Then {HEAD ~ the coating solution} is sprayed on {TAIL ~ the surfaces} and the reactor is drained of the excess solution in such a way that the solution can be sent to a recovery system, if desired 
Then { HEAD ~ the coating solution } is sprayed on { TAIL ~ the surfaces } and the reactor is drained of the excess solution in such a way that the solution can be sent to a recovery system , if desired
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL 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