Cob corn in an EKO

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Duetech

Minister of Fire
Sep 15, 2008
1,436
S/W MI
Limited test results have been done as the cob corn supply has been short. But 20% (est.) ear or cob corn has burned well in my EKO40. Using a bed of coals from wood as the starter base (don't start easy otherwise) the corn ignited and gasified well. A blue flame was quick to appear after a short time with the corn on the coal bed and little ash residue in the secondary after a complete burn. The corn will dry on the stem, as long as the ears turn downward, to a desirable MC percentage without needing any special drying facilities. No specific storage facilities will be needed as long as you don't mind hand picking or hand pruning (shucking would not be needed) otherwise arrangements would be needed for larger quantities. Full load burn time is about 6 hours max at zero degrees F. and very little wind and the boiler comes up to heat fast because the fire is hot early (blue flame at 120*f boiler temp). A few chunks of oak or other high btu/dense wood will extend the burn time. Loading is pretty easy with a bucket or frustrating by hand. Transitioning between wood and corn and back is as simple as whatever you choose to throw in next. Some would think it expensive but not if you have the place and experience to grow it. But it could be time consuming. For those who run out of good dry wood for whatever reason cob corn could be a very reasonable choice if you can come up with a low cost supply or need an emergency alternative fuel. I'm gonna try to grow a half acre next summer. If things go/grow half way well it should be about equivalent to 2 cords of 20% 21-24 million btu wood.
 
Thank you for the update - how much would a 1/2 acre of corn cost if you owned all the equipment? I guess seed wise
 
sdrobertson said:
Thank you for the update - how much would a 1/2 acre of corn cost if you owned all the equipment? I guess seed wise


Shannon I bet you have your dad lookin for a picker now right?? You cant cut down his corn he planted for them deer!!!!! LOL

Sometimes you can get 1 year old roundup ready seed corn for cheep at tha local mill. It will plant about 4ac if I remember right.


Rob
 
Lots of people rent out farmland to local farmers. Seems to me you could get them to throw in a few acres as part of the deal.
 
sdrobertson,
I can't quote you today's seed prices but the suggestion for buying year old is not a bad idea as well sometimes the bags break and they will allow you to nominally "sweep" up a savings that they would otherwise take as a loss. When I hobby farmed (80 acres) seed usually came in 75-80,000 kernel bags and fields were often planted at 28-33k per acre for the higher yields. If you are in an area that a farmer is planting you might want to check with them also as they might have some left over they would rather sell you than have you buy something that may cross pollinate with their corn. Otherwise the old way of getting seed might mean finding some cob corn for sale and hand shucking the seed from it. Bag corn sounds better already. I already have a small garden tractor with a cultivator so I won't probably spray my plot but sprayers can be rented or re-invented if you are inclined. I would rather sit on the tractor and "weed" than slap the bugs and wipe the sweat in the woods when it is 75f and up. There is a thread concerning a garn and cob corn. If you do a search on "cob corn" it will come up and give some insight to yields and ratios and btu potential. It prompted me to find some cob corn and try burning it. It might be too much effort to be valid for some but the way corn grows almost guarantees (weather permitting of course) a supplemental dry fuel supply that can offer a less than strenuous exercise in the process.
 
Thanks guys,
I'm mostly just trying to figure out how much corn it would take for a season as this was quite the discussion at work. I like the wood and hopefully will try peach pits also. The corn seems like it could be a good stand-by in a pinch and if for some reason the corn prices bottom out in the yet to be determined world economy.
 
http://forum.iburncorn.com/viewtopi...0&postorder=asc&highlight=grow+corn&start=120

Here is an old thread the chats about growing your own - what it took and what it cost

or just plug in a few terms like grow and cost on the site and you will find more

Just like wood -- you will need a corn crib to dry the cob corn - some old guys say it takes as long to dry cob corn so the moisture content is great to burn - as wood!
 
