Using a hot water heater in your filtration process? Tell us about it.

[lancaster,pa]

Looking ahead to warmer weather and some changes in my filtration system. Noticed that a lot of you are using a hot water heater in your filtering process. A couple questions:

1. Gas or electric?
2. Material tank is constructed from?
3. Procedure for cleaning junk out of bottom of tank?
4. Specifics of how you are using the tank in the settling/filtration process.
5. Advice in choosing a tank?
6. What changes would you make in your present set-up?

Thanks. - Patrick

[Clay]

Looking ahead to warmer weather and some changes in my filtration system. Noticed that a lot of you are using a hot water heater in your filtering process. A couple questions:

1. Gas or electric?
2. Material tank is constructed from?
3. Procedure for cleaning junk out of bottom of tank?
4. Specifics of how you are using the tank in the settling/filtration process.
5. Advice in choosing a tank?
6. What changes would you make in your present set-up?

Thanks. - Patrick

1. Electric only, gas is far to hot and open flames make me nervous around any kind of fuel.
2.steel
3.what junk are you thinking of cleaning? If your talking baout draining the settled junk out, just open the drain at the bottom of the heater.
4.The tank is used to heat the oil, let it settle and cool, drain off a few gallons to remove the settled snot and then pump it through your filters
5. any electric tank will due...don't get one too small, i wouldn't go smaller than 50 gal.
6. none

[Marv]

1. Electric only, gas is far to hot and open flames make me nervous around any kind of fuel.
2.steel
3.what junk are you thinking of cleaning? If your talking baout draining the settled junk out, just open the drain at the bottom of the heater.
4.The tank is used to heat the oil, let it settle and cool, drain off a few gallons to remove the settled snot and then pump it through your filters
5. any electric tank will due...don't get one too small, i wouldn't go smaller than 50 gal.
6. none

I'll quote Clay on this one since I have the same setup he has. I actually built mine off of some plans he sent me - which I think were based off the Frybrid plans.

So far it's worked great. It's probably the easiest way to filter this oil - at least from a time and effort investment.

Patrick, seems like I posted up my plans somewhere on here...you could probably find them with a quick search.

[skyskijason]

Electric water heater (previously discarded = FREE). Only using bottom element & t-stat and wired to 110v.

So far, all steel tanks - many 'newer' tanks have fiberglass lining inside, but none I've gotten that I know of.

I filter w/something like 5 gal bucket paint strainers (get'em at Sherwin Williams) before putting in WH. I figure eventually it'll have to be cleaned by removing bottom valve and rinsing w/diesel or bio-d. The idea is to keep chunks that'll interfere w/valves out.

I was happiest using vacuum pump to fill WH and regulated compressed air to empty and push thru filters. I set t-stat at 110-120* and set timer for 3-5hrs depending on how cold it is. Let 'settle' for at least 12hrs, longer if its still wet. I drain bottom until color changes, then hot pan test a sample. If its dry, everything above it is OK. I like to plumb WH so I draw 'good' oil from a few inches above bottom. The cone-up bottom makes getting that last little stream of 'nasty' hard to get out. Also, the 'bottom' stuff just gets added to next batch. I decided the oil below the heating element does not get heated and ends up looking like its much worse than it is...

I would look for an 80gal tank. Ya don't have to do that much at a time, but the procedure is the same for 30gals or 80gals. I also strongly recommend a site glass of sorts to monitor oil level in tank. I used 1/2" PEX and could still see level after 2 yrs. It's also rated for the temps and pressure. Avoid galvanized steel, and PVC use black iron fittings.

I'm rebuilding now, so changes... I originally used 30 mic water filter before still, even at $2ea - they are not very economical if the oil is actually dirty. I will use a 'strainer basket' w/1" fittings and a clear bowl before still in this version. Something easy to clean and re-use. Goldenrod makes SS strainer 'elements' and several choices available at Grainger. After still, I'll use a 30mic, then 10mic and finally 2mic spin-on filters and store clean oil in a 275gal tote.

I keep threatening to add blue jean leg 'filters' before the real filters. I did this for first year and almost never changed the real filters. The key is oil must be warm to flow thru them. I even clamped jean leg (sewed shut on one end) over a pipe and 'pushed' the oil thru at 5-10psi. This time, seriously considering sewing a 55gal drum size 'blue jean filter' and placing a drain in bottom of drum - allowing gravity/hands-off filtering. (or just cut bottom off closed-top drum and use bung holes for drains) I have access to a canvas shop (big a$$ sewing machines) - and may just buy new material to build the filter(s).

