BROMINE FROM SEA WATER STEWART 167 



chambers and out through the suction fans. Soda ash solution is 

 circulated continuously in each chamber. This is done by pumping 

 it from a tank at the bottom and spraying it in at the top through 

 36 nozzles, from which it falls by gravity and drains again into the 

 tank. 



At proper intervals the strong bromide-bromate solution formed in 

 the absorption chamber adjacent to the blowing-out tower is pumped 

 to a storage tank. The charges of partially brominated soda ash 

 liquor in the other members of the series are then pumped forward, 

 in turn, to the next tank nearer the one which has just been emptied 

 to storage. When the tank farthest from the blowing-out tower has 

 been emptied, it is charged with a fresh solution of soda ash. Plate 

 4, figure 2, shows the south end of the bromine extraction plant. 

 Plate 5, figure 1, is a view looking down on the absorption liquor 

 tanks, and plate 5, figure 2, shows the battery of pumps which circu- 

 late the soda ash solution. The inlet flume may be seen overhead. 



After the bromine from the sea water has been collected in the 

 form of a solution of sodium bromide and bromate, the remainder of 

 the process is performed according to methods which have been pre- 

 viously in use in the industry. The bromide-bromate liquor is treated 

 with sulfuric acid to liberate the bromine. The free bromine vapors 

 are then steamed out of the acidified solution and are condensed into 

 pure liquid bromine. Plate 6, figure 1, shows the plant in which the 

 bromine is finally obtained in liquid form. The two bromide-bromate 

 liquor storage tanks are seen at the side of the building and the hori- 

 zontal sulfuric acid storage tanks are in front of it. 



The bromine is used in the manufacture of ethylene dibromide, 

 which is also made in the building shown in plate 6, figure 1. Ethyl- 

 ene is made by passing ethyl alcohol vapor over heated kaolin cata- 

 lyst to form ethylene gas, which is in turn brominated according to 

 the standard method to form pure ethylene dibromide. Plate 6, fig- 

 ure 2, shows the ethylene plant and powerhouse, which are both in 

 the same building. The battery of valves for controlling the ethylene 

 production is shown in plate 7, figure 1. A consignment of finished 

 product on the shipping platform of the ethylene dibromide plant is 

 shown in plate 7, figure 2. 



The powerhouse emploj^s hand-fired boilers and makes steam only 

 for heating and evaporating purposes. Its capacity is about 15,000 

 pounds of steam per hour at a pressure of 150 pounds per square inch. 

 Operating electric power is purchased from the Tidewater Power Co. 

 It is delivered to the plant at 33,000 volts, where it is stepped down 

 to 2,300 volts in two transformer banks. 



The entire plant is functioning as anticipated and is removing 

 about 15,000 pounds of bromine per day from sea water. This is 



