Loading ...
Sorry, an error occurred while loading the content.
 

RE: [biofuel] RE: [Distillers] Collecting impurities

Expand Messages
  • Tony & Elle Ackland
    Robert, Thanks for the reply. I have a couple of questions/myths that you might help me with... ... How is it that the methanol forms a more positive bond
    Message 1 of 2 , Jun 3, 2000
      Robert,
      Thanks for the reply. I have a couple of questions/myths that you might
      help me with...

      >However, the doubler (or thumper, as
      >some people call it) did most of the work of
      >removing the methanol as it was easily flash
      >cooled by the water in the doubler. Perhaps even
      >more important is the fact that the methanol is
      >easily soluble in the water, and that it is the
      >fact that methanol is a more aggressive solvent
      >(in other words, faster to react with other
      >elements) which makes it react quickly with the
      >water and therefore enter into a chemical mixture
      >or compound.

      How is it that the methanol forms a more positive bond with the water in
      the doubler, compared to the water in the original wash ? I can understand
      it initially being collected in there when the doubler is cold, but doesn't
      this heat up after a while (because of the hot vapours passing through it),
      and then the methanol will start to come out of solution as easily as it
      did off the inital wash ? I haven't seen a doubler in action, but I'd
      figure that it would be operating at around 82-85C after a while - warm
      enough to vaporise a fair bit of its methanol.

      What sort of reaction is taking place - what are the compounds it forms ?
      I had presumed that it would be fairly inert toward water.
      Why wouldn't these form (& stay) in the inital wash too ?

      >Now, the fusil oils get trapped for a
      >different reason. They are also easily removed by
      >the water which is cooling the vapors, but then it
      >gets trapped by the surface tension of the water.
      >It floats to the top, and gets poured off with the
      >bottoms water.

      I wonder if anyone has tried using surface tension modifiers to get this
      happening a little better, non-ionic surfactants and the like ? There must
      be a suitable one out there which would enhance this feature.

      I had presumed that they were retained here (more than in the wash) because
      of the doublers lower temperature than the wash (eg 90-96C), and hence
      lower volitility.

      cheers,

      Tony
    • Robert Warren
      ... From: Tony & Elle Ackland To: Distillers , Biofuel Sent: June
      Message 2 of 2 , Jun 3, 2000
        ------Original Message------
        From: Tony & Elle Ackland
        <Tony.Ackland@...>
        To: "'Distillers'" <Distillers@egroups.com>,
        "'Biofuel'" <biofuel@egroups.com>
        Sent: June 4, 2000 12:20:21 AM GMT
        Subject: RE: [biofuel] RE: [Distillers] Collecting
        impurities

        Robert,
        Thanks for the reply. I have a couple of
        questions/myths that you might help me with...

        >However, the doubler (or thumper, as
        >some people call it) did most of the work of
        >removing the methanol as it was easily flash
        >cooled by the water in the doubler. Perhaps even
        >more important is the fact that the methanol is
        >easily soluble in the water, and that it is the
        >fact that methanol is a more aggressive solvent
        >(in other words, faster to react with other
        >elements) which makes it react quickly with the
        >water and therefore enter into a chemical mixture
        >or compound.

        How is it that the methanol forms a more positive
        bond with the water in the doubler, compared to
        the water in the original wash? I can understand
        it initially being collected in there when the
        doubler is cold, but doesn't this heat up after a
        while (because of the hot vapours passing through
        it), and then the methanol will start to come out
        of solution as easily as it
        did off the inital wash ? I haven't seen a
        doubler in action, but I'd figure that it would be
        operating at around 82-85C after a while - warm
        enough to vaporise a fair bit of its methanol.

        What sort of reaction is taking place - what are
        the compounds it forms ? I had presumed that it
        would be fairly inert toward water. Why wouldn't
        these form (& stay) in the inital wash too ?

