Regenerating GFO

[barjam]

Unfortunately, I would agree except that if you throw a piece of MMLR in your tank you'll toast everything by a pH jump. That LR has sodium hxdroxide as the main component that drives up the pH and it takes months in the casting bin or in the soak tank to drop the pH. It's a little different since the NAOH in the rock is bound up internally, but still a concern for me.

Just my $0.02...

I'll try the tank water tonight though.

I regenerate in a BRS GFO reactor. Last time I regenerated I did 2 cups and ran roughly 5 gallons of RODI water through it and put it in the tank. I didn't notice any sort of PH issue on my 120 gallon tank. I tested PH maybe three hours after putting the GFO back online.

Let me know what you find out.

 

[Randy Holmes-Farley]

I tried 1M solution at 16 bed volumes (~2gallons solution) circulating through my own DIY 'RO Canister' type holder with a MJ pumping the solution through the GFO. After 96hrs I started the rinse process. I'm 30 gallons of RO/DI rinse water in at this point and still measure a pH of 10. Is anyone else rinsing this much and/or see a pH spike when placing the less rinsed media into the tank?

I figured if I still had a pH above the rinse water, there was still OH in solution with PO4 bound to these ions. Hence, no pH difference to RO water results in no PO4 in solution.

Am I missing something?

Unbuffered water at pH 10 does not have all that much ability to impact seawater pH.

It would be have 30 times less impact than limewater. So very roughly, adding 1 gallon of that water to 100 gallons of seawater would be expected to boost pH by much less than 0.1 pH unit (I calculate about 0.02 pH units).

 

[DeathWish302]

Unbuffered water at pH 10 does not have all that much ability to impact seawater pH.

It would be have 30 times less impact than limewater. So very roughly, adding 1 gallon of that water to 100 gallons of seawater would be expected to boost pH by much less than 0.1 pH unit (I calculate about 0.02 pH units).

Thanks Randy!

That gives me a little more reassurance I'm ok with my excessive rinse to this point. After that chem 101 final, I ran like the wind as that branch of science was interesting black magic after stoichiometry.....:eek1:

If I did want to tax my analytical side, where would you find a logarithm for such pH calculations?

 

[Randy Holmes-Farley]

There are a number of ways to figure this, but limewater has a pH of 12.5 and has a hydroxide concentration of about 0.0408 M. I also know experimentally that adding 1.25 volume percent of limewater boosts tank water pH by about 0.6 to 0.7 pH units.

pH 10 hydroxide solutions have a concentration of 0.0001 M. That's about 40 fold lower than the limewater, so the pH effect will be about 40 fold lower. Rough calculating, but good enough to know the pH boost would be small from a pH 10 hydroxide solution.

 

[DeathWish302]

There are a number of ways to figure this, but limewater has a pH of 12.5 and has a hydroxide concentration of about 0.0408 M. I also know experimentally that adding 1.25 volume percent of limewater boosts tank water pH by about 0.6 to 0.7 pH units.

pH 10 hydroxide solutions have a concentration of 0.0001 M. That's about 40 fold lower than the limewater, so the pH effect will be about 40 fold lower. Rough calculating, but good enough to know the pH boost would be small from a pH 10 hydroxide solution.

Thanks Again Randy.

I figured it was involved with the stoichiometry and smoke would roll form my ears....
I'll take your observations and run with it.

 

[reefdiy]

Will this work?

Will this work?

Since this post is still very active and filled with great advice and knowledge I would love ask if this product would work for regenerating GFO.

http://www.homedepot.ca/product/crystal-drain-opener-450-g/981198

The MSDS for this product can be found here:

http://www.lawrasons.com/pdf/lawrasons_jansan/rotyme/rot_crystaldrain_en.pdf

From the MSDS:
SECTION II - HAZARDOUS INGREDIENTS
Ingredients CAS # Wt% ACGIH-TLV LC50/LD5
1) Sodium hydroxide 001310732 50-80% TWA: 2 (mg/m3) Not available
2) Sodium carbonate 000497198 15-40% Not available. ORAL (LD50) mg/kg: Acute: 4090 (Rat)

I know that 100% sodium hydroxide is what I am after but I can not find Rooto Drain Opener or Roebic Crystal Drain Opener locally but this product is available here (Alberta, Canada) and for only about 3 dollars per 450grams.

I am wondering if the 15-40% sodium carbonate (aka Water Softener) would cause any problems. I expect that this product will be of a reduced efficiency because of the percentage of NaOH to Na2CO3 in the solution and that it might be hard to produce 1M NaOH batches with this product.

Any thoughts?

