Anaerobic Digestion

Zero Waste Energy offers a high-solids, batch processing anaerobic digestion design  for facilities starting as low as 5,000 TPY and up to 90,000 TPY of almost any organic material utilizing SMARTFERM proprietary technology.  The batch processing  is well suited for the production of biogas from stacked solid organic waste in a non-continuous  process. Unlike other dry fermentation technologies, SMARTFERM offers a sub-grade percolate tank, which significantly reduces percolate and biogas process piping runs as well as the size of motors and fans to move them. The sub-grade percolate tank also greatly enhances the overall thermal efficiency of the process. The SMARTFERM design allows for a thermophilic mode of operation and is offered on two platforms: a shop fabricated steel digester system or as a cast-in-place concrete digester system.

All SMARTFERM systems can be designed to include biogas-processing technology for combined heat and power (CHP) generation for both onsite use and export as well as compressed natural gas (CNG) for use to fuel waste transport vehicles. In addition, in-vessel composting (IVC) options can provide partial or complete sanitizing of compost for the wholesale or retail market.

SMARTFERM is offered on two platforms based on the amount of organic waste to be processed: shop fabricated steel digesters or as a cast-in-place concrete digesters (see below for details). Our technology is built in the US specifically for the waste industry.

SMARTFERM Plug Flow Dry AD Technology

Zero Waste Energy offers a high solids system for facilities larger than 15,000 tons per year  for almost any organic material utilizing Thöni’s plug flow high solids anaerobic digestion technology for biogas production.

Based on its 25 years of experience and specialist knowledge, Thöni’s plug flow digester is ideal for dry organic waste, even if it contains a high level of impurities. Key components, such as the accessible, heated, digester floor and the robust and powerful paddle-shaft, are proven and patented. This SMARTFERM plug flow process is characterized by high performance, low operating costs and ease of maintenance.

The core of the Thöni process is the unique plug flow digester capable of treating relatively dry, high-solids, material. A slowly rotating paddle-shaft ensures the optimal mixing of the digestion substrate, ensuring a high biogas yield. Heating elements, through which hot water flows, heat up the substrate. A piston pump transports the digestion residue from the digester via a system of pipes to the next treatment step. Part of the digestion residue is returned to the digester as inoculum, enriching the fresh input material with a defined quantity and quality of micro-organisms.

This SMARTFERM system provides the ability to scale very well for higher facility throughputs to over 100,000 tons per year.  The unique process features offered make for an ideal solution for the production of renewable natural gas for the local collection fleet or pipeline injection.