Q & A > Question Details
We've been quoted a revamp time for our FCC unit of 120 days, which is prohibitive.
Has any refinery got experience of FCC revamp involving shutdown duration of 35-45 days?
26/06/2011 A: Sudhakara Babu Marpudi, Dangote Oil Refinery Company, m_sudhakarababu@yahoo.com
Sorting out shutdown job lists is very critical to the optimization of shutdown periods. Shutdown team can review and classify the jobs in the 5 major categories: 1. Jobs that can be taken up only during shutdown (systems that can not be isolated), 2. Jobs that can be done prior to shutdown by doing some modification (installation of isolation valves using line stopple) 3. Jobs that can be done after the shutdown (jobs related to down stream systems of storage tanks can wait till the plant is restarted and tanks are refilled) 4. Jobs that can be taken up online thru hot taps (jobs that require large shutdown time should be evaluated thoroughly to find out if the handing over time (hydrocarbon freeing / isolation by blinding etc.,) and efforts are reasonable considering the engineering / execution time and benefits of the revamp in that particular section and 5. Jobs that can be done in parallel during shutdown. Majority of the jobs can be taken out of the shutdown window if the cost benefit analysis of the jobs are carried out prior to shutdown. Risk assessment of the jobs plays a vital role in the reduction of shutdown time. Once the risk involved is known, the risk control measures can be put in place and jobs can be taken up while the plant is running. I am aware of a Refinery that has completed 32 no of welds on the shell of a running distillation column and several such jobs using hot tap / line stopple technologies using risk evaluation / mitigation processes to bring down the shutdown time. The otehr major contributor for shutdown is the handing over time. Chemical decontamination processes that guarantee the Zero LEL, Zero H2S, Zero Pyrophoric scales and Zero Benzene are very useful in reducing the handing over time. Technologies like pigging of furnaces allow the other jobs on the system to be done in parallel and hence reduce the shutdown time.
16/12/2010 A: Whitney Strickland, Calculated Controls, wstrickland@calculatedcontrols.com
My company AltairStrickland specializes in planning, managing and executing FCCU Revamps. We have done extensive 'heads off' revamps in as little as 25 days oil to oil.
05/12/2009 A: Saugata Palit, Intercat India Ltd, spalit@intercatinc.com
Though you have not mentioned the extent of revamp, a downtime of 120 days is very long. A typical revamping of FCC involving complete replacement of riser, RCSP, reactor and regen cyclones, regen air grids, reactor steam rings; replacement of column shed deck trays, WGC and MAB overhauling, etc, requires about 45 days.
03/07/2008 A: Ashraf Lakha, GTC Process Technology Ltd., ashraflakha@aol.com
You have not mentioned the extent of revamp but 120 days looks too much.
07/06/2008 A: Marcello Ferrara, ITW SrL, mferrara@itw.it
Our Online Cleaning and Degassing/Decontamination Technologies will help in dramatically reduce downtime before revamping operations.
The entire Unit can be delivered to maintenance clean and ready for hot work in as low as 48 hours.
30/05/2008 A: Mike Watson, Tube Tech International Ltd, mike.watson@tubetech.com
We have occasionally been asked to introduce faster tube cleaning and inspection technology for FCC exchangers during a revamp. This will certainly reduce cleaning times from ca. 18 days to around 3.
See: www.tubetech.com/heat-exchanger-cleaning-reduces-carbon-emmisions.asp which is an FCC case study on one of 4 FCC exchangers reduced from 3 days to 3 hours.
28/05/2008 A: Keng Chung, Well Resources Inc., kengchung@hotmail.com
Absolutely. Check with the FCC operators in China.