Waste 360 will host its Global Waste Management Symposium 2020 at the Hyatt Regency Resort & Spa in Indian Wells, California, February 23-26, 2020.
The conference will feature world-class content, including innovative presentations by top industry experts; think technology, trends, critical issues, and scientific innovation; state-of-the-art breakthrough research; and showcases by leading suppliers of the latest solutions to the industry’s challenges. SCS Engineers professionals speaking this year include the following:
James Law will provide an Overview of ISWA’s Global Initiative on Closing Dumps, on Monday, February 24 at 2:00 pm (Track B: Waste Management Planning & Odor Control).
Alex Stege will evaluate the Local Effects of California’s Senate Bill 1383: Changes to Organic Waste Disposal & Impacts on Methane Generation, Recovery, and Emissions on Monday, February 24 at 2:00 pm (Track C: Organic Management Policy/Strategies).
Dr. Viraj DeSilva will deliver a presentation on PFAS Treatment – The Devil We Know and Need to Manage, on Tuesday, February 25 at 8:30 am (Track A: PFAS Management).
Dr. Gomathy Iyer will discuss the Suitability of Un-Composted Grass Clippings and Biosolids as Biocovers for Biological Methane Removal from Landfills on Tuesday, February 25 at 8:30 am (Track B: Landfill Covers).
Ray Huff will demonstrate The WAG: An Innovation in Landfill Gas Data Analysis on Tuesday, February 25 at 1:30 pm (Track B: Landfill Gas Management) and at the Fugitive Air Emissions Workshop on Wednesday, February 26 at 10:00 am.
Pat Sullivan will provide a Comparison of Organic Waste Management Options in Terms of Air Quality and GHG Impacts on Tuesday, February 25 at 3:30 pm (Track A: Life Cycle Assessment).
The Environmental Research & Education Foundation (EREF) is a strategic partner of this conference to deliver a program that is more technical, innovative and essential than ever before. The core education of GWMS is the submission of comprehensive abstracts in all areas related to solid waste engineering and management that have been vetted by GWMS’s committee of industry experts. The presentations will be given by researchers from top academic institutions and industry experts.
Dr. Iyer is a Staff Professional at SCS focusing on environmental research and engineering in water, wastewater, solid waste, and landfill design. Gomathy is another of our remarkably talented young professionals utilizing her expertise in leachate management and landfill design to support her clients.
We hope you will attend Gomathy’s presentation “Suitability of Un-Composted Grass Clippings and Biosolids as Biocovers for Biological Methane Removal from Landfills,” on Tuesday, February 25 at 8:30 am (Track B: Landfill Covers), at the 2020 Global Waste Management Symposium. Her presentation is based on a technical paper of the same name and co-authored with Melanie Sattler of the University of Texas at Arlington, and Darrin Dillah of SCS Engineers.
Landfill biocovers are widely used to oxidize methane emissions, a known greenhouse gas. The biocovers in use today are typically either fully or partially made of composts. However, the production of compost, although theoretically an aerobic process, also produces potentially substantial quantities of methane, from 3.2 to 362 kg carbon dioxide (CO2)-equivalents per ton of wet waste composted, depending on various factors, for example, the type of waste, and open or enclosed composting technology. This research explored the suitability of using uncomposted grass clippings as a biocover for methane removal from landfills, with the aim of reducing net greenhouse gas emissions.
Physical and chemical characteristics of grass clippings along with other components of yard waste were studied and compared. The use of biosolids and fly ash as potential bulking materials were considered since the physical and chemical characteristics of biosolids and fly ash complemented the grass clippings and biosolids were expected to provide a good inoculum of microbes for the biocover. Batch tests were performed on the grass clippings and combinations of grass, biosolids and fly ash mixtures for aerobic methane removal. Grass clippings were found to have a maximum methane removal rate of 2,121.7 nmol/kg/s, and a combination of grass and biosolids showed a maximum methane removal rate of 4,410.8 nmol/kg/s. Analyzing different proportions of grass, biosolids and fly ash mixtures, it was found that a 70% grass, 21% biosolids and 9% fly ash mixture exhibited the highest methane oxidation of 5,862.5 nmol/kg/s.
Column tests were performed on the grass clippings and on a combination of 70% grass, 21% biosolids and 9% fly ash by introducing a continuous flow of 50% methane and 50% carbon dioxide at the bottom of the column reactor containing 2 feet of biocover material. The column reactors with grass clippings showed a methane removal of 90-100% within the first 10 days, and the reactors with the combination of grass, biosolids and fly ash showed a methane removal of 90-100% within first 3 days. Biocover performance indexes were calculated based on the performance of each biocover. The biocover performance index for grass was found to be 20.8 µg/g/hr and that for the combination of 70% grass, 21% biosolids and 9% fly ash was found to be 43.3 µg/g/hr.
Representative samples were taken from the column reactors to analyze for the presence of methanotrophs involved in the methane removal process. A PCR (Polymerase Chain Reaction) analysis was performed on these samples with A189 (forward) and A682 (reverse) primers. The evidence of pMMO PCR amplification products was seen in all column reactor samples, indicating the presence of the pMMO gene, which is found in methanotrophs and hence confirmed the presence of methanotrophs. A BLAST (Basic Local Alignment Search Tool) was performed on the sequence obtained from the PCR analysis confirmed methalocystis and type 2 methanotrophs. Figure 1 shows the gel picture of the PCR analysis of the column reactor samples. #1
LEAF testing was conducted to analyze the leachability of fly ash in the biocover. It was seen that silver, arsenic, cadmium, chromium and thallium exceeded the permissible level in drinking water. Hence, it was concluded that the grass clippings by itself or a combination of grass and biosolids can be used as a biocover for biological methane removal.
Global Waste Management Symposium 2020
February 23 @ 8:00 am – February 26 @ 5:00 pm
2020 GWMS Information