Abstract: Conservation of oily liquid sealant in coaxial odor trap cartridges for waterless urinals is accomplished in the present invention by the addition of a liquid-flow-diverting structure having at least one helical fin encircling the outer surface of the cylindrical partition that extends downwardly from the cartridge top cap. In a preferred embodiment two similar diametrically-opposed helical fins conserve sealant by modifying the otherwise vertical downward flow path to a downward incline that minimizes down-the-drain sealant loss by intensifying recovery of stray traces of sealant that become detached from the main layer of sealant and get swept along with the downward flow of wastewater in the outer chamber during a usage event. The sealant recovery action of the helical fins that takes place in the outer chamber is further enhanced by specially proportioning the cross-sectional flow area of the three chambers in the cartridge to maximize the cross-sectional flow area of the outer chamber.

Abstract: A waterless urinal meeting U.S. sanitation code requirements and providing advantages of cost savings, water conservation and easy maintenance is particularly beneficial in public or institutional urinal facilities. An odor trap cartridge unit is configured as a coaxial dual chamber bell trap that eliminates the need for conventional P or J type traps required in water-flushed urinals. In the odor trap, a body of oily liquid sealant, floating on a body of trapped residual urine, serves as an odor barrier but allows entering urine to immediately permeate downwardly through the sealant and proceed to a drain without requiring flushing. The odor trap is molded from two plastic parts that are assembled together to form a cartridge unit that fits readily into a receptacle cavity of urinal bowl configured for wall mounting. The cartridge stays in place by friction and gravity, and can be easily removed with a special tool.