On Jul 24, 2010, at 11:57 PM, doug.williams wrote: > Hi Brian and Gasification Colleagues, > > It's not always easy to be correct when you analyse these flares, and you > need to tell us more about how you are burning the gas after it leaves the > gasifier. > > 1. Is it first cooled
Yes. Our producer gas goes through a water cooled heat exchanger. The temperature of the product gas by the time it gets to the flare pipe is close to if not at ambient. Our immediate post-heat exchanger TC indicates that the gas right out of the heat exchanger is a bit below ambient but, to error on the side of caution, I'll state with some assurance that by the time it hits the flare outlet, it is most certainly below 100F (38C). > and cleaned of dust and moisture? Mmmm, sort of. Straight out of the gasifier shell, the product gas goes through a GEK cyclone. Then it goes through the above described heat exchanger. So the cyclone clears out whatever it does. Then the hard temperature drop in the heat exchanger, we assume, crashes out a lot of moisture which we assume collects in the heat exchanger's sump. Right now, the next key point is the flare outlet. However, we intend to have a 40 micron filter between the heat exchanger and the flare. We HAD one in there but our first couple of efforts were, shall we say, "suboptimal". (We could also say, "downright ugly".) The "tar" we made looked and stuck like asphalt, I'm pretty sure we could have resurfaced some streets with the gunk we made! Given that, the 40 micron filter element was destroyed. The filter housing is still in-line and we have a replacement element in hand, but we're a bit leery of our own incompetence and have not yet been bold enough to install the new element. > > 2. If not,what temperature is the gas at the exit point of the gasifier? > > 3. Are you able to control the amount of combustion air going into the burner > nozzle? Do you mean the flare pipe? Or do you mean the air input manifold inside the gasifier? If you mean the flare, I don't really understand the question, but I'll guess the answer is "no". If you mean the air input manifold in the gasifier, then the answer is, "control, sort-of, monitor, yes". Our initial design included both "push" of input air and "pull" of producer gas. We're using an air compressor to push the air into the gasifier. We were also using a blower to pull the product gas just before the flare. For several reasons, we concluded the pull wasn't needed and we've deleted the blower so now we only push the air into the gasifier. I'm not entirely happy with our fine control of that flow. We have coarse control, but not fine. I'm intending to shop for an additional regulator to give us fine control this upcoming week. We do have a standard mechanical (Dwyer) float flow meter at the air inlet of the gasifier so we can manually read/record our air input volume/time. > > 4. What temperature is the flare exhibiting from the probe I saw you using in > the flare? Humph. I don't like that TC. Seems pretty much pointless to me. The slightest puff of breeze and the flame is anywhere BUT on that TC. Even when the air is still, the flare dances around so much that I don't believe the accuracy of the readings we get from that TC. But the numbers from the time of the afternoon video were anywhere from 260 - 650C (500 - 1200F) and at the time of the night video were 480 - 650C (900 - 1200F). But I have close to zero confidence in the quality of that data. > > 5. Can you feel a stinging type of radiation from the flare if you place > your hand or face close up? Goodness, I have no idea! I'll check that next time we run, though if it is all the same to you, I'll use my hand, not my face! -brian > > ------------------------ > Greg has already offered some examples of the possible answers, but there are > other factors to influence the flare behaviour, which can be narrowed down > for your specific gasification flare experience that you share with us. > > Doug Williams, > Fluidyne Gasification. _______________________________________________ Gasification mailing list [email protected] http://listserv.repp.org/mailman/listinfo/gasification_listserv.repp.org http://gasifiers.bioenergylists.org http://info.bioenergylists.org
