Anaerobic Digester Output Digestate Fiber-to-Energy
Intellergy’s patented revolutionary technology is the most efficient, cleanest and most cost effective way to turn sewage sludge (biosolids) into useable green energy without combustion or harmful residue going into landfill, water sources or the air. Every year the U.S. agriculture generates over 3 million dry metric tons of digestate fiber from agriculture anerobic digester (AD). Digestate management options include land application, landfill disposal, incineration, and composting. However, the options for using digestate are becoming more limited and face increasing challenges that may ultimately eliminate some of these land disposal options. For many agricultural facilities, the present practice also involves long distance hauling of digestate, requiring additional fuel and creating air pollution, including greenhouse gas emissions. At the same time, there is great need to expand renewable energy resources.
Intellergy has developed a technology that converts digestate fiber generated from AD treatment after dewatering to 50-60% moisture into high value “green” hydrogen, electricity and other renewable beneficial products utilizing its proven patented “Steam/CO2 Reforming” technology. The technology offers a number of unique advantages including the ability to process high water content feedstocks. The Intellergy system operates most efficiently with digestate fiber moisture content of 55% typically achieved by commercial dewatering screws to reduce the moisture content of the digestate to the preferred 55% prior to entering the non-combustive reforming phase of the process. This also achieves sterilized water for on-site use. Most other incineration or auto-thermal gasification technologies require the moisture content of feedstock to be below 10% prior to processing. Intellergy can provide a sustainable digestate management option to generate the greatest overall economic and environmental benefit, while having the most favorable life-cycle costs.
Another unique advantage of the Intellergy technology is that it is designed to be combustion-free. Since no combustion is involved in the reforming process, there are no significant air emissions issues, and greenhouse gas emissions are significantly reduced. This is a huge environmental benefit and is especially important in regions where there are strict air quality standards. Processing digestate fiber also fully avoids the potent release of CH4 (25 times worse than CO2) and N2O (298 times worse) from land disposal of digestate.
The Intellergy system has been designed and built to be modular and skid-mounted. The modular technology is highly scalable and can be deployed to process large volumes of biosolids, up to 600 dry tons per day (DTPD), or smaller quantities ranging down to 7 DTPD. The modular design allows the system to be easily expanded by the addition of more skids. The skids are fabricated and tested offsite before arriving at the treatment plant. The Intellergy equipment is compact, with a 25 DTPD (50 wet tons @ 50% solids) unit requiring only 6,000 square feet. This compact size makes it possible to install the system at almost any wastewater treatment plant.
The Intellergy process has been commercially demonstrated to convert organic materials into high-grade hydrogen (H2) gas, electricity (via fuel cells), and offers options using Intellergy’s patented Fischer Tropsch (FT) process to produce hydrocarbon liquid fuels (FT drop-in Diesel and FT Jet fuel). The patented technology offers a very viable solution to agricultural digesters facing limited options to manage their digestate.