Driven by legislation in California (SB1383) in 2022, Santa Barbara County’s Anaerobic Digester Facility (ADF) began operating to generate renewable energy from the organic portion of Municipal Solid Waste (MSW). This waste was processed and recovered at the County’s Materials Recovery Facility (MRF) located at the Tijiguas Landfill. At the ADF, the organic material underwent a 28-day anaerobic digestion process.
At the ADF, the organic material underwent a 28-day digestion process. During this time, 50 per cent of the material was recycled back to the beginning of the process, while the remaining 50 per cent was sent for further composting using an open windrow method. The goal was to convert the residual digestate into high-quality, sellable compost.
Management recognised the need to retrofit the operation due to site constraints related to odour control, stormwater management, and litter management associated with open windrow composting methods. The retrofit aimed to eliminate odours and enhance process control. Since odour reduction was the most critical issue, management selected Sustainable Generation, which features the SG MOBILE System with GORE Cover, for a pilot study.
“GORE Cover has over 20 years of experience composting digestate as an additive to existing composters for FOGO, as well as acting as the after-treatment post-AD treatment for finishing digestate to control odour, moisture, re-hygienise, and produce high-quality compost,” says Brian Fuchs from W.L. Gore & Associates.
Santa Barbara County conducted an evaluation comparing the SG MOBILE System with GORE Cover against existing open windrow technology and a competing Aerated Static Pile (ASP) system. The competitor failed to meet performance expectations and could not provide any performance data.
The study focused on five key objectives:
- Odour mitigation;
- stormwater control;
- litter control;
- recipe optimisation; and
- compost quality.
In February 2023, Sustainable Generation delivered a demonstration unit, and composting operations began within days. Over a 90-day period, multiple batch tests were conducted to validate the system’s effectiveness. Third-party independent testing confirmed results, including:
- A 97.5 per cent odour reduction.
- A 98 per cent reduction in VOC emissions.
- Clear separation of stormwater from leachate during adverse weather events, including atmospheric rivers from the Pacific Ocean.
- Maintained PRFP temperatures.
- Production of stable, high-quality compost.
These results demonstrated the system’s ability to transform organic waste into premium compost while mitigating environmental impacts.
Full-scale implementation
Following the success of the pilot project, Santa Barbara County moved towards full-scale implementation. Within ten months, the site transitioned to an operational 20-heap SG MOBILE System processing 100,000 tonnes per year. The upgraded system improved site conditions, addressed odour concerns, minimised litter accumulation, and enhanced stormwater management.
As of July 2024, county officials reported that odour issues associated with the composting process had been effectively eliminated. Additionally, the project has reduced ecological impacts on the surrounding coastal area while increasing operational efficiency, setting a new standard for sustainable waste processing.
A model for future sustainability
“In the fast-evolving landscape of technology and business, swift decision-making is paramount,” said Scott Woods, founder and CEO of Sustainable Generation. “The SG MOBILE System addresses this necessity by providing a robust solution designed for rapid deployment and expedited data collection.
“This system aids in proof-of-concept processes and accelerates economic buyer decision-making. Coupled with our professional services staff, and remote serviceability platform, the SG MOBILE System ensures efficient speed-to-market decision-making anywhere in the world.”
The rapid shift from a pilot project to full-scale implementation in Santa Barbara County highlights the effectiveness of Sustainable Generation’s technology and the benefits of proactive collaboration. This project sets a benchmark for municipalities seeking innovative and environmentally responsible waste management solutions while efficiently tackling regulatory and operational challenges.