This may be achieved by pre drying {HEAD ~ means}, such as {TAIL ~ a pump} to provide a stream of air after switch off of the engine, which air may be heated by residual heat from the catalyst or engine 
such as
This may be achieved by pre drying { HEAD ~ means } , such as { TAIL ~ a pump } to provide a stream of air after switch off of the engine , which air may be heated by residual heat from the catalyst or engine
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH