I aggree with every thing you said - What we have been able to do , so
far is to extend the portland 20% replacement by weight with
metakaolin high reactivity pozzalon and then extend that mix by 600%
with perlite aggregate- its cheap,dimensionally stable,eco freindly
and fire resistant- and yes sir we still have a long way to go -
apparently magnesium can be extracted from sea water, the problem
seems to be that phosphate is the likely element to combine it with---
In papercreters@yahoogroups.com, "mountainfair" <yahooposting@...> wrote:
>
> I believe that the difference is that the CO2 that we exhale was taken
> out of the atmosphere recently, and does not affect the carbon
> balance, while the CO2 from fossil fuels has been in the ground for
> millions of years and does affect the atmospheric balance of carbon
> when released.
>
> Also, just as the straw bales and other materials may have been
> trucked in from out of state, the portland cement you are using was
> probably trucked in from fairly far away as well.
>
> There are some other factors stacked against portland cement - there
> are currently large debates here in CO over concrete plants that are
> burning tires in their kilns and releasing dioxins and other nasty
> stuff that neighboring communities are not happy about.
>
> In some areas of the world the limestone used for making cement is
> stripmined, displacing native people and destroying large amounts of
> wildlife habitat. The same could be said for a lot of the coal that
> is used as well, as well as drying up aquifers to transport the coal
> in slurry form.
>
> With adobe and rammed earth, you would also have to ask what is the
> footprint of running fossil fuel machinery to excavate, sift and mix
> the dirt and hydraulically compress the earth. Unless, of course,
> they are running the machinery on biodiesel.
>
> Apparently there are emerging alternatives:
>
> Carbon neutral concrete:
>
> http://www.ecocem.ie/
>
> and
>
> • ecocement – magnesium based replacement for ordinary (portland)
> cement which soaks up (sequesters) carbon dioxide as it cures. A sharp
> contrast to portland cement. Experts predict it will take 10 years for
> this to be a feature in the market place. We aim to help this
> innovation get over the market inertia and shrink this time frame.
>
>
>
>
> --- In papercreters@yahoogroups.com, "clydetcurry" <clyde@> wrote:
> >
> > in other words- if we sit around debating for a year over the fact we
> > will exhale more CO2 than building our house would have produced-
> > amazing- boy am I glad you folks have gotten around to this - Clyde T.
> > Curry--- In papercreters@yahoogroups.com, Greg House <ghunicycle@>
> > wrote:
> > >
> > > My father worked in the cement and lime production industries most
> > of his life. From what I've seen from his work, most cement kilns are
> > fired with coal.
> > >
> > > Greg
> > >
> > > ----- Original Message ----
> > > From: Mikey Sklar <sklarm-yahoo@>
> > > To: "papercreters@yahoogroups.com" <papercreters@yahoogroups.com>
> > > Sent: Wednesday, August 8, 2007 10:32:47 AM
> > > Subject: Re: [papercreters] Re: 26lbs of CO2 per bag of Portland
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > When Portland cement is being made from limestone,
> > natural gas or
> > >
> > > propane is used to heat the limestone. White portland would have a
> > >
> > > even higher CO2 footprint as it is cooked longer.
> > >
> > >
> > >
> > > On Aug 8, 2007, at 9:21 AM, "slurryguy" <slurryguy@yahoo. com>
wrote:
> > >
> > >
> > >
> > > > Does clinker outgas CO2 as it is getting fired? How much?
> > >
> > > >
> > >
> > > > I'm not disagreeing with your overall point. I actually agree.
> > >
> > > >
> > >
> > > > --- In papercreters@ yahoogroups. com, Mikey Sklar
> <sklarm-yahoo@ ...>
> > >
> > > > wrote:
> > >
> > > >>
> > >
> > > >>
> > >
> > > >> I have been tormented by a few local adobe and straw bale
builders
> > >
> > > >> for my use of Portland cement. They point out to me that by using
> > >
> > > >> a high energy product that I am destructive to the environment. I
> > >
> > > >> had my doubts and decided to run some numbers this evening about
> > >
> > > >> just how much CO2 was being produced to create a bag of portland.
> > >
> > > >> The answer I came to was less than 26lbs of CO2 per 94lb bag of
> > >
> > > >> portland. I suppose I can now point out to the so called green
> > >
> > > >> builders who are hauling straw bales or pre made adobes from
across
> > >
> > > >> state boarders that their CO2 footprint is orders of magnitude
> > >
> > > > larger
> > >
> > > >> than my own.
> > >
> > > >>
> > >
> > > >> - portland cement 4,700,000 million btu per ton
> > >
> > > >>
> > >
> > > >> - convert btu's per ton to one bag of Portland (94lbs)
> > >
> > > >> * 1 ton 2000lbs
> > >
> > > >> * 2000 / 94 = 21.28
> > >
> > > >> * 4700000 / 21.28
> > >
> > > >> * 22,0864.66 btu's per bag
> > >
> > > >>
> > >
> > > >> - convert btu's of natural gas to pounds of CO2
> > >
> > > >> * 1 million BTUs (NG) will produce 117.08 pounds of CO2
> > >
> > > >>
> > >
> > > >> - convert btu's per ton of portland to pounds of CO2
> > >
> > > >> * 4,700,000 / 1,000,000 = 4.7
> > >
> > > >> * 4.7 * 117.08
> > >
> > > >> * 550.276 lbs of CO2 per ton of Portland made from Natural Gas
> > >
> > > >>
> > >
> > > >> - convert lbs of CO2 per ton of Portland to bag of Portland
> > >
> > > >> * 550.276 / 21.28
> > >
> > > >> * 25.86 lbs of CO2 per bag of Portland
> > >
> > > >>
> > >
> > > >> When we consider that jet fuel, diesel, and car fuel all produce
> > >
> > > >> about 20 lbs of CO2 per gallon we can see that a bag of Portland
> > >
> > > >> is producing the same amount of CO2 as driving 20 miles in your
> > >
> > > >> truck.
