Scott

December 19, 2007 | General

BioCycle World


BioCycle December 2007, Vol. 48, No. 12, p. 6
Composting Project At England’s “Ham Wall” Generates More Than 300 Cubic Meters Of Organics
As reported in the Winter 2007 issue of Britain’s Composting News, Ham Wall is one of 200 nature reserves managed by the Royal Society for the Protection of Birds (RSPB), with a total of over 300,000 acres – and lots of composting potential. As one of the largest wetlands in South West England, the Ham Wall reserve is dominated by reed beds, parts of which need to be regularly cleared. Writes Sally Mills of the managing staff: “Burning waste vegetation is not only becoming less desirable (and harder) but leaving material to rot down has its own set of problems where it’s detrimental to water quality… Everything we do needs to be done with conservation in mind and composting is no exception.”
The reserve has been composting with an Ecopod in-vessel system for the last three years. To minimize carbon emissions, aeration for the Ecopod is provided by wind power with a back up generator. Continues Mills:
“The team at Ham Wall have been amazed at the results, how such reedy and rank vegetation can be turned into a useful product with high value. The compost performs well for seeds of all shapes and sizes – creating our wetlands of the future… As well as the intrinsically sustainable nature of composting, we have reinforced the sustainability message, by developing our packaging to encourage recycling by supplying our compost in a refillable, multipurpose bag.”
The composting team is carrying out demonstration events and sharing experiences with land managers, showing that composting is both a useful and successful technique for the disposal of waste material. Other contents of this latest Composting News issue cover management and control of compost liquid produced at sites, redesigning waste as a resource and reducing the amount of organics sent to landfills. Visit the website at: www.compost.org.uk, or e-mail: info@compost.org.uk.
International Biosolids Network
The International Biosolids Network is an exciting outgrowth of the international conference, “Moving Forward Wastewater Biosolids Sustainability: Technical, Managerial and Public Synergy,” held this past June in Moncton, New Brunswick, Canada. An agreement to form this global alliance was made during the Moncton conference. “As the first step towards creating such an alliance, the Greater Moncton Sewerage Commission (GMSC) will initially host the website intended to centralize and be a one-stop site of all the links, globally, relating to wastewater biosolids,” says Roland LeBlanc, Chairman of GMSC and Chair of the June conference. “These could be links to associations, users, operators, academics, government and regulatory agencies as well as any others that participants in the alliance feel should be included.”
The URL is: www.internationalbiosolidsnetwork.org. The site is set up as follows, explains LeBlanc: “Upon opening the website there will be displayed a map of our planet. By pressing on a continent, the countries of that continent will appear. By then pressing on the country the wastewater and biosolids links of that country will appear. By pressing on a link of interest you will be automatically linked to the website of that particular link.” To populate the website, especially in the countries, GMSC is asking for those interested to forward links they are aware of that would be useful to have referenced in this “global one-stop website.” Links and suggestions can be sent to: gmscpcp@nbnet.nb.ca.
Energy Production Costs For Farm Digesters
A technical report – “An Analysis of Energy Production Costs From Anaerobic Digestion Systems on U.S. Livestock Production Facilities” – was issued in October 2007 by the U.S. Department of Agriculture’s Natural Resources Conservation Service (NRCS). The publication reviews the potential of using manure anaerobic digestion (AD) systems to produce electricity or biogas to supply farm energy needs. An in-depth biogas production cost analysis is provided to assess the feasibility. It is based on 38 installations in the U.S., and was authored by Jenifer Beddoes and Kelsi Bracmort of NRCS, Robert Burns of Iowa State University and William Lazarus of the University of Minnesota. Both electricity and biogas costs from these systems were compared to the current U.S. cost of electricity, natural gas and liquid propane (LP) in dollars/gigajoule of energy content. The analysis shows that AD system capital costs can be reduced by approximately 36 percent if no electrical generation system is installed. The economic advantage of using biogas at the point of generation is more apparent in remote locations where the costs of natural and LP gas are higher than standard markets. The cost analysis presented suggests that lower cost AD systems currently employed on U.S. farms can provide biogas that is competitive or lower in cost than current U.S. commercial natural gas prices – if the biogas is used directly on site in space heaters or boilers without excessive additional gas upgrading (cleaning and conditioning) costs.
