Thursday 26 February 2009

Gasification of Biomas from Wood Pellets to Algae

Wood pellets - when compressed these hold together well - but concern arises when they become wet



Gasification of biomass, which is a renewable and sustainable energy source, is a promising alternative to using fossil fuel based fuels, at high and extremely variable cost. Energy sources will come from an increasing list of biomass resources - sources of energy which have gone largely ignored and unused for more than 50 years. The list is likely to be so wide that even algae are likely to be produced to meet the demand for cheap and sustainable green energy in the future.





LIVE EVENT David James - Gasification of Algae - Green Fuels. Watch it now!








Combining the application of biomass gasification - where a mixture of mainly hydrogen and carbon monoxide is generated - with fuel cells - where the hydrogen is electrochemically converted into electricity - offers a highly efficient and incredibly flexible energy source. Gasification systems basically consists of a gasifier unit, purification system and energy converters - burner or engine.



Wood Pellet Gasification



In one not atypical gasification system fuel, initially wood pellets, is supplied from an indoor wood pellet storage site into the gasification plant. The fuel is fed through lock hopper systems by feeding screws into the lower section of the gasifier’s fluidized bed.



Fuels which can be used without difficulty include ground seed corn, switchgrass, cornstover, RDF (refused derived waste - subject to licensing constraints), woodchips, and sawdust to name just a few. The gasifier is a fluidized bed gasifier meaning that a tube of sand (the bed) is mixed (fluidized) by passing air through holes in the bottom plate of the tube.



Producer gas is created in the gasifier and this isa  fuel gas and chemcial source which can be used to replace fossil fuels in a wide range of devices, including road and rail transport.



Other devices which could be retrofitted with gasifiers are furnaces for melting non-ferrous metals and for heat treatment, tea dryers, ceramic kilns, boilers for process steam and thermal fluid heaters. Producer gas can also commonly be used for commercial cooking applications.



Gasification of wood and wood-type residues and waste in fixed bed or fluidised bed gasifiers with subsequent burning of the gas for heat production is state of the art in Northern Europe. However, the market has hardly yet been expoited aven in those countries where the wood gasifiers which are employed in the Scandinavian countries are used almost almost entirely just for heat generation.



Biomass is a sustainable energy resource which is destined to play an important role in future energy production and as an organic chemical raw material supply source, with biomass gasification the most promising conversion technology and very effective in reducing greenhouse gas emissions.



Biomass is converted into a gaseous mixture of hydrogen, carbon monoxide, carbon dioxide, and other compounds by applying heat under pressure in the presence of steam and a controlled amount of oxygen (in a unit called a gasifier). The biomass is broken apart chemically by the gasifier's heat, steam, and oxygen, setting into motion chemical reactions that produce a synthesis gas, or "syngas"-a mixture of primarily hydrogen, carbon monoxide, and carbon dioxide. It is this synthesis gas which can then be further reacted and refined to replace oil as a raw material for use in refineries.



Finally, we said that we would be telling you about the, improbable as it may seem, use of algae as a biomass energy source.



Algae Energy Farms



Algae energy farms which might be light enough to be integrated into large, flat rooftops and could therefore be present even right in the centre of our cities could be manufacturing green energy from the sun on a daily basis. If factory and commercial buildings could support the carbon recycling systems on-site, the waste heat and other byproducts of the carbonizer and fuel cell could be used for industrial process heat or space heat. In addition algae has been a hot topic lately as a possible solution to most of our fuel and food needs. Nearly half of an alga's mass is made up of lipids (a major component of vegetable oil) that can be used in the production of biofuels, and all sorts of plastic and the chemicals now made from oil.



So, if someone you know suggests that you should consider using gasification in some way, don't just laugh and dismiss him as a crank. He just could be right!


Steve Evans is an anaerobic digestion and methane energy enthusiast. Far from being despondent about rising gas prices he sees it as a great opportunity for us to start using clean renewable wind turbine energy which is usually to be found all around us. Also visit the < a href="http://www.dog-breeds.me.uk">dog breeds web site.

2 comments:

  1. Since 1996, I have been researching the harm to human health and the environment from the landspreading of sewage sludge "biosolids". http://www.sludgevictims.com

    We support the concept the utilizing sludge as a renewable resource to produce clean power and energy. However, some people - who agree landspreading sludge is harmful - nevertheless oppose thermal sludge treatment, such as gasification. They claim the air emissions are just as harmful as sewage sludge incinerators. Can you comment ?

    Thank you. Helane Shields, PO Box 1133, Alton, NH 03809

    ReplyDelete
  2. Hi, Thanks for sharing about biomass machine and gasifier, It’s very valuable for us.

    ReplyDelete