 0.5% (A coke) and 0.8% (B coke), that the sulfur content of No. 2 coke should not be greater than 1.0% (A coke) and 1.5% (B coke), and that the sulfur content of No. 3 coke should not be greater than 2.0% (A coke) and 3.0% (B coke). The sulfur content of No. 4 A coke is 3%~5% and No. 4 B coke is 5%~7%.