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  1. bchoate

    Ammonia Blending, Storage, Shipping - Rego Valves

    bchoate Hydrostatic relief devices (such as Rego parts) are used to relieve pressure from thermal expansion. Anywhere that a line portion can be block in by valves has to be protected by a hydrostatic relief device. A small liquid release is sufficient to relieve pressure resulting in small...
  2. bchoate

    Anhydrous Ammonia vents

    BChoate OSHA requirements in 29 CFR 1910.111 cover ammonia systems. A requirement you mention, thermal relief for liquid ammonia trapped between two valves, is part of 1910.111 (which is ANSI K61.1 in CFR form). You didn't mention if the liquid ammonia is under pressure or is atmospheric at...
  3. bchoate

    Calculating amount of steam required

    abamin Glad you were amused as well. The problem looked like a student doing homework to which we do not respond. Based on the question as initially posted, consider the following: 1. 1,000 gal. * 8.33 lb/gal = 8,330 lbs H2O 2. Q =m*Cp*delta T = 8,330 lb * 1 BTU/lb/F * 90 F = 749,700...
  4. bchoate

    Calculating amount of steam required

    abamin Your question is about rather elementary concepts. It would seem that you should be able to do this. I'll give you a hint. What is the duty required? (heating up the water): sensible heat Q = m*cp*(T2 - T1) Where does the heat come from? (steam) latent heat of condensing 30 psig...
  5. bchoate

    Inhibited Monoethylene glycol

    oxidation It is almost impossible to achieve an accurate pH measurement of nearly pure ethylene glycol. pH meters are susceptible to errors and instability when used in organic liquids. A simplistic concept of pH is that of a dimensionless measure of the hydrogen ion concentration in...
  6. bchoate

    Determining choked flow

    n3scz Beychok's thread FAQ378-1201 referenced by zdas04 gives a full explanation of 'choked' flow. If the P(1)/P(2) ratio for an orifice is in the range 1.7 - 2.1 for most gases, the conditions are there for 'choked' flow. Since the velocity through the orifice at choked flow is fixed at Ma 1...
  7. bchoate

    benzene condensation problem

    Pepijn76 OK. Stream you are talking about is the 100C benzene/steam from regeneration. When you reduce condenser process outlet T you get the scenario you described. The azeotrope explains the behaviour. The water/benzene azeotrope boils at 69.2 C. As the feed moves through the condenser...
  8. bchoate

    benzene condensation problem

    Pepijn76 I am lost trying to follow where you are in your process but I can give you a piece of information that may help. Benzene and water form an azeotrope that boils lower than benzene or water. The azeotrope boils at 64.9 C with 7.5% water in the azeotrope. This azeotrope has been used...
  9. bchoate

    Vortex Breaker

    toabhijeet[b] Post above is very general and has more unsaid than said. I am going to make some assumptions and give some general information. Assumption: Tank with bottom or lower side drain; feeds pump or some other vessel. Vortex forms in liquid during drain if there is insufficient liquid...
  10. bchoate

    benzene condensation problem

    Pepij This is explained as follows; A condensible vapour in air (or other gas) condenses when the temperature of the mixture is decreased to or below the temperature at which the gas is saturated with the vapor (dew point). By increasing the makeup air, the mole fraction of benzene in the...
  11. bchoate

    Sodium Bisulfite production

    KrilleRen The plant that I worked in prepared a low concentration (<15%) solution of sodium bisulfite. Details are proprietary. Concern with static mixer system is amount of heat generated by dissolution and reaction of SO2. That could be a problem or a heat exchanger with mixing element...
  12. bchoate

    Sodium Bisulfite production

    KrilleRen I would like to offer a caveat or two regarding this process. I have worked for a company that produces sodium bisulfite on site for a proprietary use on site. That process was simple. Liquid sulfur dioxide was mixed with a sodium carbonate or sodum bicaronate solution using a...
  13. bchoate

    VSM Standards compliance

    Francisrunner VSM standards are Swiss if my research is correct. A copy of the standards can be obtained from the following reference for about 100 CHF (Swiss). []http://www.snv.ch/en/shop/products/vsm_guide_to_standards/[] The next reference shows an application of a portion of the standard...
  14. bchoate

    Optional for MIL-PRF-87937 Cleaner

    Romanos I am listing some materials and suppliers that claim to meet the requirements of MIL-PRF-87937. You can check the claims and acceptability with your client. ALK-660 -- manufacturer claims it conforms to the MIL-PRF-87937 Type II spec. []http://www.eldoradochem.com/pb/ALK-660-PB.pdf[]...
  15. bchoate

    pH Values of various acids

    micalbrch 25362 thanks for your comments. The info I posted was a simplified version because I suspected micalbrch was not a chemical engineer and maybe not totally comfortable with info for the posted discussion. It did seem that the Sensorex link did not completely answer his question...
  16. bchoate

    pH Values of various acids

    micalbrch Let's see what you are after. The sensorex app requires molar (mole solute/liter solution) concentrations. The acids of interest include both strong (sulfuric, hydrochloric, and nitric) and a weak acid (phosphoric) Assuming that you know the definition of pH: pH = -log(H3O+) and...
  17. bchoate

    Pressure increase closed container

    marantinj I agree with zdas04's post that your post is suspicious. The liquid occupies about 10% of the container volume. If the container is filled with air at ambient conditions prior to adding the cold liquid, the number of moles of air is insignificant. There are several unknowns and a...
  18. bchoate

    Difference gas vs vapour

    nlkw mbeychok's comments are not disputed. At a number of levels "vapor" and "gas" are synonyms and engineers loosely use the terms interchangeably. They both refer to a phase of matter not solid or liquid as stated by more than one responder. However, some differences are described at...
  19. bchoate

    Difference gas vs vapour

    nickyloke A variety of comments have been offered in this discussion. Consider the following observations: Conventionally, "vapor" and "gas" are often used interchangeably. But there are differences when one begins to critically look at the two. "Vapor" and "gas" both refer to a physical...
  20. bchoate

    MIL-STD-810 Explosion Proof for Class 1 Div. 1?

    PW2006 Note: You can probably use the instrument. MIL-STD-810f Method 511.4 provides two testing protocols. The first tests whether an instrument can generate sufficient spark energy or spot temperatures to ignite a test mixture. This is a measure of intrinsic safety for the instrument...

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