Dhiraj Gondaliya
Petroleum coke (Petcoke) is marketed as per standard specification or in line with customer specification. There are different grades of petcoke like soft coke, granular, shot coke, fuel grade coke etc. The sulphur concentration in petcoke is a very important parameter for customers due to stricter environment norms. Most of petroleum the refiner estimate petcoke sulphur based on delayed coker unit feed sulphur multiply with fix factor or empirical formula based on the past experience. However many times refinery produce unplanned high sulphur petcock while processing more sour crude or quality give away in petcoke sulphur (very less sulphur compared to specification limit) while processing of sweet crude oil.When unplanned high sulphur petcoke produced, refinery faces many problems like (a) material offtake when sulphur is beyond the specification limit resulting in shortage of committed product to the customers, (b) needs extra storage facility and more time for disposal. To avoid unplanned high sulphur petcoke production, refinery has to process low sulphur crude which is more costly leading to loss in profit margin.