Formerly
- Kemira Oy
- Kemiar GrowHow Oyj

2004 - Hydro Norsk demerge the fertilizer business (Hydro Agri) to form Yara International ASA
2007 - Yara acquires 30% of Kemira GrowHow Oyj from state of Finland.  Offer tendered for remaining shares

Previous: 600,000 MTPA
Present: 800,000 MTPA (Total)

1968-1969 - Construction of roaster and sulphuric acid plant
1981-1982 - Expansion of sulphuric acid plant
2007 - Expansion of sulphuric acid plant

SWECO AB - Acid Plant Expansion
Yara (formerly Kemira GrowHow) Siilinjärvi site in Finland increased the production of sulphuric acid which is used as one of the raw materials for fertilizer production at the site. The project included a new liquid sulphur burning plant with storage systems for liquid sulphur, which was invested by Fortum, and the modifications of two existing sulphuric acid plants of Yara.
Sweco prepared pre-engineering and cost estimate of the project. After the investment decision had taken place, Sweco was assigned as the EPCM contractor of the implementation phase. The assignment included project management, procurement and all design engineering disciplines: process, layout and piping (3D modelling), structures, buildings, electrification, instrumentation, automation and HVAC. The existing plant was laser scanned for the preparation of the 3D model of modifications. We carried out also the risk analyses of the project and assisted in installation supervision and start-up of the processes.
Part of the waste heat produced in the processes is used for district heating of the nearby Siilinjärvi town. The heat recovery systems were also included in Sweco’s scope and were based on our process simulations and optimization calculations of the heat recovery system.