Walk the Walk

I have posted numerous time on this blog about biofuels and the need for us to start using them. I have also stated that it is possible for biofuels especially Biodiesel to be produced from Agricultural wastes. When I have made these statements I have usually linked to the company that is developing the technology, not a company that is actually doing it.

Well I thought it was about time to highlight an actually working example of what I've been talking about. Please read the article below.

Paired processes aim to fuel biodiesel buildup

ChemicalProcessing.com

The first plant to go from biomass to syngas to biodiesel is slated for 2007 startup. Once started up early next year, the unit will feed in 75,000 mt/yr of wood chips and straw to make so-called SunDiesel.

A 15,000-metric-ton/yr demonstration plant now being built by Choren Industries, Freiberg, Germany, will be the first plant to convert biomass into syngas that then will be turned into high-quality diesel fuel. Once started up early next year, the unit will feed in 75,000 mt/yr of wood chips and straw to make so-called SunDiesel.

The fuel can be used without modification in any diesel engine without compromising performance, claims the company. Moreover, says Choren, it is virtually free of sulfur and aromatics, so it burns cleaner without particulate emissions. It can be used on its own or blended with conventional diesel fuel.
Choren has operated a 2,000-mt/yr pilot plant for SunDiesel since October 2003; Shell now holds a greater-than-25% stake in the firm; automakers Volkswagen and DaimlerChrysler also are cooperating in the development.

Choren is teaming its Carbo-V biomass gasification process to convert biomass into synthesis gas with Shell’s latest-generation Fisher-Tropsch gas-to-liquids (GTL) technology, called the Shell Middle Distillate Synthesis (SMDS) process, to turn the syngas into biodiesel. Shell now is operating the first commercial plant using the SMDS technology in Bintulu, Malaysia; output is used in the production of V-Power Diesel, which is already available in Europe and is proving itself in auto racing.

Biomass gasification

Unlike conventional processes for biofuels, which use grain and other food crops as feedstocks, the Carbo-V process starts with agricultural wastes, such as wood chips, rice husks and straw, or trees specifically grown for energy production.

Traditional gasification systems aren’t suitable for making syngas from biomass, says Choren, because their physical design limits operation to around atmospheric pressure and 1,000°C. This leads to significant tar and methane in raw gas, which can pose difficulties in subsequent Fisher-Tropsch processing. Also, the systems cannot cope with varying feedstock sizes and quality, the company contends, and so only can handle restricted ranges of biomass sources.

The Carbo-V process gets around these drawbacks by processing the biomass in three stages: pre-conditioning, partial oxidation and chemical quenching.

First, the biomass feeds are blended and then dried to a water content of 15% by weight. This feedstock goes to a low-temperature gasifier, in which it smolders in a mix of O2, CO2 and steam at 400°C to 500°C and 5 bar. The biomass is broken down into volatile gases and char. The gases pass to a combustion chamber in which tars and long-chain hydrocarbon molecules are decomposed at temperatures above 1,400°C. Meanwhile, the char is ground and milled into a powder that is blown into the hot gases exiting the combustion chamber. This chemical quenching reduces gas temperature to about 900°C and contributes to the process’s high cold gas efficiency of over 80%, says Choren.

The Carbo-V gasifier yields syngas as well as significant amounts of steam and heat, some of which is used to dry the incoming feed. Choren says that overall thermal efficiency exceeds 90%.

Because the syngas may contain traces of sulfur and other contaminants that could poison Fisher-Tropsch catalysts, it is sent through scrubbers before going to the GTL unit.

If all goes well with the demonstration plant, Choren plans to build a full-scale (200,00 mt of SunDiesel per year) plant at Lubmin, Germany, for 2009 start up, followed by similar-sized plants elsewhere in Germany.

The company also is interested in installing plants in China and the U.S.

Dr David Karoly

Below is an Article by David Karoly an Australian professor in Meteorology. It doesn't present any citation like George Monbiot but It is rather convincing.

David Karoly
David Karoly is an ARC Federation Fellow and Professor of Meteorology in the School of Earth Sciences at the University of Melbourne. He was heavily involved in the preparation of the IPCC Fourth Assessment Report, released in 2007. He is a member of the Wentworth Group of Concerned Scientists.

Climate change science misinformation

Science is about developing an understanding of natural and physical systems and testing that understanding using observations and modelling. Questioning and scepticism are fundamental aspects of science. Scientific theories are accepted understandings that have stood the test of time after extensive critical analysis.

The arena for proposing new scientific ideas and their subsequent testing is through peer-reviewed scientific journals. New science is not based on a single scientific publication, but on the accumulation of evidence from many published studies.

Over the last two decades, there have been thousands of peer-reviewed scientific studies of climate variability and change, leading to understanding of the causes of recent global warming. This understanding is reported in the assessments of the Intergovernmental Panel on Climate Change (IPCC), as well as by other scientific bodies including the US National Academy of Sciences, the British Royal Society, the US Climate Change Science Program, and the Australian Academy of Science.

Over the last decade, they have all reached the same conclusion - the observed increase in global-average surface temperature since the mid-20th century is mainly due to the increase in greenhouse gases in the atmosphere caused by human activity.

