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  • Hello Asad, I hope to finalize my design for a medium sized reactor ( 20-40 litres) over the holidays and begin construction in January. Having abandoned the idea of using electric heater bands in favour of propane, Im now considering using kerosene.
    I recently distilled some of my crude fuel and it contains 35% kerosene. Economically it makes sense to use this as my heating source. I can easily obtain a central heating kerosene burner which delivers up to 25kilowatts of heat.
    I like the idea of delivering the heat via an inner metal tube but am unsure how to do it with a kerosene burner. Have you any suggestions?

    Comment


    • Responces, catching up

      Tony; Have you made any rough calculations on the yield from running a batch with a 1500 Lb bale? Seems to me thats going to produce a lot of vaporous gas, in addition to the liquid fuels. Would be a waste, if you don't have sufficient capacity to STORE said vaporous fuel, once produced.
      Its because the vaporous fuel is produced in such large quantities, and takes so much space to store, that I am contemplating using a "oxcygen concentrator" to compress it at higher pressures. I've seen the inside of one; basically, it is a series of compressors, with each piston and cylinder slightly smaller than the one before It takes aptnospheric air, compresses it in the first cylinder, and then feeds THAT compressed air into the next ylinder, to compress it a little more, and then on to the next, etc. Gets up to very high prseeures. At some point, (can't recall where in the process, now) it runs the 'air' thru zeolite, (I think it is) which apperently removes the nitrogen (I think it is), leaving oxygen under high concentrations. These are used for people with breathing proclems, such as COPD, so that they don't need to carry around an oxygen bottle every where they go.
      I regularly see these units selling on Craigslist here (US) for around $250. New they cost over 10 times that.Anyway, I'm HOPING this will enable me to compress the vaporous product from my reactor into a small enough area to be able to store it in a practical way. Any thoughts on this, anyone?

      Asad; yes, you are right in emphasising using new materials, not junk. I didn't think thru thoroughly before I posted, and was taking into account working on a limited budget. And by the way, it should be noted, in Texas several years ago, an oil refinery Blew Up, killing several people. So, even the PRO'S, using stainless steel, good welding, etc. can have bad things happen with this technology!

      Not sure we mentioned this, but I also think its a good idea to START SMALL; build a very small reactor first; just for experimenting; make your mistakes and go thru the learning curve with it/them, before trying to build a large unit, just makes sense to me. Anyway, thanks for the correction! Personally, I don't think you can be "Too Harsh" when it comes to emphasising safety. Better to hurt someones feelings, than have someone hurt or killed, because no one wanted to hurt their feelings by being blunt. I'm sure we all agree on that. Jim

      Comment


      • Imakebiodiesel

        Seems to me the basic design (for heating from within) would be similar, regardless of the method of heating; a reactor designed SIMILAR to the way a gas (as opposed to electric) hot water heater is designed; kind of like a 'stretched' donut. Or, a long cylindrical tank with a tube running thru it.

        If the tank is vertical, I should think having the tube run up the center of the cylinder would be appropriate, (again, just LIKE a gas water heater). Your kerosene or propane, oil or whatever) burner would be underneath the tank, and the tube running up the center of the tank would act like a 'chimney'. If the tank were horizontal, the burner could be inserted INTO the tube, somewhat, with air (to 'feed' the combustion) coming in one end of the tube, and the exhaust (from the combustion) going out the other end. In this design, I'm not sure whether the tube should be centered in the reactor, or running along the bottom, or at least NEAR the bottom. Also not sure if baffles or convolutions in this 'tube' would increase heat transfer.

        As I am contemplating this design, woud LOVE to hear anyones thoghts on this. By the by, to be a 'senior member' on this forum, doesn't mean you are 'more knowledgeable'; it just means you have posted a lot! Newbies shouldn't assume anything by the designation.

        I have a cartoon next to my computer, to remind me to always question anything I read, on the I-net; first frame shows a 20 something 'sexting', and in a bubble it shows him visualising who he's posting to, based on their description of themself; a 20 something female, who "looks like Bo Derek in that movie "10", only without the cornnrows". The second frame shows who he's REALLY 'sexting'; a 45 Y.O. potbellied, beerdrinking, cigar smoking MALE!

        I keep it their as a reminder, you never know who your 'talking' to, what their knowledge and motives are, on the I-net. Jim

        Comment


        • Reactor most not be vertical tube. Efect of air lift pump.

