Geoffrey Hill

Geoffrey Hill

Geoffrey Hill

Speaker | Geoff Hill, PhD

Shoreline, WA | geoffbhill@gmail.com

Geoff started his career in composting as a PhD research scientist analyzing pathogen destruction and compost process inhibition at UBC. Shortly after his PhD he was hired to run one of the largest composting and anaerobic digestion facilities in North America in Richmond BC for Harvest Power. The same process inhibition factors he studied during his PhD were evident at batches 1,000,000 times larger at the industrial scale.  Geoff has been successful in all aspects of organics consulting from design and Project Management of compost facility construction, through to source testing and approval of new source test methods in the Bay Area.

Session Code: A3

Track: Current Research (hosted by CREF)

Session Name: PFAS and AIr Emissions

Session Time: 4:15 to 5:45 PM

Presentation Title: Measuring Compost VOC Emissions – A New Approach

Presentation Description: This paper presents insights related to HDR’s recently published study commissioned by CalRecycle to explore VOC emissions from composting operations.

California’s Senate Bill 1383 requires 75% of organic material be diverted from landfills to reduce climate related impacts associated with landfill operations.  As California composters prepare to manage increased amounts of organics containing elevated levels of food waste, CalRecycle seeks to provide guidance in terms of the compost process and the Volatile Organic Compounds that it produces. This paper will provide an overview of the Composting Volatile Organic Compounds Emissions Guide the HDR Team prepared for CalRecycle.

The key objectives of this research study were:
1.  Clarify the importance of oxygen availability (or lack thereof) on biological decomposition (and decomposition oxidation pathway), odor generation, and VOC production.
2.  Elucidate other key compost process parameters which can be taken into consideration and affect the design, operation, and optimization of the compost process,
3.  Evaluate an alternative method of measuring VOC emissions which is simpler to use and more cost-effective than the flux chamber method.
This presentation will discuss the methods used, the results gathered and provide an analysis of the conclusions, focusing on BMPs composters can use to reduce VOCs during composting. The project team gathered data from operating aerated static pile facilities using a novel “”hood”” method prior to lab analysis. Compost operating parameters (temperature, oxygen, pH, etc.) were gatheredat time of sampling to try to understand relationships and interconnectivity. Some testing was done “”piggy-backing”” with traditonal flux chamber methods
 Final Report will be available on CalRecycle website.