Lignin sulfonate pollution

Natural groundwater and creek water is known to exhibit blue emissions owing to the presence of fluorescent humic and fulvic acids. Lignin sulfonate pollution manifests itself in an increase in the fluorescence of waste water. In many cases its strong enough to be of use in the continuous fluorimetric sensing of pollutants. Lakshman [14] analyzed a number of soil and run-off samples for the nature and stability of the intrinsic fluorescence. A strong correla-... 

Marathon-Howard process. A treatment of waste sulfite liquor from sulfite pulp manufacture to recover chemicals and reduce stream pollution. The waste sulfite is treated with lime and precipitates (1) calcium sulfite for use in preparing fresh cooking acid for the sulfite pulp process and (2) a basic calcium salt of lignin sulfonic acid (lignin sulfonates) that can be pressed and used as a fuel or used as raw material for vanillin, lignin plastics, and other chemicals. The remaining liquor with its BOD reduced 80% is the effluent. 

Direct fluorescence measurement has been used to determine the approximate level of lignin sulfonate in natural waters polluted by paper mill waste. In this case, the choice of excitation and emission wavelengths is made to minimize interference from naturally occurring fluorescent compounds, such as humic acids (119,120). 

Thruston, A. D., Jr., Fluorometric method for the determination of lignin sulfonates in natural waters,/. Water Pollut. Contr. Fed., 1970,42,1551-1555. 

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