Analytical device for determining a digestion parameter of a liquid sample

An analytical device for determining a parameter of a liquid sample, including a digestion parameter, such as chemical oxygen demand, total carbon content or total nitrogen content, comprising:

• a reactor system including a digestion chamber for ascertaining the parameter of a liquid sample and a measuring transducer disposed on opposing sides of the digestion chamber along a measuring path that extends through the digestion chamber, the measuring transducer configured to register a measured parameter correlated with a measured value of the liquid sample mixed with one or more reagents in the digestion chamber;
• a container system including a plurality of containers for storing samples, reagents and waste products;
• and
• a transport and dosing system for metering and transporting the liquid sample and reagents from said containers into a metering container and for disposal of waste products from said metering container into a waste container, wherein the metering container includes a plurality of light barriers adjacent said metering container and configured for limit level determination of different metering volumes within the metering container,
• wherein:
• said transport and dosing system includes the metering container, a piston pump and a sample taking apparatus comprising a peristaltic pump at least for removal from a sample taking location of a predetermined volume of a liquid as the liquid sample;
• the sample taking location is connected with said metering container by a liquid transport line;
• the peristaltic pump is disposed between the sample taking location and the metering container and is embodied to transport the liquid sample from said sample taking location through said liquid transport line into said metering container;
• and
• the metering container is further connected with the digestion chamber via the piston pump.