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can anyone recommend a way to dry out a compressor tank real well?? and also does anyone know of a good aftermarket intake filter system???thanksStangnetShop Full Of Stuff. Joey
Reply:1, Drain tank.2, close drain3, connect vacuum pump to tank4, pump down tank & hold under vacuum for 24 hours.Appreciation Gains You Recognition-
Reply:ughh, the one thing i don't have is a vacuum pump.....StangnetShop Full Of Stuff. Joey
Reply:common practice for clearing A/C system. Vac are available from rental or surplus.
Reply:Basic physics, any liquid boils off to vapor at a lower temperature under vacuum.Water will boil at around 70* around 28" of vacuum.I think you need to be more descriptive of your water problem.  Are you operating in an extreme humidity environment?Eliminating water before the air is compressed is almost impossible, but eliminating water from compressed air between the compressor and the tank is a walk in the park, with a water seperator.Appreciation Gains You Recognition-
Reply:Also, the water separator Franz mentions will work better if it is located some distance from your compressor tank.  Since hot air holds more moisture, you want to cool it as much as possible before it hits the separator.  I've even seen folks coil air hose between the tank and separator in a bucket of cold or ice water.  It works!  Copper line would be even better for heat transfer.If you have access to a second  compressor, Horrible Freight  sells a $10 air vacuum pump that would work very well to vacuum your tank.  On a tight A/C system, it'll pull -29.9" Hg in less than a minute.  I'd pump for at least 20-30 minutes.  I've had one of these pumps for years.  No moving parts, venturi action.  I used it a couple of months ago to evacuate the R-134A system when replacing a leaking condenser on my 97 Dakota.ONE DAY IN 1750, BERNOULLI WATCHED A TWIG  ACCELERATE  AT THE NARROW PART OF A SMALL STREAM - AND HE SAID TO HIMSELF, "SON-OF-A B!  CARBURETORS WILL WORK!"
Reply:If your looking for an intake system, to your compressor head, use oil filter automotive type or automotive type air filters with housing.  Seen it done many times and works well.  You could pipe the inlet portion outside of the shop, if the shop is dusty etc.To dry out an compressor tank, I am assuming that you have water in the bottom of it, what about air brake alcohol, the stuff they use for heavy truck.  Drain the tank as much as you can then work in the alcohol.a simple water separator as Fransz suggests should be on every air compressor, I used to use the sharp system, seemed to work well.  In our shop we use a complicated air dryer setup with two screw compressors, big dollars, around 60 thou, never a hint of moisture in three years.  Better quality filters that have the beads work well too, used to use this type on the paint booths years ago, as painting requires absolute dry air.There's a method to the madness, disregard the method and the madness begins!!
Reply:OP we gotta argue!I want compressed air as hot as possible at the seperator inlet, so I can chill it as fast and as much as possible in the seperator, and let the water fall out of the compressed air stream.Maximum temperature change causes maximum water fallout.I'm thinking Viperman's question should be how do I keep the water out of my compressor receiver?Appreciation Gains You Recognition-
Reply:Franz, think about it this way - with a longer run to the separator, the air progressively cools down in the line (the line should ideally gradually slope down with no low spots to trap water).  As the air cools, its relative humidity increases towards 100%, making it easier to precipitate out the water.  The ideal system would run the air through a chilled line into a refrigerated heat exchanger/separator unit.  I've heard that a couple of high quality auto paint shops here in humid Memphis actually do that.  You want to do all the cooling you can ahead of the separator, and chill the separator too, if you can.  If you chill after the separator and there's any significant moisture left, it'll be fisheye and blister city in your paint job.The type separator used makes a difference too.  They're sure not all equal.  I prefer the  centrifugal type with coalescer socks.  It spins the saturated air and slings the droplets to the outside of the chamber as the air passes through.
