Sizing an Air Compressor

[ntertell]

Hello, I'm having a tough time sizing an air compressor for my startup brewery. I've been getting different advice from a few different sales guys, and wanted to see if any of you have some advice.

Is anyone using a rotary screw compressor that takes oil, or are oil-less compressors the only way to go?

Other sales guys have told me that I'd be better off with a reciprocating piston compressor instead of a rotary screw compressor, and yet another guy said I'd be better off with an enclosed scroll system.

I'm also wondering if say a 15HP Ingersoll Rand 3-phase power 80 gallon tank rotary screw Total Air System (with dryers, separators, and filters) would be appropriate, or if I'd need additional air storage capacity.

I'll be using about 25 peak CFM in the brewhouse area (brewhouse valves and mash filter), and then 150 feet away in the packaging area i'll be using another 20 peak CFM on 5 machines, for an approximate 45 total peak CFM. I'm wondering if I put a compressor like the one mentioned above in the Packaging area, if that will be sufficient for everything, or if I should install a separate 80 gallon compressed air storage tank in the Brewhouse that I connect to the compressor in the Packaging area?

Please let me know what you guys think.

Cheers!
Nathan

[Starcat]

Setup

Nathan, if you are very close to your chosen compressor capacity with respect to usage, you will be better off with larger than 80 gal extra on your receiver. I'd suggest at least 275 gallon and your receiver needs to be close coupled right after your Drier. This is based on the air we use compared to you saying you need CFM in the 40 range. I would advise speaking with and Engineer so you are positive about size requirements for your load. The good dealers usually have this kind of expertise, such Ingersol Rand.
Your machine will be rated at MAX number of starts per hour which you don't want to exceed. A larger receiver system will widen the time between compressor cycles.

They are better of in a mechanical room on the perimeter if possible because they can be loud. You need service valves throughout the system so you can valve things off when you have to make repairs. 2 compressors are better than one for a production house. Every vessel including the drier are setup with automatic drain units. Its good practice to build a manifold at the drier so that you can take the drier and filter cans out for quick service. On reciprocating systems your pre filter will need very regular service.

[ntertell]

Thank you Starcat!

[TGTimm]

What Warren said--plus this: in addition to the maximum storage close-coupled to the compressors/driers, add some point-of-use storage tanks. Why? Most equipment uses short bursts of air at high volume and lower pressure. A "surge tank" at your point-of-use (bottlers, keg washer/filler, etc), fed with line pressure (usually 100-125 psi for safety and choice of plumbing), with a high-flow regulator to your equipment. This eliminates the need for over-sized lines for your 150' run and helps keep the compressors from short-cycling.

Basically, 30 gal of air at 100 psi = 100 gal at 30 psi. Be sure the surge tanks have drains, also, and consider micro-filters after the high-flow regulators.

I can't agree more with what Warren wrote regarding branch/zone valves--you can never have enough. Being able to service one piece of equipment or zone of the building while everything else is still running saves time and money. This goes for everything that has pipes or tubing in the brewery--water, steam, CO2, etc.