Inspectioneering

Hydrotreater

Explore this topic

A Hydrotreater, or hydro-desulfurization (HDS) unit, is the process equipment used in petroleum refining to remove sulfur and nitrogen compounds from natural gas and other refined petroleum products like deisel, gasoline, and jet fuel. In petroleum refining, it is important to remove sulfur from the process stream in order to:

  1. Prevent sulfur from poisoning the noble metal catalysts in the subsequent catalytic reforming of the naphtha; and
  2. Reduce sulfur dioxide (SO2) emissions to meet more-stringent clean fuels specifications.

In the HDS process, the oil feedstock is first heated and combined with high-purity hydrogen gas. This mixture then enters a reactor filled with a catalyst, typically consisting of an alumina base impregnated with a metal (usually molybdenum or tungsten) and a co-catalyst (typically cobalt or nickel). These catalysts are chosen for their ability to facilitate the HDS process.

The hydrotreating reactor operates under high temperature and pressure conditions, typically between 572 - 752 ºF (300 - 400 ºC) and 440 - 1910 psi (30 - 130 bar). Under these conditions, the sulfur compounds in the oil react with hydrogen, forming hydrogen sulfide and yielding desulfurized hydrocarbons. In essence, sulfur is replaced by hydrogen in the hydrocarbon molecule through a process known as hydrogenolysis.

The mixture then exits the reactor and proceeds to a high-pressure gas separator, where the released hydrogen sulfide is removed from the hydrocarbon liquid. The liquid product is then typically directed to a stripping tower to remove any residual light hydrocarbons and hydrogen sulfide.

References

  1. https://www.aiche.org/resources/publications/cep/2021/october/overview-hydrotreating
  2. https://en.wikipedia.org/wiki/Hydrodesulfurization. 

Related Topics

Relevant Links

Topic Tools

Share this Topic

Contribute to Definition

We welcome updates to this Integripedia definition from the Inspectioneering community. Click the link below to submit any recommended changes for Inspectioneering's team of editors to review.

Contribute to Definition

Subscribe to Inspectioneering

Articles about Hydrotreater
March/April 2018 Inspectioneering Journal

Hot spots – localized areas of overheating in pressure equipment – can lead to deformation or even loss of process containment. It is important to understand the effects of elevated temperature caused by hot spots on the mechanical integrity of...

Online Article

Inspectioneering recently had the opportunity to chat with Barney Smith, Turnaround Manager at Aggreko, a global leader in power, heating, cooling, and oil-free compressor rental solutions. Our discussion focused on catalyst cooling during...

Authors: Jeremiah Wooten
Partner Content

The OmniScan™ X3 64 phased array and TFM flaw detector is equipped with enhanced phased capabilities and even faster TFM. The rugged and portable instrument features powerful 64-element probes with a 128-aperture TFM.

    News related to Hydrotreater

      Inspectioneering Journal

      Explore over 20 years of articles written by our team of subject matter experts.

      Company Directory

      Find relevant products, services, and technologies.

      Training Solutions

      Improve your skills in key mechanical integrity subjects.

      Case Studies

      Learn from the experience of others in the industry.

      Integripedia

      Inspectioneering's index of mechanical integrity topics – built by you.

      Industry News

      Stay up-to-date with the latest inspection and asset integrity management news.

      Blog

      Read short articles and insights authored by industry experts.

      Expert Interviews

      Inspectioneering's archive of interviews with industry subject matter experts.

      Event Calendar

      Find upcoming conferences, training sessions, online events, and more.

      Downloads

      Downloadable eBooks, Asset Intelligence Reports, checklists, white papers, and more.

      Videos & Webinars

      Watch educational and informative videos directly related to your profession.

      Acronyms

      Commonly used asset integrity management and inspection acronyms.