          Comment


          • Originally posted by dutchdivco View Post
            Tony; Have you made any rough calculations on the yield from running a batch with a 1500 Lb bale? Seems to me thats going to produce a lot of vaporous gas, in addition to the liquid fuels. Would be a waste, if you don't have sufficient capacity to STORE said vaporous fuel, once produced.
            Its because the vaporous fuel is produced in such large quantities, and takes so much space to store, that I am contemplating using a "oxcygen concentrator" to compress it at higher pressures. I've seen the inside of one; basically, it is a series of compressors, with each piston and cylinder slightly smaller than the one before It takes aptnospheric air, compresses it in the first cylinder, and then feeds THAT compressed air into the next ylinder, to compress it a little more, and then on to the next, etc. Gets up to very high prseeures. At some point, (can't recall where in the process, now) it runs the 'air' thru zeolite, (I think it is) which apperently removes the nitrogen (I think it is), leaving oxygen under high concentrations. These are used for people with breathing proclems, such as COPD, so that they don't need to carry around an oxygen bottle every where they go.
            I regularly see these units selling on Craigslist here (US) for around $250. New they cost over 10 times that.Anyway, I'm HOPING this will enable me to compress the vaporous product from my reactor into a small enough area to be able to store it in a practical way. Any thoughts on this, anyone?

            Asad; yes, you are right in emphasising using new materials, not junk. I didn't think thru thoroughly before I posted, and was taking into account working on a limited budget. And by the way, it should be noted, in Texas several years ago, an oil refinery Blew Up, killing several people. So, even the PRO'S, using stainless steel, good welding, etc. can have bad things happen with this technology!

            Not sure we mentioned this, but I also think its a good idea to START SMALL; build a very small reactor first; just for experimenting; make your mistakes and go thru the learning curve with it/them, before trying to build a large unit, just makes sense to me. Anyway, thanks for the correction! Personally, I don't think you can be "Too Harsh" when it comes to emphasising safety. Better to hurt someones feelings, than have someone hurt or killed, because no one wanted to hurt their feelings by being blunt. I'm sure we all agree on that. Jim
            Hi Jim, Great idea, but to be honest with you, I hadn't really thought that far ahead. I'm hoping that a friend of mine who is a retired engineer will be able to design something like you are describing. Unfortunately he is in poor health, so I don't want to bother him until he is feeling better.

            Comment


            • otpadnoulje

              Not sure I follow; why would a tank care what its orientation is, vertical or horizontal? Either way, as the plastic melts and releases vapors, the vapors are going to want to rise. I believe the petroleum industry uses vertical columns, for processing petroleum. Could you elaborate? Jim

              Comment


              • tony

                maybe for your FIRST reactor, you wanna start a little smaller, and work up to 1500 Lb bale per load capacity? At least you could get some idea on how much liquid and vapour is produced from 1 lb, and then use that to get an idea of how big of tanks you need to process 1500LB. I have this image of your processor producing this great, honey colored fuel, and its running all over the ground, and the vapour is being vented, because your holding tanks are too small! LOL.

                When they first came out with CNG vehicles, (compressed natural gas) you could only fill them at special gas stations. Then they came out with a home fueling station. it costs about $2500, and it takes the low pressure natural gas which runs to your house, (for hot water, cooking, etc. and super compresses it into a liquid. Vehicles need this, in order to be able to carry enough fuel to get a decent range between fill ups. Anyway, this 'unit' is a somewhat larger version of what I described, and it compressses the NG to the point that it becomes a liquid; I'm just trying to do it "On the cheap". Actually, NEW oxygen concentrators costs $2500-3500; its just I can get a 'used' one cheaper, and I don't see many "HOME CNG filling units on craigslist, although I DID see one awhile back, but they wanted new price for it.
                Anyway, I have a carbon fiber CNG tank, capable of handling the pressure, so thats my 'plan' for dealing with the vapour. Jim

                Comment


                • Originally posted by dutchdivco View Post
                  Not sure I follow; why would a tank care what its orientation is, vertical or horizontal? Either way, as the plastic melts and releases vapors, the vapors are going to want to rise. I believe the petroleum industry uses vertical columns, for processing petroleum. Could you elaborate? Jim

                  My experience!

                  Wmo, only. Vertical tube reactor. At the entrance of the condenser I've got oil, black oil instead of steam Air lift pump effect.

                  http://www.fao.org/docrep/010/ah810e/AH810E119.gif

                  You can see air lift pump when you open cocacola or cocking milk. Seethe!

                  Problem 2.