Reply:OP, I am tellin you, and I build the damn things, you want to drop temperature in a vertical stack seperator as fast as you can to condense water in the seperator.Forget all that guitar string Memphis crap the salesmen are pushing, and make one up for yourself out of 3 feet of 2" pipe.The plans are over onthe DARK Side, I posted them.I can take more water out of a cubic foot of compressed air with 3 feet of 2" pipe than any damn commercial seperator made. The only thing that competes with it is a refridgerated drier I have from IR.Just cooling the air won't drop the water out, you have to provide a cool condensing surface.  The 10hp IR I have in one shop with the factory aftercooler definitely puts colder air into the receiver, but it doesn't drop the water like a stack does.Appreciation Gains You Recognition-
Reply:Heres a picture of Franz's separator. It's made out of 2 " COPPER. David Attached ImagesDavid
Reply:i think i'll build a franz model separator, i wanted to get a paint sprayer and want the air to be dry as possible..thanks!!!StangnetShop Full Of Stuff. Joey
Reply:You guys just need to get your air from down here.  Thursday, you would only have had to worry about how to get the dirt out of it.Several hours of wind at 40 - 50 mph average speed with gusts to 67, last I heard. It was creating negative pressure in the little cheap new houses on the outskirts of town, making the windows on the downwind side howl like wolves.  All viperman would have had to do was set his tank outside for an hour or so with the line opened up to evacuate the water, assuming he could still find it afterwards, of course.  Might need to chain it down.I doubt that many of the paint shops were worrying about moisture at the time;  not much painting going on.
Reply:David;that's a good looking setup. I like the drops comming off of the top of the pipe. What are the two units down stream from the regulator?
Reply:Echo,Nice looking unit. Do you now have the coiled copper hooked up to anything or is acting more like a finned radiator? Attachment method?Allen
Reply:Franz said to run water thru the 1/4" tubing to cool the air. Also the thing isn't piped to "da Franz's specs" its supposed to go between the compressor and the tank. But the Quincy was new and I didn't feel like taking it apart yet so I put it after. So far it works as Franz advertised. All the joints between the separator and the reducing valve are silver soldered. After that they are just regular plumbing solder. This was a little hard to solder because inside that middle T is a 3/4" elbow turned down. I had to solder the el on inside the 2" T and then solder the pipe to the T and then the other 2" pipes going up and down. After that it was easy.  Jim the two units are a coalescor and a dessicant drier. I think Franz recommends a refridgerated dryer but I didn't have a $1000 for that. At the end of that line there is another air line connection and a dirt leg with a ball valve then it runs across the ceiling to some other stuff. The air is real dry and the plasma cutter works alot better  with this deal.David
Reply:echo, you might can make a scratch built refridgerated drier from this>> http://www.surpluscenter.com/item.as...tname=electricStangnetShop Full Of Stuff. Joey
Reply:Viperman, that unit would probably provide sufficient refridgeration for somebody in your humidity zone to run a chiller jacket on the seperator column.The drawback would be the shipping would probably kill you, and by the time United Parcel Smashers got it to you the unit would be scrap.The JetSpray beverage dispensers also work well as a chilled water unit, as do wall mounted drinking fountains.Just be sure the unit is kept in an upright orientation, or compressor oil will migrate to the evaporator, and the compressor will self destruct.Appreciation Gains You Recognition-
Reply:We have one of those $1000 refiridgerated driers. it doesn't work worth a damn. We ended up buying 40 water seperators and putting the right next to the hose drops.   Seperator-nipple-quick connect         thats how we ended up doing it.
