2019-02-15 09:20Bloggpost

CleanFlow deliver unique filtration technology to Spanish pulp mill

The Swedish innovation company CleanFlow AB has developed a unique method for cleansing green liquor. Good for the economy, environment and quality. Now, the company has received its fourth big order. This summer, the company’s system will be delivered to a sulphate pulp mill in Spain.  

“We are very happy that our technology is continuously being implemented around the world”, says CEO Lennart Källén. 

The first mill in the world to use CleanFlow’s green liquor filtration was Swedish. Thereafter, a pulp mill in Japan followed, and then one in South Africa. And now it is Spain’s turn. The mill in Pontevedra in Western Spain belongs to the forest industry group Ence Energia y Cellulosa S.A., which produces more than 450 000 tonnes of eucalyptus pulp annually. 

Kidney of the pulp mill 

CleanFlow’s cleansing method is based on microfiltration. This process has proven itself to be very successful. “The filter is like the pulp mill’s kidney”, Lennart Källén explains.  

“The liquor becomes completely free of foreign particles, which allows the production to increase, and the energy and chemical consumption to decrease. A medium-sized mill can save up to SEK five million in chemicals every year.”  

Contributes to a fossil-free society 

CleanFlow is a member of the Paper Province cluster that works for sustainable development, with a focus on forest bioeconomy. Maria Hollander, CEO of Paper Province, is happy that yet another pulp mill has discovered CleanFlow’s technology.  

“It contributes towards making the mills even more sustainable. They save energy, are able to use fewer chemicals during the process, and it also allows for an increase in the production of paper pulp. Resource efficiency is the key to becoming a fossil-free society”, she says. 

Delivered fully assembled  

The new system is fully manufactured, complete with instrumentation and electrical equipment, in workshops in Forshaga. After a test run, it will be delivered to the mill in May.  

“The capacity has been dimensioned to suit the Spanish mill. Because it has been built in modules, it can be expanded and adapted for future increases in production”, says Lennart Källén. 

The deal was made together with CleanFlow’s partner Sotgar Systems, and the contract sum amounts to SEK 15 million. 



CleanFlow was established in 2009 and developed a new cleansing technology for the pulp industry. The patented cleansing method was based on microfiltration and was developed in collaboration with the university KTH Royal institute of Technology.  

A pilot plant was started at Munksjö Aspa Bruk AB in 2010, and the process development continued there until 2013. After positive runs at the pilot plant, Munksjö Aspa Bruk AB became the first mill in the world to have a commercial CleanFlow system in 2013.  

This was followed by another delivery to Japan in 2016, as well as a system delivery to South Africa in 2017.  

The benefits of CleanFlow’s technology can be summarised as follows 

  • Particle-free processed liquor  
  • Continuous process 
  • Very cost-effective with capacity increases 
  • Low operation costs 
  • Easy to adapt to existing systems 
  • Large capacity in a small space 
  • Modular concept 

CleanFlow AB is a privatly owned limited company with its headquarters in Forshaga in Sweden, where the founders and Girincubator AB hold the shares.  


Per Olofsson, Chairman of the Board, tel. +46 (0)73 311 80 82 

Lennart Källén, CEO, tel. +46 070 693 76 90 

Lennart Börjeson, Project Manager, tel. +46 (0)70 380 28 93 

CleanFlow AB
Framgårdsvägen 14 
667 31 Forshaga, Sweden

Om Paper Province

Paper Province is a world-leading business cluster within the forest bio-economy. We are owned and operated by more than 100 member companies. The cluster is based in Karlstad, Sweden, and mainly operates in the province of Värmland and the surrounding area, but also nationally and globally. Together with our member companies we work towards sustainable development with focus on innovation, skilled work force, internationalization and regional mobilization.