Request Information

Gol Sewage Treatment Plant

Wednesday, April 22, 2020

Gol municipality chooses energy-smart wastewater treatment
Biowater Technology CFIC® is selected for secondary treatment for Gol municipaility’s refurbishment project. Together with a number of other energy saving measures, may make the completed plant the most energy-efficient in Norway. 

Natural beauty: Just south of Gol Treatment Plant there are large recreational areas, including camping and fly fishing


Like many other municipalities handling domestic wastewater, Gol municipality has to meet new and stricter requirements for discharges from treatment plants. In order to accommodate these, it has been decided to completely rehabilitate Gol treatment sweage treatmet plant, with clear goals of sustainability and energy savings. In addition to sewage, the treatment plant receives a considerable amount of wastewater from the local Nortura slaughterhouse.

- We want our municipality to grow, and in order to facilitate growth, we must invest in good environmental measures for the future.

We have a strong focus on sustainability and minimal energy consumption. That is why we have gone for what we consider to be the most forward-looking solution, where the bioreactor in particular is most exciting.

Elin Tangen, Head of Water and Wastewater Gol Municipality.

  Elin Tangen



Unique biological step

In order to fulfill the new requirements, few muncipalities in Norway until now have gone beyond introducing a biological treatment stage at their plants. Perhaps the most exciting thing about Gol's plant is the use of a new type of Norwegian-developed bioreactor solution, which uses far less energy during operation than traditional solutions do. This is the patented CFIC® process from Tønsberg-based Biowater Technology AS , a biological process that uses less than half the energy of ordinary MBBR solutions.

Malmberg AS who, together with Biowater Technology, have signed a contract with Gol municipality for turnkey refurbishment of the treatment plant. The plant will be expanded to secondary treatment for 9,500 person equivalents. 

Gol 3D
Compact and efficient: Model of the new Gol Treatment Plant. Illustration: Biowater Technology AS


Within two years

The plant at Gol can thus be regarded as a giant leap in the use of advanced biofilm technology over traditional solutions.


- The energy saving will last throughout the life of the plant, and sets CFIC® as the new benchmark for Norwegian municipal wastewater treatment,

Ilya Mario Savva, CEO Biowater Technology AS.


The contract includes process and mechanical engineering installations and has a contract sum of NOK 32 million. Malmberg is a contractor with a 50/50 contract for sub-delivery with Biowater Technology. The contract will be completed within a 2-year period. Consultant for the municipality is Norconsult.

This is an important project for us at Malmberg to become a leading environmental technology company in Norway. Gol Municipality's ambitions fit very well with Malmberg's mission of clean energy and clean water for a better environment.

This is a good foundation for good cooperation in the years to come.

Sofia Knudsen, Business Unit Director Malmberg AS.

  Sofia Knudsen


A major energy item in Norwegian wastewater treatment plants is ventilation. Ventilation in wastewater treatment plants uses large volumes of air over long periods, especially in process halls, and usually has a low degree of heat recovery. All this means a lot of energy for both fan operation and for heating fresh air.

Existing ventilation systems must therefore be replaced and replaced by new. New plant will be adapted to new process, but the sysems will be maintained as it is today for clean areas. This provides better ground ventilation in the building and reduces the odors from returns.

New ventilation for point extraction from all closed process units and odor reduction systems is included. The point suction system is cleaned via Photox (UV) odour reduction and activated charcoal. Total treated air volume in process halls will be approx. 3 350 m3 / h, of which 1000 m3 / h is from biological purification stage, lower than conventional MBBR through the use of CFIC®. Specified airflow and average temperature difference of 13 K create a heating requirement of 25 kW. Heat recovery will be installed within parts of the process hall ventilation system.