Studies on Ultrafine Particle-Removal Inside a Wet Cyclone

The electrospray is one of the most well-known spray techniques using highly concentrated free charges from high intensity electrical potential between two oppositely charged electrodes to produce very fine and highly charged water droplets in a conical shape (i.e., Taylor cone). We propose the application of this spray technology to a wet cyclone system to maximize particle collection efficiency. Highly charged droplets impact fine particles inside a flue gas, stick to the collector body, and fall through the cyclone cone in a gravitational direction. We have designed and fabricated an electrospray-driven wet cyclone electrostatic precipitator, investigating particle collection performance with a tangential velocity of ~10 m/s at the cyclone inlet, applying various voltages and water supply flow-rates. Experimental results show that the effective driving voltage for reaching the PM2.5 collection efficiency over 95 % is 35 kV. Comparing performances of previously commercialized wet scrubbers, in terms of the same treatment capacity, we obtained 70 % power and 75 % water consumption savings, respectively