Reply:i got a small inline filter that has removed a bit of the water, then i filled the tank and blew out the hoses twice and got out what was in the hoses. now i just need to setup an intake filter and make one of franz's separaters for mounting in the shop.StangnetShop Full Of Stuff. Joey
Reply:Viperman, deconfugle me, what do you hope to remove with the intake filter, other than dust?Jimmyed, where are you located and what type of refridgerated drier are you using?  Something is radicly wrong if a refredgerated drier isn't pulling water out of the air.Appreciation Gains You Recognition-
Reply:Franz, I'm really intriqued by your design, I was thinking something along those lines a while ago, but my brain did not get as far as that.I have some questions:We are running 2 10 HP Quincy Compressors with 120 gallon tanks.  All tied into 1 inch copper running throughout the barn.  Their's an auto drain tied into the tanks, drains every 2 hours or so.I would rather run the condensing stack past the 2 compressors, as I do not wish to get into re-pluming the compressors to the tank.How well would this contraption work if made out of 4 inch pipe or something like that?  I saw on your other threads that 2 inch is optimal, just wondering though.  It would be much easier to build 1 instead of 3 or so.We are running air gates off of these compressors, and wrecks havock at certain times of the year with the moisture in the lines.  I do not know CFM usage specs, but it does kick the compressor on quite regularly at 125 psi, and the second one comes on every once in a while when the tank pressure drops to below 100 psi.Thanks!
Reply:Bolt, to get optimal air/water seperation, the seperator must be located where it can effect optimal temperature change.  Since compressed air is hottest when it leaves the compressor, running to a seperator then, allows you to cool the air most.Seperators will work on air after it leaves the receiver, but the efficiency of the units is considerably lower than on a seperator between the compressor and receiver.I just installed an IR 10hp unit that employs a large air to air heat exchanger (similar to a car radiator) that drops around 40 degrees from the air stream, and theoreticly dumps the retained moisture the cooled air can't carry into the receiver.  Frankly, I have little confidence this system works.The "Franzinator" column does a couple things to the air stream, first, turning the hot air down, so it has to make a 180 degree turn to reach the outlet to the receiver.  Second, the air expands, and looses some temperature due to the expansion.  Third, the compressed air stream has to contact the cold surface on the inside of the column.  Over the 20+ years I've built these, a few engineers have shared their thoughts with me, and the consensus of opinions is that all 3 changes in the air stream cause the compressed air to drop moisture.When you pull apart one of the DeVilbiss seperators, the design is very similar, although they employ some additional baffels to slow the air stream, and cause it to drop water.Over time, I've tried "improving" on the design, and have found very little improvement available.  The only improvement I found that is truly productive is cooling the column itself by use of a liquid on the outside to actually chill the column, and therefore cause it to condense more water from the air stream.Chilling can be accomplished either by winding a water coil around the column, and soldering it to the column for thermal conductivity, or encasing the column in a water jacket.  Adding air fins to the outside of the column didn't appear to add to the cooling enough to matter.As far as pipe size is concerned, STAY with 2" pipe and a 1/2" inlet and outlet.  The guy who originally turned me on to this idea said the porportionality of those sizes was important, and my experiments have proven him right.  If you need more thruput of air than this sizing will provide, use multiple columns.Also, when installing multiple columns, do NOT manifold the moisture drain ahead of the drain solonoid,  this becomes counter productive to effective draining.  A timer that opens the drain solonoid for a few seconds at each compressor startup both drains the column and provides for a softer compressor start and lower electric demand.By air gates, are you talking about cylinder operated gate valves on hoppers?Also, are your machines alternating start, or does one machine bear the brunt of the work?Appreciation Gains You Recognition-
Reply:franz, i wanted an intake filter to control dust from getting inside the pump, i wanted moisture filter to keep water out of the lines.hope that clarified someStangnetShop Full Of Stuff. Joey
