Vaporising Oxyalic Acid Against Varroa

[alldigging]

That says to me vaporisation is allowed.But only once per year.

Could anyone sensibly afford to treat any more often?

A vey precise (well, only to 0.1g and not to the nearest 0.01g like some would deem necessary) with no reference to the size of the enclosure or even the colony. 10 000 bees in winter in a single deep National or 40 000 bees towards autumn in a double brood box.

If you buy the big packet then it's about 50p a hive which is cheaper than MAQS, and other non-winter methods.

It is just very much dearer than buying a bag of oxalic acid.

But provides you with a product number for your hive records.

 

[MikkoN]

Oxalic acid has two water molecules attached to each oxalic acid molecule.

When heated:
Water of hydration leaves at 101.5° C then water boils off leaving anhydrous oxalic acid crystals
At 157° C the oxalic acid starts to sublime (goes directly from solid to gas)
At 189° C the oxalic acid which has not yet sublimed decomposes to formic acid and carbon monoxide
Leaving usable temperature somewhere between 105-150°C.

The VARROX-vaporiser reaches temperatures of up to 300°C. Start from cold, heats up to too high temp, not so great tool...
With that I wonder how much oxalic acid chrystals there are in the air (in the hive) and how much turns into formic acid? This amount of formic acid is not even near the required amount for varroa control.

But vmVaporizer on the other hand is undoubtedly way better tool if you can control the airborne chrystals i.e. keep them in the hive where they belong! Their marketing video was frightening to watch.

This from vmvaporizer page made my day: "Vaporizer will revolutionize the way you deal with varroa mites, moths, mice, rats, and all kinds of other pests that interfere with your beekeeping business."

Oh well, which ever way the mites get killed, the end result is what matters.

Trickling does exactly the same, applying takes less than a minute per hive, doze per hive costs the same and is way safer to use (or at least requires less protective gear) -> my choice.

btw. how much does that vmVaporizer cost?

.

 

[Erichalfbee]

The VARROX-vaporiser reaches temperatures of up to 300°C. Start from cold, heats up to too high temp, not so great tool...
With that I wonder how much oxalic acid chrystals there are in the air (in the hive) and how much turns into formic acid? This amount of formic acid is not even near the required amount for varroa control.

From the youtube video of how to operate this vaporiser

irwin harlton 2 months ago

can you tell me what temperature you treat , vapourize at, I see you start at 550
Reply ·


Lukas Thanei 3 weeks ago
+irwin harlton you start at 600 °C to heat up the vaporizer. Then you set it to 300 °C and have to wait about 2 minutes before you start the treatment.

 

[Hivemaker.]

how much turns into formic acid?

Non would turn to formic acid if used as instructed, in fact it would be very difficult to produce formic from oxalic, unless using a pressurized device.

 

[MikkoN]

Hivemaker, I'm not a chemist but after a quick read I understood that in high temps oxalic sublimes and decomposes. Maybe got it wrong and should read further...


Erica, I didn't check the YouTube clips, but I think those posters should read the instructions
www biovet ch/en/images/stories/products/Varrox/PDF/Varrox-Verdampfer pdf (sorry for the format. newbies can't post links)
the correct procedure is roughly this:

- Apply oxalic acid onto a cold tools as I MUST NOT vaporise before put into hive and seal up the hive ~30sec (my estimate)
- After the hive is sealed up, the vaporiser should be connected to a car battery (12 V) for 2 1/2 minutes
- After disconnecting the VARROX®-Vaporiser, wait for 2 minutes before the appliance is pulled out, so that the oxalic acid-vapour can settle down.
- Once removed, ensure that the entrance of the hive is shut tightly again and left shut for another 10 minutes.
- After taking out the VARROX®-Vaporiser, it should be cooled in a bucket of water, so that with the next use, no vaporisation begins before the appliance is inserted into the hive
With this written procedure we are doing good job keeping the oxalic acid chrystals inside the hive.

This adds up to 5min minimum per hive. Plus the 10min seal time but during that you can proceed with the next hive...

Total 15min before one hive is done. I can do my 10 hive yard in less than that with trickling, with same results - mites dead!

