Search results for query: *

Our minimum design operating pressure is 350 kPag (51 psig). This is in our surge drum, which operates at 40C and 350-500 kPa (the pressure is controlled by supply and bleed pressure regulators on the vapour space, using natural gas to blanket the vessel). The hot glycol headers are on the...

Hi, Andrew The maximum design bulk process temperature the glycol will see is 140C, in one heat exchanger. This exchanger is in parallel with several other exchangers, all operating at lower temperatures. The hot glycol return header will operate at 100-110C. The plant design currently...

Hi, Andrew The maximum process side temperature I have is 140C, in one exchanger in the plant. All others are 130C or less. Based on this, EG/DEG are candidates--please let me know if you disagree. I hadn't considered EG, but I will now--thanks. (I've heard in the past that EG's vapour...

Dear Yorkman, Propylene glycol doesn't quite have the thermal stability we need. While toxicity is important, the application is for the oil industry. Proper controls will be in place to minimize leaks and spills and for their mitigation if they occur. You're on TV? Cool. Thanks for the...

My past experience is with DEG/Water solutions for mild heating/cooling applications (40 deg C-150 deg C temperature range). However, many of my colleagues in my new place of work have experience only with TEG/Water solutions for these services. They say it's better because it's more stable at...

Hello, If ASME B31.3 applies to your jurisdition, this may be more appropriate for your device. It sounds to me more like a piping component than a vessel. If the individual components used are in compliance with B31.3, and they are assembled in compliance with B31.3, then you've got a pretty...

Thanks to both Montemayor and J. Alvarez. Input much appreciated, and will keep all points in mind as I move forward. Regards, R

The existing preheat train first heats the crude (enters at 80C or so) with a side draw (VGO at about 200C) from the asphalt column. Then the feed is further heated with the asphalt from the bottom of the asphalt stripper (300+C). The LMTD's in these exchangers are in the 70-80C range. The...

I have a project to increase the throughput in an asphalt plant. One of my ideas is to increase the temperature entering the first flash vessel in the unit, by making the feed/preheat train more efficient. There is no fired heater upstream of the first flash vessel and to keep op costs and cap...

This is info for Isofilm, regarding the PQ curve for the glycol pump. The tracing for the spill tray will be part of a larger heat tracing network in the plant. The pumps deadhead at 350 ft of TDH and pump from a suction tank kept at 11 psig. The operating point on the curve is at 1633 USGPM...

D'oh! Sounds like what's called a pump curve around here. Ok, I'm going to the site this coming week. Will get the PQ curve and report the pertinent details asap. Thanks, R

Thanks isofilm, I'll check into FOAMGLAS. Hadn't heard of it before. Sorry, what's a PQ curve? I'm not familiar with that term. I believe that the glycol supply temperature is 70C, but need to confirm this (it may be a bit hotter); the geographical location is northern Alberta. Regards...

I need to heat trace a spill collection device to prevent icing up in winter. The heat medium is glycol/water; I'll find out the flow rate and supply temperature next week. The tracing will likely be laid in 2" of light-weight concrete, with the spill tray (steel) laid on top of that. My hokey...

To wilg: You've given me a lot to think about. I even got out my old text book from school to look up drag coefficients as a result of seeing the Malewicki equation. Thanks! For now, I think I'll take a pass on the "coast" equation--it probably doesn't have a term for exerting the...

I have read everybody's answers with interest. wilg and MintJulep came the closest to answering the question I thought I had asked. Thanks, guys! To wilg, regarding the Altitude Prediction chart equation: This looks really good. Are the units SI, metric, or Imperial? I'm assuming V is...

This is not a work-related question (at least, I don't think it has any practical application, but I could be wrong!), but it's been bugging me for awhile. Figured HVAC folks would be best equipped to answer it. Have you ever noticed that, when you hit a balloon with your hand to try to pass...

Thanks, Brian You are right--20/20 hindsight. Every time I troubleshoot something and find the "answer", I'm happy for about 5 seconds. Then I start kicking myself because I didn't find it faster! But it's sure fun to work on these puzzles, and I never forget the lessons they teach...

I don't know how many people will read this, but the mystery is solved, and there are one or two lessons in it. When we take instrumentation and control courses in school or get sent on courses for work, the focus on pressure drops tends to be on the pressure drop through control valves. The...

TD2K: Thanks for the encouragement, and for the story. Work in real plants doesn't match the text books all the time, does it. That's when things get fun. The fact that there's a pile of money at stake either way (whether you're right or whether you're wrong) adds to the excitement. The...

Thanks to TD2K and mpoffe for the flushing ideas. I'm going to discuss them with the contract online cleaning guys, and with the site lab guy. I've rechecked my calculations. There is DEFINITELY a pressure drop problem in the system. So thanks everybody for your input; I'll have that much...