Danish chemists report means to clean biomass derived fuels of sulfur

[NNadir]

potassium and chlorine.

The abstract:

"In larger combustion facilities, secondary reactions between char and chlorine and sulfur may be important. In this work, the interactions of chlorine and sulfur with biomass char during
thermal conversion have been experimentally investigated. A laboratory-scale fixed-bed reactor was applied to study the capture of HCl and SO2 by biomass char in the temperature range of
400-950 °C. The observed reaction rate was sufficient for significant recapture of HCl and SO2 to occur under conditions typical for fixed-bed combustors. A maximum in the chlorine and sulfur retention existed at 600 °C. Relatively high amounts of chlorine and sulfur could be retained in the char samples over the entire temperature range, compared to the inherent chlorine and
sulfur content in the biomass. Spectroscopic and chemical analyses revealed that HCl was mainly captured by the inherent metal species, whereas SO2 was mainly captured by the organic matrix.
As a result, the maximum chlorine retention was dictated by the inherent metal content of the biomass. Combustion of the chlorine- and sulfur-laden char samples resulted in high retention
values of chlorine and sulfur in the ash at temperatures up to 600 and 800 °C, respectively. At higher combustion temperatures, chlorine and sulfur was gradually released to the gas phase,
because of evaporation of KCl and dissociation of sulfates. A larger fixed-bed reactor was appliedto simulate the combustion process that occurs in industrial-scale grate-fired boilers. Combustion of wheat straw samples in the large fixed-bed reactor confirmed that higher retention values of both chlorine and sulfur could be obtained, compared to the smaller laboratory reactor, presumably because of secondary capture."

Biomass is not actually a clean form of energy when compared to say, nuclear or solar energy. However it is infinitely cleaner than oil or coal and has the added advantage of being both renewable and greenhouse gas neutral.

It seems inevitable that we will have to use this form of energy. Therefore it is good to see that scientists (scientists being a breed of human beings that is endangered in the United States but are fairly common elsewhere) are working on ways to minimize the environmental impact of biologically derived fuels.

[papau]

1. interesting- but what is net energy gain of growing, transport and burning

There does not seem to be a great deal out there except small demonstation projects. The link below was interesting - but still no cycle costs/energy numbers (or I am too tired to see them)

:-)

http://www.jfe-holdings.co.jp/en/dme/01-tokucyo.html

[NNadir]

2. In Germany, biological fuels constitute about 10% of the diesel output.

Ten percent of a major fuel in a major industrial nation is an industrial process as opposed to a demonstration project.

http://www.cleanairnet.org/infopool/1411/propertyvalue-19517.html

I don't think this is particularly clean energy when viewed in opposition to other alternatives. In fact I know it's not.

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=5609&mesg_id=5609

Still it is much, much, much, much cleaner and safer than oil and coal and thus is worthy of encouragement.

[papau]

3. But we have large production of corn alcohol to mix with gas and that is

an energy sink - we use more energy to grow/transport/process/distribute the alcohol energy than we get out of it in driving.

For years folks pointed out the Nuke power plant economics were crazy - even if you ignored spent fuel storage/reprocess and plant closing costs, you still never earned a dime relative to other fuel.

So what I am curious about is the complete cycle cost/benefit compared to other options.

[NNadir]

4. For years people were completely wrong about nuke economics.

Nuclear power is one of the cheapest forms of energy available anywhere, just about in every type of cost too, environmental, economic, and sustainability costs. Indeed, if even only the "fuel and plant only" costs are included, nuclear is usually as cheap as coal. (Coal is cheaper on this partially loaded basis only when coal mines are in close proximity, but where coal must be transported, nuclear energy is clearly cheaper.)

The direct cost of producing electricity from either coal or nuclear is about 2 cents/kw-hr. http://www.uic.com.au/nip08.htm The chief drawback to nuclear energy has nothing to do with either technical or economic issues; mostly it is about mysticism.

Like all forms of energy, biomass is very much dependent on locality. If one transports it very far, it is really not economic. If one needs intensive irrigation or intensive fertilization to sustain it, or intensive energy to harvest it, it is also less economic. If on the other hand, one is using biomass in an agricultural area with sufficient rainfall and if one has undepleted soils, I'm sure biomass can be quite competitive, especially with oil in the $40-50/barrel range.

Comparisons between nuclear and biomass are difficult because biomass is generally used for space heating and for motor fuels, whereas the vast majority of nuclear energy today is used for the production of electricity. Still I'm quite sure that high temperature reactors like those under design in China, India, and South Africa would probably be able to drive biomass fuels out of business rather quickly, once developed and installed.

