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A glossary of common terms and abbreviations used in the industry, with links to more in-depth articles on key words

R+M/2 -  a measure of gasoline octane that attempts to capture both the measure of road octane and motor octane in one number

Rabi (crude) - a light, sweet crude grade produced in Gabon

Rack -  the loading facility for tank trucks at a fuel terminal

Rack price - one of the key wholesale price points in the fuel supply chain

Rajasthan (crude) - a heavy, sweet crude grade produced in India

Ravva (crude) - a medium, sweet crude grade produced in India

RBOB - a common grade of gasoline produced by refiners in the US

RCC - (Resid cataliytic cracking) a variation of the FCC unit that is capable of taking heavier feedstock

Reactor - the part of a process unit where the chemical reaction takes place.  In most processes this is a vessel designed specifically to house the reaction

Reactor vessel -  the part of a process unit where the chemical reaction takes place.  In most processes this is a vessel designed specifically to house the reaction

Recycle - unconverted feedstock coming out of a conversion unit that is fed back into the unit as feed to increase yield (at the expense of fresh feed throughput)

Reduced crude - the heaviest of the distillation cuts out of the atmospheric distillation tower

Refinery fuel - the fuel used within a refinery to feed furnaces and provide heat to process units

Refinery gas - the lightest hydrocarbon stream produced from refinery process units. It is typically comprised of methane and ethane, but can also have some propane or butane in it

Refinery gate - pricing point for crude oil or refined product as it enters or exits the refinery, as opposed to somewhere further upstream or downstream

Refining - a processing plant that converts crude oil into a mix of different finished petroleum products

Reformate - the primary output of the catalytic reformer

Reformer -  refining process unit that upgrades low-octane heavy naphtha to make gasoline that meets minimum octane requirements

Reformulated gasoline - (RFG) the gasoline grade in the US required in many urban areas with poor air quality

Reid vapor pressure - (RVP) a measure of the volatility of a fuel, or the degree to which it vaporizes at a given temperature

Reliability - a measure of a refiner’s ability to keep the equipment available for use by maintaining mechanical integrity

Renewable diesel - (RD) a high-quality  diesel blendstock made from vegetable or waste oils through a process employing hydrotreating or hydrocracking

Renewable fuels - fuels that are not produced from oil and gas or other fossil resources.   Includes bio-fuels and e-fuels

Renewable fuels standard -  (RFS) the regulation in the US mandating the use of renewable fuels (e.g., ethanol and biodiesel) in domestic fuel

Renewable identification number - (RIN) the credits that the US EPA uses to track and enforce compliance with the renewable fuels mandates set by the RFS in the US

Renewable power - power generated from renewable sources such as wind, tides, solar or hydro.  

Renewable volume obligation - (RVO) the number of RINs that suppliers of gasoline and diesel in the US must acquire and submit under the RFS regulation

Research octane number -  (RON) one of the two primary measures of the octane value of gasoline or a gasoline blendstock

Resid - a very broad term used to refer to a range of intermediate streams and finished petroleum products

Resid cat cracking -  (RCC) a variation of the FCC unit that is capable of taking heavier feed. The RCC takes atmospheric resid and  VGO and cracks them using heat in the presence of a catalyst

Resid gasifier - A refinery process unit that converts resid into a gas that can be used as fuel

Resid hydrocracker - a refinery process unit that upgrades vacuum resid through cracking while injecting hydrogen

Resid hydrotreater -  (RHT) a refinery process unit that is used to lower the sulfur content of resid streams

Residual fuel oil - (RFO) one of the lowest-value petroleum products from a refinery. It is essentially a byproduct of producing the light products that are the primary focus of a refinery

Residue - a very broad term used to refer to a range of intermediate streams and finished petroleum products

Retail price -  the price that consumers actually see and pay when purchasing fuel at a retail station

RFG - (Reformulated gasoline) the gasoline grade in the US required in many urban areas with poor air quality

RFS - (Renewable fuels standard) the regulation in the US mandating the use of renewable fuels (e.g., ethanol and biodiesel) in domestic fuel

Rheniforming -  a type of reformer,  the refining process unit that upgrades low-octane heavy naphtha to make gasoline that meets minimum octane requirements

RIN - (Renewable identfication number) the credits that the US EPA uses to track and enforce compliance with the renewable fuels mandates set by the RFS in the US

Road oil - the densest liquid refined product produced by a refinery, but only stays liquid if stored and transported heated.  It becomes a solid if allowed to cool to normal ambient temperatures

RON - (Research octane number) one of the two primary measures of the octane value of gasoline or a gasoline blendstock

Roncador (crude) - a heavy, sour crude grade produced in Brazil

ROSE unit -  a refinery process unit that removes asphaltenes from vacuum resid, producing an asphalt product and a resid that can be used for base oil manufacturing or cracker feedstock

RVO - (Renewable volume obligation) the obligation a refiner or blender of gasoline and diesel in the US has to provide RINs as part of the Renewable Fuel Standard regulation

RVP - (Reid vapor pressure) a measure of the volatility of a fuel, or the degree to which it vaporizes at a given temperature

RVPI - (Vapor pressure index) index is used to calculate the vapor pressure of a gasoline blend comprised of blendstocks that have different vapor pressures