CYCLONES, VENTURI, SCRUBBERS
INTRODUCTION
For completing the installation of our wet electrostatic precipitators, but also for specific applications, we propose Cyclones, jet venture and scrubber (spray or with plates).
CYCLONES
It is a technology used for the abatement of powders with specific weight exceeding 300 kg/m3 and with fairly coarse particles (over 10 uM) and present in the air in concentrations high enough (more than 1 g/m3). The cyclones may have efficiencies of abatement between 85 and 95%. Among the most significant advantages of cyclones, we highlight the low pressure drop, the exemption from maintenance costs, low cost for installation and operation.
SCRUBBER
For the capture of coarse particles, present in the gaseous flows, we exploit technologies that have drops of liquid in motion relatively to the gas. The principle is based on the inertial impact and interception, but also the incorporation of the particles into the drops and wetting avoids the possibility of re-suspension and the condensation of the vapor over saturated present in hot gases.
Inside the spray scrubber, liquid droplets produced by sprayers descend by gravity through the gas that rises in a tower, up to be collected on the bottom. The capture efficiency increases with decreasing of the droplet size, it is therefore important to correctly select the atomizer to be used to produce the spray. Our scrubber may be equipped with a droplet inertial separator on the of the tower, which prevents the entrainment of droplets finer with the dedusted gas. The spray can be distributed both on the horizontal section that in several stages arranged at different heights of the tower. The washing water stored in the tank below the scrubber is recirculated through the centrifugal pump on the tower head. A purge keeps limited the concentration of pollutants in the water.
JET VENTURI
The Jet venturi of our conception are reliable device designed to treat large volumes of gas without the use of diaphragms or moving parts.
The washing fluid (water) is placed in a concave cone through the use of one or more spray nozzles, creating a current that sucks up the gases and vapors in the stream, in which the polluting particles are continuously absorbed and removed. The mechanism exploits the flow of gas and liquid through a convergent - divergent duct. The gas is saturated with water vapor in the convergent section, where the pressure is gradually reduced. In the divergent zone, in which the pressure increases, is the condensation of water vapor on the dust. This phenomenon increases the particles mass and facilitates its capture. The washing water stored in the tank below the jet venturi is recirculated through the centrifugal pump to the head of the equipment. A purge keeps limited the concentration of pollutants in the water.
The Jet Venturi designed by Fidia Engineering require minimal maintenance because there are no moving parts and operating speeds are reduced.
The efficiency of a Jet Venturi varies with a number of factors such as the temperature, the liquid-gas ratio, the concentration of the contaminants and the working pressures. With water pressure equal to 80 psig, can be achieved an efficiency reduction equal to 90%, for all particles larger than 5 microns. When the Jet Venturi is coupled with a wet electrostatic precipitator, it exercises the prior double function of cooling the smoke and break down the larger particles, for this reason usually the jJet Venturi works in lower water flows and pressures, ensuring low energy costs and allowing the removal of particles larger than 20 microns.