Kemira Nutrients Recovery System – An Efficient Method of Eliminating Air Pollution in NPK Fertilizer Plants

In the 1980's Kemira has realized an extensive program aiming at air pollution control at its compound fertilizer plants. The reasons for undertaking such a program were on one hand the sharp increase in the output of the fertilizer plants and the subsequent increase in the emissions in the air. On the other hand, the company wished to get prepared for the new air pollution control legislation that was to take force in the country. The company has also invested in research and development by means of which information has been acquired on the formation of emissions in the fertilizer process and the methods of reducing them. The results of this work has been successfully combined with the long experience in the operation of fertilizer plants. As a result, Kemira has developed a nutrients recovery process for fertilizer plants with which the valuable nutrients in the waste gases can be returned to the production process in a concentrated form. This method prevents the formation of waste waters harmgful to the watercourses, in addition to which it allows the utilization of external nutrients-containing waters as make-up water of the scrubbing waters without extra costs. The system is in use at all of Kemira's fertilizer plants.