Table of Contents
What is the need of hydrocracking?
A hydrocracking unit, or hydrocracker, takes gas oil, which is heavier and has a higher boiling range than distillate fuel oil, and cracks the heavy molecules into distillate and gasoline in the presence of hydrogen and a catalyst. …
What is the hydrocracking process?
Hydrocracking is a process to convert larger hydrocarbon molecules into smaller molecules under high hydrogen pressure and elevated temperature. It is commonly applied to upgrade the heavier fractions of the crude oils to produce higher value transportation fuels.
Why is hydrocracking more effective than FCC?
In a refinery, the hydrocracker upgrades VGO through cracking while injecting hydrogen. This yields a high volume of high-quality diesel and kerosene product. This is in contrast to the FCC, which uses the same feed (VGO) but produces more and better-quality gasoline.
What’s the difference between hydrotreating and hydrocracking?
The key difference between hydrocracking and hydrotreating is that hydrocracking includes the conversion of high boiling constituents into low boiling constituents, whereas hydrotreating includes the removal of oxygen and other heteroatoms. Hydrocracking and hydrotreating are useful processes in petroleum oil refining.
What is the by product of hydrocracking?
The major products from hydrocracking are jet fuel and diesel, but low-sulfur naphtha fractions and LPG are also produced. All these products have a very low content of sulfur and other contaminants.
Is hydrocracking endothermic or exothermic?
Hydrocracking reactions are the main sources of hydrocarbons (C1, C2, C3 and C4). The reactions are highly exothermic and consume high amounts of hydrogen. Cracking results in the loss of the reformate yield.
How does a hydrotreater work?
During hydrotreating, crude oil cuts are selectively reacted with hydrogen in the presence of a catalyst at relatively high temperatures and moderate pressures. The process converts undesirable aromatics, olefins, nitrogen, metals, and organosulfur compounds into stabilized products.
What is hydrocracking catalyst?
Hydrocracking is replacing fluidised catalytic cracking as the refinery conversion process of choice. The performance of hydrocracking units is fundamentally dependent on the zeolite catalyst used to break down the heavier oil molecules.
Why is hydrocracking exothermic?
The aromatics rings themselves cannot be hydrocracked. They must first be saturated into naphthenes. Hydrocracking reactions release less heat because they are the sum of two reactions – the endothermic breaking of C–C bonds and the exothermic hydrogenation of the resulting olefins.
What are the primary differences between cracking and hydrocracking in a petroleum refinery?
The basis of catalytic cracking is carbon rejection, while hydrocracking is a hydrogen addition process. Catalyst cracking uses an acid catalyst, while hydrocracking uses a metal catalyst on acid support. Another differnce is that catalyst cracking is an endothermic process while hydrocracking is an exothermic process.
What is petroleum desulfurization?
Desulfurization is the process of removing sulfur from crude oil (or its fractions). It prevents contamination and also improves the efficiency of petroleum. Desulfurization removes elemental sulfur and its compounds from solids, liquids and gases.
Which reactor is used for hydrodesulfurization?
bed reactors
Hydrodesulphurization (HDS) of gasoils is conventionally carried out in the petroleum industry in co-current trickle bed reactors.