My plan to was to do an uncontrolled burn of equal volumes of old and new K, measuring:<UL TYPE=SQUARE><LI>weight before burning
<LI>weight after burning
<LI>temperature over time from lighting to stone cold[/list]No lids, no vent settings, no meat, no water. Just a flat-out burn to determine visual and temperature differences.
I put together two identical burn rigs. Each consisted of a pan holding a wire mesh charcoal ring attached to a charcoal grate. I weighed each rig in advance so that after the burn I could place the whole thing, ashes and all, on the scale, subtract the weight of the rig, and calculate the net weight of the ashes.
I used a metal coat hanger to fashion an armature that clipped to the edge of each pan to hold a bead probe over each fire at 15" above the empty grate.
I hand-selected 100 briquettes of old and new K, making sure to get full briquettes--no broken pieces or chipped corners allowed.
The batch of new K weighed slightly more than the old K from my stash from last fall. Not sure if this was due to the age of the old K or just a manufacturing variance between old and new. (By volume, new K is supposed to weigh less than old K).
Old K: 6 lbs, 1/4 oz (96.25 oz)
New K: 6 lbs, 2-1/4 oz (98.25 oz)
In order to get things burning quickly and evenly, I measured 2 oz. of Kingsford lighter fluid into a spray bottle and sprayed it evenly over the old K until empty, then repeated with 2 oz. on the new K.
I plugged the two probes into the data logging thermometer and lit the coals.
Within a few minutes, the thermometer started beeping "low batteries." Damn it. I thought they were going to be OK, but apparently not. I disconnected the unit, put in fresh batteries, and reconnected.
Started getting weird temperature readings. Only 70*F over the old K, while 200+ degrees over the new K. The flames were burning high off the coals and had fried the old K probe. There goes my ability to do a well-documented temperature comparison for this burn. I took the probe off the new K so as not to fry the second probe.
So, I just watched the fire progress visually. It was very obvious that the new K lit a lot faster than the old K, the fire spread across the top of all the coals much quicker, there was more flame and higher flame on the new K, and the intensity of the fire was greater. It looked hotter, especially in the center of the fire--it had a more intense orange color than the old K.
Things continued this way for the first couple of hours, with new K looking hotter than old K. I used a Fluke probe that I know is good to 1800*F and took some spot measurements by hand. At one point, I got a pretty consistent measurement of a 30*F difference in favor of new K.
I also tried an infrared thermometer that goes up to about 800*F, but when aimed at the center of both fires it registered "OL" for overlimit--too hot to measure.
After about 3-1/2 hours, the new K looked cooler than old K, and the probe confirmed this. But at 4-1/2 hours, even though both fires were in decline, the new K was again burning hotter. Perhaps there was some ash building up and falling away that accounted for the difference.
I tried the infrared thermometer again and now got "OL" on the new K, but 770*F on the old K. So new K was running hotter by some unknown number of degrees F.
Here are some photos I took at 4-1/2 hours, at about 3:30am this morning.
Photo #1 shows old K on the left, new K on the right. The camera was set for no flash and a twilight setting, which forces the shutter to stay open longer. There is some ambient light from a porch light above and to the right. These photos are Photoshopped together to appear side-by-side. In real life, they were about 2 feet apart. You can see that the new K definitely appears to be burning hotter.
http://host79.ipowerweb.com/~virtualw/new_kingsford/old-new1.jpg
Photo #2 is the same as #1, but using no flash, an automatic shutter setting, and no porch light.
http://host79.ipowerweb.com/~virtualw/new_kingsford/old-new2.jpg
Photo #3 uses the same camera settings as #2, but from a distance of about 20'. You can see the difference in intensity between old on the left and new on the right, even after 4-1/2 hours. This photo is Photoshopped together and cropped, which makes it appear closer than the 20' where I was standing.
http://host79.ipowerweb.com/~virtualw/new_kingsford/old-new3.jpg
I went to sleep and checked on things at 6:30am. The new K was stone cold. The old K looked cold upon first inspection, but still had some heat and just a bit of orange color in the middle.
By 10:00am everything was cold. Here's how much ash resulted:
Old K: 1 lb, 2-1/2 oz (18.50 oz)
New K: 1 lb, 1-1/2 oz (17.50 oz)
Old K: 19.22% ash (18.50/96.25)
New K: 17.81% ash (17.50/98.25)
I'm bummed that I wasn't able to log the temperatures. Not sure if I'm going to get some new probes and try this uncontrolled burn again, or just go straight to testing in an empty WSM. Probably the later.
