(Contribution from WilliaTi ?» Glapp Laboratories, Inc.) 



'""T^n? USE OF CTTL(".R]'y..TION AND HEAT 

 ■ - IN THE COl-TROL OF FAraCNE BORERS. 



by Albert P. "Richards 



A venr definite problem has existed for some time in regard to the ac- 

 tivities of marine orfranisms, both the so-called foulin" organisms and 

 marine borers, in more or less confined areas contaim nc;' sea vrater. 

 These environments take such forms as sea water intake tunnels of metal 

 or concrete, storage tanks, the interior of drydock pontoons, etc. The 

 attachment of quantities of orr^anisms to the walls of sea vrater conduits 

 in -^any locations results in considerable economic loss due to the re- 

 duction of flow of water, especially where the water capacitv is needed' 

 for efficient- plant operation. In the case of one power-freneratin^ 

 station on the North Atlantic seaboard, havj.ng a concrete condenser cool- 

 ±nz water intake tunnel approximately 7 feet square and 2^0 feet long, 

 33i tons of mussels, liytilus e dulis , were removed, havin? accumiilated 

 from June to November" of one year. Naturally the volume of these or- 

 p^anisms reduced the effective cross section of the tunnel to a point 

 where the flovf of coolin^ vrater was not sufficient to meet the require- 

 ments. It is also interestinp; to note that the conditions in the tunnel 

 \Tere such that abnormal {^roiTth rates of Fytilus edulis were recorded. 

 Studies made at the time of annual cleanrn?Ts~at this site indicated a 

 rate of Piro^fth of at least 1000 tons per acre per ypsr, while the best 

 yeild from crop farms for this organism under favorable conditions are 

 of the order of 10 tons per acre per year. Similar conditions having 

 been encountered at many locations, it is losrical that a considerable 

 amount of research has been carrj ed out in an effort to develop methods 

 of control. Two such methods which show considerable promise in this 

 field involve (l) the chlorination of the sea water, and (2) the use of 

 elevated temperature. A number of commercial installations using one or 

 the other of these mef^ods are now in operation. Due to the fact that 

 in numerous instances analogous situations exist in which marine borers 

 are encountered, it was only natural f^at during the course of the above 

 mentioned v/ork the reactions of the boring organisms to heat and chlorine 

 were also studied. 



It must be remembered that the actual values mentioned in the following 

 discussions must be regarded, not as absolute quantities, but rather in 

 a general way since the species covered specific location of the test, 

 etc., all exert a considerable influence on the results obtained. Actu- 

 ally, ar^r close limits must be determined under the expected conditions 

 of service. The vrork is still in progress and much remains to be learned. 



A large proportion of the laboratory studies was carried out at the In- 

 ternational Nicket Company marine exposure laboratory at ''Tri'^htsville 

 Beach, North Carolina through the courtesj^ and cooperation of Vr, LaOue 

 and Mr. H. T. Paterson of that company, and Iir. R. 3. Ifertin of the 

 Vfellace ""c Tiernan Products Inc. who supplied much apparatus and valuable 

 Yielp. 



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