The main objective of the Hydrotreater is to achieve 78% weight removal of organic nitrogen compounds in the gas oil feed stock. In addition to nitrogen removal, the Hydrotreater removes approximately 95% organic sulfur compounds from the feed stock, essentially 100% olefin conversion, provides a significant amount of aromatic saturation, along with metals removal. The resulting hydrotreated gas oil product provides for an excellent Fluid Catalytic Cracker (FCC) feed stock. With improved feed the FCC is able to provide better yields along with lower nitrogen oxide and sulfur oxide emissions.

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  • Feed Inputs: Hydrogen (H2), crude unit Light Gas Oil (LGO) and Heavy Gas Oil (HGO), Light Vacuum Gas Oil (VLGO) and Heavy Vacuum Gas Oil (HVGO), Coker LGO & HGO, and cracked slops
  • Temperature / Pressure: Ambient to 700°F /1700 psi
  • Products / Outputs: Off gas, Light naphtha, Kerosene, LGO, and Hydrotreated HGO
  • Major Equipment Involved in the Hydrotreater Process: Hot & cold feed surge drums, heaters, main & guard reactors, high temperature separator, power recovery turbine, DEA absorber, fractionator, product stripper, LGO stripper/dyer, kero stripper/dyer, heat exchangers, fin fans, compressors, steam generators, selective catalytic reduction (SCR), and pumps
  • Safety Hazards to Consider: Hot oil, volatile H2 & LPG, H2S, lean & rich DEA, ammonia, sour water, steam, and rotating equipment 

Potential Exposure

Hydrodesulfurization is a continuous process and the streams are contained in piping and vessels. The potential for exposure is limited, but can occur during sampling, maintenance, or in the event of a leak, plant upset, or turnaround.

Skin, Eye: The hydrodesulfurizer has the potential for skin contact with distillate and aromatic naphtha streams. Accidental skin contact with the liquid streams may cause slight irritation. Skin irritation can be severe if the liquid becomes trapped inside shoes or gloves. The distillates contain low levels. of polynuclear aromatic hydrocarbons (PNS's), some of which have been shown to cause skin cancer. Avoid prolonged or repeated skin contact with any of these streams by using protective clothing, including impermeable gloves.