But I can see VarroX attractive if you are into gadgets.

And sorry for wrong information earlier -> The VARROX®-Vaporiser starts from cold but reaches temperatures of up to 400°C.

 

[Hivemaker.]

Hivemaker, I'm not a chemist but after a quick read I understood that in high temps oxalic sublimes and decomposes. Maybe got it wrong and should read further...

There have been a few threads on this subject, this is one which discusses it, but on a different forum.

http://www.beesource.com/forums/sho...ipe-method&highlight=oxalic+vapor+formic+acid

 

[jenkinsbrynmair]

Total 15min before one hive is done. I can do my 10 hive yard in less than that with trickling, with same results - mites dead!

Nonsense - four and a half minutes total vaping time, fifteen (maybe thirty if you're a bit slow) seconds to fill, put the varrox in place and less to remove it so let's say five minutes per hive, we can disregard the ten minutes settling time as it's taking place whilst others are being done - the final hive's ten minutes takes place whilst you are packing up anyway so, unless your hives in one apiary are ten minutes walk apart it's five minutes per hive with a leeway of thirty to sixty seconds let's say for faffing around.
Are you telling me you can remove a hive roof, crack the seal and remove crown board, trickle, replace crown board and roof ten times in less than six minutes?
Same results, yes, a bit more time maybe, accepted, but no major disturbance of hive, no unnecessary exposure of the cluster to cold and no work for the bees re-propolising the seals. and proven, less of a risk of compromising the queen if multiple treatments are necessary.

 

[MikkoN]

Whilst waiting my flight to depart I had a quick look:

MSDS (material safety data sheet) for oxalic acid dihydrate
Boiling Point: 149 - 160C (300 - 320F) Sublimes.
Melting Point: 101.5C (216F)

To me it says that usable temperature for our mite control purpose would be between 101.5C and 149 - 160C

Passing first point, melting, the water boils off and oxalic chrystals are airborne, this is good.
When passing boiling point it sublimes and then the desired end result is lost, bad.

On chemicalforums-dot-com the question was asked
" The "truth" that is often said is that if heated over the sublimation temp. the oxalic acid will break down into formic acid and carbon dioxide, BUT that can't happen in an open heating situation (I.e. the hot open top pan). So here is my question:

Can Oxalic acid break down/degrade into formic acid and CO2 in an open heating pan or will it just vaporize/sublimate in the oxalic form?"

and the admin answered:
"That definitely looks to me like a plausible decomposition path, but not necessarily the only one - CO2, CO and H2O look as reasonable products as well."

So based on this quick check, I'd say temperature control in crucial when vaporising oxalic as once decomposed to which ever format, we have lost our oxalic chrystals

Some smoke coming from under the crown board does not guarantee successful mite control vaporising

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[Hivemaker.]

Some smoke coming from under the crown board does not guarantee successful mite control vaporising
.

Put some water in an open pan and boil it, keep boiling and check the temperature after 20 later, will it be hotter than boiling point.

If you have smoke coming out the top you are burning the acid, but it would of sublimated long before it would burn, so is therefore a non issue.

 

[jenkinsbrynmair]

MSDS (material safety data sheet) for oxalic acid dihydrate
Boiling Point: 149 - 160C (300 - 320F) Sublimes.
Melting Point: 101.5C (216F)

Sublimation is the transition of a substance directly from the solid to the gas phase without passing through the intermediate liquid phase, Sublimation is an endothermic phase transition that occurs at temperatures and pressures below a substance's triple point in its phase diagram. The reverse process of sublimation is desublimation or deposition, in which a substance passes directly from a gas to a solid phase.

Which is exactly what we want - sublimation disperse the OA throughout the hive and desublimation deposits it on all surfaces (including the bees)

Passing first point, melting, the water boils off and oxalic chrystals are airborne, this is good.
When passing boiling point it sublimes and then the desired end result is lost, bad.
.

Nonsense

To me it says that usable temperature for our mite control purpose would be between 101.5C and 149 - 160C

.

