Water in Dairy Plants – The Application
In dairies water is used for direct processing of products, as well as for steam generation, for heating, cooling, and cleaning purposes. Therefore, continuous monitoring of dairy waste water faces the measurement technique with significant challenges.
Dairy waste water is characterized by high concentrations of proteins and fats. Thus, by a high content of carbons. Annex 3 of the German Waste Water Ordinance defines the requirements for the influent of water from the dairy industry, stipulating the chemical oxygen demand (COD) as a monitoring parameter.
Due to the application, high concentrations of 20,000 mg/l and even high peak loads of up to 40,000 mg/l can occur. Usually, these raw samples are characterized by a high content of solids (particle, flakes, etc.). However, these samples must be supplied to the analyser without clogging. It is important that the sample will be supplied in its original state and without any filtration. Only then the sample is treated as a whole and the real concentration can be detected. The process control of the measurement system itself must be free of any memory effects and blockages. Moreover, it must have a high reproducibility.
LAR’s QuickCOD/TOC analysers work with the ultra high temperature combustion method at 1,200 °C. This high temperature guarantees the complete oxidation of the sample. The robotic, horizontally and vertically moving needle injects a defined sample amount through a patented injection modul into the reactor. There, all compounds will be fully oxidised. Due to this intelligent sample transportation system, particles and solids in the sample do not disturb the measurement. They are rather treated as an important part of the sample and will be detected completely.