Announcement

Collapse
No announcement yet.

Adsorbed Natural Gas Technology

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    Re: Absorbed Natural Gas Technology

    Check the gas-tec site, their largest tank only holds 130 cf at 275psi, barelly 1 therm. Seems hardly worth it for all the hype.

    Comment


    • #17
      Re: Absorbed Natural Gas Technology

      Sounds a lot like what they're doing with Hydrogen. Trying different media like nickel medal hydride to get more H2 molecules to bond with media than in free space under less pressure.
      Talk about a cost savings, just imagine the tank price compared to a Lincoln Composites 10,000psi Type 4 Hydrogen cylinder.
      Your Friendly Nazi Squirrel Administrator

      Comment


      • #18
        Re: Absorbed Natural Gas Technology

        OK;

        This is where my engineering degree comes in handy. The technology is called 'adsorbed' instead of 'absorbed' because the gas is not inside the carbon microstructure. It's just resting on the surface of all the tiny little pores. In the case of a corncob, the material is already quite porous to begin with (hence its traditional use in outhouses), so all you have to do to make it physically (not chemically) store even more gas is to lower the surface energy of the cob w/ respect to the NG.

        By reducing the cob to charcoal--which is not the same as burning it, because burning oxidizes the material (speed rusting)--the original tiny pores are kept and even more tiny pores are generated as the volatiles (not sure of the accuracy of that term) are removed. You have not really "burned" the material upon making charcoal, you have just reduced (solid version of distilling) the amount of matter for burning at a later time--hence charcoal being used for steaks, etc.

        I will also guess that the high-carbon surface and the methane have a low dispersive interaction--the NG molecules are mildly attracted to the carbonized surface rather than repelled. If you took any advanced chemistry, that's covered under London dispersive forces (Van der Waals). If you didn't, it's why oil and water don't mix, but you can steal a little bit of hospital alcohol for your weekend bender by pulling a gallon off the top and replacing it with water--not that Ive ever done so...

        End of lecture: write your own @#$ pop quiz and keep your own grade book.
        Last edited by Andy-Paul; 06-09-2008, 11:22 AM. Reason: clarity

        Comment


        • #19
          Re: Absorbed Natural Gas Technology

          As for whether or not the storage medium wears out....

          I *think* that it might lose some surface area due to cyclical stress on the outer edges of the briquette.

          The reduced attached surface area (as opposed to the rubble from the breakage) would require higher pressure to store the same amount of NG. The question then becomes, what will the rubble do, and how would it behave? If the pressurized NG just expands it (like water in bentonite) the cyclical stress may actually prove beneficial to storage capacity. If the particles are sufficiently large compared to the pores next to their break-off space, they could actually provide more storage space via their extra surface area. If they tend toward a regular shape and are smaller than the pores, they would have the opposite effect.

          Finally, how the rubble moves about in the fuel tank could make for some very interesting fuel filtering issues. Maybe just a micron filter? I think any diesel mechanics among us could answer that one.

          Comment


          • #20
            Re: Absorbed Natural Gas Technology

            check my math

            Does 180 times the volume to charcoal mean you could get 180 gals of gas in a one gallon container of charcoal.

            http://www.greencarcongress.com/2007...ghdensity.html

            1 GGE is = to 124 cubic feet of Natural gas.

            1 US gallon = 0.133680556 cubic feet
            1 us gallon with charcoal(corn)0.133680556 x 180 = 24.06 cubic feet so a
            you would need about 5.15 gallon tank to hold 1 GGE.

            Comment


            • #21
              Re: Absorbed Natural Gas Technology

              From what I've seen, current technologies allow for about a 20% increase in storage over conventional tanks.

              Comment


              • #22
                Re: Absorbed Natural Gas Technology

                Originally posted by Uraijit View Post
                The cool part though, is the lower pressure, which allows the tank to be made in virtually ANY shape and size! Imagine being able to build a CNG tank (rather than Cylinder) that is the same size and shape as your gasoline tank, or your spare tire well, or that fits under the back seat of your SUV. Or one that fits between the frame, and the bed of the truck. Or that lays down flat in your trunk/cargo area, and only sits 2-3" high! Or all of the above!

                These tanks are quire possibly the technology that will push us over the "inconvenience hump" that's kept it from taking off. Not to mention that the cost of production would be much less than a 3600 PSI cylinder. Price and convenience of tanks are the two biggest hurdles for this industry, as I see it.

                If we can overcome those two hangups, the fueling infrastructure problem will be rather quick to fix itself.
                Especially if you could make a tank out of carbon fiber, because you could custom fit it to your vehicle. You would take a lot of weight off of the car and probably increase fuel mileage.

