Stuart's Oil, Grease, and Dirt .Extraelor is shown in Fig. 7. It has for its object the removal from the exhaust steam (before it reaches either the condenser, pumps, or boilers) of all oil. grease, or grit, by the action of surface plates placed in the exhaust pipe, and also by draining the valve chests and steam casings into the oil cylinder. by suitable connections.
Tests of Steam Separators.—A test of the efficiency of steam separators of six different kinds was made in 1801, by Prof. R. C. Carpenter, at Cornell University. Each separator was subjected to the same conditions. Steam was furnished by a 60-horse-power boiler. From the separator it was led to a 20-horse-power engine, which was belted direct to a Buffalo blower. Thus a constant load was placed upon the engine, insuring a uniform velocity cf steam through the system. The quality of the steam before entering and leaving the separator was determined by means of a calorimeter. In order to obtain a wider range of quality than that furnished by the boiler, a vertical section of the steam pipe was enclosed with a or cylinder. This drum had several openings along the side to permit water being introduced at various heights, and an outlet was arranged at the bottom, thus maintaining a good circu lation. The steam was tints partially condensed and
charged with water. The qualities of the steam before and after passing the separator, which have the best result, and the efficiency of separation, which is the ratio of per cent. of water removed to per cent, of water in the entering steam, are given in the following table : Each separator reached a maximum efficiency at about 35 per cent. of moisture. No marked decrease in pressure was shown by any of the separators, the most being 1.7 to .6 lbs.
The investigation shows that although changed direction, reduced velocity, and perhaps centrifugal force are necessary for good separation, still some means must be provided to lead the water out of the current of the steam. If such provision is not made, momentary separation may occur, but before the water can drop or run from any surfaces in the direct current, it will be again taken up by the rapidly moving steam which continually surrounds it. The high efficiency obtained was probably largely due to means having been provided for leading away the water after separation.
Settler : see Mills, Silver.