No to the first temperature range, we want it between 149 - 160C but you miss a simple point - the higher 'undesirable' temperatures only exist on the pan - the rest of the hive will be at about 34 degrees Celsius or less. when the OA reaches 149 - 160C (the temperature we require) it sublimates, leaves the horrible hot pan and disperses throughout the hive depositing itself on the bees when it desublimates THE DESIRED RESULT
This smack a bit to me of the Finnish obsession with trickling the hives rather than any scientific thought.

 

[MikkoN]

I come in peace...

As I said earlier I'm not a chemist but surely have learned a lot today!



I'm saying what I wrote - that at my beeyard it won't take longer than 15min to trickle 10 hives.

I try to keep it simple so majority of my hives consist of bottom, hive body, sheet of plastic and roof.

Take off roof, take off plastic, trickle, put back plastic, put back roof and we are done. Maybe one minute each.

I repeat trickling after cleansing flight early march or so.

Could probably do it in less than six minutes if I had my wife helping me, for sure!


I haven't seen major disturbance to my hives and admit that cluster is exposed to cold for a while but I don't see negative impact, normal winter losses for me are around 5% (including queen losses).

Colonies differ with their propolising urge, but maybe my italians are different to your bees as they don't propolise that much and frames are not glued together so bees are visible. Also when I tear off the plastic it does not break anything and putting it back is no issue.

To me the most important in trickling is to make open roof cold exposure as short as possible. This way the bees don't fly at all.
And I do trickle also in sub-zero temperatures, but keep the oxalic under my jacket to keep it warm.



It seems that I don't have the priviledge being treated as an individual but just as another Finn...

Well, despite of all I wish you all a happy new year!

.

 

[Hivemaker.]

I'm saying what I wrote - that at my beeyard it won't take longer than 15min to trickle 10 hives.
.

With the Sublimox you can potentially sublimate/treat 30 hives in that time, although 20 is more reasonable, and all without opening the hives at all, but speed is not an issue with most beekeepers anyway.

 

[jenkinsbrynmair]

It seems that I don't have the priviledge being treated as an individual but just as another Finn...

.

No offence intended MikkoN, just making sure of a structured argument around the subject, some of your fellow countrymen don't take heed of new science but demand we accept their mantra and not move on

 

[MikkoN]

Thanks for clearing this up jenkinsbrynmair, I'm OK.

This must be a hot topic...

We are living in different climate so maybe different methods are required. Our 3 month brood break compared to your couple of weeks?

Hivemaker. - to me speed is an issue when trickling : don't want to have bees flying out and my fingers are freezing!

.

 

[jenkinsbrynmair]

We are living in different climate so maybe different methods are required. Our 3 month brood break compared to your couple of weeks?

Ooooooh I think I may have to use that quote elsewhere. Glad to have a Fin confirm we have different climates

But yes - brood breaks are one issue for us, that's why vaping has become more attractive, as even if we don't get a brood break we can vape three times over a three week period to zap all of the mites. It's starting to look like replacing thymol treatment for a lot of us as it's far cheaper if you have a fair number of hives.

 

[madasafish]

It's starting to look like replacing thymol treatment for a lot of us as it's far cheaper if you have a fair number of hives.

Yes. Such a no brainer that even I am a convert...

 

[Finman]

.
I have teached 10 years varroa killing to British beekeepers, and that had not been easy. I have not invented myself nothing. I have just told what others do and what has been researches.

And these teachings have been in BBK letters too, before I have written anything about those.

I have not written anything wrong. I know, because I have researched.

 

[Finman]

.
We are living in different climate. That is not explanation. I take advices from Australia, Nz, Canada, (not from UK), from USA and so on.

Everyone adapt his learnings to their own beekeeping.

British beekeepers live on same climate and they use amazing variety of varroa treatment.

British bees stand much more different beekeepers' styles than in our country, because our weather does not forgive so much as warm British Isles.

 

[jenkinsbrynmair]

.

British beekeepers live on same climate

Maybe someone needs to take lessons in climatology?

We are living in different climate so maybe different methods are required.

.

 

[Finman]

Maybe someone needs to take lessons in climatology?

It is enough, when I know where I live. You take care yourself. Climatology lessons do not bring more honey to hives. Vain knowledge in beekeeping.