Lockwood Bio Fuel bricks

[Danno77]

Pretty much your usual looking bricks. Stamped LBF on the side of the bricks. Claims that one 4'x4'x3 pallet is equivalent to one cord of wood.

Was at my "Farm and Home Supply" and they had them labeled at 5.99 a pack (20 bricks = net 35lbs), so I threw three packs into a cart (I've been wanting to try them out).

Went to check out and as I look at the receipt right now i see that one pack was 4.79 on sale, and the other two were normal price. I might have to see if they have some weird special going on now, or what....

anyway, wonder if I can buy them in bulk. I might look into it, but certainly don't intend to replace my regular firewood, especially not at these premium prices.

I'll report back after I burn them...

 

[Danno77]

ok, ran a few armchair numbers. about 60 packs (60x20=1200 bricks) makes up their "Cord Equivalent." at 5.99 per package, that's $360 for a cord equivalent. Around here that's as 2-3 times as much as CSS mixed hardwood delivered.

Also, this equates to 2100lbs of product.

 

[Duetech]

Interesting figures since btu's come from the poundage of the wood. Maybe they're thinking pine when they say cord. I see literally tons of wood chips and saw dust being thrown in to a land fill pit and wish I had a way to compress it into bricks. Like you though I prefer the cord wood as provided by the trees as the best economical source of heating the home.

 

[Danno77]

Interesting figures since btu's come from the poundage of the wood. Maybe they're thinking pine when they say cord. I see literally tons of wood chips and saw dust being thrown in to a land fill pit and wish I had a way to compress it into bricks. Like you though I prefer the cord wood as provided by the trees as the best economical source of heating the home.

Yeah, definitely has to be fir, pine, aspen, cottonwood...
I won't be buying much of this stuff unless there is a huge sale, or if something significant happens to me ability to process or even buy firewood.

 

[NextEndeavor]

Just for fun, I tried the Menards version today: "Gren Heat". Same 38 pound, 20 block bundle. They are heavier than my cord wood per volume that's for sure and claimed 17,000 BTUs per block. At any rate, they burn fine but way more $ than I have in my free wood. My wood warmed me three times before going into the stove too.

 

[Danno77]

So, can I load the stove full of these things? I estimate that I can probably get almost the whole 60 bricks in there.

 

[NextEndeavor]

Not sure about running a full load all at once, better control the air in! FYI: I lit off 4 bricks at 7am with some tinder. At 9 am added two more bricks. Thats not much fuel for such a large firebox. By 1 pm, still had plenty of coals but stove top was down to 325. In summary, 6 bricks maintained around 500 degrees about 5 hours. Running cord wood the rest of the day now.

 

[begreen]

I noticed a box of Tacoma bricks at the local hardware store and had to try them. They are 3lb, moderately compressed bricks, 8 to a box. While convenient, I was unimpressed. As is typical of these lower compressed products they expand a lot with heat and burn up pretty quickly. At $9.99 a box I thought they were a poor value. There are much better products on the market if one has to use compressed wood for heating.

 

[Danno77]

Anybody else think that these things look a lot like Pez? I want a giant dispenser next to the stove.

 

[weatherguy]

I bought 10 packages for $2.99 at TSC, I use them to burn down coals when they get too high, that way I still get good heat while Im burning down coals. Like Bg said, theres some really good compressed logs if I want to burn some for a load.

 

[NextEndeavor]

The brand I tried (see above) did very well. The ceramic glass viewing window remained clean so they must be plenty dry. Couldn't say that for my wood last year but fine this year. These compressed bricks advertise low ash and I witnessed "almost" no ash for the 6 hour burn. But, due to cost and processing enjoyment, I'm sticking with cord wood.

 

[Danno77]

Ok, just throwing some numbers out there because I'm sitting in the recliner with nothing better to do.
I weighed one brick. It was 1lb 14oz. If there is 8600btus per pound of actual wood, then each of these suckers are holding like 15,000 BTUs (I subtracted a little for minimal moisture) per brick
Let's say I can fit 48 bricks into my stove. That would be 720,000 btus loaded in there. Let's also say that the EPA claims the burn range of my stove is like 12k-28k BTUs per hour. Doesn't that mean, that if I run at high temps it would take me 720,000/28,000 or over 25hours to burn through it?

Doesn't that also mean that 15 bricks or so would get me an 8hr burn at high end or 6 bricks for 8hrs at the low end?

