Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  1. cheute79

    Leaking PSVs

    Does the client have the records that document the relief scenario on which the current PSV was selected? The sizing should be based upon a specific scenario, that documents conditions. Asking to verify sizing is just spending time and money. One can readily find a scenario, which might not...
  2. cheute79

    PSV Change Over Schedule

    I am aware of only the IIAR (ammonia industry) standard that provides clear guidance. As I recall, it requires annual or upon a relief incident, whichever comes first. I've never found any other code, rule or standard for any other industry or general use.
  3. cheute79

    Flame arrestors.. what standard determines if they are required.. ?

    There are several standards, but few codes (a standard being a recommended or best practice, and a code being mandatory or law). The only code I know of applies to US facilities that collect vapors from ships or barges (Coast Guard rule). Standards include ANSI (UL 525), API RP2210 and...
  4. cheute79

    How to size soild particle pipe line velocity

    Aside from calculating velocities, also consider the impacts (a pun) of pneumatic transport methods. Dilute phase will tend to pulverize the solids more than dense phase, dense phase can blind if the solids are even the least bit sticky, dilute phase will induce a lot more erosion in the pipe...
  5. cheute79

    Sump Agitation

    I have no literature to offer, but perhaps a water treatment equipment vendor will. I suggest, however, that you know your sludge: what it the loading of sludge, on average, in the sump? (wt% solids, both wet and dry - this'll get you a feeling for waters of hydration), settling time...
  6. cheute79

    How to naming the interlock number in P&ID

    There is no univeral or widely accepted device or equipment or logic tagging system or convention. ISA has some suggested standards. All larger companies have developed some sort of standard so that their controls and process engineers can communicate and work together and with operations and...
  7. cheute79

    How to corelate Leak frequency for SIL suggestions

    SILs are not absolute numbers that apply in all situations. If you are a hydrogen extraction or production facility, not enclosed or very well ventilated, 10 000 lb/hr might be OK, since it might be a leak of less than 1% of process, and tends to "leak" straight up and not accumulate. If the...
  8. cheute79

    How to calculate Vapor Molecular Weight

    I suppose knowing the MW for the fatty acid might give you some peace of mind for estimating emissions, but if you don't know the formula, the name of the compound, or anything more than that it is a fatty acid, perhaps look up a few fatty acids, take an average, or assume a "highest case"...
  9. cheute79

    Rejected DI water

    What do you mean by rejected DI water? Do you mean the "blowdown" or the stuff that hasn't been deionized? That is concentrated in whatever was in the incoming water, including, potentially, chlorides, nitrates, and others. If you mean DI water, but somehow past its "expiration date" or...
  10. cheute79

    Secondary Containment for Chemical Delivery Vehicle Areas

    Om the US, it is a direct code requirement in some states (NY, for instance). In others, as suggested by JB and Latexman, it is groundwater protection that almost always ends up being the motivator. This can, again, be a direct requirement in your NPDES or GW permit, or it can be inferred by...
  11. cheute79

    Disposal/Conversion of Waste Hydrogen Gas

    Years ago I did a lot of work in support of TMI-II cleanup, and one of the tasks was to look into recombiners for waste shipping canisters. I did extensive testing on recombiners over several years. There is nothing magical about them. You could probably make some yourself, or perhaps talk a...
  12. cheute79

    PSM Training question

    The code is intentionally vague, but many parts are clear. As the owner, you (your employer) must assure that ALL operators and maintenance are adequately trained. Therefore, you can train them and maintain the records, or you can ask (and periodically audit to assure) that your contractor...
  13. cheute79

    Costing Index for January 2011

    for Chemical Engineering Plant cost index, sign up for a limited subscription to Chemical Engineering magazine. Each month there is an updated summary on the back page (they used to teach that in school). For an estimate of the cost of a tower, it depends on what you want for "accuracy". as a...
  14. cheute79

    Rule of thumb for tall thin tanks..economic limits or pratical limits

    Economic and practical have a lot of considerations. If you MUST have the increase in volume, but you are stuck with the footprint, your limit is probably closer to what height restrictions do you have at the location (a roof, or by air permit, or building permit, for instance), or what can be...
  15. cheute79

    Determine NPSHa of centrifugal pump

    The minimum NPSH required (by the pump) might define the LLA. Else why the LLA?
  16. cheute79

    angular velocity calculation in stirred tank

    Good luck on this. Modeling and scale-up of mixing systems is very much an art, and what you are asking for may well be a multi-variable partial differential, and based on many assumptions. There are factors to consider that you have not mentioned, such as rheology of the fluid, presence of...
  17. cheute79

    Maintaining Constant 28 C temperature in anaerobic digester

    I suspect that you also have need to maintain relative humidity, which will be harder in winter. Your target temperature is 28°, and your dew point is probably 23° to 25°. Air coming in at 7° will have a dew point less than that. If you have a design to spray excess water on packing and raise...
  18. cheute79

    C02 Removal from Bio gas stream

    This is a bit of a different approach, but your CO2 concentration is in the same ballpark as off-gas from a brewery or ethanol plant. They use a scrubber to remove and collect (and sell, if there is enough local demand by the soda pop industry) the CO2. The concentration is then low enough...
  19. cheute79

    Shell and tube heat exchanger - tube length

    Dan: This is a bit outside my expertise, but when I have had custom shell and tube exchangers made, I have always found it easier, faster, cheaper (the big 3 drivers) to have the shell of standard pipe sizes, so for any shell of 12 to 36 inches, the "standard" internal diameters would be STD...
  20. cheute79

    Piping design: pipe flow v.s. open channel flow ?

    EngReno, my understanding of what you have described is essentially plumbing and waste flow. I can't see how the only air escape is at the point of collection, and still get channel flow. Head pressure can drive the flow, but even then the flow will be slug flow, not true channel flow, as the...

Part and Inventory Search

Back
Top