In addition to being ideally suited for processing wastewater solids at wastewater treatment plants (WWTPs), G5S can process a wide variety of residuals: including food waste and animal manures by themselves or in combination with sewage sludge. Residuals are managed where they are collected and do not require transportation for disposal, land application, landfill cover or composting, but rather become G5S feedstock that is transformed into 100% usable and valuable products: clean water, renewable energy and a sterile ash which can be used as a building material or further processed for other beneficial uses.

WWTPs will avoid trucking costs, tipping fees and landfill disposal costs because sludge processing takes place onsite and so is no need to produce or haul biosolids away for disposal or beneficial use. The G5S alleviates controversy over the fate of biosolids in the environment and human health effects due to biosolids contact because the G5S’s combustion stage operates at temperatures exceeding 2,200°F thereby destroying all compounds of concern, preventing their reentry to and recontamination of the environment.

Gate 5 System Description
Primary G5S components are shown above however, the flexibility inherent in the G5S design means that G5S components can be configured to complement existing and desired processes at the WWTP or other facility using the G5S. “Raw” feedstock such as primary sludge will be mechanically dewatered and stored in a feedstock bin, a live bottom silo and an auger system delivers feedstock to a proprietary, circular, flash/ring dryer having no moving parts (making it superior to traditionally used sludge dryers). The dryer dehydrates and pulverizes the feedstock into a powdered biofuel which is fed to a conventional burner-boiler combustion system to both power a turbine, producing sustainable electric power and reheating the circulating (drying) gas for the dryer. Distilled water is a byproduct of the drying process while heat and ash are products of the combustion. The air emissions control system uses BACT (best available control technology) comprised of a baghouse, wet scrubber and selective catalytic reduction (SCR) to control metal, dioxin/furan and organic toxic air contaminants (TAC) and can meet California’s strictest air quality emissions criteria as mandated by California’s South Coast Air Quality Management District.

Gate 5 System Benefits

The proprietary G5S, along with offering WWTP owners significantly lower OPEX in comparison to digestion-based solids management practices, has a number of significant benefits compared to conventional: sludge / biosolids / animal waste / and food waste treatment practices, specifically:

- - - Complete conversion of dewatered organic solids to 100% usable products (sustainable electricity, heat, distilled water, and usable sterile ash) without fossil fuel or grid electricity

- - - The G5S is up to 85% efficient in the conversion of dewatered sludge to usable energy and is capable of producing electricity in excess of the parasitic load requirements of the G5S for use at the WWTP or elsewhere.

- - - Near real-time ability to harvest latent energy in and eliminate sewage sludge, reducing necessary digester volume, residence time, and storage facilities along with a commensurate reduction in generated odors. There is no need for the lengthy AD process to produce biosolids (40 CFR Part 503) or biogas and no products and nothing from a G5S needs to be land managed. This means that some or all AD facilities can be decommissioned, providing substantial cost savings to the WWTP’s budget.

- - - Onsite destruction of sewage sludge in a G5S means elimination of biosolids transportation, tipping fees, spreading costs and related disposal costs. The associated environmental impacts of hauling / transportation emissions AND remnants of Residuals in the environment are also eliminated.

- - - The G5S combustion of Residuals (a non-hazardous secondary fuel) is determined by USEPA to not be incineration (40 CFR Part 241) as it burns powdered biofuel at very high temperatures (>2,200°F) providing a “best practices” process for destruction of emerging contaminants of concern including: pharmaceuticals, PFAS, pesticide residuals, endocrine products, PFC’s, other POP’s, micro / nano-plastic materials and prevents same from migrating back into the air, water or soil.

- - - A WWTP using a G5S avoids image controversy and regulatory / legal uncertainty because no biosolids are produced, meaning nothing is land applied and therefore there is no potential impact to human health or the environment. Complete and economical destruction of sewage sludge (raw, processed or biosolids) will remove an agency’s concerns about future changes to biosolids regulations, monitoring requirements and their cost implications.

- - - The G5S is the ideal partner as a renewable energy generator because the G5S can be operated 24/7 and during the times when renewable power cannot be produced from solar and wind. The G5S is highly scalable and can be powered solely only on biosolids with as little as 5 WTPD (wet tons per day) (dewatered to 20% solids) or at large sites because all subsystems are very scalable.

- - - Data indicates up to 50% more energy can be recovered in a G5S than current solids handling processes traditionally employed at WWTPs.

- - - The G5S processes Residuals at costs approaching 50% of traditional anaerobic digestion and offsite land-based sludge management-based solids management systems.