Boil-off gas incinerator with dilution air blown across a combustion products stream

摘要

A boil-off gas incinerator for an LNG carrier or ship has at the upper end of its combustion section 82 a plenum chamber 98 or the like for pressurised dilution air, a proportion DPof the dilution air being blown across the combustion section 82 via nozzles 102 in the form of radial jets that penetrate the stream of combustion products C and break it up into a turbulent mixture M. The nozzles 102 can be offset from each other at different distances along the stream. A proportion DQof the dilution air is directed downwards in an outer annular passage 88 and then turned into an inner annular passage 90. The proportion Drmay be approximately 55%. The stream of combustion products C may contain hot spots, but the mixture M is below the boil-off gas auto-ignition temperature (TA, fig 7) and does not contain mixing devices.