The emission requirement from the authorities has been tightened dramatically in the last 10 years.This means that we at Jernforsen also provide equipment for flue gas cleaning for our plants. This is done through three different technologies in order to meet our customers' financial needs and the regulatory requirements.
This technology consists of a mechanical separation in which the coarsest particles are separated. By using the centrifugal force that is generated in each small cyclone, the particles are hurled against the wall and thus separated from the flue gas. The efficiency is high, but separating the finest particles is extremely difficult since the weight of each particle is too small to be separated from the flue gas. The operating cost is extremely low since the cyclone is completely mechanical apart from the dust lock under the cyclone. Depending on the type of fuel we can treat dust levels down to 150 mg / Nm 3.
Plants placed near urban areas demand an additional purification step in addition to the multi-cyclone in most cases. The gases are led into a large chamber and by reducing the velocity as well as charging the fine particles electrically with negative voltage from the electrodes; a movement is created towards the positive pole, which consists of the discharge electrodes. The dust particles are thus stuck on the electrodes, which are cleaned through the process of a hammer hitting the electrodes causing the particles to fall to the bottom of the electrostatic filter for further transportation to the ash container. Our electrostatic filters have high separation efficiency, high operational availability and good service spaces. They are best used where the dust requirements are between 10-150 mg / Nm3.
In collaboration with several leading suppliers of fluegas condensation, we can offer an integrated solution for those situations when this technology is appropriate. In this process the remaining energy in the fluegas is used. It is passed through a scrubber, which is used to both recover the energy in the fluegas and as a washer to reduce the level of particles. The energy is transferred via a heat exchanger to other systems while the dust is separated from the water through water treatment. Depending on the conditions, the heat recovery can be about 25% of the boiler capacity and the dust emission down to about 30 mg / Nm3.