Sponge coke

Coke produced from delayed coking is described as delayed sponge, shot, or needle coke depending on its physical structure. Shot coke is the most common when running the unit under severe conditions with sour crude residues. Needle coke is produced from selected aromatic feedstocks. Sponge coke is more porous and has a high surface area. The properties and markets for petroleum cokes have been reviewed by Dymond. Table 3-4 shows the types of petroleum cokes and their uses. ... 

The three main types of coke that are produced in a delayed coker are typically categorized as needle coke, sponge coke and shot coke. Needle coke is a premium grade coke, which is considered a specialty coke and is produced from specific aromatic feedstocks. 

The regular grades of coke are sponge coke and shot coke. A short description of each type of coke follows. 

Shot Coke. Another form, generally undesirable, of regular coke is formed as small spheres often held together in a matrix of sponge coke or in large spheres of shot coke alone. The formation is highly dependent upon feedstocks such as Maya, West Texas Sour and... 

One of the largest uses of petroleum coke is for anodes employed in the production of aluminum. This usage demands a somewhat premium feedstock to produce sponge coke that is low in metal and sulfur content in order to meet product quality specifications. After production in a delayed coker, anode quality coke must be calcined to remove VCM and moisture. 

The green coke obtained with a highly-aromatic feedstock displays needle-like structures and is therefore known as needle coke. If, however, an atmospheric or vacuum residue from mineral-oil refining is used as feedstock, then a foam-like coke (sponge coke) is produced. 

Sponge coke is a mixture of needle and shot coke. The coke formed is spongelike in appearance, and has a dull, black cast. 

When coke is cut from a drum, sponge coke is found along the walls, and shot coke is found in the middle. What causes this segregation ... 

The VCM content of shot coke is similar to that of sponge coke, in the range of 9%-12%. 

Why does some sponge coke look denser and less porous than usual sponge coke ... 

A reduction in coke production cannot be made without producing more shot coke. A certain amount of cross-linked aromatic coke, mixed with the asphaltic coke, is necessary to turn shot coke into sponge coke. This increases total coke production. 

Sponge coke, 46—48, 70 Stack damper, 317-318, 320 process heaters, 317 Stacked paper plates, 94 Stainless steel, 416-418, 424-425 field identification of pipe, 417-418 cracking, 424-425 Start-up stack, 123 Start-up tips (sulfur plant), 134 Start-up (pump cavitation), 246-247 Start-up (sulfur recovery), 122-124 oxygen supply, 123 atmospheric vent, 123-124... 

Why is the coke in the top of a coke drum mostly sponge coke, and the coke in the middle and bottom of the drum mostly shot coke ... 

The heater outlet temperature should be run about 10°F cooler during the first two hours of the coking cycle. This will promote the formation of sponge coke in the coke drum. The procedure will... 

Sponge Coke, Sponge coke is named for its sponge-like appearance. It is produced from feeds that have low-to-moderate asphaltene concentrations. If sponge coke meets certain specifications, it can be used to make carbon anodes for the aluminum industry. Otherwise, it is used for fuel. Green sponge coke must be calcined before it can be used for anodes. Fuel coke may not require calcination. 

Needle coke Sponge coke Shot coke... 

Delayed or retarded coking, which can produce shot coke (a type of fuel coke), sponge coke (used to produce anode coke or as a fuel coke), or needle coke. This process accounts for the majority of the coke produced in the world today. 

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