VARO Specialmaskiner A/S

Customised Evaporation for Industrial Wastewater

Bjørnkjær has great success producing customised evaporators for companies with wastewater and waste heat that can be reused and delivered at low temperature.
This solution is for customers having problem with disposal of wastewater after water treatment
mechanically/chemically. Many customers are having problems meeting the demands for discharge. By
investing in an evaporator more advantages can be obtained.
Total separation of the wastewater means that the distillate can be reused as treated water, that the
amount of concentrate can be used as raw material or that the amount of concentrate is being reduced.
This means the expenses for depositing are minimised, and at the same time “free energy” is delivered. In total this gives an impressive green profile.
  • Utilisation of waste heat
  • Reuse of raw material
  • Minimised deposit
As regard to the economy it is not bad either. Dependent on the temperature, heat amount and actual
price of water, environmental treatment, chemicals etc., calculations show a very attractive return on
Not only waste heat but also district heating is suitable for reuse – e.g. 80-95°C heat can after evaporation be delivered at 65-75°C. Water at this temperature is suitable for space heating or other purposes.
Please contact us for a non-committal estimate on your possibilities for evaporation.

See the following actual cases:

Danfoss, Nordborg, Denmark
ELTS 1500
Capacity of 1500 l/h
This plant treats oil emulsion from the metal working industry.
The feeding water has a content of oil of 5-10%.
Through a 2 step evaporator the liquid is being reduced, resulting in a content of oil of 90-95%, which is high enough for being used as fuel. The 2 steps consist of one natural circulation evaporator and one flash evaporator.
The heat for working the plant comes from Danfoss’ power station with 140°C hot water. This is used for
evaporating the liquid inside the evaporator. The water from the central heating is used for cooling in the condenser. This means the plant delivers 75°C hot water for space heating on site.

NSR, Helsingborg, Sweden
ELTS 500
This plant is a two step vacuum evaporator with a capacity of 500 l/h. The company treats oil-bearing wastewater for various customers. The plant concentrates oil-bearing wastewater from approx. 8% to 90%. The heat for working this plant comes from district heating – approx. 70°C. A CIP programme is integrated in the plant in order to automate as much as possible.