Kjeldahl nitrogen and Kjeldahl analysis

Nitrogen is one of the main parameter for variety of samples; such as wastewater, water,fertilizers, foods, soil etc. Each fraction of nitrogen (Nitrate, nitrite, ammonia, TN, Total Kjeldahl Nitrogen) is very crucial and their limits are regulated. Amount the fraction of nitrogen fractions;  Kjeldahl Nitrogen is widely analyzed to get information regarding the sum of inorganic and organic nitrogen. One of the most well-known method for the analysis of  Kjeldahl Nitrogen consists of below steps;

-          Digestion with acid to decompose all organic nitrogen into ammonia
-          Distillation with base to convert ammonia to ammonium form
-          Detection step by titrimetry, ion selective electrode or colorimetry

Above method was developed by Johan Kjeldahl, Danish Scientist. It was accepted because, it was easier and requires very simple experimental apparatus.

There are official methods (EPA, EN, ISO, SM etc.) that follow above steps.
EFLAB  manufactures digestion and distillation units for the analysis of  Kjeldahl Nitrogen.
Kjeldahl Nitrogen Digestion Unit  
Kjeldahl Nitrogen Distillation Unit

Kjeldahl Nitrogen Digestion Unit

Complete stainless steel body, isolated to heat transfer
4,6,8,12,20 sample capacity options 
Electronic thermostat, programmable temperature up to 450 oC
One piece gas vent located over digestion tubes
Digitally controlled digestion temperature
Logging digestion temperature
100,300, 800 ml of digestion tubes options

Kjeldahl Nitrogen Distillation Unit
Controlled by microprocessor
LCD based touchscreen
Automated warning system
100, 300 and 800 ml of test tubes options
Warning system for water level at vapor generator
Settable distillation time from 0 to 200 minutes
Addition of base volume is settable
Plexiglas front design
1600 Vapor generator
3L/min water consumption