Comments on: Totally clean and green by 2030? http://futurity.org/earth-environment/totally-clean-and-green-by-2030/ Research news from leading universities Fri, 12 Mar 2010 06:40:05 -0400 http://wordpress.org/?v=2.8.4 hourly 1 By: Eric B http://futurity.org/earth-environment/totally-clean-and-green-by-2030/comment-page-1/#comment-2758 Eric B Tue, 01 Dec 2009 15:19:10 +0000 http://futurity.org/?p=5084#comment-2758 Good summary of the article, but time would be better spent reading the comments to the actual article, which pretty thoroughly and with good evidence, rip it to shreds: http://www.scientificamerican.com/article.cfm?id=a-path-to-sustainable-energy-by-2030#comments While following links related to this, I found this post, and this interesting article on "The Chemistry of Personalized Solar Energy" which seems more promising than what Jacobson and Delucchi talk about: http://pubs.acs.org/doi/abs/10.1021/ic901328v Good summary of the article, but time would be better spent reading the comments to the actual article, which pretty thoroughly and with good evidence, rip it to shreds:

http://www.scientificamerican.com/article.cfm?id=a-path-to-sustainable-energy-by-2030#comments

While following links related to this, I found this post, and this interesting article on “The Chemistry of Personalized Solar Energy” which seems more promising than what Jacobson and Delucchi talk about:

http://pubs.acs.org/doi/abs/10.1021/ic901328v

]]> By: Greg Hawk http://futurity.org/earth-environment/totally-clean-and-green-by-2030/comment-page-1/#comment-1931 Greg Hawk Mon, 16 Nov 2009 17:46:49 +0000 http://futurity.org/?p=5084#comment-1931 The analysis leaves out the elephant in the room, i.e. the vast amounts of resources discarded into landfills and therefore unavailable to be processed into new goods at a fraction of the energy needs and carbon footprint compared to manufacturing products from virgin materials. However, there is hope in the form of mining landfills and processing current municipal waste streams in a low environmental impact way that recovers many of those resources, produces electricity, dramatically reduces the potential of future groundwater and air pollution problems as the landfills' caps and liners degrade, sequesters carbon and reclaims and builds stable land for development. The process is continuous pyrolysis wherein the waste is heated in the absence of oxygen to 550 degrees C to thermally decompose the organic matter into a condenseable liquid fraction, i.e., oil, and a non-condenseable fraction that can be readily cleaned up and then burned to generate electricity. Waste heat is used to help dry the waste. Metals are recovered from the processed solid waste. The remaining waste is dry, inert and contains a substantial amount of elemental carbon. This carbon is not bioavailable and is therefore sequestered when placed back into the landfill. It is also free of toxic organics such as pesticides and petroleum solvents. Since the non-condenseable gas to be burned to generate electricity and waste heat for the process only occupies about 4% of the volume of gas as compared to the volume of polluted gas cleaned up in air pollution control equipment at large commercial waste to energy incineration plants, the cost to clean up the non-condenseable gases from a continuous pyrolysis plant is far less. The huge gas volume reduction is due to the absence of air from the process until after the gas has been cleaned. In addition, the pyrolysis plant burns cleaned gas, not garbage. Sounds like a great idea right. So why haven't we heard much if anything about this technology? The analysis leaves out the elephant in the room, i.e. the vast amounts of resources discarded into landfills and therefore unavailable to be processed into new goods at a fraction of the energy needs and carbon footprint compared to manufacturing products from virgin materials. However, there is hope in the form of mining landfills and processing current municipal waste streams in a low environmental impact way that recovers many of those resources, produces electricity, dramatically reduces the potential of future groundwater and air pollution problems as the landfills’ caps and liners degrade, sequesters carbon and reclaims and builds stable land for development.

The process is continuous pyrolysis wherein the waste is heated in the absence of oxygen to 550 degrees C to thermally decompose the organic matter into a condenseable liquid fraction, i.e., oil, and a non-condenseable fraction that can be readily cleaned up and then burned to generate electricity. Waste heat is used to help dry the waste. Metals are recovered from the processed solid waste. The remaining waste is dry, inert and contains a substantial amount of elemental carbon. This carbon is not bioavailable and is therefore sequestered when placed back into the landfill. It is also free of toxic organics such as pesticides and petroleum solvents.

Since the non-condenseable gas to be burned to generate electricity and waste heat for the process only occupies about 4% of the volume of gas as compared to the volume of polluted gas cleaned up in air pollution control equipment at large commercial waste to energy incineration plants, the cost to clean up the non-condenseable gases from a continuous pyrolysis plant is far less. The huge gas volume reduction is due to the absence of air from the process until after the gas has been cleaned. In addition, the pyrolysis plant burns cleaned gas, not garbage.

Sounds like a great idea right. So why haven’t we heard much if anything about this technology?

]]> By: manu http://futurity.org/earth-environment/totally-clean-and-green-by-2030/comment-page-1/#comment-1302 manu Tue, 27 Oct 2009 06:55:18 +0000 http://futurity.org/?p=5084#comment-1302 very good article..... i am just an undergrad student. i can potentially use this news.... like make a b-plan to cash upon this phenomenon.... love u futurity. very good article….. i am just an undergrad student. i can potentially use this news…. like make a b-plan to cash upon this phenomenon…. love u futurity.

]]>