Q & A > Question Details
How to control IBP, FP and Ep for diesel, kerosene and light naphtha products?
14/03/2018 A: Emmanuel Aunde, Refining Company, lemma012@yahoo.com
For individual fractions, the pumparounds can be used to control the IBP of one and the FBP of the other. For instance, increasing the heat duty of the diesel pump around will increase the FBP of Kerosene but reduce the IBP of diesel. Changing the pressure will affect the whole system and may cost more money (charge heater duty) if we want the same quantity of total distillate. Moreover, it can be limited by cracking of the feedstock if our goal is to reduce IBP or FBP
11/10/2017 A: Jayaraj Jayam, Chennai Petroleum Corporation Limited, njayaraj@gmail.com
For the products from distillation tower, IBP can be controlled by manipulating column top temperature and by effective stripping of the products in the side draw strippers. Higher the steam rate will increase IBP by stripping off the lighterends.
Whereas FBP or EP can be manipulated by operating pressure and controlling the product draw rate. Higher the draw rate leads to higher end point.
10/10/2017 A: Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
Hydrotreaters normally have very little impact on the boiling range of the feeds. If you want to change the IBP or the EP of the product you need to change the feed fractionation in the upstream units that supply the feed to the unit. You can tweak the front end distillation by stripping harder or less hard in the product stripper but that normally won't have a large impact on the IBP.
09/10/2017 A: Ralph Ragsdale, Ragsdale Refining Courses, ralph.ragsdale@att.net
The short answer is by adjusting temperature and flow set points, with such set points reset by continuous analyzers if available. The EP of the heaviest product is controlled at the unit feed fractionator, the others at the columns downstream of the reactor section. Which instruments are used for a particular product spec depends on how the columns are instrumented. Pressure adjustments are not used for such control objectives.