Tuesday, April 17 — Track 1
|Tuesday, April 17, 2012 | | TRACK 1 || 11:00 AM — 12:15 PM|
Composting Emissions Analysis And Control
Something Is In The Air At Compost Facilities
John Cleary, Washington Department of Ecology
On April 25, 2011, Washington State Department of Ecology (Ecology) adopted a policy that all composting facilities regulated by Ecology's Air Quality Program and permitted to process more than 7,000 tons of feedstock per year need an air permit. Ecology's decision was based on ammonia vapors measured at a few compost facilities in California. However, limited data on compost vapors was available for Washington's compost facilities. This, combined with compost rule revision work, is driving Ecology to learn more about compost facility emissions, including odors, toxicity, sources and emission rates.
In June 2011, Ecology sampled compost emissions at two compost facilities; one facility on the west side and one on the east side of Washington. Both facilities volunteered to have Ecology sample at their sites. Because of the limited samples collected in this screening, results cannot be used to conclude that a site has an odor or toxicity problems. However, the results do give Ecology a snap-shot of what may be happening at large facilities that compost food waste and yard debris. It also provides baseline information which may inform the compost rule revision, and will help guide further study.
Delaying Pile Mixing To Reduce Methane Emissions
Walter Mulbry, USDA/ARS/EMBUL
The effect of the timing of pile mixing on greenhouse gas (GHG) emissions during dairy manure composting was determined using large flux chambers designed to completely cover replicate pilot-scale compost piles. Previous studies from different research groups have demonstrated that the majority of GHG emissions occur within the first three to four weeks of composting. Recent results using pilot scale dairy waste compost piles showed that GHG emissions from piles that were mixed four times during an 80 day trial were approximately 20% higher than emissions from unmixed (static) piles. In that experiment, carbon dioxide, methane, and nitrous oxide accounted for roughly 80%, 17%, and 3% of GHG emissions, respectively. The current experiments were designed to extend previous results by determining the effect of delaying the first mixing date on GHG emissions. Replicate piles containing approximately 2 m3 dairy waste were first mixed after 2, 3, 4 or 5 weeks. A final set of replicate piles was not mixed. Results from two separate trials showed that total methane emissions decreased significantly as the date of first mixing was delayed. Ultimate decisions to delay compost turning to reduce GHG emissions will have to be balanced against the schedule required for pathogen reduction.
Air Emission Control Techniques for Composting Operations
The major air emissions concern for compost facilities in North America is odor. However, facilities operated in California and some other parts of the United States are now being increasingly concerned about emitting VOCs, ammonia, greenhouse gases, ozone precursors, and even toxic compounds. This presentation is focused on VOCs and ammonia, but in general, will apply to odor emissions and other compounds of interest as well. In addition, the control technologies are applicable to greenwaste, food waste, biosolids, and animal manure composting.
Significant composting air emission reductions can occur just by implementation of more sophisticated compost management and aeration systems. By providing balanced nitrogen and carbon in the mix, controlling pile temperature, and assuring appropriate oxygen levels, air emissions can be reduced with no special additional hardware. For the situations where more control is needed, the currently available compost control strategies and control technologies that offer air emissions control include: Aerated Static Pile (ASP) with Biofiltration Layer Cover ? Positive Aeration; ASP with Manufactured Cover - Positive Aeration; ASP ? Negative Aeration with Biofiltration; Completely Enclosed ASP with Biofiltration.
In jurisdictions where the regulatory approach is based on control efficiency, regulatory compliance can get complicated. Most air regulators view control efficiency as the performance of some add on device, where the covered or controlled compost systems, the cover provides additional process benefits besides just a barrier to emissions. In most cases the air regulatory agency wants to know what is the control efficiency of the air emissions barrier, where the question that should be asked is what is the control efficiency of the entire system. The control efficiency of a covered system is thought to be better than just the control that the cover provides because of the positive collateral benefits that the cover provides, such as moisture and temperature control. This is further complicated because the standard for control can either be an actual measurement from the facility in question, or comparison to some standard generic baseline emission rate for the process. The most common way to express emissions in the compost industry is to normalize them to the actual wet tonnage of the initial mix, with the emission rate reported as pounds of emission per ton of initial mix of waste and amendment.
Available air pollution control strategies for reducing site emissions and the likely control efficiency of these generic options will be presented. In addition, a discussion will be included as to the 'pros and cons' of these various emission control strategies and how the fugitive air emissions from these strategies can be measured and used to assess the effectiveness of the control technology.
|Tuesday, April 17, 2012 | | TRACK 1 || 1:45 PM — 3:30 PM|
State Compost And Digester Rule Development
Oregon: Revised Rules Facilitate Food Scraps Composting
In September 2009, after a complex stakeholder advisory process, Oregon adopted new rules for regulating composting facilities, creating a risk-based regulatory system that tailors regulation to the potential harm at each facility. Public demand for food scraps composting has grown significantly in recent years. Since rule adoption and the stabilization of the regulatory landscape, composting facilities are investing in necessary site upgrades for managing food scraps. Oregon now has 11 facilities composting food scraps — and counting.
