Demonstration of Advanced Sludge Separation Treatment Technologies for Decarbonization of Wastewater Treatment Plants

This project aims to implement and demonstrate three innovative biosolids management technologies at Linda County Water District Wastewater Treatment Plant (Linda WWTP) in Olivehurst, California. This project focuses on optimizing biosolids management processes, intensifying solids thickening, developing alternative methods for resource recovery from the biosolids, and simultaneously reducing energy consumption and greenhouse gas (GHG) emissions from WWTPs. The project will also investigate the management of different conventional sludge streams, including primary solids and waste activated sludge, as well as solids streams emerging from advanced primary treatment processes.

The innovative technologies being demonstrated include two biosolids thickening technologies, Suspended Air Flotation Thickener (SAF) (Komline-Heron) and Biosolids Filtration Thickener (BFT) (Aqua-Aerobics), as well as one biosolids destruction technology, Ultra Energy Efficient Super Critical Water Oxidation (Ultra-SCWO) (Beyond The Dome Inc.). A Volute Thickener (Process Wastewater Technologies) is included as a conventional baseline technology for comparison. The performance of these technologies will be evaluated against conventional biosolids management processes, including rotary drum thickening and anaerobic digestion. Evaluation metrics include, but are not limited to, biosolids thickening efficiency, chemical consumption, filtrate/centrate quality, overall biosolids handling process management, biosolids destruction efficiency, energy efficiency (consumption and recovery), and operation and maintenance (O&M) requirements. This evaluation will help determine the capability of these emerging technologies to effectively manage a wide range of biosolids feedstocks with varying characteristics.

To support a comprehensive assessment, the project includes laboratory analysis of key parameters such as COD, nutrients (nitrogen- and phosphorus-related parameters), solids concentration, thickening efficiency, energy content, chemical usage (coagulants, polymers, surfactants), energy consumption, footprint requirements, performance reliability, ease of operation and maintenance, Measurement and Verification (M&V), and GHG emission monitoring. As the project lead, Caliskaner Water Technologies, Inc. (CWT) is collaborating with technology providers, utilities, and subject matter experts to advance the Technology Readiness Level (TRL) of these innovative and emerging biosolids management solutions and facilitate their broader adoption by utilities with unique bottlenecks.

Targeted benefits

As the demonstration progresses, the project team aims to achieve and validate the following benefits:

• Achieve significant energy savings of approximately 45–80% and enable energy-neutral to energy-positive plant operation through advanced biosolids thickening and Ultra-SCWO technologies

• Reduce GHG emissions from biosolids management processes by at least 35–40%

• Reduce operational expenditure (OpEx) of biosolids management processes by at least 15 to 20%

• Reduce footprint requirement of biosolids management processes by at least 60 to 70%

The project team also plans to conduct a wide range of technology transfer and outreach activities, including hosting technical tours, workshops and seminars, and giving conference presentations in collaboration with organizations such as the Water Research Foundation (WRF), the Water Environment Federation (WEF), the California Water Environment Association (CWEA), and the University of California, Davis. These efforts will help disseminate the project findings and bridge knowledge gaps related to advanced wastewater treatment technologies across the industry.