-Thanks

 

[Randy Holmes-Farley]

It is hard to know. It will probably work. GFO has some affinity for carbonate/bicarbonate, and that might come into play here as well.

 

[DHyslop]

I'm running a regen experiment right now. A few quick questions:

I'm using HC GFO and after two days the NaOH solution is still pretty clear. I was expecting the color to brown a little bit based on what I've seen here and elsewhere. Is this evidence that I've made an error, or does the HC GFO hold up this much better than the cheap stuff?

Also, do you guys neutralize the stuff before you put it down the drain, or just run it real slowly with a lot of cold running water? I haven't done the math yet but I figure it would take quite a bit of vinegar to neutralize. On the other hand the stuff probably doesn't need to come all the way down to 7 to be safe enough to dispose of.

Thanks

Dan

 

[nanojg]

Does a half a cup lye to a gallon of water sound about right? Thanks!

 

[nanojg]

Does a half a cup lye to a gallon of water sound about right? Thanks!

Maybe it was too much? It turned to mush

 

[MGM_]

Nano..Did you run it for more than 96 hrs? The high capacity GFO holds up much better.

 

[nanojg]

About 80 hours

 

[bheron]

Awesome thread. This might actually be the tipping point that keeps me in this hobby . I have about 260g total volume and just purchased 7 gallons of HC GFO for $174. Not sure I can do that again I have a GFO reactor from Bulk Reef Supply and also have the Roebic 100% product at my local lowes. Very excited if I can regen this $174 of HC GFO over and over!!

Anyway, my only question is: can my GFO reactor be used for ALL 3 steps? in other words, do I even have to take anything apart? Can I:

1) Take my Reactor with used GFP from my sump and drop it into a bucket of water/acid or water/vinegar. Turn on pump.

2) Take it out of that bucket and drop it into bucket of water/sodium hydroxide. Turn on pump.

3) Take it out of there and drop it into a bucket of RODI for final rinse?

Seems like that easy. Just not sure if steps 1 and 2 would damage my pump?

 

[DHyslop]

It seems to depend on the pump. People have had issues with the Maxijets and 1M solution. I've run several trials now with a Mag 5 and that seems to be holding up well. This weekend I'll be scaling my regen operation up to four reactors and a Pan World pump so we'll see how that goes.

If you have seven gallons of the stuff you might consider getting another reactor that you can dedicate to regen. That way you'll have GFO in the tank 24/7 as opposed to 3 days on/3 days off.

Also, if you're going to be doing much of this start getting your NaOH off the internet. Search for biodiesel or soapmaking suppliers. A lot cheaper than the Roebic.

 

[bheron]

Ah good stuff. Good points. Actually, i mis-typed. I have 7 "pounds" (1 gallon).

My reactor has a real whimpy maxijet 1200 on it. i might have some spare pumps I can mod to fit it so thanks for that idea.

I can get 2lbs of Roebic at Lowes for $12-$15 I think. How much will I need for a single canister of HC GFO? (havent done my math yet but I think thats about 350ml of GFO?)

I'd really like to just use the same setup and move it into and around different buckets.

 

[fishpoop]

Why rinse the lye out with RO and not tap water? Is it just to keep the PO4 from the tap water out?

 

[Buganddoug]

Okay I need some help and I am sorry for the questions.
I have about 20 pounds of Brightwell FerroxiPhos-G GFO that I need to regenerate. I just got a TLF PhosBan Reactor 550 with a Maxi Jet 1200 and Roebic Crystal Drain Opener.
I will be filling the reactor with 750grams at a time. How much Roebic Crystal Drain Opener should I use and how much water will I need?

Next set of questions.
Brightwells GFO was dry in the container. Should I dry it back out or put it back damp?
If I store it damp in a sealed container is that Okay to do?

Thank you for your help with my questions.
Daniel

 

[bertoni]

I'd store it after drying it out or in an unsealed container, to avoid any odor from any residual organics, but I'm not sure how much difference it'd make.

I don't know how much drain cleaner it'd take.

 

[tmz]

FYI, Post #181

It is sold wet by many companies. Not sure if there is a reason for that, but I can at least imagine that if you dry it out, small pores may close as the water leaves them, and may just not reopen on rehydration. In any case, I can't see any advantage to drying it.



__________________
Randy Holmes-Farley
Club 65535

I store it wet in covered plastic coffe cans with about an inch of ro water over it.

 

[tmz]

Here is post 182 and 183:

Would drying it out before storing it be advisable?
I plan to put mine into a sealed container and keep it until I need to rotate gfo in use . It'll be stored for at least a month. If I store it moist should I worry about bacteria, etc?



_________________
Tom

Randy's response: No it won't go bad.