What Does Fluid Catalytic Cracking (FCC) Mean?
Fluid catalytic cracking (FCC) is a refining process of gas oil, which could not be distilled in an atmospheric tower, into lighter transportation fuel by reducing the molecules of the heavy oil by use of a catalyst, pressure and heat. The result of this process is to reduce the molecular structure of the heavy oil and also remove impurities or waxes that are readily adsorbed in them. This process aims to reduce the corrosion potential of heavy oils.
Corrosionpedia Explains Fluid Catalytic Cracking (FCC)
In this process the gas oil is preheated in the drums or storage and pumped to the riser or reactor-generator. The riser provides contact between the gas oil and the catalyst, which are atomized into the stripper. The steam present in the stripper along with controlled temperatures and pressures help to separate the spent catalyst from the vaporized or liquid hydrocarbons. The levels of the spent catalysts are maintained in the stripper and also the regenerator. The regenerator purifies the catalyst and channels it back to the riser to maintain the required amount in the fluid catalytic cracking unit.
The hydrocarbon vapors flow into the fractionator or main column, which condenses them into trays. The main column de-superheats the vapor and at the same time cools it as it washes away the catalyst present inside. Further distillation and refining cycles are applied to ensure that gasoline and diesel are produced. Fluid catalytic cracking is a fundamental complex process in the petroleum industry, as it converts high-boiling and low-value gas oil into valuable transportable oils.
Pipelines are mostly affected by gas oil or sand oil which is present in crude oil. Internal corrosion in the pipeline is caused by the presence of water and sediments. The lighter oil from fluid catalytic cracking does not allow water or sediments to settle and accumulate on the surface of the pipe floor; reduced amounts of water from this process have significantly helped in preventing corrosion.