If I test it out, who thinks these will come even close?

 

[sheepdog000]

Ok, just throwing some numbers out there because I'm sitting in the recliner with nothing better to do.
I weighed one brick. It was 1lb 14oz. If there is 8600btus per pound of actual wood, then each of these suckers are holding like 15,000 BTUs (I subtracted a little for minimal moisture) per brick
Let's say I can fit 48 bricks into my stove. That would be 720,000 btus loaded in there. Let's also say that the EPA claims the burn range of my stove is like 12k-28k BTUs per hour. Doesn't that mean, that if I run at high temps it would take me 720,000/28,000 or over 25hours to burn through it?

Doesn't that also mean that 15 bricks or so would get me an 8hr burn at high end or 6 bricks for 8hrs at the low end?

If I test it out, who thinks these will come even close?

WOW! Are you serious? That is just way too much math for me this late at night. I'm going to bed, my brain hurts........ :cheese:

 

[Fifelaker]

Anybody else think that these things look a lot like Pez? I want a giant dispenser next to the stove.

You now owe me a keyboard Oh sh9t it$ ztart(n& T@ G8 n#w.

 

[Wood Duck]

I bought some of those things and was going to burn them but they split worse than elm. Never again.

 

[NextEndeavor]

Hay Danno, anxious to hear how your "real life" test goes with a full load. I can't afford that many bricks. Like some other products the disclaimer usually reads, "actual results may very" or, "specifications may change without notice". Probably the case here too. The Menards site http://www.menards.com/main/plumbing/heating-cooling/fuel/wood-fuel-blocks/p-1712204-c-6855.htm reports 17,000 BTUs per brick, each nearly 2 pounds.

 

[spirilis]

Ok, just throwing some numbers out there because I'm sitting in the recliner with nothing better to do.
I weighed one brick. It was 1lb 14oz. If there is 8600btus per pound of actual wood, then each of these suckers are holding like 15,000 BTUs (I subtracted a little for minimal moisture) per brick
Let's say I can fit 48 bricks into my stove. That would be 720,000 btus loaded in there. Let's also say that the EPA claims the burn range of my stove is like 12k-28k BTUs per hour. Doesn't that mean, that if I run at high temps it would take me 720,000/28,000 or over 25hours to burn through it?

Doesn't that also mean that 15 bricks or so would get me an 8hr burn at high end or 6 bricks for 8hrs at the low end?

If I test it out, who thinks these will come even close?

Haha I'd like to see 48 of those bricks fit inside a stove...
(disclaimer: I've use these types of products almost exclusively in my pre-EPA woodstoves for 2 seasons, which is supplemental heat for the most part)
Keep in mind they (talking about compressed sawdust bricks made in an RUF Gmbh briquetting press, which most of these ~2lb to ~8lb bricks all are) expand, typically to ~2x their size. That would be one hell of a load. My guess is your stove would either overfire and put out more than the EPA's stated BTUs, or they'd offgas so fast your secondary burn tubes wouldn't be able to burn all the smoke and you'd lose a lot of the heat. Plus one thing I've noticed is you need to space the bricks out properly to get them lit, you can have big masses of bricks but there should be areas for oxygen to flow. You might have luck stuffing it good on a pre-established coal bed though. And actually packing them tightly without too many air gaps is key to making the mass burn slower.

But with a burn tube system and the bricks stacked pretty high w/o overshooting the stove's secondary air input capability, it just might get the kind of burn times you're calculating, so long as the primary air is shut down all the way. My experience with the Jotul 8 (pre-EPA, no cat) is that they offgas and produce vigorous flames and awesome heat for a short hour or 2 then smolder, albeit slowly and with a gentle let-down of the heat, but with noticeable smoke coming out the chimney. An insulated firebox with refractory baffle over burn tubes should get the most out of these since the late-cycle smoldering will burn cleaner. Maybe a cat would work well too, I don't know (anyone with a cat stove experiment?)

 

[Danno77]

I did read that they expand. I wonder how much. Maybe I'll throw one into the oven to get a MC reading on it, and I'll do some measuring, too. I tried poking it with my MM an it just read 00%...