However we all need to recognize that, irrespective of these alternative particulars, petroleum is a highly subsidized fuel. Its costs are simply dumped on the public at large sometimes in the form of pollution and sometimes in the form of bombs.

I am very appreciative of the work of the international chemistry community on behalf of biologically derived fuels. This is why I often report them here. I regret that there are so few Americans exploring these issues. I think for the most part they're important and they're very real and very viable schemes.

[papau]

5. Nuke health , environment and Decommissioning costs are said to be

much higher than that shown in the EU study.

Indeed a cash flow model done in the US about 10 years ago showed that you never got a positive return on the upfront capital invested in a new plant. And that is why US electrics stop building nukes.

We need a cash flow model for each energy source, as well as a net energy gained model.

[NNadir]

6. Said by whom?

The EU research involved the work of thousands of scientists and engineers and the reports for each country contain hundreds of references each.

Therefore a reference to the claim "are said to be" would seem to be required.

It is difficult to imagine, BTW, a form of energy that gives as much net gain in energy as nuclear does. 1 ton of Uranium is equivalent to 3 million tons of coal and 12 million tons of oil.

This would give one pause to consider the seriousness of any statement about net gain in energy. Nuclear energy is the primary source of all energy in the universe.

[papau]

8. No - not net gain in energy with nuke - it is economics - its a sink hole

My goodness I gave no link because I thought it was well known - Heck PBS and the BBC both did specials on the economics 20 years ago.

Until nuke has a disposal method and a decomission total cost for real, the numbers are wild eye guesses. But the low ball numbers of the 70's have already been proven wrong.

The neat thing is that new designs - like the no melt down pebble bed design - may have very different economics.

But the water cooled Westinghouse standard model is not cost effective - which is why it can't be sold these days.

The EU paper indeed had good research - but no total life cycle costs since everything is on hold as we try to find a disposal method. Meanwhile containment shields are getting weak - the radiation kills those shields in a few decades - and the problem is not going away.

Alcohol was a shock to me when I saw that it was a net energy loss - and little oil use was cut - via adding it to our driving. Polution savings perhaps and it helped corn growers. But not an energy solution.

There is a lot of PHD work to be done! Heck my friend who almost married into the family got his PHD in "simple" better control programs for the reaction. I know only what I read and am told about energy. But so far I do not see the solution - or I do not understand the solution (at my age that latter is a real possibility!) :-)

peace

:-)

[NNadir]

9. No it is not "well known." It is, in fact, an urban myth.

Again, the EU report is filled with pages and pages of references.

People who embrace this "conventional wisdom" about nuclear energy are almost NEVER scientists.

Nuclear power is the second cheapest form of energy known on a partially loaded (direct cost) basis, beat only in some localities by coal.

On a fully loaded basis (including external costs) it is THE cheapest form of energy known.

I find it useful to look at data that is less than 20 years old.

Who has looked into the decommissioning costs of strip mines by the way?

[papau]

10. True - as to strip mines-so Nuke non-building has been all political -and

not economic?

Thanks for hanging in there with me. I really did not see the reference that gave the fully loaded cost numbers comparison.

If there is a link for my libary of neat links, I'd appreciate it - but don't go too far out of your way to run such down if you dob't have it at your fingertips, as I am happy to accept that I was going with old data and that current data makes nukes "work".

Indeed that is good news!

peace

:-)

[NNadir]

11. Yes, this is true.

I have lots and lots (probably thousands) of references on the subject on nuclear power on my other computer at home and I am continually referencing them here.

The Swiss Paul Scherrer (sp?) Institute (Paul Scherrer played an important role in WWII espionage because of his close friendship with Bohr and Heisenberg and many other important physicists) did an interesting study of fully loaded (direct and external) costs of all forms of energy. In this study, nuclear energy and wind energy were unquestionably the best by a huge margin. I will attempt to post a link to that study if I can find it.

As for the economics of nuclear power, I note that there are over 400 operating nuclear reactors running worldwide. More than 75 new ones are either under construction or in late stage planning and 100's more have been proposed.

The fact that there are not as many being built as need to be built to save the planet is a direct function of the power of ignorance and myth. That seems mysterious in our allegedly "modern" time, but I can offer no other explanation.

[papau]

12. Thanks for correcting me - my friend went to work in the EU as they are

still building new nukes - as you noted.

The 75 number is a factor of 10 larger than I would have guessed!

Man, the older I grow, the more I can not even guess at , much less "know".

