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Blog: The Story of Energy Efficiency Improvements at Port Neches
1:38 PM MDT | April 30, 2010 | By JOHN PROWS
John Prows, v.p./manufacturing excellence at Huntsman's performance products division, said the following at CW's webcast, Reduce Energy Costs with Advanced Process Design, on Tuesday. The recording of the webcast is available by clicking here and clicking the 'register now' button. Prows's coments have been edited for clarity.
Back in 2005, our divisional president was asking how many of us believe that oil is going to be over $100/bbl by year-end. We all originally looked at him cross-eyed and thought "boy, that's a steep hike." I think oil was $45 at the time but it went well above that three times before it peaked. So, we started our energy management program in 2006 with an initial target of 10% energy intensity reduction, and a 5-year goal of a 25% reduction. Last year we were well on track to achieve that. I have to say that Aspen has been a very key partner of ours in achieving the reduction we had at Port Neches. One of the things we were looking at doing initially in the ethylene plant was understanding the technology we had, what we could change and couldn't change, and how that would affect energy optimization. The person running the plant at the time had proposed six very expensive capital projects related to that. We decided to hire Aspen to tell us where new technology might benefit us versus what we might be able to do ourselves without such a big capital spend.
Huntsman achieved millions per year in cost savings at its Port
I took the original proposals to my boss and he pretty much laughed me out of his office. He said, "hey, I've got a fixed cost drill going on, we are trying to reduce fixed costs and here you are asking for a pretty good chunk of money to go do a study to do first principles modeling." But I threw it right back to him and said, "you ask me the question all the time, what is theoretical best and the best way I know to find out is to do a chemical engineering model and also do some external benchmarking and Aspen is in the best position to do that. We're short of engineering help we've got engineers trying to run units and they don't have time go do models. Aspen can do that more efficiently."
I still remember the day he approved the work we did on our big propylene oxide unit. He wagged his finger in my face when he gave me the money and said "there better be a payback on this." I was in there hounding him because I had an engineer with 45 years of experience telling me that we needed to do this project.
The great news is that when Rian Reyneke came on board and our teams started digging in there were immediately discussions about whether the meters were right. Rian was trying to close some of the balances around some of the towers and they would not close. So our guys were coming to Rian, an experienced chemical engineer who knows the Aspen tools, and telling him that he was wrong. Eventually, Rian said "John, I don't think I'm wrong, I think there's something wrong with the metering." He told me, "you know, John, if this tower was really using as much energy as the meters say, you'd be cracking molecules in there and I don't think that's what this tower was designed to do." I laughed and said I doubt it too.
I asked the operations team to go back and see why this tower is appearing to use so much energy. One of the things they found was that there was a bad meter, it was very far off, it was telling them that this tower was using a huge amount of energy. It showed them there was a valve problem and that we could be using hot quench water to do the boil-up on this tower, but because this valve had been closed and insulated over no one knew that the quench water was actually off when the meter was showing flow. This tower was pulling steam to do that distillation work when gas was at 8 or 9 dollars per million BTUs. We fixed it, and just on that savings alone I was able to go to my boss within a month's time and say, "you got your money back already."
The credibility from that helped us to identify another 26 bad meters on that old unit. When new took the unit down a year later we went after those meters. One thing is for sure - you can't improve something if you can't measure it. Once we improved the meters and got it right, we identified other problems. The teams were able to work on a series of projects Aspen had identified and one by one knock them off. There was another big win on tower pressure control. We asked why the unit was running high pressures when it can run lower pressures and conserve energy and the feedpoints were available to do that. The people working on the unit said, "that’s what our operating procedures from the 1960s tell us to do." We were able to change that in a couple of days and it was another huge savings.
Certainly from an energy saving standpoint I cannot be more pleased with what this team has done in working with Aspen collaboratively to achieve some very significant savings. The question was asked, are we where we want to be, no, there's still a lot more upside. But have we made major improvements in our energy burn, yes, to the tune of about 4 trillion BTUs across our division and we still have a lot of room for improvement.
For more information, click here to listen to the FREE recording of the webcast.