Nitrogen back purging device for BOG compressor

Abstract

The invention discloses a nitrogen back purging device for a BOG compressor. The device comprises an air inlet pipe, a filter is installed on the air inlet pipe, the air inlet pipe is connected with one end of a first pipeline, the other end of the first pipeline is connected with a filter tank, the filter tank is connected with a dryer through a second pipeline, the dryer is connected with a nitrogen supercharger through a third pipeline, the nitrogen supercharger is connected with a gas storage tank through a fourth pipeline, the gas storage tank is connected with one end of a fifth pipeline, the other end of the fifth pipeline is communicated with the air inlet pipe, the communication part of the first pipeline and the air inlet pipe is arranged at the portion, close to the filter, of an air inlet , and the communication part of the fifth pipeline and the air inlet pipe is arranged at the portion, close to the filter, of an air outlet. The nitrogen back purging device has the advantages that the filter can be purged by nitrogen, a liquid net membrane gathered on the filter is quickly removed, an input end of the BOG compressor can be prevented from being blocked, it is ensured that the BOG compressor can be put into use in time, BOG is recycled in time, and the pressure of an LNG storage tank is effectively controlled.

Description

technical field [0001] The invention relates to the field of industrial compressors, in particular to a nitrogen back-purging device for BOG compressors. Background technique [0002] At present, a large amount of BOG gas with a high dew point will be produced during the unloading of LNG ships and equipment purging and replacement at the LNG receiving station, and the suction port of the BOG compressor is equipped with a 55-mesh conical filter. During the recovery of BOG, due to the temperature lower than Due to the dew point of part of the gas, it will accumulate a liquid mesh at the conical filter, resulting in a clogging effect, resulting in a decrease in the inlet pressure of the BOG compressor and unable to operate normally. This condition is especially obvious during the loading and unloading of LNG. When a liquid film appears on the inlet filter of the BOG compressor, the process operator is currently injecting nitrogen by connecting the nitrogen hose to the nitrogen...

AI Technical Summary

Problems solved by technology

Although this technical solution can solve the above-mentioned technical problems, there are still defects. The solution is to reversely purge the filter from the air outlet of the compressor, and the nitrogen gas will move backward from the compressor. It is equipped with a flow meter, so it is easy to cause damage to the flow meter when purging

On the other hand, part of the nitrogen remains in the compressor, and when it works again, it is easy to cause the compressor to start under pressure and affect the service life of the compressor

Images