This section will deal with the operation, troubleshooting, and repairing of the submerged tube and the flash type distilling plants that are used by the Navy. The major differences between the three types are the kinds of energy used to operate the units and the pressure under which distillation takes place.
Heat recovery distilling units use diesel engine jacket water instead of steam as the heat source.
Vapor compression units boil the feedwater at a pressure slightly above atmospheric pressure. Low-pressure steam and heat recovery units depend on a relatively high vacuum for operation. Since the vapor compression type found on surface crafts is being replaced with the heat recovery distilling units, vapor compression distilling units will not be covered in this manual. Enginemen usually share responsibility with Machinist s Mates for the maintenance and operation of the low-pressure steam distilling plants. The three major types of low-pressure steam distilling units are submerged tube, flash type, and vertical basket.