All,
There is a project at our site to inject sulfuric acid into one of our cooling towers to help descale or prevent scaling of our HX tubes. The cooling tower is a 3-cell design, with each cell's water level equalized. Circulation rate is about 20000 GPM total for the tower. Construction...
We are in the process of scoping for replacement of our underground firewater piping. It is currently an underground network of approximately 20,000 feet of a mix of mostly 6"-10" iron piping installed in the 1950's, and repeated leaks on the system are causing excessive maintenance spend for...
We have a boiler that has several tubes that have undergone overheating tube ruptures due to poor water treatment and subsequent tube blockages. We have fixed the feed water quality issue and have just completed an acid wash of the boiler to remove any blockages from the tubes, steam drum, mud...
What are the best practices for visually witnessing a boiler hydrostatic test? If the boiler hydrostatic test must be visually inspected from inside the firebox for tube leaks, the confined space entry is not technically zero energy. I could see a practice where the boiler is brought up to...
All,
Our plant (petrochemical processing) is going to begin adopting API 580 for Risk-Based inspections. Currently our program is time-based inspection intervals. Was looking for some industry guidance on % reduction for inspection costs by adopting RBI instead of time-based inspections, but...
Wanted to get anyone's thoughts and experiences on switching from steam turbine driven boiler draft fans to VFD driven fans. We are looking at significant capital spend rehabing our existing boiler draft fan steam turbines, which take steam off the desuperheaters of the boilers and let down...
Currently I am in the process of determining whether or not our current LEL detection system is necessary from a process safety and regulatory standpoint (located in US)
The way this system is set up is several vacuum distillation column vents, on the vapor outlets of the jet condensers, are...
I am trying to find guidance on roof access for above ground storage tanks. Some of our tanks have instrumentation/hatches that need to be accessed for routine inspections, and no platform/grating on the top of the tank roof that is supported externally. There is a safety concern around the...
I have a column overheads condenser, product on shell and cooling water on tubes, that began leaking a few weeks ago. The shell side pressure is near full vacuum and tube pressure around 50 psig. The leak appears to be real since we are showing water in the product, and the only source found...
Hi everyone
I have a question regarding hammering that occurs at low steam flow rates. So some background
There are 6 distillation column reboilers that run on 250# steam controlled with a steam control valve. The condensate outlet of each of these reboilers go to float traps on each...
I have a Goulds 1x2-10 1800 rpm 3 hp motor with a 9" impeller putting out 1200 GPH. It keeps tripping the overloads. The motor wasn't sized for curve runout, but still it pulls around 3.6 amps and overloads are 3.74. A small increase in flow trips it out.
So to live with it temporarily, I...
I have an orifice plate with a 0.9 beta ratio. I've never seen one so high and I don't even have flow coefficient data since crane 410 only goes up to 0.75. The problem with this meter is that it reads lower than the actual flow, by about 20% at Mac flow. I'm buying a new meter with a .7 beta...
I have a distillation column with 3 packed bed sections, no trays. I did some historical analysis on the column and noticed that as feed to the column goes up (range of 3500-8000 GPH), the top control temp (underneath the top bed of packing) also needed to be higher in order to keep the top...
I currently have a column that uses free 10# saturated steam injected in the column bottom as the boilup force. There are 22 trays in the bottom of the column, and two packed sections in the top. The column runs under vacuum at around 300 mmHg. Tray spacing is 12". Above tray 22 there is a...
I've always noticed that at the top of cooling water loops at a high point (80-100' above grade), a vacuum develops at the top when a high point bleed is opened. The downleg of the pipe goes back to the cooling tower 70' below. I've associated this with the freefall of liquid accelerating in...
I have a shell and tube exchanger with product on the tubes and 50# steam on the shell. For some reason, the outlet temp of the product side fell off in a matter of a few hours and the steam valve opened wide. The condensate out has a trap on it that is working properly.
I measured the skin...
I have a very low flow PD pump that puts an basic chemical into a product stream to raise pH. The flow of the chemical is typically 0.3 GPH and doesn't vary much. The PD pump flow is controlled by the stroke of the piston on a 1200 RPM motor. The flow is measured with a small coriolis meter...
I wanted to know if anyone has used Gore Style 800 Universal Pipe Gaskets. These gaskets seem almost too good to be true, especially since our maintenance staff has been reduced in the past few years and re-torquing gaskets has taken back seat to more pressing issues. Most of our processes are...
Looking for direction on a column we have been having problems with. Basically the overheads & bottoms product need to be a certain quality, but increasing reflux to get this quality will cause an undesirable light component to go out the bottom.
We have a set point bottom temperature that...
Wanted to test my theory with the engineers here. I have a distillation column with a thermosyphon reboiler at the bottom. We have 250# steam going through the tubes of the reboiler and product on the shell. Recently, we think we may have fouled the product side in a matter of hours. As soon...
