1- Means of Hydrotreating.
2-Pupose of hydrtreating
3- Applications of Hydrotreating.
5-Hydrotreating process for distillate.
6- Hydrotreating process for smoke point
4. Purpose of hydrotreating
• Remove hetero atoms and saturated carbon-
carbon bond sulfur , nitrogen, oxygen, and
metal removed olefinic and aromatic bond
• Reduce average molecular weight & product
higher yields of fuel production.
• Minimal cracking
• Minimal conversion- 10% to 20 % typical
• Reforming catalytic cracking , hydrocracking.
5. Applications of Hydrotreating
Various application of hydrotreating process are;
1 - Reduction of sulphur in the feed to the catalytic reformer.
2 – Desulphurization of naphtha, kerosene, gas oil and fuel oils.
3 – Improvement of colour, odour , oxidation stability of
lubricating oil base stocks and waxes.
4 – Mild hydrogenation of aromatics into naphthenes in streams
like high aromatics kerosene's and gas oils to improve smoke
point and cetane number , respectively.
5 – Hydrogenation of olefinic streams produced from thermal
10. Hydrotreating process for distillate.
To remove contaminants (sulfur, nitrogen, metals)
and saturate olefins and aromatics to produce a clean
product for further processing or finished product
Primary Process Technique
Hydrogenation occurs in a fixed catalyst bed to
improve H/C ratios and to remove sulfur, nitrogen,
11. Process description,
• Feedstock along with recycle hydrogen-rich gas
stream is preheated to the desired temperature and
the mixture is then passed to a fixed-bed reactor.
• The reactor effluent after cooling go to a high-
pressure separator where hydrogen-rich gas is
separated and recycled back to the reactor.
• The liquid product from high-pressure separator
goes to low-pressure separator where light gases
are stripped off.
• The liquid product from the low-pressure separator
• Three general catalyst used in hydrotreating are Co-
Mo, Ni-Mo, Ni-Co.
• These catalysts usually have a alumina or zeolite
support and are sulfide before use by treatment with
H2S in the presence of hydrogen.
Typical operating condition
For hydrodesulphurization of gas oil, the typicl operating
condition are under:
• Reactor temperature, 0C 360-390
• Pressure (separator drum), Kg/cm2 40
• Space velocity, m3/h feed at 150 C/m3 catalyst 2.1
• Recycle gas rate, Nm3 pure H2 /m3of liquid feed 200
14. Hydrotreating process for smoke point
• This process converts aromatics in kerosine into naphthenes and
thus enhances its smoke point / luminometer number.
• Desulphurized straight – run or hydrocrcked kerosine with a
sulphur content of 1-5 ppm together with hydrogen-reach gas is
charged to a semi-adiabatic reactor containing a noble metal on a
• After heat exchanger with reactor feed , the reactor product is
separated at high pressure in a hydrogen rich gas and a liquid.
• The hydrogen – rich gas is recycled back to the reactor.
• A part of the high – pressure separator liquid is used as quench oil
to restrict the temperature rise across the reactor.
• The remaining liquid product is a sent to a low – pressure
separator is sent to a stripper for the removal of dessolved gases
and light ends.
15. Typical operating condition
• Reactor pressure, kg/cm3g 50-70
• Reactor temperature, 0c 260-315
• Space velocity, ton/(m3 .h) 2.5-3.5
• Total gas rate, Nm3/ton 200-300