                  Evaporate any liquids directly depends on pressure. If you reduce pressure, increase the amount of evaporation.

                  We will look at two cases.

                  First: horisontal reactor, column height 10 inches
                  The total pressure is atmospheric pressure 400 inches + 10 inches static pressure = 410 inches

                  Second: vertical reactor, the height of the column 400 inches,
                  total pressure, 400 +400 = 800 inches

                  That's why:
                  VACUUM DISTILLATION, to decrease pressure.

                  Hope, this help!

                  Comment


                  • to Asad.
                    "The new reactor is just heated by hotair by tubes placed INSIDE the reactor, NOT outside ".
                    Is it not difficult to clean the reactor from carbon black with the pipes inside the reactor?

                    Comment


                    • I am quite new to this and must thank you for this knowledge. I can follow instructions well but, have basic technical knowledge. I can't thank you enough for this post.
                      Small minds talk about people. Average minds talk about events. Great minds talk about ideas.
                      http://www.renewablegreenfuel.com

                      Comment


                      • Alec

                        "to Asad.
                        "The new reactor is just heated by hotair by tubes placed INSIDE the reactor, NOT outside ".
                        Is it not difficult to clean the reactor from carbon black with the pipes inside the reactor?"

                        You DO hit on an issue, here, although I might say "challenging" rather than "difficult", but this IS something I'm wrestling with, myself.

                        Some thoughts; with heating tubes located inside the reactor, the carbon black that builds up on the inner surface of the walls of the vessel just acts like additional insulation; holding the heat in. Unlike a reactor with the heat source on the outside, where the build up would tend to (also acting like insulation) be BETWEEN the heat source and the plastic, and so need to be removed after each session.So, it might not need to be cleaned off after every session, in a design with the heat source INSIDE the vessel? Of coarse, over time as you got a build up of 'crust', it would reduce the volume of the reactor. And, any build up on the "heat tube" located inside the reactor WOULD, again, be counter-productive, as it would be between the heat source and the plastic, and would tend to interfere with heat transfer.

                        In order to explain my thinking, let me do it in a progression;

                        You have a tank which is LIKE a gas water heater; a cylindrical tank with a tube running thru the center. Visualise it as 'horizontal' rather than vertival as a water heater normally sits. You have 2 fittings, at least 2" in diameter, with a 'gate valve' on each, at opposite ends and opposite sides of the tank.
                        On one of the fittings you attach tha hose from a 'shop vac', with a screen over the opening. On the other, you attach a hose with a nozzle; turn on the vacuum, open the gate valve, plunge the nozzle into the shredded plastic, and 'fill' the tank. When your done, close the gate valve on the 'nozzle' fitting first, and create a negative pressure in the tank, then close the second gate valve, and turn off the vacuum.

                        Now your ready to run heat thru this central tube, to melt the plastic.When the processing is done, remove all lines attached to the tank. Lower a long piece of chain into the tank, thru one of these 2" fittings, and ROTATE the tank, on the 'axis' of this central tube. Could have a gear reduction motor to rotate it for several hours, if neccesary. The chain scrapes/ knocks loose all the carbon black on the sides of the tank. Then (heres the tricky part) find ome way to get ahold of the chain, and remove it from the tank. Attach the vaccuum, and suck out all the carbon black. Obvious problem; the chain wouldn't clean the carbon black on the outside of the central heating tube, unless as the cylinder rotated, the chain 'rode up' on the side, to the point that it fell in/back down, and contacted the tube.

                        So, have a 'mounting bolt', located in the center of each round end of the tank, which is sitting in a 'bearing', so the tank can rotate on them. Have the 'heating tube' located off center, out at the inner surface of the wall of the cylinder; when heating the tank, this would be located at the bottom. When rotating the tank to clean it, the chain would then come into contact with this tube, every rotation.

                        The advantage of this design, (if it could be made to work) is you wouldn't have any need for a 'hatch' which jetsis goes into considerable detail describing; and therefore no problem with getting an airtight seal, etc. The filling and the cleaning would be done thru these fittings. On the other hand, it DOES present challenges to design and build, and,...I'm not sure it would work!
                        Maybe I'm just making it too complicated? I hope I have described my thinking so others can follow. The only way to know for sure if it will work, is to build it and try it, i guess.Jim

                        Comment


                        • Inside heating tube reactor

                          Originally posted by Alec View Post
                          to Asad.
                          "The new reactor is just heated by hotair by tubes placed INSIDE the reactor, NOT outside ".
                          Is it not difficult to clean the reactor from carbon black with the pipes inside the reactor?
                          The first reactor I made few months back is quite similar to the water heater concept .
                          My reactor dia=25" & 64"height.
                          Having 04-tubes placed at equal distance running from bottom-Top . A gas burner placed at the bottom .
                          Gas burner could only heatup the reactor upto 175 celcius . So I have to wrap 05=electric-band heaters around reactor walls to take the temperature upto 450 celcius .