That's one helluva an idea considering I already own a JD two row planter for my wildlife plots! On second thought, I'd have to figure out a way to keep the wildlife out. :)
 
twofer said:
That's one helluva an idea considering I already own a JD two row planter for my wildlife plots! On second thought, I'd have to figure out a way to keep the wildlife out. :)


Do like I do I shoot them!!!! I just bought a JD grain drill and I own a jd 4 row planter. I just have to get the picker and I would be all set.
 
I am a farmer and have considered this as an option. I actually got interested in solid fuel heating by looking at LDJ's corn burners. The major obstical to me seems that I thought to myself how cheap I could really grow corn. I found that I was not thinking about it with the right prespective. Sure, if I had 1 acre in my back yard in with allowable access by a small tractor/plow etc, I could grow corn (rent-free) for near $2.50 a bushel. Just 2 years ago I would have been rich if I could get $2.50 a bushel even if I was paying rent but times have changed. Never-the-less, what I should have been thinking was how much I could SELL that corn for, plus not have the hand labor of picking the ears. If I can sell for $3.50 and then buy wood/propane wouldn't that be a 40% gain? Plus no labor? The other consideration is storage of ear corn. Unless picked near 15% MC you'd have to store it in a bin where air could flow thru it. One last comment. If anyone has picked up ear corn out of the fields while combining, you know how hard it is to pickup very many. My 2 boys go out with me for fun and pickthem up near the end rows and it takes a VERY long time to fill even 1/4 of my pickup truck. I can not imagine even picking 1 acre of ear corn (~175 bushels=9800lbs+cobs). I'd bet that would be al least 5-6 full pickup loads. Just my two cents.
 
Before things get into too grand a scale. Corn left standing in a field will not have to be stored as it can be considered "stored" as it stands. Shelled corn needs to be around 15% for corn burners but 20% burns well when on the cob in my gasifier plus the cob burns too. If corn is picked and shelled at or near 23% it has to be dried and that is a cost but that is thinking "production" large scale and not small and personal use. Corn in the field can be picked when the temps are low and moisture in the corn will be low too. To cut costs a 100 lb bag of feed corn can supply all the seed you need for several half acre plots. Here we have a deer season to help curb critter crunching but obviously there will be some predation. Over all the intent of this thread was to bring awareness to another source option for some especially for those who might be fighting high MC in their wood as some did/have been this winter. Also my wife can't really be considered an alternative wood splitter but she can be considered capable of picking corn (don't gasp she knows I said it). As far as labor is concerned cutting and splitting wood in the summer or winter has always caused me to break a sweat but I think 15 minutes splitting wood or picking corn will probably bring about the same btu yield but picking corn can be a casual approach at collecting btu's (2-3' or plus snows not withstanding). I have most of the equipment and the ground where I can potentially/passably grow corn for fuel, to supplement my wood, with a potential yield near two cords of wood on a 1/2 acre for around $100.00 or less with a small garden tractor but not if I "geek" at production output. I have been using about 5 cords of wood for the season and would not be able to grow corn to replace that without spending more than what wood would cost. We all work for our money and we all want it to work for us. There are some very reasonable and accurate statements made in this thread about growing and storing corn so it should not be looked at in a casual sense but also bear in mind there are options that can be very economically viable for adding more types of fuel for home heating too.
 
This last year would not have been a good year here to have left the corn standing in the field. The fields that the corn had high moisture that the farmers didn't pick in the fall was PICKED CLEAN by the deer. I had over 35deer in the field next to me every night. They cleaned the field fast. They will travel for miles to find standing corn. It was a good thing for the deer as the snow and temp was bad and in places that there wasn't food they had a hard time. I don't think you should count on haveing any corn left if you don't pick it by late fall. The deer and turkeys will clean it. As a kid I helped hand pick corn and I went out this year and picked two rows that was left for my donkeys and it takes a long time to pick. Wood is faster. Now if you are at an auction and happen to find some cheap cob corn that would be different.
One other thing. Storing cob corn in a corn crib will bring EVERY mouse and rat from miles around. I remember on the farm that we had Thousands of mice and rats when we would tear out the cribs in the spring. And our twenty or so barn cats were so fat they only would catch the easy ones. The rats would have tunnels dug under the cribs and raise up the boards. I don't think corn is in my future
leaddog
 
Just Curious has any one tried choping standing corn later than normal at aprox the same m/c that you guys are using with just cobs and burning it stalk and all? maybee you would call this dry silage?
 