 

[spirilis]

The "WoodBrickFuel" stuff I burn (2lb/brick) will usually expand to almost 2x size and burns fast, the "Eco Energy Fuel Blocks" (8lb/brick) burns much slower and expands some but usually not all at once, i.e. it expands and burns steadily, so the brick "migrates" to the far sides of the firebox as the side facing the fire burns away but the side expanding expands outwards. The latter is made exclusively of oak and seems to be compressed "tighter" or maybe it's just the smaller size of the sawdust bits, the woodbrickfuel looks less compressed/is composed of larger wood chips. The oak "Eco Energy Fuel Blocks" actually do "coal" up unlike the WoodBrickFuel which smolders/pyrolyzes almost all the way down to ashes.

I think both of those bricks I burn mention somewhere around ~6-10% moisture content. There is no contiguous grain with these bricks like there is with cordwood, so I'm guessing the moisture meter won't work properly. That fact also defines some of its burn characteristics IMO. The RUF briquetter's site mentions the product takes on some burn qualities of Coal, to which I believe they really mean low-rank coal like Lignite which is often formed/compressed into briquettes too. What it tends to mean is that the brick burns like peeling an onion--the outer surface releases what little moisture it has, pyrolyzes, burns to charcoal-dust then ashes all in a gradient before the sawdust below it burns. Hack apart a burning brick that's partially expanded with your poker, the inside will be tan and look untouched (but quickly catch fire). Because the burning pieces are actually tiny bits of sawdust, they tend to produce some fly-ash just like coal although it doesn't migrate up your chimney from what I've seen, just collects on the side of the stove along with the soot. This burn process will accelerate a bit if the brick expands (exposing the inside of the brick more), and while there is no "grain" like cordwood there is a "compression grain" I guess you could say which lays perpendicular to the axis by which it was compressed. The brick most often falls apart into separate segments along that "compression grain" as it expands. For the larger, 8lb briquettes, if you want to break them down into smaller bricks you pretty much have to split them across that "compression grain" and I have played with that here and there with a splitting axe. It's not an exact process and often produces rather strangely shaped logs with "noodled" bits of sawdust-brick wedges and a bunch of sawdust all over the floor. Sometimes I get lucky and split them straight in half, split down the long axis (so you have 2 long, slender pieces of brick). It's helpful for making smaller fires.

 

[Danno77]

should be seen as merely an "initial views" kind of post. reading too much into this would be like giving too much credit to somebody's first impressions of a stove they've never used before.

First test (Moisture content).
I placed the brick into the oven at 230F for about 12 hours and then weighed it. It had dropped from a total of 30oz to 28oz. I baked it for another 8 hours. Same weight. so we'll assume that the bricks are at least 6% MCwb or 7%MCdb, really dry either way you look at it.

Second Test (expansion).
I then placed the brick back into the oven at 450 for about 3 hours. I could tell I was loosing some volatiles, but that was irrelevant for what I was looking for. The heat did seem to cause the brick to break free along some compression seams (i don't know a better way to label it), but held together fairly solidly. I did not take measurements, but i think it's safe to guess that it grew about 5% along each axis. Not much, but noteworthy. Assuming that actual burning would be necessary to validate the minimal growth, I tossed it into my hot firebox and let it burn. It did grow some more in there, I'd say 10-15% along each axis, but as it burned some mass was burned off and part of that growth was ash left just attached, but not solid mass. (Like, if I pulled the brick out and blew the ash off of it, it would no longer be 10-15% larger than it was, but more like the 5% I initially saw.)

Third Test (Burning)
In order to maximize the burn time of these bricks I thought a completely flat top burning down would keep the lower bricks from burning, but I was too chicken to make a perfect "rectangular prism" because it would have taken more than one package (minus that one brick for testing)

So, I made three layers in something of a pyramid (See the first arrangement below). I had cleaned out the coals and ashes from the stove so as to be able to tell how much ash these produce, so I planned on starting this fire top down by placing some big coals on the top two bricks. Perhaps the stove had cooled too much to ignite this way, but I was completely unsuccessful in getting it to light like that. SO, I proceeded to arrange a few bricks inside to make a little "house" for the coals on the top. This way did seem to work much better, but I found out quickly that having a roaring fire on the top surface of the exposed bricks was insufficient to carry the draw when I shut the door (even with the primary wide open). I eventually gave up and place ONE split of pine (approximately 16" long and what would equal 1/4 of an 8" diameter round) on the two bricks that sat out front on the lowest level. this one log completely changed the burn characteristics of the entire load. Within a minute I had every exposed surface glowing (but not open flames) and the split itself was flaming. As I shut it down I noticed some good secondaries rolling at the top.

