This system, which integrates the company's proven technology with specialised process flow conditioning, is in use at several dairy farms around the U.S. As part of a multi-stage separation approach, it has been shown to condition feedstocks for higher yield gas production and lower OpEx.
Biogas results from decomposition of organic matter in anaerobic conditions. This organic matter comes from various sources, including farm animal waste products such as manure. Spiral Water's products effectively filter this wastewater stream and also concentrate solids, which can then be converted to fertiliser and sold.
Placed before an anaerobic digester, the new spiral water system also conditions and optimises volatile Total Suspended Solids (TSS) and Volatile Suspended Solids (VSS) by breaking down deformable solids and making for a more nutrient-rich feedstock liquor that then goes through the specifically selected micron screens to the digester. Depending on the feedstock, with this system the anaerobic digesters are expected to create 10-30 percent more methane in the same footprint in a shorter digestion cycle time.
In addition, because the filters clean mechanically, they also remove non-digestibles from the wastewater stream. By keeping digester tanks cleaner, the filters also help to reduce OpEx.
"Spiral Water systems have proven to be a key component in small and midsized anerobic digestion systems. By effectively removing inorganic non-digestible solids and homogenising digestible solids, we increase gas production as well as reduce operating costs wasted on removing non-digestible solids from the gas digester. The result is a cleaner, more productive anerobic digester system," said Gerard J. Lynch, CEO of Spiral Water.
Other benefits include less retention time; no chemicals; lower energy requirements; less maintenance and labor costs than with traditional systems; less CapEx and OpEx than using centrifuges; and the potential for a smaller digester footprint in a newly constructed system.