Regards,
Chris
<LI>weight after burning
<LI>temperature over time from lighting to stone cold[/list]No lids, no vent settings, no meat, no water. Just a flat-out burn to determine visual and temperature differences.
I put together two identical burn rigs. Each consisted of a pan holding a wire mesh charcoal ring attached to a charcoal grate. I weighed each rig in advance so that after the burn I could place the whole thing, ashes and all, on the scale, subtract the weight of the rig, and calculate the net weight of the ashes.
I used a metal coat hanger to fashion an armature that clipped to the edge of each pan to hold a bead probe over each fire at 15" above the empty grate.
I hand-selected 100 briquettes of old and new K, making sure to get full briquettes--no broken pieces or chipped corners allowed.
The batch of new K weighed slightly more than the old K from my stash from last fall. Not sure if this was due to the age of the old K or just a manufacturing variance between old and new. (By volume, new K is supposed to weigh less than old K).
Old K: 6 lbs, 1/4 oz (96.25 oz)
New K: 6 lbs, 2-1/4 oz (98.25 oz)
In order to get things burning quickly and evenly, I measured 2 oz. of Kingsford lighter fluid into a spray bottle and sprayed it evenly over the old K until empty, then repeated with 2 oz. on the new K.
I plugged the two probes into the data logging thermometer and lit the coals.
Within a few minutes, the thermometer started beeping "low batteries." Damn it. I thought they were going to be OK, but apparently not. I disconnected the unit, put in fresh batteries, and reconnected.
Started getting weird temperature readings. Only 70*F over the old K, while 200+ degrees over the new K. The flames were burning high off the coals and had fried the old K probe. There goes my ability to do a well-documented temperature comparison for this burn. I took the probe off the new K so as not to fry the second probe.
So, I just watched the fire progress visually. It was very obvious that the new K lit a lot faster than the old K, the fire spread across the top of all the coals much quicker, there was more flame and higher flame on the new K, and the intensity of the fire was greater. It looked hotter, especially in the center of the fire--it had a more intense orange color than the old K.
Things continued this way for the first couple of hours, with new K looking hotter than old K. I used a Fluke probe that I know is good to 1800*F and took some spot measurements by hand. At one point, I got a pretty consistent measurement of a 30*F difference in favor of new K.
I also tried an infrared thermometer that goes up to about 800*F, but when aimed at the center of both fires it registered "OL" for overlimit--too hot to measure.
After about 3-1/2 hours, the new K looked cooler than old K, and the probe confirmed this. But at 4-1/2 hours, even though both fires were in decline, the new K was again burning hotter. Perhaps there was some ash building up and falling away that accounted for the difference.
I tried the infrared thermometer again and now got "OL" on the new K, but 770*F on the old K. So new K was running hotter by some unknown number of degrees F.
Here are some photos I took at 4-1/2 hours, at about 3:30am this morning.
Photo #1 shows old K on the left, new K on the right. The camera was set for no flash and a twilight setting, which forces the shutter to stay open longer. There is some ambient light from a porch light above and to the right. These photos are Photoshopped together to appear side-by-side. In real life, they were about 2 feet apart. You can see that the new K definitely appears to be burning hotter.
http://host79.ipowerweb.com/~virtualw/new_kingsford/old-new1.jpg
Photo #2 is the same as #1, but using no flash, an automatic shutter setting, and no porch light.
http://host79.ipowerweb.com/~virtualw/new_kingsford/old-new2.jpg
Photo #3 uses the same camera settings as #2, but from a distance of about 20'. You can see the difference in intensity between old on the left and new on the right, even after 4-1/2 hours. This photo is Photoshopped together and cropped, which makes it appear closer than the 20' where I was standing.
http://host79.ipowerweb.com/~virtualw/new_kingsford/old-new3.jpg
I went to sleep and checked on things at 6:30am. The new K was stone cold. The old K looked cold upon first inspection, but still had some heat and just a bit of orange color in the middle.
By 10:00am everything was cold. Here's how much ash resulted:
Old K: 1 lb, 2-1/2 oz (18.50 oz)
New K: 1 lb, 1-1/2 oz (17.50 oz)
Old K: 19.22% ash (18.50/96.25)
New K: 17.81% ash (17.50/98.25)
I'm bummed that I wasn't able to log the temperatures. Not sure if I'm going to get some new probes and try this uncontrolled burn again, or just go straight to testing in an empty WSM. Probably the later.
Regards,
Chris
