Facilities for loading liquid hydrocarbons into tank cars, tank trucks, and marine vessels and barges are usually part of the refinery operations.
The most critical quality for lubricating-oil base stock is a high viscosity index, which provides for greater consistency under varying temperatures.
Vacuum towers are typically used to separate catalytic cracking feedstock from surplus residuum.
Distribution stations can be located in classified areas, providing that classification requirements are met.Stripping The removal (by steam-induced vaporization or flash evaporation) of the more volatile components from a cut or fraction.This is a closed system; however, the potential for fire exists should a leak or release of reformate gas or hydrogen occur.Visbreaking Viscosity breaking is a low-temperature cracking process used to reduce the viscosity or pour point of straight-run residuum.Because sat gas processes depend on the feedstock and product demand, each refinery uses different systems, usually absorption-fractionation or straight fractionation.The feedstock is first dried and then treated using a continuous countercurrent solvent treatment operation.Small emissions of carbon monoxide and hydrogen sulfide may occur during regeneration of catalyst.Failure of automatic controls, closed outlets, heat exchanger failure, etc.In addition, hydrotreating converts olefins and aromatics to saturated compounds.
Hydrocracking Description Hydrocracking is a two-stage process combining catalytic cracking and hydrogenation, wherein heavier feedstocks are cracked in the presence of hydrogen to produce more desirable products.
Desulfurization A chemical treatment to remove sulfur or sulfur compounds from hydrocarbons.The selection of specific processes and chemical agents depends on the nature of the feedstock being treated, the contaminants present, and the finished product requirements.Sweetening Processes that either remove obnoxious sulfur compounds (primarily hydrogen sulfide, mercaptans, and thiophens) from petroleum fractions or streams, or convert them, as in the case of mercaptans, to odorless disulfides to improve odor, color, and oxidation stability.Refinery off-gas is collected from process units and combined with natural gas and LPG in a fuel-gas balance drum.Coked catalyst may be either cooled below 120 F before it is dumped from the reactor, or dumped into containers that have been purged and inerted with nitrogen and then cooled before further handling.Many processes require hydrogen generation to provide for a continuous supply.Safe catalyst handling is very important.In order to further distill the residuum or topped crude from the atmospheric tower at higher temperatures, reduced pressure is required to prevent thermal cracking.These converted products are then subjected to various treatment and separation processes such as extraction, hydrotreating, and sweetening to remove undesirable constituents and improve product quality.Other corrosive substances are elemental sulfur and mercaptans.The charge is combined with a recycle stream within the riser, vaporized, and raised to reactor temperature (900- 1,000F) by the hot catalyst.Crude oils are usually grouped according to yield structure.In unsat gas plants handling FCC feedstock, the potential exists for corrosion from moist hydrogen sulfide and cyanides.Scrubbing Purification of a gas or liquid by washing it in a tower.