[lancaster,pa]

Thanks Clay. Is it correct that your tank is not galvanized. Think I remember seeing something about steel tanks with a fiberglass lining. Know anything about that? - Patrick

Thanks Marv. I'll take a look for your plans (kinda remember seeing them now that you mention it). - Patrick

[Marv]

Thanks Clay. Is it correct that your tank is not galvanized. Think I remember seeing something about steel tanks with a fiberglass lining. Know anything about that? - Patrick

Thanks Marv. I'll take a look for your plans (kinda remember seeing them now that you mention it). - Patrick

No problem man, you're welcome. I'm pretty sure they are on here, but if you can't find them, let me know and I'll email them to you.

Thanks!

[Clay]

Thanks Clay. Is it correct that your tank is not galvanized. Think I remember seeing something about steel tanks with a fiberglass lining. Know anything about that? - Patrick

No problem.
My tank is not galvanized as far as i know...some tanks are lined but mine is not to my knowledge.

[lancaster,pa]

Electric water heater (previously discarded = FREE). Only using bottom element & t-stat and wired to 110v.

So far, all steel tanks - many 'newer' tanks have fiberglass lining inside, but none I've gotten that I know of.

I filter w/something like 5 gal bucket paint strainers (get'em at Sherwin Williams) before putting in WH. I figure eventually it'll have to be cleaned by removing bottom valve and rinsing w/diesel or bio-d. The idea is to keep chunks that'll interfere w/valves out.

I was happiest using vacuum pump to fill WH and regulated compressed air to empty and push thru filters. I set t-stat at 110-120* and set timer for 3-5hrs depending on how cold it is. Let 'settle' for at least 12hrs, longer if its still wet. I drain bottom until color changes, then hot pan test a sample. If its dry, everything above it is OK. I like to plumb WH so I draw 'good' oil from a few inches above bottom. The cone-up bottom makes getting that last little stream of 'nasty' hard to get out. Also, the 'bottom' stuff just gets added to next batch. I decided the oil below the heating element does not get heated and ends up looking like its much worse than it is...

I would look for an 80gal tank. Ya don't have to do that much at a time, but the procedure is the same for 30gals or 80gals. I also strongly recommend a site glass of sorts to monitor oil level in tank. I used 1/2" PEX and could still see level after 2 yrs. It's also rated for the temps and pressure. Avoid galvanized steel, and PVC use black iron fittings.

I'm rebuilding now, so changes... I originally used 30 mic water filter before still, even at $2ea - they are not very economical if the oil is actually dirty. I will use a 'strainer basket' w/1" fittings and a clear bowl before still in this version. Something easy to clean and re-use. Goldenrod makes SS strainer 'elements' and several choices available at Grainger. After still, I'll use a 30mic, then 10mic and finally 2mic spin-on filters and store clean oil in a 275gal tote.

I keep threatening to add blue jean leg 'filters' before the real filters. I did this for first year and almost never changed the real filters. The key is oil must be warm to flow thru them. I even clamped jean leg (sewed shut on one end) over a pipe and 'pushed' the oil thru at 5-10psi. This time, seriously considering sewing a 55gal drum size 'blue jean filter' and placing a drain in bottom of drum - allowing gravity/hands-off filtering. (or just cut bottom off closed-top drum and use bung holes for drains) I have access to a canvas shop (big a$$ sewing machines) - and may just buy new material to build the filter(s).

Thanks Jason. Can you elaborate on how you did the site glass? Also, how do you plumb to draw oil from a few inches from the bottom? Aren't you limited to using the drain at the bottom of the WH? - Patrick

[skyskijason]

No problem Patrick, I put a tee on the bottom 'drain' and adapt to PEX above the tee then run PEX to top of WH - either using the 'hot' nozzle on top or looping back down to the where the top heating element (was). If you plan to 'suck' out of this bottom drain, the 'site glass' needs a valve so ya don't suck air thru it. The 'problem' I had using bottom drain was when I got to the 'good' oil - there was always still just a steak of milky stuff for a few gallons. Using a higher fitting, I can stop as soon as color changes from bottom. The bottom of these tanks is an inverted bowl, leaving a trough of sorts around perimeter. Any debris (rust, sediment, french fries) in the trough makes it hard for the heavier water to escape. If you use this fitting, it may help to tilt the tank slightly toward it??

