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Sum parameter – Total Organic Carbon




                                        TN b – total bound nitrogen

                   SCA-130-503


            Although nitrogen compounds are  essential          ■ Total nitrogen TN b
            for nature and the environment, high nitrogen       The variety of possible nitrogen compounds
            depositions  can lead to problems. Nitrogen         necessitated the definition of a sum
            compounds enter the  environment primarily          parameter that represents the total nitrogen
            through agricultural processes.  Nitrogen-          compounds. For this purpose, the so-called
            containing  fertilizers constitute the largest      TN b (total bound nitrogen) was defined and
            proportion. But nitrogen compounds can also         standardized.
            enter the environment via chemical industrial
            processes.                                          The TN b is the total nitrogen content of  a
                                                                sample in the form of ammonium, nitrite,
            Excessively high concentrations of nitrogen         nitrate, as well as organic compounds. The
            compounds in the environment can cause              TN b does not include dissolved or  gaseous
            eutrophication of water bodies. Eutrophication      nitrogen (N 2). A differentiation between
            is the process of uninhibited growth of algae       inorganic and organic nitrogen compounds is,
            and other organisms due to an excess supply         by definition, not possible.
            of nutrients. This overgrowth results in a lack
            of oxygen in the water, which can lead to fish
            mortality and to the formation of aquatic dead
            zones.

            Bound nitrogen occurs in nearly  all waters,
            mostly in the form of ammonia, nitrate, nitrite
            or organic compounds.






                                                                ■ Determination according EN 12260
                                                                EN 12260 describes the determination of
                                                                nitrogen in the form of free ammonia,
                                                                ammonium, nitrite, nitrate and organic
                                                                compounds that can be converted under the
                                                                described oxidative conditions.
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