Explains the report’s summary: “Typically, the value of the energy alone produced by a manure AD system will not provide a positive cash flow given current U.S. energy costs. The combination of multiple benefits including energy value, odor control, by-product sales, carbon credit value and possible tipping fees for taking other materials (such as food waste) is the best approach to operating a manure digestion system with overall benefits that exceed system installation and operation costs. Producers should also consider the use of cost-share, grant monies or other support for the development of renewable energy sources that may be available to assist with the installation of manure AD systems. The offset of a portion or all of the digester capital costs can result in the ability to operate a digester system with a positive cash flow from energy sales alone. Based on the analysis completed in this study, the direct use on the farm for biogas produced via a manure AD system appears to be economically feasible when the on-farm heating requirements are high enough to utilize the biogas produced by the system.”
Toward Zero Waste In National Parks
International Paper, the National Park Foundation and the National Recycling Coalition launched a new pilot program in October to evaluate ways to limit the impact of foodservice products in America’s national parks. The study, funded in part by a donation of up to $1 million by International Paper, will commence in the summer of 2008 and is aimed at moving toward “Zero Waste” across the park system by identifying best practices in foodservice waste reduction that can be transferred to national parks throughout the country. Through an agreement with the National Park Foundation, International Paper will produce a customized cup for use by parks, concessionaires and others. The cup, International Paper’s fully compostable, recyclable ecotainer™, will display printed messages that will raise awareness about the National Park Centennial in 2016 and educate the public about conservation and environmental stewardship. International Paper will donate a penny for each commemorative cup sold (up to $1 million) back to the National Park Foundation to help fund a joint effort between IP, the National Park Foundation and the National Recycling Coalition to evaluate foodservice waste management practices and educate employees, concessionaires and visitors about ways to reduce waste in the parks.
Garbage From Sri Lanka’s Capital Sorted And Composted
Colombo, the capital city of Sri Lanka, has been sending approximately 1,000 tons/day of garbage to a dump in Bloemendhal for the past 20 years, reports the country’s The Sunday Times Online. In 2002, Burns Environmental and Technologies Limited (BETL) partnered with the Colombo Municipal Council’s Solid Waste Section to establish more responsible disposal. BETL processes roughly 500 tons/day of garbage at a composting site in the city of Sedawatta. According to Sumith Jayawardena, General Manager of BETL, the facility is the largest plant of its kind in South Asia.
Incoming garbage is manually sorted to remove as much plastic as possible, which is then washed and ground into pellets for items such as coat hangers and flower pots. Remaining material is put in piles to decompose for 60 days, turned once a week. The piles are covered with sawdust (for odor control), and technicians at the site monitor temperatures, to ensure 60°C is maintained. After 60 days, the material is put on a conveyor belt for a second round of manual sorting, before being sent to a trommel screen. Approximately 68 percent of the garbage taken in cannot be made into compost, which the General Manager notes would change if garbage were sorted at the point of production.
Erosion Control Compost Outperforms Straw Blankets
Findings of a research study that determined how blending wood mulch with compost may affect its performance as an erosion control practice relative to a straw blanket with polyacrylamide (PAM) were published in the Journal of Soil and Water Conservation (Vol. 62, Number 6; 2007). Researchers included Britt Faucette of Filtrexx International, Jason Governo of Compost Wizard, Carl Jordan at the Institute of Ecology and a team from Auburn University. Also analyzed in the research was if particle size distribution of the organic erosion control blanket affects runoff, erosion and vegetation establishment.
Notes the article abstract: “Researchers concluded that the greater percent of compost used in an erosion control blanket, the lower the total runoff and the slower the runoff rate. Compost erosion control blankets retained 80 percent of the simulated rainfall applied and reduced cumulative storm runoff by 60 percent, while the wood mulch blankets reduced runoff by 34 percent and straw with PAM by 27 percent. Conversely, the greater the percent of mulch used in the erosion control blanket, the lower the sediment and suspended sediment load. However, any combination of compost and mulch reduced runoff volume, runoff rate, and soil loss relative to a straw blanket with PAM. The average cover management factor (C factor) for the straw with PAM was 0.189, the compost blanket was 0.065, and the mulch blanket was 0.013. Researchers also concluded that particle size distribution of the compost and mulch blankets was the leading parameter of the reduced soil loss and runoff. If particle size distribution specifications are not followed, total soil loss can be four times greater, suspended solids can be five times greater, and turbidity can be eight times greater, relative to blankets that meet particle size distribution specifications.” Several erosion control blanket specifications were analyzed. Data were provided about total Kjeldahl nitrogen loading from the erosion control tools tested compared to the control (bare soil): 8,000 percent increase from the straw blanket with fertilizer; 340 percent from the compost blanket; and 18 percent for the mulch blanket.


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