Low temp burners?

[Fransisco]

I've got a low temp burner running on a 20,000 bu oats bin. It came off around 20% a couple of weeks ago and is no way close to dry yet. I'm wondering if I'm doing any good keeping the burner going when the outside temps are so low to begin with.

[cchurch]

The burners will raise the intake air temperature by about 4-6°C, but more importantly they make the intake air dryer, so that it will dry your grain faster.

I have some electric ones that draw 37.5 AMPs at 240 V, 9000 Watts.

9000 Watts = 30708 BTU.

So my electrics ones are the equivalent of yours.

[Fransisco]

That's what I was thinking. That even though the temp isn't much the humidity should hopefully be low enough that things will dry. Even if it is slow.

[cchurch]

I just looked at Edwards grain guard and they say 60,000 BTU up to 100,000 BTU.

My electric one is 30,000 like I said before, but one thing that I don't understand is:

When you burn the propane, you get water vapor and carbon dioxide, so I wonder if the propane combustion is actually working against the drying process.

For every 74.4 grams of propane burned, 72.08 grams of water vapor is produced.

[cchurch]

Correction to last sentence:

For every 44.08 grams of propane burned, 72.08 grams of water vapor is produced.

[hedgehog]

the grain on top dries last, can you turn it into another bin?

[nicolaas]

the warmer the air, the more moisture carrying capacity the air will have (increased dewpoint) which will remove more moisture from the grain. In my experience, unless you can get the temmp at air inlet into the 20's with low humidity, not much drying will be done. It should though keep your grain from rotting to quickly at that moisture content.

[TOM4CWB]

sisco,

Did 1500bu of soft white wheat... from 19% and ended at 12% after 2 weeks.

The Edwards eng. said that it drops about .5% per day... if the average temp can be kept above 10 deg C. Our average temp was about 5 deg C most of the time.

The top 200 bu out of 1500bu was still about 16% on the cone peak... it should have been leveled for even drying.

5hp fan... 100,000btu NG burner... 2 weeks non-stop day and night. THe bigger the burner... the dryer the bottom gets... it needs to be mixed is an obvious conclusion. Cooled bin without heat on last 3 days.

If it is 20,000 in one bin... chances are you can't get the 4-6 deg c without a huge burner... if average isn't above 8 deg c... it simply exponetially decreases drying by about half every 4 deg down in temp I am told. Below freezing ave temp I am told will not dry grain.

The temp rise of 4-6deg C... allows far more moisture to be removed... than the burner nat. gas produces in producing the temp rise.

Key... needs to have average temp ABOVE 10 deg C for effective drying.

[TOM4CWB]

Fransisco,

Just removed yesterday from the flat bottom full floor 19 foot air bin. Wheat was only about 10 ft deep on sides. 5 deg was average outside temp... plus the 4-6 deg increase in heat the 100,000btu NG heater provided.

I couldn't find larger burners for big bins that are made. Edwards is thinking about making something for next year.

U trough hopper air tubes (with bottom open) I am told are near useless and often burn out burners. The air has trouble easily getting through the grain... (trying to go back through the fan) he also said rockets work well for even drying and good flow.

Open the top lid... if there is not good air flow out the top... watch out for burner damage. Also you should have water running off the inside of the roof onto the ground... if it is drying. Good luck if it is too cold... big ice problems!

[Fransisco]

At some point I'll have to try turning it but right now bin space is a premium and I'm not done yet. 10 degrees during the day is doable so far but it does drop lower at night.

Was told not to turn it off as the drying front can crust in the middle of the bin. But had to(not a big enough electrical service to run everything) so as to dry some beans. A couple of days later we fired it up again and the air is still blowing through so I think we got lucky and maybe it's drier than we think.

Not fun, all this juggling but at least everything is slowly getting binned.

25% left to combine.

[poorboy]

Have a look at the Air-o-matic sold in saskatoon. It is furnace style heat exchanger that puts the exhaust back to the atmosphere and has a thermostat on it. Runs on nat gas or propane.

I have used it quite a bit and really like it. Buy a big model and you will be able to dry in any condition. A couple of years ago I dryed canola at -20C and it worked well.

You can adjust the thermostat so that not as much heat is needed during the day when humidity is lower and increase the temp during the night. Average dry occurs in most bins in about 4 or 5 days, but this is severly overdry grain in the bottom and tough grain on top. If you run another 5 days you have the whole bin severly overdry and then you just mix it with a bin of tough grain.

The air-o-matic is sold by air-o-don in the green book and is expensive, but a very worthwhile addition to any farm, especially so as we are moving into the colder months.

[saskcanfarmer]

Has anyone used a forced air unit? We just rented one today. 350,000 BTU. Runs on diesel. Gonna give it a try on a good drying hopper bin we have. 19' 5000b bin. We have filled it half full. 3.5hp fan. Anyone has any experience with them? Temperature was 52C going into the fan.

[poorboy]

Forced air unit should work fine. Make sure you have enough air flow with your fan as you want to be able to get the moist air out of the roof. If the fan is too small the air will start to condensate and ice up on the roof when the temps are below freezing.

Too hot an incoming air may burn the grain kernels. I personally would not go above 100degF as we have had many days is Aug and Sept where the grain gets that hot and there is no damage. Prolonged blowing on grain in the 50degC range I have no first hand experience with, but doubt it would help much.

The idea of adding heat is to cut the humidity down. For every 20degF you add, the humidity gets cut in half. So if the air is 30degF and 100% hum, you add some heat and make the incoming air 50degF it will be 50% humidity and if you go to 70degF air it will be 25% humidity and 90degF air will be 12.5% hummidity. The equilibrium for canola is something like 2.5% for air that is 90degF and 25% hummidity. All that will happen by adding any more heat is that you will severly overdry the bottom layer of grain in the bin. It will not speed the drying up much.

If you have a thermostat on your heater, you could try turning it down some. If you have a bigger fan you could try it, as more airflow would make the incoming air cooler. Or else you could see if the rental place has a 200 or 250,000 btu heater.

[ColevilleH2S]

[ColevilleH2S]

Oops that should read 45°F/27°C not º. I got my DOS and Windows codes mixed up.