The Smallest Minority on earth is the individual. Those who deny individual rights cannot claim to be defenders of minorities. - Ayn Rand
Cool, I like big industrial machines and plants.
Me, too, Fabio.
So what does a slurry pump do (besides pump slurry)? And what is slurry? Sounds like one of those frozen soft drinks. (Try the new Carl's Jr. Slurry!)
Slurry is defined as solids suspended in a liquid. In this case it's crushed rock in water. You have to move that water pretty fast to keep the crushed rock suspended in it. The crushed rock varies in particle size from gravel to sand to talcum powder. These pumps move the slurry to cyclone separators where anything larger than very fine sand gets separated out and returned to the mill to be ground further, and the finer stuff moves on to the flotation cells where it is chemically treated to pull out the metal-bearing compounds, which float to the top of the cells in a foam and are scraped off.
Thanks! You explained that very well.
Recycle pumps for wet scrubber for coal power plant?
Nope. Discharge from two 18,000Hp ball mills. These feed cyclone separators that thicken up the slurry before being fed into the flotation cells for mineral separation.
Variable speed AC drives? Or are they DC? One of my previous rides, which used AC to DC, (via Motor-Generator sets),for the barge transporter drive system:
Maintaining these contraptions was a right royal PITA, I can tell you.
AC drives. You see very few large DC motors anymore. I can't tell you the last time I saw an MG set. Solid-state power electronic technology and microprocessors have gotten to be much, much better in the last twenty years or so. DC has become a very niche market.
Sub force still uses MGs; utterly filthy machines. Slowly making the transition to solid-state, thank goodness. (You need at least a basic DC setup when you're relying on a battery to save you in crisis.)
You can run an inverter off of batteries. That's what UPS units do.
That's basically what they're moving to, but we're only on the cutting edge of the 90's or so in the major system elements. It's nice for the boats that have solid-state converters, since it takes a load off the electricians who have cognizance of literally almost every bit of gear on board.
The carbon dust in those MGs is fierce. They clean them regularly and just looking at them when they're done is enough to make you want to shower.
Whoops, that was me. I should also add that we keep some ship-vital elements on the DC bus, mostly (as far as I can tell) to minimize the number of failure points between the reliable power supply and the gear.
Mooring/anchor winches for a ship, and some cranes.
My present ride is a 6,000 horsepower diesel electric, we step down and rectify from 6.6kv to 690 DC for the Z drives. Gotta love Siemens NXPlus switchgear!
My first electrician job was aboard the Cableship Long Lines for AT&T, (when it was still in the undersea cable business), and she was a turbo-electric. We like DC drives when precise speed control is an issue.
Built like a brick shit-house, too. Those old U-boat shipyard workers knew their stuff.
Sounds like an immense DC stepping motor.
No stepping on the Long Lines, just God's Own variable resistor bank for the shunt field,(for those of you non-dinosaur-qualified electros: increasing the resistance in the shunt means more current flowing through the armature via the commutator, the "filthy" part that Xenocles was talking about).
If stepping the shunt is your bag, then you're looking at mooring and crane winches, (for "let's take coffee", "very slow", and "just slow" speeds.
Trust me, anything you could do with a DC motor, you now CAN do with an AC motor. DC motors are becoming dinosaurs.
True dat, but the amount of cash invested in all that copper and skilled manpower to manufacture them keeps 'em around.
And since most of them WERE built like brick shithouses, they still do the job.
DC motors are becoming dinosaurs.
Perhaps. Perhaps they're just becoming a niche item. The reason I noted a similarity to DC stepping motors is because you'll still find them in scanners, faxes, printers and photocopiers today. I'm no electronics engineer, and haven't been a tech for years, but apparently nothing else can match them for starting at a very precise moment, stopping at a very precise moment, and proceeding at a very precise (and very precisely variable) pace. In other words, good electromechanical drivers for small robots doing precision jobs.
A draftsman making a copy only needs a few thousandths of an inch error to make his copy unusable. An attorney's situation can be nearly that bad, depending on what the copy is for.
As I've said, I won't claim to know the math, or be anywhere near the front of the technology curve. I just know where I've seen them (and still see them) used, and why the reasons I was given made sense to me.
True, but there's a world of difference between a brushless stepper motor and a shunt-wound, series-wound, or compound-wound industrial DC motor. For all intents and purposes, the physical difference between a DC stepper and an AC servo motor is minor. The difference between a DC propulsion motor and the motor in an ABB Azipod is significant.
My college roommate used to keep a slurry pumping text next to his bed to help with insomnia. He double majored in ChemE and Biochem, so he wasn't even from the "You want fries with that" crowd. He just found it... soothing.
Thanks, Kevin. That's the stuff we're into repairing and refurbishing at my place.Fun stuff...
My brother doesn't share pics of that plant when he comes back....if he takes any.
Laser Coat! Pew! Pew! Pew!
Awwwright! I was just up at one of my stations looking at my 8000-HP drive this afternoon. Natural gas is ever so much less of a problem to pump than slurry...
I can do better. The SAG mill at this facility is 22,000Hp!
That's a LOT of rock!
22,000! We're installing several of the 22,000 HP synchronous motors on a pipeline upgrade moving gas to Florida markets. I've been in on the project since early on. Stories will start when I get to the sites in late summer of this year...
as a millwright, i enjoy seeing and hearing about large industrial equipment. i helped install a large id/od fan at a small power plant near my home. the motor drew one megawatt from house power, and sucked all the exhaust out of the smoke stack, through a baghouse filter, and then blew it back out the stack. around 450,000 cubic feet per min. fan rotor on shaft weighed either 14k or 17k. 19 inch shaft at motor, 12 inch on other end. was kinda fun, for a couple of months.
"No, I'm not that fat..."
Funny how often I say that myself. A recent house-guest was commenting on some shooting trophies gathering dust in a corner. I had to admit that I hadn't been competing since my jacket shrank a couple of sizes. *DONT_KNOW*
I do not want to seem ignorant but what is the purpose of the larger sceme of things that this pump exists in. I.e., What the hell does the plant do?
This pump is located at a mine. It's in the sulfide ore cycle (as opposed to the oxide ore cycle). The ore is mined (chunks up to about 1.2 meters in size), crushed (1,000Hp crusher - chunks up to about 120mm in size), milled, (one 22,000Hp Semi-Autogenous Grinding [SAG] mill, two 18,000Hp ball mills - particles up to about 0.2mm in size) and then run through this pump. From here it goes through centrifugal cyclone separators where anything larger than 0.2mm is separated from the slurry stream and put back in the mills. Everything 0.2mm and smaller goes on to flotation cells where the material is agitated and chemicals are added to pull the metal compounds out of the rock. In this case, lead sulfide and zinc sulfide. Along with the lead are trace amounts of gold, silver, and copper. Different chemicals separate the lead from the zinc, so the first group of floatation cells separate out the lead/gold/silver/copper, then a second set of cells separate out the zinc. The metal-bearing components float to the surface in a foam, and the foam is scraped off the top of the flotation cells. This metal-rich slurry is then pumped to special filters where it is separated from the water carrying the solids, and the solids, now called "concentrates" are bagged for shipment to smelters for further processing.
We take our raping of Mother Gaia very seriously in the mining industry.
Thanks, I am glad you take it serious too many people just play at it :)
Camera's stink, film is bad, digital is as bad. The End.
Cool, and thanks for the tech story! My first thought (Before reading the comments) was "what the heck do you do with that much slurry, Spill Mountains?"