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Can biofuel replace petro oil, or can petro oil be farm produce?

by dan020350
Tags: biofuel, farm, petro, produce, replace
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dan020350
#1
May8-14, 08:17 AM
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Is bio-fuel the answer for man's problems, or can we produce petro rather fighting over it?
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Drakkith
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May8-14, 11:27 AM
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Neither. Biofuel cannot be produced in large enough amounts to sustain the world and we cannot produce regular petroleum oil from anything at this time.
DrStupid
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May8-14, 11:45 AM
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Quote Quote by Drakkith View Post
cannot produce regular petroleum oil from anything at this time.
We can (e.g. by hydrothermal liquefaction) but as you already mentioned not with the required quantities.

DrDu
#4
May8-14, 02:07 PM
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Can biofuel replace petro oil, or can petro oil be farm produce?

I read yesterday a statement of Michel (who got the Nobel prize for his work on photosynthesis) that the overall efficiency of plants to produce fuel is very low (only about 1 % or so) especially when compared to photovoltaic installations.
dan020350
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May8-14, 02:36 PM
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Quote Quote by DrStupid View Post
We can (e.g. by hydrothermal liquefaction) but as you already mentioned not with the required quantities.

We can? Such as hydrothermal liquefaction? And what other ways also?
AlephZero
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May8-14, 03:09 PM
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Quote Quote by dan020350 View Post
And what other ways also?
All the petroleum underground (and all the coal) was produced from plants. The only problem is, that process takes rather a long time.
dan020350
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May8-14, 03:29 PM
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Quote Quote by AlephZero View Post
All the petroleum underground (and all the coal) was produced from plants. The only problem is, that process takes rather a long time.
Anyway way we can haste that process?
DrDu
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May9-14, 01:08 AM
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Quote Quote by dan020350 View Post
We can? Such as hydrothermal liquefaction? And what other ways also?
E.g. Fischer Tropsch reaction.
Einstein Mcfly
#9
May26-14, 12:23 AM
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This is a much more complicated issue than is being expressed here. Firstly, there are a number of ways that biomass derived chemicals can be "upgraded" into gasoline, jet fuel or diesel fuel. There are also calculations that, depending on the bio-fuel that you're interested in, the feedstock agriculture that you're willing to devote and the technique/techniques that you're willing to use (algae, plus bio-diesel, plus alcohols) and how much work you're willing to put into re-configuring the vehicle fleet and infrastructure (see Brazil for what such thing would look like) you could actually go pretty far in replacing fossil petroleum.
Einstein Mcfly
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May26-14, 12:31 AM
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Quote Quote by dan020350 View Post
Anyway way we can haste that process?
Of course. Solid state catalysts, pyrolysis followed by upgrades etc. The process that occurs naturally to make petroleum out of living things is just removing the oxygen so that when everyone's favorite redox reaction occurs (that is, combustion) it's not already partially oxidized (that's why petroleum hydrocarbons are more energy dense than alcohols like ethanol and butanol etc). We have ways of deoxygenating biomass, and a lot of them could be pretty scalable.

The biggest issue is just that plant matter is generally not very energy dense. That is, it takes many acres per unit of fuel. They're working on getting more energy dense crops that don't compete with the food supply (switch grass, miscanthus) rather than corn and such. One way that people are thinking they could get around this (if what you want is ethanol) is the algae route. There's a lot of water on earth that can support algae and you can get them a lot denser than you can get plants on land. That may be the wave of the future to produce the sugar inputs for ethanol formation.
SteamKing
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May26-14, 01:36 AM
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Quote Quote by Drakkith View Post
Neither. Biofuel cannot be produced in large enough amounts to sustain the world and we cannot produce regular petroleum oil from anything at this time.
Quote Quote by DrStupid View Post
We can (e.g. by hydrothermal liquefaction) but as you already mentioned not with the required quantities.
Quote Quote by dan020350 View Post
We can? Such as hydrothermal liquefaction? And what other ways also?
The Germans had been looking to use their relatively plentiful supplies of coal to produce synthetic substitutes for petroleum, which was in short supply in the country. Their efforts began before WWI and continued in the interwar years as the global economy began the great shift from coal to oil for fuel, chemical feedstocks, etc.

http://en.wikipedia.org/wiki/Synthetic_fuel

The Bergius process was developed before WWI with the goal of converting coal to liquid hydrocarbon fuels.

http://en.wikipedia.org/wiki/Bergius_process

After the war, the Fischer-Tropsch process was developed in 1925 to allow the production of liquid hydrocarbons from hydrogen and carbon monoxide gas, which would also use coal as a raw material.

http://en.wikipedia.org/wiki/Fischer...ropsch_process

When Hitler assumed power, he realized that his vision for mechanized armed forces (the Panzertruppe, the Luftwaffe, and to a lesser extent, the Kriegsmarine) could not be realized if he did not have access to vast quantities of petroleum or some substitute from which liquid fuels could be made. As Germany had no petroleum reserves to speak of, but large quantities of coal, a synthetic petroleum program was devised to manufacture fuel for the new Wehrmacht.

