Device and method for extracorporeal blood treatment

A device for extracorporeal blood treatment, the device comprising:

• a balancing system including at least two balancing chambers;
• a first pressure sensor arranged at an inlet of each of the at least two balance chambers and a second pressure sensor arranged at an outlet of each of the at least two balance chambers, the first pressure sensor and the second pressure sensor configured to determine a fluid pressure at their position;
• a first temperature sensor and a second temperature sensor at inputs of the at least two balance chambers, the first temperature sensor and the second temperature sensor being arranged to determine a temperature in the inlet and the outlet of each of the at least two balance chambers;
• and
• a calculation device for calculating an ultrafiltration volume using a pressure difference established based on fluid pressure values determined by the first pressure sensor and the second pressure sensor, and a temperature difference based on temperature values determined by the first temperature sensor and the second temperature sensor,
• the calculation device arranged to calculate the ultrafiltration volume as a volume withdrawal based on the pressure difference and the temperature difference at the inlet and the outlet of each of the at least two balance chambers of the balancing system,
• wherein the calculation of the volume withdrawal is carried out based on the following formula:
• UFD=a*ΔP*DFF+b*ΔT*DFF,
• wherein UFD is the ultrafiltration volume, ΔP is the pressure difference, ΔT is the temperature difference, a and b are coefficients, and DFF is a dialysis liquid volume.