> > >
> > > >>
> > >
> > > >> If you want to bring yourself to neutral on CO2 for your Portland
> > >
> > > >> usage. Consider that the average tree will absorb 26lbs of
CO2 per
> > >
> > > >> year.
> > >
> > > >>
> > >
> > > >> Keep in mind that we humans on average exhale over 2lbs of
CO2 per
> > >
> > > >> day.
> > >
> > > >>
> > >
> > > >
> > >
> > > >
> > >
> > > >
> > >
> > > >
> > >
> > > >
> > >
> > > > Yahoo! Groups Links
> > >
> > > >
> > >
> > > >
> > >
> > > >
> > >
> > > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > <!--
> > >
> > > #ygrp-mlmsg {font-size:13px;font-family:arial, helvetica, clean,
> > sans-serif;}
> > > #ygrp-mlmsg table {font-size:inherit;font:100%;}
> > > #ygrp-mlmsg select, input, textarea {font:99% arial, helvetica,
> > clean, sans-serif;}
> > > #ygrp-mlmsg pre, code {font:115% monospace;}
> > > #ygrp-mlmsg * {line-height:1.22em;}
> > > #ygrp-text{
> > > font-family:Georgia;
> > > }
> > > #ygrp-text p{
> > > margin:0 0 1em 0;}
> > > #ygrp-tpmsgs{
> > > font-family:Arial;
> > > clear:both;}
> > > #ygrp-vitnav{
> > > padding-top:10px;font-family:Verdana;font-size:77%;margin:0;}
> > > #ygrp-vitnav a{
> > > padding:0 1px;}
> > > #ygrp-actbar{
> > > clear:both;margin:25px
> > 0;white-space:nowrap;color:#666;text-align:right;}
> > > #ygrp-actbar .left{
> > > float:left;white-space:nowrap;}
> > > .bld{font-weight:bold;}
> > > #ygrp-grft{
> > > font-family:Verdana;font-size:77%;padding:15px 0;}
> > > #ygrp-ft{
> > > font-family:verdana;font-size:77%;border-top:1px solid #666;
> > > padding:5px 0;
> > > }
> > > #ygrp-mlmsg #logo{
> > > padding-bottom:10px;}
> > >
> > > #ygrp-vital{
> > > background-color:#e0ecee;margin-bottom:20px;padding:2px 0 8px 8px;}
> > > #ygrp-vital #vithd{
> > >
> >
>
font-size:77%;font-family:Verdana;font-weight:bold;color:#333;text-transform:uppercase;}
> > > #ygrp-vital ul{
> > > padding:0;margin:2px 0;}
> > > #ygrp-vital ul li{
> > > list-style-type:none;clear:both;border:1px solid #e0ecee;
> > > }
> > > #ygrp-vital ul li .ct{
> > >
> >
>
font-weight:bold;color:#ff7900;float:right;width:2em;text-align:right;padding-right:.5em;}
> > > #ygrp-vital ul li .cat{
> > > font-weight:bold;}
> > > #ygrp-vital a {
> > > text-decoration:none;}
> > >
> > > #ygrp-vital a:hover{
> > > text-decoration:underline;}
> > >
> > > #ygrp-sponsor #hd{
> > > color:#999;font-size:77%;}
> > > #ygrp-sponsor #ov{
> > > padding:6px 13px;background-color:#e0ecee;margin-bottom:20px;}
> > > #ygrp-sponsor #ov ul{
> > > padding:0 0 0 8px;margin:0;}
> > > #ygrp-sponsor #ov li{
> > > list-style-type:square;padding:6px 0;font-size:77%;}
> > > #ygrp-sponsor #ov li a{
> > > text-decoration:none;font-size:130%;}
> > > #ygrp-sponsor #nc {
> > > background-color:#eee;margin-bottom:20px;padding:0 8px;}
> > > #ygrp-sponsor .ad{
> > > padding:8px 0;}
> > > #ygrp-sponsor .ad #hd1{
> > >
> >
>
font-family:Arial;font-weight:bold;color:#628c2a;font-size:100%;line-height:122%;}
> > > #ygrp-sponsor .ad a{
> > > text-decoration:none;}
> > > #ygrp-sponsor .ad a:hover{
> > > text-decoration:underline;}
> > > #ygrp-sponsor .ad p{
> > > margin:0;}
> > > o {font-size:0;}
> > > .MsoNormal {
> > > margin:0 0 0 0;}
> > > #ygrp-text tt{
> > > font-size:120%;}
> > > blockquote{margin:0 0 0 4px;}
> > > .replbq {margin:4;}
> > > -->
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> >
>
____________________________________________________________________________________
> > > Take the Internet to Go: Yahoo!Go puts the Internet in your pocket:
> > mail, news, photos & more.
> > > http://mobile.yahoo.com/go?refer=1GNXIC
> > >
> >
>
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/papercreters/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/papercreters/join
(Yahoo! ID required)
<*> To change settings via email:
mailto:papercreters-digest@yahoogroups.com
mailto:papercreters-fullfeatured@yahoogroups.com
<*> To unsubscribe from this group, send an email to:
papercreters-unsubscribe@yahoogroups.com
<*> Your use of Yahoo! Groups is subject to:
