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Recent content by Mutt

  1. Mutt

    Excel - Equating two equations

    You can use a solver function to maximise P, varying P and e such that the calculated top and bottom limits equal the set maximum values in the solver constraints. That gives the extreme values of P and e, not necessarily the optimum though....the solver solution then gives P as 4189263 and...
  2. Mutt

    Excel question

    You could also add in another column with AND function : So for cells below, in column E you could have expression in cell E5 something like =AND(D5=40,ABS(D6-40)<0.1,ABS(D7-40)<0.1,SUM($E$4:E4)=0)*C5 The answer is found by summing all column E or looking for max in column E. C D E F G H 4...
  3. Mutt

    Melt Facility

    I have some limited experience of melting scrap wax and found that heating the wax chunks in a vessel to be very slow. Especially if use low pressure steam so that you don't brown (crack and/or oxidise) the wax. Best method was to have a rack of pipes with steam of correct grade inside them...
  4. Mutt

    Automation of excess steam condenser unit.

    Maybe I don't fully understand the system but I would have had the PCV2 upstream of the air coolers. PCV1 would have a setpoint of 60psig and PCV2 slightly higher, say 67psig such that when PCV2 is opening, PCV1 should be about closed. That way you minimise steam waste. You only condense the...
  5. Mutt

    Amount of heat required to produce 50 psig in pipe with water in it

    On simple calc basis using steam tables and ideal gas law....and metric :-) The pipe volume is 1.8 litres. Assume half filled with water, so vapour volume is 0.9litres. Heat system to a temperature T. The desired pressure in the system is 435kPAa. (app. 50 psig) The air volume, Va, is now...
  6. Mutt

    Pressure rise when filling sealed tanks

    You want the vapour composition at a fixed P and T. Use a flash vessel with a feed stream of the composition of the total mixture in your reactor at the T and P of the vessel. Say at a feed rate of 1 kg/s. Specify the flash vessel at the same T and P with a vapour and liquid stream offtake. Duty...
  7. Mutt

    Temperature shift catalyst reduction

    Considering that the vendor states a wide range space velocity of between 200 and 800/hr and you can use methane or nitrogen as the inert material and a temperature of 'between 330 and 350F' I don't think a less than 2% error in your flow mass rate will matter. I would suggest keeping the nm3/hr...
  8. Mutt

    GTL and North Slope Gas

    Used to be a lobby group looking at us that - haven't heard much lately. Most of the big GTL guys made proposals. Biggest concerns probably environmental - e.g. large human impact to support such facilities. Also out of curiosity (ignorance?) - aren't long distance liquid pipe lines quite...
  9. Mutt

    Formula updates when new worksheet is inserted

    You could define a function to go thru all worksheets, check category (input variable) and name (input variable) and sumup the required hours if both true. Simple example : if category on each project sheet is in A1 and employees names are listed in rows 3-100 in column A and their hours for...
  10. Mutt

    burner for hydrogen-rich fuel

    You will also need to check the burner design itself - hydrogen has very high flame speed and if current gas velocity ex the burner is too low, could get flame back inside the burner. Check Wobbe number, flame speed and capacity of new fuel mix against exising hardware's design burner triangle...
  11. Mutt

    Sorting combinations of letters and numbers

    One way but tedious : In an adajacent column use =""&A1 for each row. Range Value the new column Now sort new column and when asked select option sort numbers and numbers stored as text separately.
  12. Mutt

    formula help

    Just as an aside - I find with these multi conditional formulae it is far easier to debug if you quickly write a VBasic defined function to do the job.........plus no limit to number of levels.
  13. Mutt

    floating roof

    Here'a an extract from http://bulktransporter.com/mag/transportation_environmental_regulations_drive/ "Product true vapor pressure (TVP) is the single most critical design parameter when selecting the type of floating roof. Most current environmental regulations limit the product TVP to less...
  14. Mutt

    Converting ppm to mole%

    Excuse my question but why do you have to have the total sulphur in the crude, expressed as mol% H2S? Generally just want to know how much sulphur to remove and mass is just as good a basis. As Montemayor says, mole weights of crude are hard to come by as not used generally in designs.
  15. Mutt

    Absorption of ammonia gas by subcoled solution

    The 75kg/s seems high, how conc is the ammonia in the scrub water? If the liquid was pure water, could reduce to around 12kg/s, dropping column diameter by factor of 2 to 3.

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