Reply:Our machines are set up that one is the primary, the other the secondary.  Once a month the switch is flipped to make the other carry the main load.The reason I want to put the dryer past the compressors is to make a few less of them, as it would take 4 of them to make a 1 inch pipe, but I don't know how much of that 1 inch capacity is needed.I have the ability to run a good flow of water through a coil or jacket around it, as there is a heat exchanger setup for milk quite similarly, just tap off that water supply.  In the future, this will be converted to a glycol mixture, so if I ran this through the air dryer too, I would have alot of temperature differential.The air gates are indexing and release gates in a dairy barn, and one 35 foot wide crowd gate running on a track, with an air orbit motor.  Also, two 12 inch pop up flush valves are held shut with this air pressure.Originally posted by vipermanz franz, i wanted an intake filter to control dust from getting inside the pump, i wanted moisture filter to keep water out of the lines.hope that clarified some
Reply:OK Belt, now I'm beginning to understand.Then again, I'm the guy who dragged home a 300 gal milk tank with the thought of making it into a hottub.Question #1, where are you sucking your intake air from?  Milking parlors are hi humidity and corrosive atmousphere.How many cows you running thru there?Have you looked at manure digesting for methane production?Appreciation Gains You Recognition-
Reply:Franz, I will attach some pics to get a better idea of the setup.  The compressors sit in the equipment room, warm and a little moist, but nothing real extreme, allthough I will grant every little bit helps.  They each have a 1 1/4 pipe coming out with a filter on em, right off the compressor.  Would it be acceptable to tie these together and run a 2 inch input line to the great outdoors?We are running abouts 1100 cows through the barn, 3x a day.  So we are milking about 21 to 22 hours a day right now.We don't currently see a need to digest our manure, we currently seperate the solids out of it and use that to spread on fields.  The water is stored in a 16 million gallon pond that catches all that water, wash water, rain water, runnoff, and the like.  This is run through a center pivot and used to irrigate a crop as well. Attached Images
Reply:This is the crowd gate, 35 feet wide, runs on a set of tracks to bring the cows up to the parlor, reducing the holding pen size, enabling faster loading times. Attached Images
Reply:And this is the parlor, as viewed from the back, where the cows enter.  All the gates run on air, they are currenly in as far as they go, and rise up to release the cows.  They are able to move forward a few inches to accomidate bigger cows.  The gate at the entrance slides shut.  Beside these (right off the picture) are the flush valves, they pop out of the concrete and flush it down, greatly cutting down on cleanup time. Attached Images
Reply:Bolt, you are definitely running a sufficient number of cows thru to make some extra money generating electricity.  Penn Power is a partner in a couple plants in Minnesota, and 1000 cows a day is the cost/effective point from what I've read.Surplus heat from power generation is used to heat the lagoon and speed up digestion.  There's probably enough surplus heat to heat wash water especially if combined with recovered heat from primary milk cooling.  Oddly, 20 years ago when we tried convincing cow farmers they could save money by preheating wash water and cooling milk they were sure we were trying to rip them off.The manure/electricity business will probably be seeing some big changes if they are able to drive Capstone Turbine units with manure methane.There are some studys being run now to determine if the manure that has been digested looses any nutrient value when applied to fields.  The study is relatively new, so the main result has been that digested manure smells a lot less than raw manure.As far as combining the input stacks and drawing outside air, go for it.  2" would be sufficient, but 3" would be better.  Based on what the SCUBA guys tell me, you'll also be a lot better off if you have the input 12 feet above ground.  A diesel truck air cleaner works very well on the compressor intake.Any water you don't have to take out of compressed air is a hell of a lot better than the best water seperator.Do you have accumulator tanks along the iar line, or are you totally dependant on line volume and receiver capacity?Appreciation Gains You Recognition-
Reply:Franz, I do agree with the facts surrounding methane digestion, I just think it is tough to make it work as effective as you'd like.  First of all, power here doesn't cost as much as it does up there, we are only paying 3 to 4 cents per kW at the top end of our grid, which is where the power would come off of the bill.  Second of all, the distance to the barn and pond is quite far to be running heating lines, power lines, over 1700 feet to the pond.We didn't even bother to get a heat exchanger setup off of cooled milk, it just isn't worth it with the water temps we have down here.All this would easy change if the gas prices go up alot more again.Would one of these filters be sufficient, we run a bunch of these on other air lines, is a fairly cheap priced filter, I find the ones on the compressor to be quite pricey.Thats a 4 inch schedule 40 PVC that filter is on, for refference. Attached Images
