air compressors for pumps, etc

[mendodistilling]

What do you use and why? how about used? any issues I should consider? I'm looking to use these pumps in at least 2 places routinely at the same time so i'm considering putting 1'' pipe all around the distillery, which is quite large. how about benefits of vertical or horizontal tanks? if im a pumpin fool and it runs pretty constant would there be any duty cycle ratings I'd need? i'm about gts now. figured id stop in here and see what you guys thought. got a new carlsen pump and i think im more happy about how nice it rolls and moves around on the cart than the pumps potential. i cant wait to add little hooks and things on it.

[bluestar]

Be very careful to calculate the load you will apply. If you are using the compressed air for pumps, know that the ratings on smaller compressors are for intermittent usage, and therefore you can't run those pumps continuously at full load. If you are going to use them for mixers, know that mixers with larger torque require A LOT of volume, continuously, and you will need a very large compressor with a large ballast to provide that. Don't forget your oil and water collection and filter in line. Having as large a pipe as possible provides additional ballast for the system, and reduces pressure drop effects when trying to run two things at once. Which is another sizing issue.

Finally, don't bother with a used one, unless you ASSUME you might have to replace the tank and/or compressor and/or motor and/or pulley. All of these parts wear. Even the ballast tank, because it can rust from the inside from moisture. Make sure you have an industrial quality unit.

[nick jones]

Air is a convienient power source, but electric is cheaper. Imagine if someone were to ask a similar question about electricity:

What kind of electricity is best? How much? AC or DC? How many volts? Single phase or three phase?

The answer depends entirely on the application, of course.

Sometimes a large air compressor (perhaps with 1" mains as you say) is appropriate, and sometimes you're better off with multiple smaller compressors at the point of use.

Without any more info on your intended use(s), its hard to give a recommendation. But if you're going to go with only one unit, and there is any chance that the air could ever touch your product, I'd go with an oil free compressor and either route the air through stainless or PEX. This would require oiling stations at the point of use for most air tools, pneumatic valves, etc, but better to add the oil than try to get rid of it IMHO.

Nick

[mendodistilling]

i meant brand wise, i'm looking at industrial rotary screw compressors, ive narrowed it down to a few brands and was looking for input from that perspectice. i'm hyper aware my 6hp will not run things. i have the minimal intelligence to do the math on useage to figure out how to size pipe, account for line friction, etc. i just wondered, from experience, which brands are industrial approved and which are import tin piles of garbage, which ones have lasted the test of time. the rusted tank is a good suggestion on used equipment, i have been told that not draining thetank after each use will leave residual water in the tank that will rust it out. ive got 480v 3 phase so thats what i'll be using. its interesting no one lines their tanks since this is an issue or purges them somehow. youd think theyd put a water catch low in the tank or something, like a plane does in their tanks.

thanks for your input on the line driers, thats great advice.

to nick, the electric is cheaper but air diaphram pumps are far gentler, more universal, work in high temps, have edpm ethanol tolderant parts, they will work recirculating hot acidic stillage backwards through my pot still, handle mixing boiling water, mixing semi viscous materials like corn mash, works with the brewery, works pumping grape must, pump overs, anything... so electric is inferior and its insurance rated near distilation operations like bottling, still mash charge, etc. so yes, its cheaper to go electric, but not much and with limitations that are far higher in the big picture.

[nick jones]

i just wondered, from experience, which brands are industrial approved and which are import tin piles of garbage,

I've got no direct experience with rotary screw, but they've gotten so much smaller and less expensive over the years that, like you, I think that I'd tend to lean in that direction if I were going to buy new.

I can say from experience, though, that I've seen used oilless Ingersol Rand piston compressors that look like they were dredged up from the bottom of a lake run for years under severe, almost abusive conditions. I've been thoroughly impressed by them and I wouldn't hesitate to buy a used one if the price was right.

It sounds like if one of the diaphrams in your pump were to rupture, you'd be exposing your product to your compressed air. That alone is a good enough reason to go oil-free if you ask me.

I've seen people deal with the issue of water in their tanks by hooking up a small solenoid valve on a timer to the drain port and blasting any water out of the bottom of the reservoir every few hours.

Mcmaster Carr has a good example of the sort of ancillary equipment that you'll aso want to he installing here.

Nick

[Denver Distiller]

Ditto on the Mcmaster carr diagram, and on the quality of Ingersol Rand. If you're running a pump with air, you can blow through gaskets and seals in no time if you're running without an air cooler.... especially in the summer, and especially if that pump is in continuous operation. You want cool, dry air.

[mendodistilling]

thanks, ill look into the diagram, I'm definitely seeing a reason for the air cooler, I've see air temps get pretty high just using air tools around the shop. the options for the two brands I was looking at were between ingersol rand and kaeser. Kaeser has an SF branch too, so that seems appealing since they are semi close.

Has anyone blown out the gaskets in their pumps? how many years of service do you get?

[nick jones]

I saw a pump rupture teflon diaphragms in a matter of months under moderate use. Don't remember the brand, but the whole thing was plastic... 3/4" inlets and outlets.

EPDM seems to me to be a superior material to teflon for a diaphragm, so I'd guess that your EPDM diaphragm will last longer, but it will rupture at some point or another, I'd wager. And as Denver says, the diaphragm is only one many possible seals that could have its life reduced by poor quality compressed air, so better to invest up-front in a well designed system than have to retrofit later after multiple equipment failures and repairs.

There are companies that specialize in the design and installation of compressed air systems, even sanitary ones, but I'm a DIY guy to a fault myself, so I understand the desire to do things oneself. Remember that, as Norgren says, "The amount of water vapor that can exist in any given volume of compressed air is directly proportional to the air temperature and inversely proportional to the pressure." So if you install an air cooler, you'll be lowering the dew point and therefore creating liquid water, which you will need to remove from the system. The whole thing really does get a little complex, especially if you're using one air compressor for multiple purposes. The way that I look at it, a company that will not only sell you a compressor, but also install the entire compressed air system and guarantee that it will work with your specific equipment for your specific needs could very well be worth the price tag, especially if you've got bigger things to be worrying about.

Nick

[Rickdiculous]

In my other life I teach glassblowing at a community college. We just installed an Atlas Copco http://www.atlascopco.com It has a max pressure of 185 psi, and we run a working line pressure of 120psi. It is regulated down in the various studios it is used in. With this one compressor we run, two sandblasters, 4 simple airlines, and four quick connect air tool lines. This baby runs constant pressure with almost everything running at once. I have never had all of them going at the same time, but I have no doubt it will run it. That said, it is an expensive unit. Ingersoll Rand makes a lot of traditional ballast air compressors which can be used to run pumps for a fraction 1/5 of the cost. Go big with one of them unless your operation is running multiple pumps all the time. I was just at Spring 44 Distilling for a Gin class at the ADI conference and they ran their agitator and pumps with one of those which I can't believe was any bigger than a 5hp. The 10 HP will only cost you $2600 where the rotary screw will be much higher.

Rick

[MG Thermal Consulting]

I do know that Champion (Quincy, IL) air compressor makes oil-less compressors, small ones 1/2 to 5 HP, used a lot with medical facilites.

They are recip type and can be duplexed up and such.

I believed they are owned by Quincy now, but have their own site with a list of distributors and service centers.

Mike