I have heard of people bailing cornstalks for use in an OWB but I think the corn itself had already been harvested.
 
Corn is one option. Switchgrass is another. Switchgrass can be pelleted, bricked or pressed into log shapes. Switchgrass can be grown on poorer ground and thereby keeps the good land for growing food like corn. It is high yielding, perennial and requires fewer inputs than corn (cheaper per ton).

Fast growing renewable biomass crops are important alternatives to wood burning in gassers, but leaching chlorine out of the fuel is a precaution that should be utilized to prevent corrosion.

Switchgrass, allowed to overwinter in the elements, is safe for boilers because the chlorine is reduced by snow and rain. Can't comment on corn, but I would expect the same would be true.

I'm planting 11 acres of switchgrass for mushroom substrate this year. When the mushrooms have done their thing with the switchgrass, and after I've tried to make moonshine (ethanol); I'd like to use that biomass in the boiler. It won't be cheaper than wood and may be marginally more work, but it will solve a disposal problem.
 
Mushroom Man,
I rally know very little about chlorine in corn or grasses but isn't there also chlorine in wood?
 
There is chlorine in wood but in much lower concentrations than fresh cut switchgrass. Recent studies have recommended leaving the crop standing through winter. An alternativeis to mow, windrow and leaving the crop until spring before baling.

This approach is unconventional but brings chlorine levels down to the levels found in wood.

I would check with corn specialists before burning large amounts of unsenesced corn. Why take the chance with your boiler?
 
On the surface I think corn is okay chlorine wise as there are many corn burners and boilers in use but checking is a good idea. For the switch grass and leaving it wind row-ed until spring in my area I think I would just have semi composted mulch for the corn patch by the time it got dry enough to bail and burn and though pelletizing would make a manageable consumer product it makes for another complexity unless you could go commercial. Or doesn't switchgrass breakdown that quickly?
 
Two growers that I have met with (200 acres and 60 acres respectively) have dealt with the high chlorine issue differently. One bales in the fall and leaves the bails out in the weather. His level of chlorine is at a questionable level. The other cuts the crop 5" high and windrows leaving the crop on top of the stubble. He has had good success with spring baling. It dries very thoroughly and makes competitive pellets to wood but 200 btu/pound less heat and more ash. Personally, I'll never use pellets. They are just too expensive to produce.

I have seen bio-bricks. The bio-bricks I have seen are either conventional clay brick shape or hockey-puck-like with a hole (like a donut). They are cumbersome to produce too.

If I go the route of burning switchgrass, the fuel will be home-made synthetic logs made with an adapted woodsplitter (to squeeze out the water). Again, it only makes sense for my situation after the mushrooms have broken down the cellulose and ethanol has been extracted. If a decent price can be attained for the spent mushroom substrate from gardeners, then I likely won't bother with the other steps in my attempt to go full-circle.

Corn has been a viable heating fuel for centuries and remains one; but I think the grasses might provide a lower cost alternative while keeping corn for food. Food producing land is getting valuable since there is no more being made and populations just keep expanding.

I would not be terribly surprised if fast growing C4 perennial grasses like switchgrass and miscanthus became popular feedstocks for gasification and electrical generation in an oil starved future.

If large masses of consumers started to use gasifiers, wood might get scarce. Biomass from perennial grasses could fill an important role in the supply channel much as wood pellets have filled a niche in the wood stove heating market.
 
Mushroom Man,
That is interesting about the switchgrass. Do you have information that tells you what the tonnage yield is per acre and what would be the likely btu output per ton? If btu output is equal the concept of acreage whether in corn or switch grass would seem moot because we are still talking agricultural usage for yield output so if corn could produce more or equivalent units of energy then corn would be a better choice on average and for overall usage. In areas where soil erosion is a major concern and growing seasons are limited and or not as productive as corn then grasses would be a hands down superior product. Alfalfa and clovers are/can be high protein crops that might be viable when compressed into pellet or block form but I have not heard of any studies in that direction. As far as mass gasifier usage is concerned rubber is one of the highest btu fuels for gasification but it is not likely be something the consumer would have access to but energy companies could utilize the technology.
 