                          Now the coke depositing around the walls of the tubes started . I have to place another flange opening near the bottom in order to remove the deposited coke after couple of runs, this is a cumbersome process.
                          But you only learn until you do-it .

                          My second reactor
                          I just completed recently & will conduct trials nextweek .
                          I made this reactor having 24" dia with a seamless schedule 40-pipe .So I have to weld only the top & bottom . It can take more heat stress & about 4-times more pressure than a similar thickness welded sheet .

                          It has a special arrangement of tubes placed HORIZONTALLY inside the reactor . They are designed in such a manner that the Hot Air Hits them from the outside & inside the tube is filled with the molted plastic which heats up quickly , infact in half the time than my previous reactor .


                          Heating system I selected is a Gas-fired hot-air BLOWER-Burner .As used in the boilers .

                          The coking problem .
                          Yes U guys are right that if I completely pyrolyse the plastic it will soon jam the tubes completely .
                          So what I plan to do, is that Iam melting the plastic around 175 ceclius in this reactor & than transferring this molten plastic to the second reactor for cracking .
                          Hopefully no coking issue will come-up. & I plan to run 2-batches a day as my second batch will be already half-heated when it arrives in the main reactor for heating , so hopefully it should take half the time to pyrolyse .

                          Well this is all theory , lets see how it turns out to be .
                          I will try to post its pictures soon .

                          Comment


                          • Originally posted by dutchdivco View Post
                            maybe for your FIRST reactor, you wanna start a little smaller, and work up to 1500 Lb bale per load capacity? At least you could get some idea on how much liquid and vapour is produced from 1 lb, and then use that to get an idea of how big of tanks you need to process 1500LB. I have this image of your processor producing this great, honey colored fuel, and its running all over the ground, and the vapour is being vented, because your holding tanks are too small! LOL.

                            When they first came out with CNG vehicles, (compressed natural gas) you could only fill them at special gas stations. Then they came out with a home fueling station. it costs about $2500, and it takes the low pressure natural gas which runs to your house, (for hot water, cooking, etc. and super compresses it into a liquid. Vehicles need this, in order to be able to carry enough fuel to get a decent range between fill ups. Anyway, this 'unit' is a somewhat larger version of what I described, and it compressses the NG to the point that it becomes a liquid; I'm just trying to do it "On the cheap". Actually, NEW oxygen concentrators costs $2500-3500; its just I can get a 'used' one cheaper, and I don't see many "HOME CNG filling units on craigslist, although I DID see one awhile back, but they wanted new price for it.
                            Anyway, I have a carbon fiber CNG tank, capable of handling the pressure, so thats my 'plan' for dealing with the vapour. Jim
                            Jim, That's a good idea. I am assuming that if my friend is unsure about any of his calculations, we will be doing something smaller first. Unfortunately, I am not very tech or builder savvy, and will be relying on others. Also, I talked to a machinest with a cnc and he quoted me about $500 just for milling a 12" grove and wedge lid for a reactor. Did I happen to miss a cheaper alternative to this in anyones previous writings ? Also, he cautioned me about solely relying on just the wedge and grove because of movement in the metal during heating and cooling cycles. He also said that it should not be made from plate stock as it may have more of a tendency to warp. I believe he suggested something called a slug, which is stock that was formed cylindrically. As I am writing, WTI is approaching $100 per barrel!
                            Last edited by tony steinke; 12-23-2011, 10:09 PM.

                            Comment


                            • Asad, How are you planning to transfer the plastic from one vessel to another? Will it be continuos feed or a batch. I am starting to build my first small reactor but have been following this thread with great interest. Thanks for all the great info

                              Glenn

                              Comment


                              • Please explain the V Grove in Detail

                                Hi All

                                I am currently looking for some material for this project,

                                i am concerned about the V-Grove that Jetjis talks about
                                can somebody explain more about this grove and how to make it.

                                is the v grove just a metal to metal contact with no gasket in between
                                or is there some sort of gasket between the V-Grove

                                please help.

                                Jimmyx

                                Comment

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