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What are the optimal routes to valorisation of olefins-rich FCC unit and coker unit off-gas?
Replies: 3
How to confirm the run away reactions in Diesel and Vaccum Gas Oil hydrotreater units reactors? Is it localized phenomena at particular location or gets spread on wide area of the catalyst?
As the 1st bed hydrotreater bed exotherm for our unit already stays at above 40degC during normal operation, I would like to understand how to confirm the run away phenomenon and take necessary actions like actuation of EDPS. Kindly guide.
Replies: 2
In Diesel and VGO hydrotreaters, after feed pump failure, feed introduction is advised to be done within 15minutes, in case feed introduction is not done in 15minutes, it is advised to take normal shutdown by cooling of the reactor. What's wrong in feed introduction after 15minutes at high temperature?
Diesel hydrotreater feed introduction to Reactor is designed to be done at 180 to 200 DegC. Is there any issue, if feed introduction is done at 240degC or 260degC during Normal startup (Assuming HP Loop contains above Minimum prescribed H2S 2000 ppm).
It is well understood that the Mimium Pressurization Temperature is the temperature below which the steel is assumed to be brittle due to H2 Embrittlement in hydrotreating units.
How to understand conceptually, why beyond MPT value, H2 embrittlement is not an issue or reactor is not suspectible to loss of ductility, eventhough pressure after MPT value will be higher than before. Can someone please guide me?
Replies: 1
What measures or techniques do you employ to optimise the cooling of coke bed in drum and mitigate the occurrence of hot-spots? If you are performing pressurised quenching, what specific pressure levels do you maintain within the drum during the initial water quench ramp?
Replies: 0
What is the basis for maintaining minimum wetting rates in vacuum column (whether based on vacuum charge or design condition?) What will happen if minimum wetting rates are not adhering to?
What is the impact in the product quality if circulating refluxes return temperatures are not maintaining at design temperatures? Is it wise to reduce heat recovery in pre heat network for maintaining design pump around return temp at the expense of pre heat?
What is the expected volumetric efficiency in the diesel product treating only SRGO? (It is understood that it is less than 103.4% due to the decrease in the content of aromatics and olefins)
What is the best solvent to be used in a carbon capture train of syngas placed between the HTS and PSA unit?
We have loaded the catalyst (IP- 632) of our Isomerization Unit. So, what procedures must be taken before Startup? And what are the most important instructions to be followed?
What are the optimal unit configurations and combinations (e.g., FCC/hydrocracking) for increasing high-margins products, while reducing low-value streams (e.g., HSFO & LSFO)?
Considering the growing interest in maximising renewable and biomass feeds (including Fischer-Tropsch liquids) through the FCC, what are the most noticeable options you see refiners adopting beyond 2030? To what extent can renewable feed pretreatment be simplified (if at all)?
Replies: 5
To what extent do you see the deployment of digital approaches to maintain and operate facilities while leveraging artificial intelligence (AI) in the restructured operations of the petrochemical industry?
Replies: 6
Regional shifts in higher refinery capacity seem to correspond with the need for more intensive water treatment programmes involving wastewater recycle processes while protecting heat exchangers and linked assets from fouling and corrosion. At what level of investment have you seen refinery operators commit to plant water quality while reducing its consumption?
Changes in feedstocks processed through hydrotreating and hydrocracking reactors may sometimes lead to lower efficiency, such as thermal maldistribution problems and reduced cycle length. Can you report any recent cases, such as distillate hydrotreaters challenged with meeting T95 diesel specifications, where conversion problems were resolved that can be duplicated with other hydrotreating units facing similar challenges?
Considering market shifts favouring petrochemicals (for example, chemical-grade propylene), what are the optimal unit configurations and combinations, such as FCC/hydrocracking, for increasing high-margin products while reducing low-value streams, such as high sulphur fuel oil (HSFO) and low sulphur fuel oil (LSFO)?