:-)

[Viking12]

7. Can you direct us to information on Nuke Economics

That isn't provided by the Nuke Industry???

The UIC appears to be a mining industry association/front group.

[NNadir]

14. You can start with the references at the bottom of the link.

In spite of the rather loaded claim of the UIC being a "front group" the fact is that many of the people referenced in that same link are not connected with either the mining or the nuclear industries. OECD is not a mining interest for instance.

This may come as a surprise, but people who work in the nuclear industry often don't do so because they are intrinsically evil greedy liars. It is not easy to become a nuclear engineer. It requires exhausting effort in fact, but once one has made the effort, and one understands this very high technology, one is impressed with how well it actually works.

Now, I personally have no formal training in nuclear engineering, although I've more or less spent twenty years in an learning about it autodidactically. I do not work in the industry because I am not certifiably qualified to do so. I am an old man now, but if I were a young man, I would certainly choose a career in nuclear engineering and I would certainly seek a job in that industry. Why? Because it is the right thing to do. Nuclear engineering is a noble profession consistent with some of the highest values of liberalism. I make this statement because the operations of nuclear power demand an infrastructure in which people can become highly educated, work at high paying extremely productive low risk jobs, maximize the opportunity for the elimination of poverty, promote the furtherance of peace while at the same time minimizing the environmental impact of their prosperity. Indeed, I am fortunate to have two young sons in my waning years, and I am giving them as much exposure to math and physics at a young age as they can comfortably stand in hopes that they will be inspired to exactly this career.

Let's do this differently. Why don't I challenge you to produce authorative evidence that nuclear power is MORE expensive than any other form of energy, i.e why don't you produce evidence that the references cited in the UIC link are lying? (The website of idiotic ignornant comedy troupe Greenpeace does not constitute such a reference, nor does www.ratical.org.) Such a reference would need to explain how it is that the 400+ nuclear power plants now operating have not been shut down for economic reasons, why so many more are being built, and such a reference would also have to demonstrate that the persons writing it actually know something about energy. (This would exclude, for instance, Ralph Nader.)

Another poster on this site has just produced another thread here about the groundswell of environmentalist support for nuclear energy that has nothing to do with the industry. The issue of costs is, I believe, addressed therein.

The most prominent non-nuclear industry advocates for nuclear energy include the widely cited Health Physicist Bernard L. Cohen whose book, "The Nuclear Energy Option" includes a few thousand references on both the safety and cost of of nuclear energy, the Pulitzer Prize winning author Richard Rhodes ("Nuclear Renewal") and apparently James Lovelock (with whom I am largely unfamiliar). There are many other nuclear power advocates from outside the industry who are far less famous and far less important, including one NNadir. Some of these advocates are friends of mine. I convinced them myself.

[AZCat]

15. The sad thing is that Nuclear Engineering programs are dying

Both universities I have attended have shut down their Nuclear Engineering programs, one while I was there.

In fact, the University of Arizona (where I currently am) is shutting down its reactor over the next ten years or so.

If we do ever manage to get the capital amassed to build the next generation of reactors we will be scrambling for qualified personnel.

:(

[NNadir]

16. Science has no place in the American future.

This is not simply true of nuclear engineering, but it is also true of the other sciences, I think.

I remember a very, very, very sarcastic lecture on this subject by the Nobel Laureate D.H.R Barton who used closed with a list of his group members and their countries of national origin. I'll paraphrase his remarks about his lone American post doc: "This is my lone American. Every lab should have one. They're getting harder and harder to find, of course, because all Americans just want to go to business school."

I suspect that things are about to get much, much, much, much worse under the dictatorship of the MBA's.

[amandabeech]

13. It has been proposed that other, less nutrient demanding plants,

be considered for alcohol production now that scientists have developed a better method of making alcohol from cellulistic (sp)plant matter.

Switch grass has been proposed as have some woody waste products from paper mills and paper at the end of its recycling life.

We must be careful, though, to avoid claiming all biomass "waste" for ethanol production. Much of the "waste" composted can serve as a combination fertilizer and soil enhancer. Nitrogen fertilizer is made with considerable amounts of natural gas, and phosphorous and potassium are mined, processed and shipped great distances to farm fields. Although potassium is though to be sufficiently plentiful, in the United States we are expected to run out of decent-quality phosphorous in 75-100 years. Plants require phosphorous, and recycling would help us sustain reasonably high yields of agricultural production much farther into the future.

I agree with you whole-heartedly about corn, and I am not deluded that ethanol will make a huge contribution to our liquid fuel requirement in the future.