Volume 2

Survey of the river Tees.

  • Great Britain. Water Pollution Research Board.
Date:
1931-1937
Catalogue details

Licence: Public Domain Mark

Credit: Survey of the river Tees. Source: Wellcome Collection.

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    TABLE 114—Treatment of Effiuent from Coke Oven Gas Coolers by Spraying at Various Temperatures Temperature of effluent ; Time taken by trout to overturn in | per cent. before spraying solution of sprayed effluent Pes: Hours Minutes 40 1 21 50 21 0 60 Non-toxic A test of the process on a large scale was then carried out at the Newport Ironworks, where facilities were provided by the courtesy of Messrs. Dorman Long & Co., Ltd. The flow of coke oven effluent through one of the naphthalene settling tanks was stopped and the effluent in this tank was heated by steam. A small rotary pump was used to spray the heated effluent through an atomiser of the type used in the direct cooling towers of the ammonia recovery plant. The degree of atomisation achieved by this means appeared to be considerably less than that produced by the laboratory apparatus used in the experiments reported in Table 114. The reduction in the toxicity of the effluent brought about by spraying at different temperatures is shown in Table 115. The original concentration of cyanide varied from 2-2 to 3-0 gm. (CN) per 100,000 ml. TABLE 115—Results of Large Scale Test of Treatment of Effiuent from Coke Oven Gas Coolers by Spraying Temperature of effluent Time taken by trout to overturn in a 1 per cent. before spraying solution of sprayed effluent Gs Min. 23 7 28 16 35 15 41 14 47 ica 17 50 40 53 48 58°5 pee hye It was, for various reasons, found impossible, during the period of the survey, to apply any of the methods of reducing the quantity of cyanide entering the Estuary. There was thus no opportunity of observing the effects of the methods suggested in reducing the toxicity of the Estuary waters and so in reducing the mortality of smolts. REFERENCES @) SouTHGATE, B. A. Gas World, 1933, 98, Coking Sect., 49. ®) Trans. Instn Gas Engrs, 1926-1934. (3) Jones, W. J. J. chem. Soc., 1914, 105, 1560.