Principle of Multi-Pollutants Removal Technology in Flue Gas by Ozone - Simultaneous Multi-Pollutants Removal in Flue Gas by Ozone - page 40

generator equipped with a combination of the glow discharge and silent discharges.
In 2003, Ahn et al . [44] reported the ozone generation characteristics by duplicating
the surface and corona discharges. Their results had a maximum ozone yield of
247 g/(kWh), which is two times that with a single discharge.
Song et al . [45] conducted multi-discharge experiments in an ozone generator
with two discharge spaces and three electrode structures, as shown in Fig. 2.7(a).
In these experiments, the central electrode was grounded. With a 180° phase
difference, two high AC voltages were imposed on the inner and outer electrodes,
respectively. Consequently, the ozone concentration and production rate reached
as high as 17185 ppm and 783 g/(kWh), respectively. In light of the arc discharge
limitations in the discharge power and size, Shimosaki et al . [46] and Kaneda et
al.

[47]

studied effects of the dielectric material and trigger electrode configuration
(Fig. 2.7(b)) on the ozone yield assisted by mixed discharges. Results showed that
covering partly the dielectrics could increase the ozone concentration and
production rate. A maximum ozone production rate of 115 g/(kWh) appeared
under the circumstances with four trigger electrodes used.

(a) (b)

Fig. 2.7 Schematics of mixed discharges (Unit: mm)

2.3.5 Pulsed Discharge

Among various discharge types, pulsed discharge is very favorable for plasma
chemical reactions. This discharge type has been widely used in the
desulfurization and denitrification fields and has already achieved good
performance. A nanosecond pulse can generate a pulse power, whose pulsed
discharge can be used to efficiently produce ozone. Advantages of pulsed