thread136-218042
I have done several pilot studies with VSEP filters on phosphoric acid. The goal wasn't increasing concentration, but that was a side effect. The removal of impurities causes an increase in strength of the filtrate.
There is also a commercial process using membranes to make...
One of my duties is running the QC laboratory, and I need some help on determining whether to throw away several thousand dollars of elemental standards due to the expiration date. I did a purge of our analytical standards in 2007, and was throwing away stuff from the 70's and 80's. Now most...
I am trying to improve the operation of an ammonia vaporizer in fertilizer production service. We switched ammonia providers last year, and am seeing a drop-off in vaporizer performance. The bottom of the bayonet-style vaporizer is full of water after a run, and there are significant rust...
We've got a centrifugal pump that transfers phosphoric acid from one vacuum evaporator to another. The suction line comes off the vapor body and drops about 50 ft to the pump inlet. The suction line has a U-shaped line above and below the liquid level, and a pipe comes off the mid-point of the...
Got a problem pump that is regularly breaking the seal faces. It's a vaneaxial pump used as a circulator on a vacuum evaporator in phosphoric acid service. 528 rpm, 27,000 gpm, 195F, 21 psi deltaP across the impeller. The current Flowserve seal gets broken about 5 times a year when the pump...
Looking for a production method of making ammonium fluoride from a starting material of fluorosilicic acid. Do I need to use ammonia or can I use ammonium hydroxide? I'm trying to avoid PSM materials if possible.
I have a problem pump that is a constant headache. It's an expeller-design centrifugal pump on the underflow from a phosphoric acid clarifier. The current pump seal will not survive in this service, mainly due to low flow and high inlet pressure:
1.5 sp. gr. phos acid
20 - 30% solids
52 feet...
I know about the depression of the melting point of a water/salt solution, but how does salt melt ice if they are both a solid. In other words, if I throw salt down on existing ice, there should be no reaction, eh?
Looking for some design programs for checking cooling tower design. Trying to spruce up a mechanical draft cross-flow tower that has seen better days, and I found a little MS-DOS program on ChEresources. Wondering if there is anything else out there?
I am interested in older mine and milling technology for gold mining in the American West, and I came across some displays of Wilfey tables in a miniature mill. I have found very little information on their actual design and operation - just enough to get me interested, actually. I would...
There was an exotic car made in the '70's that used a bare stainless steel as the body panels. It was called a Bricklin, and was only made for a few years. Does anyone know what type of stainless was used to skin it with?
I'm trying to figure out the minumum thickness of a 36" blind flange. I'm making a crud trap with some big HDPE pipe, and am going to use 2 blind flanges on the ends. I found a formula in Perry's:
t = d(3P/16S)^0.5
where d=inside diameter, P=internal pressure, S=allowable stress, and...
While trying to decide a suitable filler metal, I came across the following statement in a tech bulletin:
"Inconel 625 has columbium, which stabilizes the alloy against sensitization during welding."
What is weld sensitization?
By the way, I'm trying to choose between Inconel 625...
I'm trying to figure a way to clean heat exchanger tubes in a phosphoric acid evaporator. I've got calcium sulfate (gypsum) anhydrite deposits inside the tubes that defy attempts to chemical clean them away. I remember a way that we used to clean seawater evaporators in the Navy that was...
I'm trying to figure a way to clean heat exchanger tubes in a phosphoric acid evaporator. I've got calcium sulfate (gypsum) anhydrite deposits inside the tubes that defy attempts to chemical clean them away. I remember a way that we used to clean seawater evaporators in the Navy that was...
I'm looking for info on #2 fuel oil. We use it in floatation cells to beneficiate phosphate ore. I remember a old chemist who used to work in uranium solvent (SX) extraction telling me there were many "grades" of #2 fuel oil. He mentioned a brand or grade called 'napoleum' that he...
I'm looking for info on #2 fuel oil. We use it in floatation cells to beneficiate phosphate ore. I remember a old chemist who used to work in uranium solvent (SX) extraction telling me there were many "grades" of #2 fuel oil. He mentioned a brand or grade called 'napoleum' that he...
I'm looking for info on #2 fuel oil. We use it in floatation cells to beneficiate phosphate ore. I remember a old chemist who used to work in uranium solvent (SX) extraction telling me there were many "grades" of #2 fuel oil. He mentioned a brand or grade called 'napoleum' that he...
