The Orange County Transportation Authority (OCTA) operates a fleet of 232 low-emission liquefied natural gas (LNG) transit buses. To allow the safe maintenance of these vehicles in an indoor environment, additional facility ventilation must be installed to ensure methane gas does not accumulate in any concentration that could potentially consitute an explosive hazard. To ensure safe maintenance operations, OCTA embarked upon a maintenance facility upgrade program at the Anaheim maintenance facility.
44300.00
OCTA installed an LNG venting system in each bus maintenance bay at their Anaheim facility. When pressure in the bus LNG tanks increases above nominal levels, the bus mechanic hooks the vent system up to the bus vent connection. The facility vent system consists of a stainless steel pipe manifold with quick-connect couplers located in each bus maintenance bay. Vented methane gas is routed through the pipe manifold into a single vent line that penetrates the facility roof and safely vents the methane to the atmosphere.
The objective of this project was to install an LNG Vent System to facilitate the safe maintenance of OCTA's fleet of LNG buses indoors. The LNG Vent System ensures that natural (methane)gas vented from the bus tanks cannot accumulate inside the maintenance facility, creating a potentially dangerous condition.
This project is fully implemented. No additional issues have been reported by OCTA, and the vent system continues to work as designed.
The OCTA Anaheim facility vent system is fully operational. One issue was uncovered during initial installation; the quick-disconnect located in each bus bay as a compressed natural gas disconnect and not rated for the extremely low temperatures assocated with liquefied natural gas vapors. The installation contractor replaced the quick disconnect couplers with the proper components at no additional cost to OCTA.