171 



TABLK 21 



COMPARISON OF ORICINAL AND EXTRACTED OILS' FROM SMALL TEST PIECES 



AFTER EXPOSURE IN SEA WATER 



Test Test Test Test 



Original piece piece piece piece 



oil No. IL No. 2L No. 3L No. 4L 



Time Exposed 222 days 475 days 512 days 787 days 



Loss 11.6% 17.5% 18.1%, 21.9% 



Specific Gravity 1 .059 1 .063 1 .067 1 .066 1 .067 



Tar Acids .... '. 10.7%o 5.7% 3.8% 3.6% 3.6%o 



Disiillalioii: 



Up to 210° C. 1.5%o 0.0% 0.0% 0.0%o 0.0%o 



210-230° C 9.5% 2.6% 1.6% 1.7% 1.2% 



230-250°C 16.5%;\ ,,„^ /l0.3% 11.0% 7.8% 



250-270°C 12.6%„/ '^' \l3.9%o 13.9% 14.1% 



270-290°C 8.1%o 15.9%, 12.0% 11.5%o 10.7% 



290-315° C 8.2%, 14.5% 10.6% 12.0% 12.2% 



315-355°C 16.4% 17.8%, 17.6% 16.3% 19.6% 



Residue 27. 2%^ 31.2% 33.5%, 33.1% 34.2% 



*The oils from the ditTercnt layers of these test pieces were analyzed separately, but only the 

 average analysis for each block is given, since the differences in composition between layers were small. 

 There was, however, a slightly smaller amount of low boiling constituents and tar acids in the outer 

 layers. 



total oil is greater in the air. Analysis of oils extracted from piling shows simihir differ- 

 ences in air anri water sections. A typical analysis of this kind is given in talile 22 

 for a pile pulled from tlu' Alameda Wharf of the Associated Oil Comiiany after four 

 years' service. 



TABLE 22 



COMPARISON OF OILS EXTRACTED FROM AIR, WATER, AND MUD .SECTIONS OF A 



PILE AFTER FOUR YEARS' SERVICE 



Original* Air Water Mud 



Oil Section Section Section 



Per Cent of Oil in Treated 



Wood 49.9 54.1 55.0 



Specific Gravity 1.06+ 1.078 1.074 1.072 



Tar Acids 3.6%o 3.0% 1.1% 



Distillalion. 



Up to 210° C... 0.0% 0.0%, 0.0% 0.0%o 



210-235° C 5.5% 1.1% 1.8%o l-8%o 



235-270° C 23.5% 16.4% 21.5%, 21.9% 



270-315° C 23.1% 26.5% 25.7% 25.9% 



315-355° C 19. 3%o 24.3%, 21.8%o 21. 3%o 



Residue above 355° C. 28. 0%^, 31.4% 28.8%c. 28.8% 



'Manufacturer's Analysis. 



The above results further emphasize the \alidity of our former conclusions that 

 the low Ijoiling fractions should he limited to the amount necessary for good pene- 

 tration and that the tar acid specification should refer to the fractions above 235° C. 



