Bilge pump

Abstract: A sensor system for sensing liquid level in a bilge, for use in automatic bilge pump actuation. First and second field effect sensors are potted or sealed within a container or the bilge wall and are aligned in a vertical array and each comprise a substantially planar pattern of “electrodes” or conductive traces disposed on a printed circuit board (PCB) along with integrated circuits used to create a loop or arc-shaped electric field. As bilge liquid rises to the proximity or level of the field effect sensors, a change in the arc-shaped electric field is sensed and, in response, a bilge pump is automatically actuated to pump liquid out of the bilge. Optionally, the pump control can be programmed by use of a microprocessor to permit control of on-off timing and prevent undesirable effects of “sloshing.”

Abstract: An optical bilge pump apparatus has two optical fibers with gaps cut therein and associated light transmitters-receivers. The apparatus is responsive to high and low liquid levels in the pump such that the pump is turned on when both gaps in the optical fibers are submersed in liquid, and the pump is turned off when both gaps in the optical fibers are not submersed in liquid.

Abstract: An apparatus for removing oil or the like from water, which is contaminated with oil or the like, particularly from ship bilges, which comprises a bilge pump controlled by a float switch. An air separator and an oil separator are provided. A pump member pumps water contaminated with oil via the air separator through the oil separator. The oil separator includes at least one collecting tank for the removed oil. At least one coarse and at least one fine separator of foam are arranged. The coarse separator is connected with the collecting tank which includes a shutoff member. An insert is provided within the coarse separator and separates an inlet from an outlet, as well as has at least one flow channel extending obliquely upwardly, seen in the direction of flow.

Abstract: Vessel movements are considered the primary anthropogenic pathway for the secondary spread of marine non-indigenous species. In comparison to the well-studied mechanisms of hull fouling and ballast water, the importance of bilge water for domestic and cross-regional spread of non-indigenous species is largely unknown and has the potential to compromise the overall effectiveness of biosecurity management actions. In this study, the diversity and abundance of biological material contained in bilge water from 30 small vessels (<20 m) was assessed using traditional and molecular identification tools (metabarcoding of the 18S rRNA gene). Laboratory-based studies were also used to investigate the relationship between voyage duration and propagule success. A large taxonomic diversity in organisms was detected, with 118 and 45 distinct taxa identified through molecular and morphological analyses, respectively. Molecular techniques identified five species recognised as non-indigenous to the study region in 23 of the 30 bilge water samples analysed. Larvae and fragments passed through an experimental bilge pump system relatively unharmed. Time spent in the bilge sump was found to affect discharge success, particularly of short-lived and sensitive larvae, but survival for 3 days was observed. Our findings show that bilge water discharges are likely to pose a non-negligible biosecurity threat and that further research to identify high-risk vessel operating profiles and potential mitigation measures are warranted.