Washington: Revising Compost Rules, Regulatory Development For AD Operations
Chery Sullivan, Washington Department of Ecology
The Department of Ecology supports organics processing and management in Washington. The goal with this update is to ensure that composting and anaerobic digestion rules help facilities process materials and produce products that protect human health and the environment. In turn, good organics management practices encourage economic vitality for communities, and anaerobic digestion and compost related businesses in the state.
Ohio: "Decomposing" Regulatory Challenges To Food Scraps Composting
Joe Goicochea, Ohio Environmental Protection Agency
During the past two years, Ohio EPA has proposed legislative and regulatory changes to incentivize food scraps composting. Limited exemptions promote composting at community gardens, prisons, schools and any location, while changes in fees and schedules make it more affordable to start composting businesses. Additional changes in operational and monitoring rules ensure that these facilities operate in a manner that minimizes common environmental risks and sustain a productive composting industry in Ohio
|Tuesday, April 17, 2012 | | TRACK 1 || 4:15 PM — 6:00 PM|
Bioplastic Innovations And Developments
Producing Biodegradable Plastics From Biogas
Molly Morse and Anne Schauer-Gimenez, , Mango Materials
Mango Materials, a California-based start-up company, produces biodegradable plastics from waste biogas (methane) that are economically competitive with conventional petroleum-based plastics. Mango Materials uses excess methane gas from wastewater treatment plants or landfills to produce pellets of polyhydroxyalkanoate (PHA), a valuable polymer that is converted into a variety of high margin or high volume, eco-friendly plastic products such as children's toys, electronic casings, water bottles, and food packaging containers. Due to a rising preference for green products from both consumers and government agencies, demand for biodegradable and non petroleum-based plastics is growing rapidly. The competition uses either petroleum, which is low cost but produces non-biodegradable plastic, or sugars, which are expensive but produce biodegradable plastic. In contrast, Mango Materials uses affordable methane gas and a process that competes favorably with petroleum-based plastics to produce low-cost, biodegradable plastics. Mango Materials is in the process of scaling up from small bench top reactors to a demonstration facility that will produce commercial samples of PHA. This technology gives methane producers another profitable use for their waste biogas while transforming a greenhouse gas into a valuable commodity. This presentation will discuss the concept of using methane to produce a biodegradable plastic and the effort Mango Materials' team is putting into starting a company in the bioplastics space.
Plastic Bag Bans And Effects On Residential SSO Diversion
Massimo Centemero, Italian Composting Council and Christian Garaffa, Novamont SpA
Source separation of residential kitchen scraps is well developed in Italy and still growing. More than 20 million people (one third of the total population) are connected to an SSO program and 3.7 million metric tonnes per year of organics are source separated and recovered in composting or AD facilities, representing 35% of all MSW recycled. Source separation of kitchen scraps alone exceeds 2.1 million tons resulting in a major diversion factor from landfill. Since 2008, CIC (the Italian Composting Council) is continuously monitoring the quality of organics collected and delivered to composting facilities.
On January 1st 2011, Italy introduced a nation wide ban on non compostable plastic single use check out bags. To monitor and understand the effects of the ban on the quality of the feedstock collected in residential SSO programs, CIC started performing detailed analyses on the type of bags found in the source separated kitchen scraps; at the time being this investigation covers several municipalities equalling a population of about 4.5 million inhabitants.
The collected data distinguish between polyethylene plastic bags, compostable bags certified according to the European EN13432 standard and degradable (fragmentable) polyethylene bags; the survey shows the percentage use of these bags in SSO from north, central- and southern Italy. Best practice cases show a total contamination rate below 2% in weight. There is a clear link between the quality of the collected feedstock and a widespread use of compostable bags to collect organics.
On January 25th 2012, the Italian Government issued additional legislation improving the ban by unequivocally linking the terms biodegradable and compostable to the European EN13432 standard, by defining specific gauges to define the difference between single use and reusable bags and by setting a clear system of fines for violations. This new bill will further strengthen the synergies established by the non compostable plastic bag ban and the SSO programs throughout the country.
Bioplastics And Organics Compliance: Next Steps
Lindsay Fernandez-Salvador, OMRI
This presentation will discuss the current barriers to acceptance of bioplastics in compost for organic use, and how the industry could address those barriers in the future. Learn about this diverse group of products, and delve into the next steps toward an allowance for bioplastics in organic production. Attendees will learn about National Organic Standards Board (NOSB) petitions, what a petition for bioplastics might look like, and what to expect from the process.
Navigating The Complex World Of Compostable Plastics
Matthew Cotton, Integrated Waste Management Consulting, LLC