Wednesday, December 01, 2010
Shortage of Rare earth Metals made worse by Smuggling.
REs are not lacking in the earth's crust, and for example cerium ranks as the 25th most abundant element at 68 parts per million, in fact similar to copper. There are however few economically concentrated ores of the metals and their very similar chemical properties make the separation and isolation of individual REs in pure form difficult and expensive.
While China attempts to secure its dominance of the world markets for these metals, the scarcity of REs is compounded by smuggling. As much as 20,000 tonnes or one third of total exports of REs were smuggled out of China, which both reduces the price of the metals and ensures the more voracious depletion of the resource.
In my previous article, I wrote about the British focus on wind-power to meet its renewable energy targets for the European Union, by 2020. I commented that the rate of progress in building the required more than 4,000 new wind turbines had been rather slow to date, and now it appears debatable that there will be sufficient neodymium with which to fabricate the magnets for them, even if the manufacturing could be speeded-up.
China has been making strenuous actions to buy mines of RE ore around the world, to maintain its dominance of the global markets, and I wonder whether this will extend to Greenland, where the melting ice-sheet is likely to ease access to the rich veins of REs and other elements that the world needs to maintain its technologies and energy supplies.
Related Reading.
"Smuggling key factor in rare earths' scarcity," December 2010, Chemistry World, p6.
Sunday, November 07, 2010
British Power is all Wind.
Not everyone is convinced that wind-power is the most reliant route to clean, renewable carbon-free energy, and it is concerning that Britain is relying on a power source that must be backed up by more constant technologies such as nuclear, coal, or gas, because the wind blows inconsistently, as is its nature. A mere 2% of Britain's electricity was produced from renewable sources in 2002, but it is hoped that this should rise to 10% by the end of the year in light of the new wind-power generating capacity.There are further cost issues in upgrading the national grid to cope with power-surges and the need to switch between different power sources.
It should be noted that electricity provides only around one third of the total energy used in the U.K, and the bulk of that is accounted for by heating and transportation, which is supplied by respectively coal/gas and oil based fuels. Hence the UK will have its work cut out if it is to meet a EU target to raise its overall energy provision from renewables from the present 5% to 15% by 2020.
The actualization of an overall wind-power strategy is not going smoothly, however, and the number of new wind-farms coming on-stream has fallen by 30%, in part as a consequence of the recession. There has also been a fall in the past 12 months by 50% in planning approvals for wind-farms in England, a situation that is also reflected in Scotland. There is also considerable opposition to wind-turbines which are perceived as unsightly and noisy, as is reflected by the 230-odd campaign groups that operate across the whole of the U.K.
Indeed, some of these groups advocate nuclear power as a better option than wind, a situation that would have been almost unthinkable ten years ago. It was estimated in 2008 that to meet the U.K. wind-power goal by 2020 would require building one new turbine every day for the next twelve years. Since progress so far has fallen far short of this rate of conversion, little confidence is lent that the nation will be able to keep its promise on renewables.
Wednesday, October 13, 2010
Algae to Fuels Under Pressure.
Removing the water from raw algae is a highly energy intensive process, and to minimise the overall energy costs of biofuel production from algae, a process called hydrothermal liquefaction may instead be employed in which the algae are not dried but heated under pressure such that the water they contain acts as a chemical reagent and solvent that breaks-down the algal cells and converts not only the oil (lipid) but the sugar and protein component into fuels such as liquid hydrocarbons, gaseous fuels like methane and a complex material called "bio-oil" with a similar energy content to crude oil.
Clearly, the design of engines will need to be adapted in order to use these alternative fuels directly, or they must be refined in a "biorefinery" along with those from other kinds of biomass. In both cases of new engines or biorefineries, there will be huge new engineering required and on a scale that can only be guessed at if really algae can be exploited to make a nation the size of the United States independent of cheap imported crude oil.
Nonetheless, there is a consortium (National Algae Association) in the U.S. that is actively seeking a future in which algae are grown on a large scale and converted to oil-alternative fuels. Certainly, it is likely that algae will become an essential component of the mix of means to keep transportation going by means other than crude oil.
The claims of the NAA are undoubtedly true, that ultimately the supply of petroleum must decline, oil prices will continue to be volatile with knife-edge consequences for the world economy, and a wholesale industry based on algae would provide precious and needed jobs and economic development in the U.S. The approach could be introduced on necessary levels for all nations and even a village "pressure cooker" to provide algal fuels for small communities.
Related Reading.
A. Demirbas, "Use of algae as biofuel sources," Energy Conversion and Management, 2010, 51, 2738-2749.
Monday, September 13, 2010
Carbon Capture and Storage (CCS) - Yay or Nay?
Since 100 million tonnes per DAY of CO2 would need to be so sequestered by CCS the engineering required to bring it to fruition is phenomenal. There are essentially two methods to remove carbon from fuel: post-combustion and pre-combustion. Post-combustion, CO2 is removed from flue gas by passing it through a liquid amine which dissolves the CO2. Pre-combustion, the fuel (coal, gas, biomass) is processed into a mixture of CO2 + H2 and the CO2 is removed. Either way, the CO2 must be put somewhere, for which strategies include pumping it into rocky formations (such as depleted oil and gas wells) at a pressure of 100 atmospheres, or even piping it in liquid form under pressure onto the sea-floor where it is cold enough and the pressure high enough that it is hoped the material will stay there, assisted by the formation of CO2-hydrate.
(1) C Tsouris, D S Aaron and K A Williams, 2010, Environ. Sci. Technol., 44, 4042
(2) http://www.rsc.org/chemistryworld/Issues/2010/September/DoWeReallyNeedCarbonCaptureStorage.asp
Tuesday, September 07, 2010
So, What Did Happen After the Chinese Oil-Spill?
Around 1,500 tonnes of crude-oil ended-up in the Dalian Bay, which is a popular resort for tourism and conferences, located in the far east of China. The initial clean-up was pretty much over in two weeks, but residual problems in safety management are highlighted. As usual, there are various estimates of the size of the resulting oil-slick, of between 150 - 450 square kilometers of ocean covered, but the main concern is that the oil might contain toxic organic contaminants that could invade the food-chain, threatening the health of humans, animals and that of the wider environment for decades to come.
It is argued that a lack of technical expertise and equipment in China made the clean-up process more complicated and protracted than it need have been. Many thousands of workers were garnered in Dalian and simply sent-out in fishing-boats to collect the oil in buckets, which was then poured into storage-tanks. Since they had little or no protective equipment or were untrained in how to use what they did have, the long-term effects of their exposure to a mixture of chemical substances remains to be seen. It appears that the Dalian municipal government had only enough capacity to cope with 200 tonnes of oil, and less than the 1,500 actually spilt.
While this is nothing compared to the 750,000 tonnes of oil that poured into the gulf of Mexico, for which BP are taking part of the blame along with their subcontractors, the point is made that China needs to advance its capability to provide long-term solutions to environmental problems of this kind. There is currently a great lack of environmental and geochemical research into oil-spills in China. The Dalian oil-spill is likely to be a microcosm of greater future catastrophes for a highly populous country that is expected to expand its oil-based personal transportation by a factor of ten to 200 million by 2020.
Related Reading.
"China tackles its first major oil spill," Chemistry World, September 2010, p10.