FQE Chemicals Blog

Many of the process streams in a refinery contain unsaturated hydrocarbons, sulfur compounds, nitrogen compounds and other materials (metals) that interfere with some of the refining processes. Hydrotreating is a catalytic process that makes use of by-product hydrogen from the catalytic reforming process, to saturate hydrocarbons (change a carbon-to carbon double bond to a carbon-to carbon single bond) by adding a hydrogen atom to each of the two carbon atoms. In doing so, the process removes sulfur, nitrogen and metals from a wide variety of process streams. In general, each of the major streams coming off the atmospheric tower will have a hydrotreating unit.

Upon leaving the desalter, the crude oil will go to a crude processing unit where the first actual separations will take place. The feed charge will pass through the preheat bundles, generally on the shellside, where it will pick-up heat from an already processed stream. These bundles are where one type of refinery coke is formed. The temperatures are not high enough to form true carbon, but the deposit will still be extremely hard to remove chemically.

In previous discussions we have discussed this problem and also identified that technology has advanced so that very effective chemical cleaning of these “coke” (really asphaltene) deposits can be successfully accomplished in-place while off-line. Quite frankly, better outcomes are possible if operations would chemically clean these exchangers more often and not wait until the exchangers are nearly plugged solid.

As we have spoken about decontamination of the crude distillation unit we have discussed tank cleaning operations, how to address troublesome desalters and general degassing issues. Throughout these talks, there has been a common theme in the background. And, what is that? More often than not, the refiner is plagued with fouling from heavy organic deposits. Typically, these compounds are asphaltenes, waxes, and resins. Why is this so?

Part 5 in the series on how the chemical industry is solving challenges in the industrial sector.

Part 4 in the series on how the chemical industry is solving challenges in the industrial sector.

Part 3 in the series on how the chemical industry is solving challenges in the industrial sector.

Part 2 in the series on how the chemical industry is solving challenges in the industrial sector.

 
“Degassing,” a term frequently used in the petroleum processing and production industries, is the process of evacuating hazardous vapors from the interior of processing vessels and piping.

These hazardous vapors are typically volatilized hydrocarbon gases and hydrogen sulfide, among others. The process of degassing does not include the removal of residual organic or inorganic solids or scales—only vapors.

Part 1 in the series on how the chemical industry is solving challenges in the industrial sector. Follow along as we explore how customized chemicals increase the efficiency, safety and financial performance of refinery operations.