Development of a Greywater Recycling System for Galley-Scullery Wastewater

Navy vessels, such as littoral combat ships (LCS), operating in littoral waters are subject to local and federal regulations with respect to disposing of wastewater. These strict regulations prohibit discharging of greywater in many areas, therefore the greywater generated by the galley, scullery, and other shipboard operations must be stored aboard the ship until it can be safely offloaded shore side or at sea outside of littoral water limits. LCS holding tanks are normally designed to only support a 12 hour period of operation, and retrofitting a larger tank is expensive. To avoid the frequent, expensive visits to offload waste ashore, Mainstream Engineering proposes building upon a greywater recycling system that was originally developed for recycling Army kitchen wastewater. This system has a small footprint, uses minimal power, and is not prone to irreversible fouling. In Phase I, Mainstream will redesign the pretreatment section of the greywater recycling process to handle the Navys galley and scullery waste stream. A continuous bench-scale system will then be tested and optimized. A 50 gal/hr modular prototype will also be designed. During Phase II, Mainstream will focus on prototype optimization, life testing, and commercialization of the product.