20 BULLETIN 1010, U. S. DEPARTMENT OF AGRICULTURE. 



The cost of the material used and the oil lost in the bleaching 

 operation after treating the oil with caustic amounts to about 0.21 

 cent a pound of crude oil, of which approximately one half represents 

 the cost of the fuller's earth and the other half the value of the oil 

 lost in the operation. 



DEODORIZING. 



Deodorizing is an entirely mechanical operation and involves no 

 charge for chemicals. There is a small loss of oil in the entrain- 

 ment, which varies according to the local conditions, but even this 

 small quantity of oil is recovered by means of the grease trap in the 

 sewer. 



FUEL. 



The cost of fuel for caustic treatment and bleaching is compara- 

 tively low. For deodorization, however, the fuel charge is the main 

 item of cost. Not only must the oil itself be heated to over 400° F., 

 but it must be maintained at this temperature while approximately 

 25,000 pounds of steam are blown through it. Unless the steam has 

 been previously superheated, it is evident that its passage through 

 the oil will raise its temperature to that of the oil itself, which would 

 operate to lower the temperature of the oil. Therefore not only must 

 25,000 pounds of steam be generated but it must be superheated to 

 at least 450° F. before it can effectively serve its purpose. The oil 

 itself must likewise be raised to this temperature, all of which accounts 

 for the large quantity of fuel used. This consists not only of coal as 

 burned under plant boilers for steam but also of fuel oil used in the 

 direct-fired oil heater. 



LABOR. 



The labor necessary for handling the oil through the refinery is 

 quite evenly distributed among the three principal operations. It 

 is estimated that two men — one skilled workman and one unskilled 

 laborer — can operate the plant under the general direction of the 

 chemist and plant superintendent. A charge of $13.80 is made for 

 these two workmen for each of the three operations, or a total of 

 $41.40 for each batch of 25,000 pounds of oil. The cost of the techni- 

 cal supervision is charged to overhead by including the salaries of the 

 chemist and plant superintendent with those of the general executive 

 force and assuming that a tenth of their time will be devoted to 

 matters connected with the refinery. 



OVERHEAD. 



The overhead item covers all plant charges not enumerated in the 

 above, and consists of such costs as the following: Interest on a 

 $40,000 equipment, building charge, water, insurance, power, office 

 expenses, and selling charges. 



