Air Pollution Control Systems from Dürr that use the separation process function by separating the pollutants from the exhaust air using the mechanical properties of the substances.
This means that neither chemicals nor thermal oxidation are used to remove the pollutants from the exhaust air. The decisive factors in the separation process are the speed and inertia of the components and the size of the particles.
Particle size is a key consideration in the case of the Ecopure® CCF system for example, which removes the dust from exhaust air before it undergoes a catalytic exhaust air treatment. It is important to choose a filter with pores that are smaller than the dust particles that need to be separated out. This ensures that the dust particles cannot pass through the filter. In this case, the separation process is based on the size of the pollutant particles.
By contrast, the systems in the Ecopure® PAS product range separate pollutants out on the basis of their properties. The exhaust air volume flow is accelerated to such a high speed that the particles are removed as a result of their inertia. The exhaust air comes into contact with a washing liquid, which is generally water. The significant difference in speed between the gas and the liquid gives rise to shear forces. They break the film of liquid down into tiny droplets, which results in a larger surface area and allows the substances to be transferred more efficiently. Inertia and diffusion cause the pollutants to become bound to the water droplets and this allows them to be removed from the exhaust air.