Automatic nitrogen determination instrument for the determination of total nitrogen in solid waste

In view of the fact that there is no standard method to determine total nitrogen in solid wastes at present, it refers to the relevant standard methods for determining total nitrogen in soils and domestic and foreign municipal solid wastes. The municipal sewage treatment plant sludge, urban municipal waste rot, and pharmaceutical plant sewage are selected. Solid Waste Residues of Sludge and Hydrocortisone Mycelium, Bases of Pesticide Plants - Alkaline Flocculated Sludge and Biochemical Sludge of Wastewater Treatment Plants, and Seven Soil Nitrogen for Testing Specimens and Standards of KDN-08C Automatic Determination of Nitrogen After the sample came out, the relatively high total nitrogen content was measured. The medium and low samples were used as test samples. Kjeldahl method, reagent spectrophotometry and acid titration method were used to modify the total nitrogen determination method for solid wastes. The results of the study showed that there is no significant difference between the two methods, which is applicable to the determination of total nitrogen in solid wastes.

Weigh 1.40g of the mixed catalyst (2.2.2) to the nearest 0.01g, add it to the bottom of the digestion tube (2.1.3) by drying the long-necked funnel, and heat it in an electric furnace. The digestion temperature is controlled at 360-410°C, and the solution is micro-boiling and sulfuric acid. The condensate is preferably about 1/3 from the bottom of the digestion tube. KDN-08C automatic nitrogen determination instrument is too high temperature, easily lead to ammonium decomposition of heat, nitrogen loss; KDN-08C temperature is too low, easily lead to organic decomposition is not complete. After the sample is digested to gray-green, the sample is dissolved and clarified, and digestion is continued for at least 2 hours so that the ammonium salt reacts completely. However, after digestion, the digestion solution should not be dried, and cooling is performed until distillation.

KDN-08C automatic distillation device before distillation, first check the distillation device for leaks, and an empty decoction tube by adding a small amount of deionized water, by automatic liquid or manual dosing, add about 28mL35% NaOH, in the absorption Approximately 30 mL of a 2% boric acid absorbing solution was added to the bottle to start the Kjeldahl nitrogen determination apparatus. Steam distillation was used to wash the pipe with the distillate.

Through the above analysis and determination, it can be seen that the KDN-08C automatic nitrogen determination method has a very good advantage in the determination of nitrogen content in solid wastes. At the same time, the relationship between nitrogen content and the environment and changes can be known through analysis. The results of the instrument determination are consistent with those of other methods. It is more convenient to perform the operation and save time. The volume of the blank distillate should be the same as the volume of the sample distillate.