Ingenious ‘Top Divided Wall Column’ a First in the world at BPCL Mumbai Refinery
16 Nov 2017 | BPCL
The Revolution is in Full Swing
“We do not merely want to be the best of the best.
We want to be the only ones who do what we do.”
A brilliant innovation at Mumbai Refinery by Mrs. K. Shreya, Mr. P.A. Shanware and their team which resulted in making India, the first in the history of refining, to produce stringent quality hexane as a byproduct along with isomerate – a motor spirit blend component - from its Isomerization unit. This was done by delving into an unchartered territory. This Isomerization unit has the world’s first top divided wall column. All this, in response to the clarion call given by our Hon’ble Prime Minister, Shri Narendra Modi to the youth of our nation to use technology and opt for innovation.
Semi regeneration reformer at BPCL Mumbai Refinery was being revamped into an isomerization unit to take India on the road of total Bharat Stage (BS) IV motor spirit sufficiency. In a constant endeavor to disrupt the norm, it was thought to co-produce hexane from the unit along with motor spirit blend component, isomerate. As hexane has always been produced by the solvent extraction process, this was unchartered territory.
This revamped isomerization unit is inclusive of a divided wall column. Mumbai Refinery chose to incorporate a divided wall column in the design of the unit, in line with its aptitude of ‘the fore-runner’ in the Industry. The high energy saving potential, 27%, as compared to a multi column system gave the final push in this decision. This is also in line with our requirement of being a refinery in ‘quartile one’.
In addition, a divided wall column reduces plot area requirement - four columns in series vs single column installation – area which can be utilized for setting up other projects in the refinery.
Isomerization unit, licensed by M/s GTC Technology, LLC was commissioned at Mumbai Refinery in March 2017. Ever since, hexane of world class specification is being co-produced from the unit. This isomerization unit has modified the product slate of the refinery by moving from production of ‘food grade’ hexane to ‘pharmaceutical’ and ‘polymer’ grade hexane thereby increasing BPCL’s market share.
Hexane, of food grade quality, was a seasonal product with demand picking up during the festival season. With migration to the ‘pharmaceutical’ and ‘polymer’ grade, there would be no lean period for hexane.
This project has resulted in a huge monetary saving. 27% decrease in reboiler duty due to use of divided wall column along with change from medium pressure steam reboiler to fired heater reboiler accounts for a saving of more than ₹ 63 crores per annum. Also production of hexane from the isomerization unit has reduced its variable operating cost, by ₹ 32 crores per annum, as compared to a solvent extraction unit. All in all, the savings are to the tune of ₹ 95 crores per annum translating into 14.4 cents per barrel of crude processed in the refinery. Over and above, due to change in refinery product slate to pharmaceutical and polymer grade hexane, the exports into the country would reduce thereby giving a thrust to the ‘Make In India’ campaign launched by our Hon’ble Prime Minister.