The overall burn time of this load probably came out near 8 hours WITH that split mixed in. From the doghouse it ate a tunnel straight through the middle of the pyramid an as that tunnel completely burned the pyramid in half, the burn efficiency dropped significantly and I had to mess with the primary air several times through the nite. This morning it was easy to restart the fire from the crumbling, yet glowing bricks that were left.

SO: my overall impression is that the natural cavities and overlapping logs that are in a normal fire facilitate a good long term fire with flames. With these bricks it is very difficult to burn them in a geometric pattern with few spaces. I guess one could equate this method to trying to get one huge chunk of dry firewood to burn top down. it just isn't going to work well.

I think that these bricks would be better off tossed all willy-nilly in there, but I think it's pretty safe to assume that you can get 8 hours of meaningful heat from them, but it takes fiddling with the air to do it.

These definitely seem like they would be appropriate to supplement with wet cordwood, or used as several bricks at a time on top of hot coals, but systematically packing the stove with them doesn't seem to be conducive to getting long even burns like I've been able to do with cordwood. As I said before, though, this is preliminary. I'd like to try to master it before I condemn them for being a good complete substitute for cordwood (burningwise only, i'll not get into financial feasibility or the benefits of storage, availability and mess)

edit: forgot to add the picture:

 

[spirilis]

Good notes! Yeah I've never had any luck starting wood briquettes by massing them together, I always start them with some kind of bottom-up "teepee" formation, and for startup purposes I often put a slat of pallet wood on top (preference) or more wood bricks. Typically a quarter supercedar in the middle of the teepee and some charcoal briquettes flanking it on either side, plus the wood bricks do need some space between them to get air in there -- especially important as they start expanding in the middle of the teepee and close off those gaps.

Laying them as a mass with "tunnels" between them works when reloading on a coalbed with a warmed-up stove.
I think I am going to start taking pictures of my setups and post them so folks know what I'm talking about. These are tricky to ignite when starting with a cold stove.

edit: Here's a sketch & camera pic of my typical "6 brick startup fire":
woodbrick-startup1.800.jpg
I put a quarter supercedar in the middle of that teepee before laying it down and sometimes a charcoal briquette (cheap Sam's club crap) flanking it on either side to help intensify the startup inferno. The bricks on the end are optional, I've put folded sheets of aluminum foil in there before. Could probably use a small chunk of firebrick too. Just something to keep the heat from escaping the inside of the teepee, but not too restrictive as to block smoke & flame from coming out (plus that provides an exit for the oxygen entering the teepee from the gap between the middle bricks).
Also the pallet wood on top could be replaced with 2 wood bricks if you are so inclined...

 

[NextEndeavor]

Great experiment! I'll keep some of these "Giant Pez" on hand just to have but will stick to my cord wood 99% of the time. Appreciate the time you put into the testing. Another Menards product I tried was "Uncle Ethan's Fire Log". These are about 3.5 inches diameter and 12 inches long. They are a compressed wood deal too but with larger fibers and don't feel as dense or heavy. I used one and it really expanded a bunch then fell apart and burned quicker. You won't get as much BTU per volume with these and the price was actually a little higher for less product total weight.
Crazy, isn't it, the stuff we do for entertainment ...... Gonna be a long winter of fun feeding the stove.

 

[Trex83]

Hello guys, I was wondering if someone could give an update on the thread? I am looking to tryout different biomass sources in a downdraft gasifier, primarily looking at briquettes or other type of brick made from agricultural residues or grown crops.
Thanks for the help,
Trex83

 

[smokinj]

What kind of btu output you getting? i know that could be a tough one but hows it compair to a good hardwood? Would you run them on a 0 degree night? (High winds of course)

 

[firebroad]

I bought a lot of biobricks from TSC last year. Like the reference to PEZ, they do look like that! Anyway, Like spirilis said, you have to give them some air spaces. I never used the teepee configuration, but I would put two or three amongst the splits, never right together. If you put them too close to the front, they will swell up and possibly fall against the glass--not a good thing, as once they are burning they are not solid enough to move without falling apart.
I think of them as giant pellets, I am sure they are the same material. They seem to produce a lot more ash, a soft beige-ish color. They do burn hotter, but also burn shorter, in my opinion. As far as the price is concerned, yeah, they are a lot more expensive the cordwood, but how much would you pay for the mythical "well seasoned and ready to burn" stuff?