Reply:Bolt that filter in the pic looks about the size normally used on a 5hp compressor.  If I recall, you're runnin a pair of 10 hp machines, and if you use an undersized filter you are wasting energy.  You gotta bear in mind that filters get plugged up fairly quick, so it's a good idea to size the filter to the machine figuring the filter is 50% plugged.Damn 4 cents a KWH would be paradise here.Manure to energy is a BIG coming attraction, and you'll be seeing it sooner than you think.  Penn Power is a major investor in these systems, making electric from everything from cow to human, and moving across the country looking for manure.   While about every other utility in the country is getting rid of generation, Penn is buying generator plants.  They bought all of Montana Power's generation a few years back.If I was in your boots, I'd be doin a little preliminary lookin at what is available.  The articles I read say the power company pays for most of the plant, and partners with the manure producer.Appreciation Gains You Recognition-
Reply:Franz, that filter is about 2x the size of what is on each of the air compressors now.One of my main problems is where to mount the filter, is there a setup i can run that has the filter mounted inside the barn, and a inlet running to the outside?What about wind power, we sure got plenty of that stuff out here.  I know one guy that was buying a diesel generator to run his dairy off of, ended up getting a larger one, sells power back to the grid at peak times.  We only run a 230 kW generator for standby backup.  I think he probably uses 350 to 400, and has a 600 kW genset.  That setup in his particular application basicly paid for the thing soon enough.
Reply:Bolt, letme try explainin air intake filters this way, did you ever try drivin a pickup truck 20 miles with the choke on?  If a compressor has to suck air thru the filter it's spendin more money to make the same cubic foot of air at 90psi than it does with free intake.In your application I'd look around for an old B model Mack air filter that uses an oil bath element and put  that in theintake piping.Diesel cogen is very price sensitive to fuel costs.  Diesel may become cost effective in peak shaving and load shedding if your demand costs are high like mine, around 8 cents/kwh.  If you have a fluctuating load with peaks, Diesel may be cost effective.We did a lot of it here back in the mid 80s, and most of the plants got shut down when Diesel went above 87 cents a gallon.Another problem with cogen setups is in order to get tax incentives you have to recover more than 85% of the input BTU fuel value.  In your application, that might become effective by having an air compressor, or refridgeration compressor on the engine shaft, and using the waste heat from the machine for water heating.  CoGen is a very wacky business.If you want to investigate wind, I can provide you with a web site, but be sitting down and have an oxygen tank ready when you see the prices.Diesel sets are fairly cheap right now, CAT is stuck with a lot of inventory because they got cute back in the Califooey power shortage and only rented machines instead of selling them.  Most of the East Coast rental fleet has been shipped to Iraq, but there are at least 200 sets advertised in Rock & Dirt.  Since nothing is happening in the oil business down your way, that's another inventory looking for a home.Appreciation Gains You Recognition-
Reply:I understand the logic behind the air filter, I just didn't know how much it needs.  This the filter that came on the aircompressors straight from Quincyhttp://catalog.baldwinfilter.com/Par...tnumber=PA2038I don't see why they would put that small of one on there.Definately an over abundance of gensets for sale.  We purchased a Chevy 350 50 kW generator to run a pond pump, got it for 50-60% of what they were selling for a year ago, just because Atmos Energy over purchased a bunch.  Converted it to propane, run it for a couple hundred hours a year.  We don't run this much, so the relative innefficiency of it doesn't bother me too much, still costs a third of what a diesel would for that application.Last edited by Bolt; 02-25-2004 at 03:58 AM.
Reply:Who was the first person to look at a cow and say, "I think I'll squeeze these dangly things here, and drink whatever comes out?"
Reply:My great great great great grandfather.LOLI've wondered about that fact too, why cow's milk.  But hey, I aint complaining.  It's been my family's lifeline for generations now.