Recently, there has been an increase in opinion pieces in the media questioning the scientific understanding of global warming. This is not reflected in a surge of scientific publications suggesting that increasing greenhouse gases are not the cause of recent global warming. Instead, the vast majority of scientific studies support and strengthen this conclusion.

I do not know the reason for this increase in media coverage of so-called "global warming sceptics", where a common trend is to select a small amount of information to give credit to a misleading conclusion. Whatever the agenda, they have a number of common statements.

The IPCC is a political body and does not provide balanced assessments. This is untrue. While the members of the IPCC are government representatives, its assessment reports are written by hundreds of scientific experts from many fields. These reports are required to be policy-neutral and contain no recommendations. Each report takes more than three years to prepare and goes through multiple stages of independent expert and government review. This is the most thorough review process undertaken for any scientific assessment.

Carbon dioxide is such a minor atmospheric constituent that it can't affect global climate. This is untrue. While carbon dioxide makes up only 0.038% of the atmosphere, it is vital in the energy balance of the Earth's surface and atmosphere. If the atmosphere contained no greenhouse gases, the surface temperature would be about 30C colder.

The most important greenhouse gas is water vapour, but its concentration is determined by the temperature of the atmosphere and not emissions from human activity. Carbon dioxide concentrations in the atmosphere vary due to natural and human sources.

Temperature increases from ice ages to interglacial periods occur before increases in carbon dioxide, so carbon dioxide increases don't cause warming. This is another false conclusion. Temperature increases from ice ages to interglacial warm periods over the last half million years are initiated by variations in the Earth's orbit around the Sun, leading to changes in the amount of sunlight in summer at high latitudes.

These temperature increases are followed by increases in atmospheric concentrations of carbon dioxide, as the warmer ocean waters lose some dissolved carbon dioxide. However, the warmth of interglacial periods is only possible with the warming influence of the carbon dioxide increases, which amplifies the initial warming.

Increases in carbon dioxide over the last hundred years are due to natural sources This is another untruth. The observed increase in carbon dioxide in the atmosphere is due to burning fossil fuels, industrial activity and land clearing.

Observed changes in the relative abundance of different isotopes of carbon in carbon dioxide and small reductions in the amount of oxygen in the atmosphere are not consistent with natural sources, such as volcanoes or losses from the ocean. Observed carbon dioxide concentrations are now 30% higher than any time over the last half million years.

Global average temperatures have dropped from 2002 to 2008, while carbon dioxide has increased, so carbon dioxide can't cause long-term warming. This is another false conclusion. There are large natural year-to-year variations in climate. The warming influence due to increasing greenhouse gases is at global scales and cumulative over many years.

At short time scales, natural variability can offset that warming influence and cause short-term cooling. Global average temperatures have fallen over the last six years, due to natural variations, with the warmth in 2002 and in 1998 due to El Niño events and the recent La Niña causing colder temperatures in 2007 and 2008. The long-term warming trend is unequivocal.

Climate models are untested and unreliable. This is untrue. Global climate models are important physically-based tools for studying climate variability and change, with more than twenty different models developed independently around the world. They simulate well the magnitude of observed global-scale temperature variations. The long-term warming trend over the 20th century simulated by climate models agrees with that observed only when increasing greenhouse gases are included in the models.

The observed spatial pattern of warming does not show the fingerprint of increasing greenhouse gases. This is not true. The spatial fingerprint of the response to increasing greenhouse gases includes warming at the surface and in the lower atmosphere and cooling in the upper atmosphere, with larger warming at the surface in high latitudes and in the tropics at heights around 10km.

This spatial fingerprint agrees well with the observed pattern of surface temperature changes over the last hundred years and with temperature changes up to heights of 30km over the last four decades, when observational data are available. Any differences between the observed pattern and the greenhouse fingerprint are consistent with natural climate variability.

The best explanation for recent global warming is variations of the sun or cosmic rays. This is untrue. The spatial pattern of responses to increasing solar intensity is warming at the surface and warming in the upper atmosphere, which is not consistent with the observed cooling in the upper atmosphere.

Increasing solar intensity is also not consistent with the observed greater warming in winter and at night, when sunlight is less important. There are no observed increases in solar intensity or in cosmic rays over the last three decades, a period of pronounced global warming. The largest variations of solar intensity and in cosmic rays are associated with the eleven-year solar sunspot cycle. However, global-average temperature shows a long-term trend and no pronounced eleven–year cycle linked to the sunspot cycle.

In summary, let me emphasise that the pattern and magnitude of observed global-scale temperature changes since the mid-20th century cannot be explained by natural climate variability, are consistent with the response to increasing greenhouse gases, and are not consistent with the responses to other factors. Hence, it is very likely that increasing greenhouse gases are the main cause of the recent observed global-scale warming.

Evidence

If you want to see evidence for global warming you need to see this 4 Corners Program on the Arctic.

http://www.abc.net.au/4corners/special_eds/20080804/arctic/default.htm

Happy Birthday

Happy Birthday to Dad. Sorry I haven't called I'm a bit slack at the moment