What are the most attractive long-term options for incorporating autothermal reforming (ATR) and/or partial oxidation (POX) to produce blue hydrogen at near-zero CO2 emissions? Or can CO2 emissions from SMR units be further reduced?
Considering the range of petrochemicals used crosswise for preparing a wide range of marketable products, including textiles, detergents, adhesives, antifreeze, solvents, and pharmaceuticals, what state-of-the-art catalysts are emerging for production of petrochemicals such as styrene, polymers, and aromatics?
What are some of the optimal strategies for processing (or co-processing) second- and third-generation renewable feedstocks?
In building the petrochemical value chain, how much further can we see the FCC unit being used to increase olefins production with the wide range of feedstocks currently available, including waste plastics-derived pyrolysis oil?
Replies: 4
What hydrocracking reactor catalysts are demonstrating optimal mid-distillate selectivity, better yield structures, and more efficient use of hydrogen? In combination, which of these catalyst systems seems to be the most flexible in adjusting to feed quality variations and heavy feeds such as DAO and HVGO molecules?
Besides improved catalyst systems, what advances in reactor internals are improving efficiency and throughput while also mitigating the effect of fouling and catalyst poisons?
Maximising cycle duration of hydroprocessing units has always been important to refiners, but what other step-out gains can we see from catalyst developments in terms of volume swell, PNA saturation, and HDN activity while achieving high HDS performance?
Unloading contractor encountered fire due to vacuum unloading of HDS reactor. Unloading a fixed bed hydrotreater reactor is classically done under Nitrogen atmosphere in order to avoid any fire due to deposit FeS. And FeS in nearly inavoidable in older units due to corrosion in the upstream equipment. Normally avoiding any fire is ensured by putting the reactor and the unloading nozzles until the drum dedicated to the unloaded catalyst under N2. Sometimes it is necessary to unload the reactor from the top by vacuum (e.g. sampling of spent catalyst is needed, or there are baskets on the distributor tray).
In that case, how the unloading company can avoid that the catalyst comes in contact with air? Can their vacuum facility be operated under N2?
With global hydrocracking unit capacity and feedstock diversity increasing, what strategies are available to prevent reactor runaway and increase overall unit safety?
I am in Hydrotreater, I want to know how much stripping steam is required in stripper, during startup we use excess steam in stripper to achieve diesel doctor test negative, is it beneficial or adversely affect steam stripping?
We are experiencing frequent amine carry-over from our high pressure amine absorber. What are the possible causes and solutions?
In catalytic reforming Process: - increasing the initial boiling point leads to increasing in hydrogen production. Any Explanation ? - How can we increase the purity of the hydrogen (recycle gas) ? - What is the maximum allowable moisture (ppm) in the feed (Heavy Naphtha) ?
Can we use biofeedstocks without co-processing them with conventional crudes to produce drop-in fuels?
What are some of the most effective compressor performance strategies for improving the mean time between failure (MTBF)?
What heat exchanger fouling prediction frameworks do you see benefiting refinery and petrochemical operations?
What optimal hydrocracking catalysts and operating strategies are needed to co-hydroprocess waste oils with VGO?
With the enormous potential for reducing the refinery carbon footprint by increasing direct fired heater efficiency, what successful cases provide an example of increased efficiency and reduced emissions?
Does sulphiding of hydrotreater CoMo and NiMo catalyst possible with Straight run feed containing Sulphur instead of DMDS?
If so, how exactly Sulphur containing Straight run feed can sulfide the catalyst?
As in the later case, DMDS decompose at the operating temperature of above 190degC and provides required H2S for initiation of sulphiding process, but how does Sulphur containing straight run feed can provide H2S?
We’ve increased the opportunity crude content of our feed and are experiencing high calcium issues. How can we best address this?
We have a problem in our Desalter. When we turn on the electric transformers, the electricity feeder trips off immediately several times. One of the transformers is damaged. The desalter contains only Crude Oil (Not mixed with water) What are the causes?
Replies: 8