The best still I've made was from an 80gal 'boiler'. It once had (9) 6000watt elements and ran on 3 phase/480v and had 1.25" inlet/outlets!!! So, I was able to use the lowest heating element hole for drawing good oil and just used the 2nd one up (maybe an inch higher) for the element. BTW, this thing was discarded behind grocery store (I just asked mgr if I could 'haul it off'!). Upon inspection, found it was leaking at a copper nipple fastened to the steel tank and connecting it to a SS union! Can you say galvanic corrosion aka 'bi-metallic' corrosion? The copper had failed in the presence of the 2 harder/more noble metals!

This still had some internal corrosion where bottom met sides. I discovered this when I was banging the tank around removing scale, etc from inside. Before adding VO, I ground the area clean and added JB weld. 1.5 years and 1000's of gallons later, I forgot to turn the regulator down on the air while emptying tank and 60 psi made my patch leak. (fwiw, that was the LAST spill ever in my shop - that day I started building the 12x12 shed that now houses 'the grease'.) I'm thinking about cutting bottom off and using it upside down as a mist washing tank - since the top is domed and there is a fitting in center of dome. A 'free' conical bottom tank of sorts...

I have also used a tee in bottom element hole of normal WH and inserted the element thru the tee and draw 'good' oil from bottom/side of tee.

Some other stuff to know. The 'cold' or inlet fitting has a pipe that extends to the bottom of heater. Cool eh? EXCEPT that it has a 'anti-siphon' HOLE near the top of pipe. You can still use it as a fill port - but not outlet. Some remove the anodes and press. relief valves. I haven't removed them (couldn't), but suspect they got a film of poly on them right away and likely stopped 'reacting' with the VO! (hopefully? ) Now I have an adjustable relief valve to use (make sure you plumb it into a bucket or drum!!) Never FILL the heater to the top. IIRC, VO expands about 5% w/a 100* rise, don't quote me though! For this reason, its prolly a good idea to route a vent line to a bucket/drum as well. I had a 'safe fill' mark on my site glass.

Another advantage is using vacuum to dewater in the still. This is generally not considered to be a good idea, as it leaves stuff in the oil that settling gets rid of. I used vacuum several times when I was in a hurry and still had a few bubbles in HPT after heat/settle/drain. 30 mins at 25hg and NO BUBBLES... I promise there is no faster way to move 80 gals than vacuum. I generally charge tank to 25-28hg, then suck oil in. Even oil that looks solid enough to stand on!!! And of course not too many pumps will push at 75psi (max rating on most WH) thru as many filters as you want.:chuckles:

Keep us posted!

Wow, this is like $0.10 worth! Sorry for such a loooong reply.

[lancaster,pa]

Jason,
The long reply is appreciated. Answered my questions plus lots of additional info. Thanks. - Patrick

[biostroker]

Why shouldn't galvanized steel be used? I used galvanized steel for most of the fittings on my set-up (pump fittings, filter inlets/outlets, etc.) Should I change them all to black pipe?

[Marv]

Bio, in general, I believe steel period promotes polymerization. I do know steel tanks will lead to major, major problems over time. Galvanized on the other hand, I'm not so sure. I imagine over time you would see similar results.

About 98% of my fittings on my filtering setup are black pipe, however I do have one or two fittings I had to use galvanized one since they didn't offer it in black pipe.

Thanks!

[biostroker]

Bio, in general, I believe steel period promotes polymerization. I do know steel tanks will lead to major, major problems over time. Galvanized on the other hand, I'm not so sure. I imagine over time you would see similar results.

About 98% of my fittings on my filtering setup are black pipe, however I do have one or two fittings I had to use galvanized one since they didn't offer it in black pipe.

Thanks!

Thanks Marv. I wasn't aware that steel promoted polymerization-when I was building my dewatering and filtering set up and I was at the hardware store I figured galvanized steel would be better to use than black pipe. Wrong assumption, apparently! Is there any way to test if I'm having a polymerization problem? I'm not even sure what the signs of it are. What's black pipe made out of?

[lancaster,pa]

Why shouldn't galvanized steel be used? I used galvanized steel for most of the fittings on my set-up (pump fittings, filter inlets/outlets, etc.) Should I change them all to black pipe?

bio,
I believe that the galvanized coating reacts with veg even more so than just steel. Always wondered what black pipe is made out of as well. - Patrick

[HORSEMOVER]

I used mostly galvanized when I built mine. I thought about switching them out but it is working fine so far. I figure sometime this summer I will tear apart some of it and check the inside of the pipe to see how bad it is.