Several different plants were established all over Germany to produce fuels and lubricants for industrial and military purposes. After war broke out in 1939, the Allies soon realized that if the synthetic oil plants could be destroyed by aerial bombing, Hitler's forces could soon be brought to a screeching halt for lack of fuel.

http://en.wikipedia.org/wiki/Oil_Cam...f_World_War_II

Hitler tried to offset this vulnerability by seizing oilfields in Romania, and he was driving toward Russian oilfields in the Caucasus and on the Caspian Sea during his summer offensives in 1942 when he was checked by the quagmire called Stalingrad.

The aerial bombardment of the synthetic oil plants in Germany consumed a lot of men and planes, and the results were mixed. The German war machine was beginning to be starved of fuel in 1945, but the real reduction in supplies didn't take place until plants inside Germany were captured by Allied forces. German tanks and planes often could not operate because fuel was in short supply, and key objectives of Hitler's last western offensive (the Battle of the Bulge) were to capture Allied fuel dumps to permit German forces to drive toward Brussels and to capture the large port at Antwerp.

After this campaign failed, fuel became critically short in Germany, which was felt in shortened training time for pilots for the Luftwaffe as well as grounding of fighter aircraft for lack of fuel.

After the war ended, the German synfuel plants were carefully examined by the Allies, and several pilot plants were built in the US using information gleaned from the German program. But, gasoline made from natural petroleum was so plentiful and cheap that this technology and the pilot plants were never scaled up in capacity, and little further research or work was done in this area until after the first oil embargo in 1973.

The US Synthetic Fuels Corp. was set up by the US Government in 1980 after the second great oil shock caused by the Iranian revolution. This corporation was shut down in 1985 after the price of oil dropped significantly in the early 1980s, but a small coal gasification plant supported by the Dept. of Energy was built in North Dakota and still producing natural gas as late as 2009.

http://en.wikipedia.org/wiki/Synthet...ls_Corporation
Ivan Seeking
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May27-14, 11:33 AM
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http://www.nrel.gov/biomass/pdfs/dismukes.pdf
dan020350
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May27-14, 11:52 AM
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Best answer I have receive so far
mheslep
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May27-14, 08:38 PM
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Quote Quote by DrStupid View Post
We can (e.g. by hydrothermal liquefaction) but as you already mentioned not with the required quantities.
I don't believe physics or existing technology stops the production of the required quantities, that is 18 million barrels per day of liquid hydrocarbon in the US. See, e.g., the Dismukes brief above that indicates the required surface area is manageable. Rather, economics currently prevents this route from occurring: it is far cheaper to pull petroleum out of the ground than to grow precursor above ground and then process it (so far). Also, I suspect the process would require some kind of ocean based biomass, as the water supply must be on the order of some 50 million barrels per day (again US only).
Ygggdrasil
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May27-14, 10:19 PM
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Quote Quote by DrDu View Post
I read yesterday a statement of Michel (who got the Nobel prize for his work on photosynthesis) that the overall efficiency of plants to produce fuel is very low (only about 1 % or so) especially when compared to photovoltaic installations.
Here's a link to an editorial Michel published in Angewandte Chemie two years ago discussing this point. I'm not sure I completely agree with his argument, but it's definitely worth serious consideration.
Ivan Seeking
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May28-14, 01:27 AM
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Quote Quote by Ygggdrasil View Post
Here's a link to an editorial Michel published in Angewandte Chemie two years ago discussing this point. I'm not sure I completely agree with his argument, but it's definitely worth serious consideration.
He uses the worst possible examples of biofuel production. Compare this to information in the link I posted above. The worst case listed for algae is still almost 40 times better than the example of rapeseed cited by the author. He further argues that the energy required for processing typically comes from fossil fuels, which is clearly not a requirement for any biofuel operation having a net positive yield. So biodiesel can be CO2 neutral. A review of the requirements for a fuel farm quickly drive the farm design to the use of biofuels produced on site, for processing and production. Also, as noted by mheslep, algae farms will likely exist in marine environments. In fact, retired ocean oil platforms seem an ideal option as the hubs for large marine algae farms.

When the yields of biofuels per hectare are known, one can easily calculate how much of the energy of the sunlight is stored in the biofuels. For German “biodiesel” which is based on rapeseed, it is less than 0.1 %, for bioethanol less than 0.2 %, and for biogas around 0.3 %. However, these values even do not take into account that more than 50 % of the energy stored in the biofuel had to be invested in order to obtain the biomass (for producing fertilizers and pesticides, for ploughing the fields, for transport) and the chemical conversion into the respective biofuel. This energy normally is derived from fossil fuels. The production and use of biofuels therefore is not CO2-neutral. In particular, the energy input is very large for the production of bioethanol from wheat or maize, and some scientists doubt that there is a net gain of energy. Certainly the reduction of CO2 release is marginal. The yield of second-generation biofuels where entire plants are used may be doubled. However, the energy input probably also increases. For example, in the production of biodiesel by the Fischer–Tropsch process, hydrogen has to be added because syngas obtained from biomass contains insufficient amounts of hydrogen. Taken together, the production of biofuels constitutes an extremely inefficient land use. This statement is true also for the production of bioethanol from sugar cane in Brazil.


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