                Comment


                • #23
                  Re: Absorbed Natural Gas Technology

                  Originally posted by Uraijit View Post
                  Er, those tanks are small welding size tanks. Seems you hardly know what you're talking about
                  Thank you for the personal attack. I agree, but still not much gas increase for all the hype. You either get lower presure or more capacity. Most are talking about tanks of 500 psi. This would contain far less has than a conventional tank at 3600 psi, so not really a functional improvement, except of course for allowing more choice in tank location.
                  Last edited by CanAm; 06-10-2008, 02:25 PM.

                  Comment


                  • #24
                    Re: Absorbed Natural Gas Technology

                    Idarussky;

                    I think you may be using the wrong units to compare things. One gallon of charcoal is not one gallon because it is not a liquid or a gas, which will fill a flask to an homogeneous distribution of atoms/molecules. It is a volume that surrounds a system that has some charcoal in it and either some kind of gas or un-occupied space in the places where the charcoal is not. Therefore, you can't directly compare the charcoal system with an unencumbered gallon of NG. You have to compare the surface area of the charcoal to the surface area of the NG and the excluded (not charcoal) volume in the system.

                    The most important thing to remember is that the more convoluted the surface area of the briquet, the more parking spaces there are for the NG molecules--which, incidently, don't behave very much like an ideal gas due to their tetrahedral shape. Ideal gases are considered to be mono-atomic and made of spherical atoms/molecules.

                    If I can work it out on paper for you, I will post it. It may involve more mathematics than I can remember at this point, but then again it might not. This stuff involves places I haven't been in a good long while....
                    Last edited by Andy-Paul; 06-10-2008, 08:39 PM. Reason: additional point

                    Comment


                    • #25
                      Re: Absorbed Natural Gas Technology

                      Originally posted by Uraijit View Post
                      I guess I'm not understanding what it is that you wanted these tanks to do then...
                      CanAm and Uraijit;

                      The reason that so much less pressure is required is because the charcoal's surface allows the NG molecules to get closer together without bouncing off of each other and getting into the whole dispersive force game. The charcoal absorbs the dispersive energy of the NG by giving each methane molecule a place to park. That lowered energy is passed on to other molecules in the charcoal free parts of the system, which then bounce around less so that you can get more of them together without having to press as hard on them.

                      Comment


                      • #26
                        Re: Absorbed Natural Gas Technology

                        I fully understand how ANG works, have from the beginning. I was hoping that the increase in storage would be greater. That is all I am saying.

                        Comment


                        • #27
                          Re: Absorbed Natural Gas Technology

                          Originally posted by Andy-Paul View Post
                          Idarussky;

                          I think you may be using the wrong units to compare things. One gallon of charcoal is not one gallon because it is not a liquid or a gas, which will fill a flask to an homogeneous distribution of atoms/molecules. It is a volume that surrounds a system that has some charcoal in it and either some kind of gas or un-occupied space in the places where the charcoal is not. Therefore, you can't directly compare the charcoal system with an unencumbered gallon of NG. You have to compare the surface area of the charcoal to the surface area of the NG and the excluded (not charcoal) volume in the system.

                          The most important thing to remember is that the more convoluted the surface area of the briquet, the more parking spaces there are for the NG molecules--which, incidently, don't behave very much like an ideal gas due to their tetrahedral shape. Ideal gases are considered to be mono-atomic and made of spherical atoms/molecules.

                          If I can work it out on paper for you, I will post it. It may involve more mathematics than I can remember at this point, but then again it might not. This stuff involves places I haven't been in a good long while....


                          Thankyou for your efforts.

                          Comment


                          • #28
                            Re: Absorbed Natural Gas Technology

                            http://www.ornl.gov/~webworks/cppr/y...isc/114925.pdf

                            This is a nice little description of what is going on in a charcoal/methane system, as well as touching on the difficulties around pore size. I am still working on the math.

                            Comment


                            • #29
                              Re: Adsorbed Natural Gas Technology

                              I believe Camryman sent this to me a while back and I just ran across it. I thought I'd pass it along for those who get all weak in the knees over this kind of stuff. Enjoy, perhaps it will make things a little clearer for some, and confuse the hell out of the rest of you. By the way, good job Camaryman!

                              Attached Files

                              Comment


                              • #30
                                Re: Adsorbed Natural Gas Technology

                                I've sent a copy of this thread to Sen. Pelosi for review.

                                Comment

                                Working...
                                X