The eductor efficiency equals: 



Amount of water delivered by a 5 -inch in ft^ 



5-inch nozzle delivery in ft^ + 5.5-inch eductor in ft^ 



950 



950 + 1,142 



= 45.5 percent 



This percentage is high compared with data taken from hydraulic books. 

 However, in these particular conditions of operation, there is usually a 

 certain amount of sluicing or siphoning effect helping, the eductor. The 

 main function of the eductor is to force the suspended material through 

 the pipe at a high enough velocity to keep the material in suspension. 

 The percentage of sand in suspension in water by volume through a sluice 

 pipe equals: 



ft^/sand/min 



Giant delivery per minute in ft^ + 2.5-inch flume pipe delivery per minute 



^ 10.58 X 27 ^ 280J. ^ 20.3 percent 

 1,142 + 238 1,380 ^ 



The percentage of sand suspension by volume through the eductor equals: 



ft^/min 



Giant volume per minute in ft^ + eductor volume per minute in ft^ 



= 10.38 X 27 = 280.3 = 13^4 percent 

 1,142 + 950 2,092 



To determine the total plant efficiency, the operation of the three units 

 must be combined. The efficiency is equal to: 



ft^ sand moved per day 



Total volume of water used ft^/day 



= 45,000 ydVday X 7,148 gal/ft ^ X 27 ftVyd^ ^ ^5 4 percent 

 41,000 gal/min X 1,440 min/day 



The total amount of sand moved during the operations from March 1947 through 

 January 1948 was 8,168,905 cubic yards; best results were recorded during 

 December. It is impractical to convert these figures to plant efficiency 

 over this period, as the total number of plant operating hours is not known, 

 and the general operating conditions have varied extremely during this 

 period, as shown by the photographs (see Figures). Both the water lines 

 and the sand lines have been elongated considerably. In the discharge line, 

 it has been necessary to add a booster station to deliver the suspended 

 material to the desired locations. This booster station was located at a 



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