Cave2k said:
Mushroom Man,
That is interesting about the switchgrass. Do you have information that tells you what the tonnage yield is per acre and what would be the likely btu output per ton? If btu output is equal the concept of acreage whether in corn or switch grass would seem moot because we are still talking agricultural usage for yield output so if corn could produce more or equivalent units of energy then corn would be a better choice on average and for overall usage. In areas where soil erosion is a major concern and growing seasons are limited and or not as productive as corn then grasses would be a hands down superior product. Alfalfa and clovers are/can be high protein crops that might be viable when compressed into pellet or block form but I have not heard of any studies in that direction. As far as mass gasifier usage is concerned rubber is one of the highest btu fuels for gasification but it is not likely be something the consumer would have access to but energy companies could utilize the technology.
 
What is the problem with the chlorine with the boiler?

On a side note, I was looking for the answer to the above question and I ran across web sites on how to make "pine straw" bales - which are apparently small bales of pine needles that people use for mulch. This got me thinking - they are really dry, could be p/u and baled tightly and I bet you would get good heat if you threw a small bale on top of a good coal bed.
 
Yields with switchgrass depend upon so many variables, that you could compare it to getting maximum efficiency from a gasification boiler. Lots of variables and a continuum on each variable.

I have read about expected yields from 12 T/acre to as low as 4 T/acre. In my area, 5-6 tons/acre seem reasonable. Take your hay yields and double the mass and that would be a reasonable expectation.

Switchgrass will grow 12-15 years from one planting.

Another exciting biomass, very popular in Europe is miscanthus x giganteus. It yields double what switchgrass yields and can grow to 13 feet tall. Reports out of Illinois field trials show 12-16 t/acre. It will grow for 25-30 years. A major downside for me is that it is planted from rhizomes instead of seed. There are no dedicated planters that I have seen here in Canada or the USA, so customizing existing equipment would be required. I have not been able to locate any suppliers of the rhizomes who have stock either.

Switchgrass and miscanthus will both suffice for our mushroom substrate.

The chlorine issue was enunciated by a Dept. of Energy (USA) research team member at a recent switchgrass conference in Guelph Ontario. The unsenesced grass cut and harvested in the fall and processed soon thereafter had 5 times the chlorine of the senesced (left out all winter) grass. Apparently the chlorine when burned in a low oxygen environment leads to a highly corrosive substance being produced. That is all I know about the chlorine issue. Chemistry is not my forté.
 
I missed the question about BTU/ton. It is approximately 200 btu/pound less than wood so I'd guess 7800 versus 8000. So, 2000*7800*[tons/acre]=btu/acre. Assuming 6 tons that is 93.6 million btus/acre. Double that for miscanthus.

I think these grasses are an exciting prospect for energies of the future; especially if one can extract use from them before burning them.
 
Mushroom man,
I am just quetioning your yields on switch grass. Even 6 tons per acre seems very large. I have raised alfalfa/grass hay out here on our very highly productive soils. With basic fertilization you can expect 5 to 7 actual tons @ 15% mc per year. Alfalfa/grass hay is MUCH more dense than the prairie grasses. Prairie grasses are more "reed-like" and hollow, similar to wheat and oat stubble(straw). One man can ride and stack behind the baler when we do straw. There is no way one man would want to be on the wagon by himself all day when we do hay. In addition, unlike hay where we cut and it regrows 3 to 5 times a year (every 28 days) the prairie grasses would only get one cut in the fall with no regrowth. I have a CP-25 mix on 95 acres on my home farm and have considered baleing up some (taking the gov penalty) to make hunting lanes and provide cattle bedding, but never have the time in the fall. My guess is comparable yields would be slightly better than wheat/oat yields at probably 3-4 tons per acre.
 
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