Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Landfill Cover Soil Methane Oxidation Underestimated

28.04.2009
A literature review reveals that landfill cover soils oxidize more methane than guidelines suggest.

Landfilled waste decomposes in the absence of oxygen and results in the production of methane. Landfills are classified as the second-largest human-made source of CH4 in the U.S. Additionally, landfill gas contains numerous non-methane hydrocarbons that are either volatilized directly from waste materials or produced through biochemical reactions during waste degradation.

Microbial methane oxidation reduces the emissions of methane and other volatile hydrocarbons from landfills. Determining the importance of this process is one of the major uncertainties in estimating national or global CH4 emissions from landfills. Landfill gas that is not collected passes through landfill cover soils on the way to being released to the environment. Bacteria in the soil consume methane and other volatile hydrocarbons that are produced by decomposition in the underlying waste by reacting it with oxygen.

A value of 0 to 10% oxidation has been recommended by the Intergovernmental Panel on Climate Change guidelines for national greenhouse gas inventories. Currently, for regulatory purposes the USEPA has recommended a default value for landfill cover CH4 oxidation of 10% due to the uncertainty involved and the lack of a standard method to determine oxidation rate.

Drs. Jeffrey Chanton, David Powelson, and Roger Green of Florida State University and Waste Management Inc. reviewed and compiled literature results from 42 determinations of the fraction of methane oxidized and 30 determinations of methane oxidation rate in a variety of soil types and landfill covers. The results were published in the March-April issue of the Journal of Environmental Quality. The means for the fraction of methane oxidized upon transit across the differing types of soil covers ranged from 22% in clayey soil to 55% in sandy soil. The overall mean fraction oxidized across all studies was 36% with a standard error of 6%. For a subset of fifteen studies conducted over an annual cycle the fraction of methane oxidized ranged from 11 to 89% with a mean value of 35 ± 6%, a value that was nearly identical to the overall mean.

The literature summarized in this paper indicates that the fraction of methane oxidized in landfill cover soils is considerably greater than the default value of 10%. Of the 42 determinations of methane oxidation only four reported values of 10% or less. One reported a value of 10%. This particular study was the first to report a well constrained value for the fraction of methane oxidized in a specific landfill, and because of this, it has received undue weight in the determination of regulations. The default value of 10% should be updated based upon technological advancements in soil engineering and state-of-the-practice applications in cover design as well as recent studies detailed journals such as Journal of Environmental Quality.

The full article is available for no charge for 30 days following the date of this summary. View the abstract at http://jeq.scijournals.org/cgi/content/abstract/38/2/654.

The Journal of Environmental Quality, http://jeq.scijournals.org is a peer-reviewed, international journal of environmental quality in natural and agricultural ecosystems published six times a year by the American Society of Agronomy (ASA), Crop Science Society of America (CSSA), and the Soil Science Society of America (SSSA). The Journal of Environmental Quality covers various aspects of anthropogenic impacts on the environment, including terrestrial, atmospheric, and aquatic systems.

The American Society of Agronomy (ASA) www.agronomy.org, is a scientific society helping its 8,000+ members advance the disciplines and practices of agronomy by supporting professional growth and science policy initiatives, and by providing quality, research-based publications and a variety of member services.

Sara Uttech | EurekAlert!
Further information:
http://www.agronomy.org

More articles from Agricultural and Forestry Science:

nachricht New research recovers nutrients from seafood process water
31.10.2018 | Chalmers University of Technology

nachricht Plant Hormone Makes Space Farming a Possibility
17.10.2018 | Universität Zürich

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Epoxy compound gets a graphene bump

14.11.2018 | Materials Sciences

Microgel powder fights infection and helps wounds heal

14.11.2018 | Health and Medicine

How algae and carbon fibers could sustainably reduce the athmospheric carbon dioxide concentration

14.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>