Reply:Bolt, there are a couple things I'll say about compressor manufacturers and the air cleaners they sell;  Manufacturers also sell repair parts, lots of repair parts, manufacturers also write detailed specifications relative to compressor location and intake air that nobody bothers to read till the warranty claim is rejected.I've seen many compressors chewed up by bad quality intake air, and a lot of compressors that went to the grave with the original air cleaner still in place.Compressors rarely get serviced, until they display a major problem.  Were I doing your system, I'd use a truck air cleaner such as this,http://cgi.ebay.com/ws/eBayISAPI.dll...category=56991Over a 10 year period you'd have lower power use, and less compressor ware.  Most compressor problems tend to be valve related, and that's generally caused by filthy intake air.  Corrosive intake air is also a major failure cause.As to the first guy who looked at a cow and decided to pull on one of the dangly things,  I wonder more who was the first callous handed guy to survive pulling on one of the dangley things.Then again, I was the 5 year old kid who caused major problems in my rural school district by suggesting milk might be cow pee.  The position and shape of the dispenser made that a logical thought in my mind back then.Appreciation Gains You Recognition-
Reply:Thank's for all the help Franz, I'll let you know how it ends out.  I still don't feel like drilling a 3 1/2" hole (another one) through the roof.So the condensor of yours will not work effectively in a 1 inch design?
Reply:I want to make one of these. At least a resemblance of it: what size is the copper tubing ? the big piece looks like it might be 2" or so and the smaller tubing 1" ... is there a draincock at the bottom of the long 2" piece that isn't shown in the picture ?
Reply:Jack, I know this thing is described to death someplace on here, but I don't remember where.2" copper tubing for the body, 2x2x3/4 T for the inlet, with an elbow on the inside to direct the air down.  Also a 3/4 x 1/2 reducing bushing to make installing the L easy.Solder the L into the T with silver or braze to prevent the L from falling off when the 2" is soldered.Top & bottom can be reducing couplings or caps.Petcock on the bottom for draining.Be aware copper is not as efficient as black iron unless water cooling of the 2" chamber is employed.  Copper does not RADIATE heat.Appreciation Gains You Recognition-
Reply:Jack when I made the Franz-a -nator, what I did was take a round file and cut the stop out of the 2" by 3/4" T , Then take a piece of 3/4" pipe(all stuff was sanded and very clean) and run it into the T and put on the el inside the T. I then silver soldered the pipe with the el to the 2" T and the el inside the 2" T. I was also ready to solder the the 2 pieces of 2" pipe to the T too. I was using Silfos 15 and flux made for that.Then I put the ends on and the cutoffs,etc. I tonly took one 2"x3/4" T, 2-2"x3/4" reducing coulpings,some 2" and 3/4" pipe,a 3/4" el,and 1 -3/4" ball valves. DavidDavid
Reply:Earlier discussions and Franz's personal diagram of his water separator are at the following: http://www.hobartwelders.com/mboard/...ssor+air+drierAl
Reply:what is the big black can?
Reply:Ryel if you are talking about the picture above the first black item is a air pressure reulator, the second is a coalescor filter, and the third is a dessicant dryer(the long one) Jack the larger tubing is 2" the smaller tubing is 3/4" and there is a 3/4" ball valve at the bottom as a drain for the column. The thing gives real dry air for plasma and for a little Hvlp gun. DavidDavid
Reply:thanks for the info echo.the original Franz super-duper hi-res hand crafted CAD drawing:
Reply:Originally posted by Franz Be aware copper is not as efficient as black iron unless water cooling of the 2" chamber is employed.  Copper does not RADIATE heat.
Reply:Only way I can answer that is by saying I haven't had a rusty air situation in over 20 years of using these things.You'll get a lot more efficiency out of the iron unit than a copper housing, unless you have a conductive way to cool the copper housing.Appreciation Gains You Recognition-
Reply:I just thought it was easier to get a copper el into the 2" copper fitting,than it would be in black iron. I think alot of shops I have been in over the years,prefer black iron pipe for the air lines and I think thats the way its been for a long time. Probably the strongest and the best. I think galvanized might flake some, and thats why they use black iron pipe.  Maybe Franz has a easy way to get the street el inside the 2" iron T. Probably could weld it in, I didn't see if a el would slide in the 2" T and tread in fron the inside(I dont think it will,maybe a 1/2" el). DavidDavid