Customer case:

Process monitoring – An easy way to save costs

Oct 5, 2020

Valmet Total Solids Measurement (Valmet TS) helps WWTP Kaiserslautern, Germany, to save approximately 44 000€ in heating costs and increase its solid content in the digester by around 1% within one year. A controlled primary sludge removal ensures the process stability in the digestion and thus achieves savings due to longer residence times that means higher gas amount and higher gas quality. By switching off the primary sludge removal step in a controlled manner, significantly less water should enter the digestion process.


Location Kaiserslautern, Germany
WWTP details

Approx. 17 million m³/a of wastewater to treat

Extension size 240 000 PE

Connected approx. 180 000 PE

Digested sludge development – approx. 9800 m³/a Agriculture: thermal 50:50

Solution Valmet Total Solids Measurement (Valmet TS)
  • The solid content in the digester rose by around 1% within one year
  • Increased gas flow
  • improved gas quality
  • Savings in heating costs
  • Stable processes also for the following dewatering systems
Keywords Valmet TS, Wastewater, Automation, Europe, Germany


Evaluation Electricity  Heat
Gas production

50300 m³

Red. Wärmebedarf +SF

380 MWh/a
Energy content of digester gas

32200 kWh

Savings Nov.-April

400 MWh/a
Power generation

13200 kWh

Add. Heat CHP Nov.-April

130 MWh/a
Electricity cost savings

24 400 €

Heating oil equivalent

66800 L/a
(Electricity purchase price-operating costs CHP) Heat cost savings 43 900 €
Values rounded(lower heating oil purchase - CHP remuneration)

Data and images were provided by Stadtentwässerung Kaiserslautern AöR.
Stadtentwässerung Kaiserslautern AöR did the calculation with support from WVE GmbH Kaiserslautern.