        Dear Tony,
        It has to do with the fact that you have a flame
        or an electric heating element under your cooking
        pot. The point of contact with the heat source may
        be well over 120 C or more, depending on what you
        are using for fuel and how closely it is
        controlled. The beer or wash solution is where
        you are applying an excess of heat, really, to
        boil the water which means you need to apply over
        100 C heat, and both the ethanol and methanol are
        boiling long before the water is. Actually, as you
        know from your graphs that you put up on your web
        site, the whole mix is boiling at a lower
        temperature according to the alcohol concentration
        you have. The water in the doubler does indeed
        heat up during the process, but the methanol as a
        vapor is having to pass through a liquid barrier
        (same as the ethanol does) but having more free
        electron holes for the hydrogen atoms of the water
        molecules to adhere to, this happens very quickly.
        If your thumper or doubler is at the bottom of the
        reflux column (rather than isolated as a separate,
        non-attached device like I have seen on some older
        style stills, then in addition to the heat coming
        in from the bottom of the doubler, you also have
        cooling water coming down from above in the relux
        column. This is why your doubler water stays
        liquid: it is getting cooled by water dripping
        from above. Also, this water adds up and has to
        drain out the bubbler overflow drain, because you
        don't want this level to get too high or it will
        begin to trap ethanol, as well.
        This higher the surface area of your packing
        materials inside the reflux column, the better
        this works, as you also have a constant heating
        effect going up and a cooling effect of water
        trickling down. Perhaps only half of the ethanol
        vapors make it up to the top the first time
        through, more likely it is getting condenced
        somewhere midway up the reflux column and falling
        down only to get caught by surface tension on the
        packing material and then re-heated by steam
        rising from below. So there is a surface tension
        phenomon going on withthe packing materials, as
        well.
        If you look at the dynamics of a large commercial
        still, you will find that rather than random
        packing, they have actual flat plates with holes
        in them so there is quite a baffling effect and
        lots of surface area for the up and down reflux
        action to take place. They have calibrated ahead
        of time the exact surce area of all this packing,
        and then know the flow rates ahead of time, as it
        is a standard thermodynamic heat exchanger
        calculation. (I can no longer do the math, but I
        have seen how it is calculated).
        These commercial stills are usually about 10
        meters tall, and they run continuously, instead of
        doing separate batches. The way it works is the
        beer is fed as a liquid by a pump into a port near
        the top of the reflux column, and live steam is
        introducted at the bottom. The steam will also
        have an alcohol content, but you have quite a
        series of waterfalls inside the 25 cm or larger
        column which is the reflux tower. Temperatures
        and flow rates are qute closely controlled, and
        the column is usually insultated so as to
        eliminated any lack of control due to outside
        temperature conditions. So in a large
        commercial still, you have the same process, only
        on a larger scale, and there is very little chance
        that any methanol will get through as it bonds so
        easily to the bottoms water. The other thing to
        remember is the amount o fmethanol is a very small
        percentage, overall compared to your ethanol
        content. Usually in a 5 % beer you will only have
        maybe .1 %, or problaby even lower than that. I
        don't have any of my refernce books on alcohol
        anymore, I sent them all to Keith for use by the
        Biofuel's group, so my figures could be off due to
        the fact that I am just trying to recall stuff I
        read about 25 yrs ago when I was getting started
        in all this.

        >Now, the fusil oils get trapped for a
        >different reason. They are also easily removed by
        >the water which is cooling the vapors, but then
        it
        >gets trapped by the surface tension of the water.
        >It floats to the top, and gets poured off with
        the
        >bottoms water.

        I wonder if anyone has tried using surface tension
        modifiers to get this happening a little better,
        non-ionic surfactants and the like ? There must be
        a suitable one out there which would enhance this
        feature.

        Now, here you are talking about something which is
        going to introduce another chemical or possibly a
        bad taste to the mix.
        Leave well enough alone, and if you do have any
        methanol, it will certainly come out in the
        charcoal filtering and aging processes.
        The charcoal will remove complex organic
        pollutants which you didn't even know you had. The
        limitations of carbon filters is that they con't
        remove non-organic pollutants like lead, mercury,
        cadmium, and other such metalic pollutants.
        However, carbon filters fo a fairly nice job of
        removing chlorine and chlorine compunds, and that
        is great, as some of the chlorine compounds can be
        fairly nasty in small doses.
        This is a separate issue completely, but if you
        ever travel in Mexico or China, it is never safe
        to drink the water, but pretty much always safe to
        drink the beer. The beer factories usually have
        pretty good water filtration, then the alcohol
        kills off the microbes. When I was living in China
        last year, they had one kind of beer that had a
        big ass ugly beetle inside the bottle. A friend
        from the US came to visit me, and when we were in
        the Chinese market, he bought a couple bottles of
        wine to take home (just for display, he didn't
        want to drink it) called "Three snakes wine".
        There were three poisonous snakes curled up inside
        just one wine bottle. Now, I know they put the
        worm in the Tequila bottle in Mexico, but perhaps
        those of you who are looking for an exotic flavor
        ought to consider adding other live critteres to
        your high proof if you are adventurous enough to
        go off exploring new taste terriories.


        I had presumed that they were retained here (more
        than in the wash) because
        of the doublers lower temperature than the wash
        (eg 90-96C), and hence lower volitility.

        Yes, that is also true. It is both the lower temp
        and the reacting with water.
        cheers,
        Robert

        ****************
        * _\|/_
        * {@ @}
        OO-(_)-OOo--
        ****************
        robertwarren@...

        ---------------------
        ______________________________________________
        FREE Personalized Email at Mail.com
        Sign up at http://www.mail.com/?sr=signup
      Your message has been successfully submitted and would be delivered to recipients shortly.