Industrial Applications of Pulsed Particle Beams and Pulsed Power Technologies, страница 3

Figure 7 shows the circuit diagram of the inductive energy storage (IES) pulsed-power generator. A static induction thyristor (SI-Thyristor) is used as the main switch. The principle of the operation is as follows. First, the storage capacitor (C_d) is initially charged by DC voltage supply (E). When the field effect transistor (FET) is turned on, C_d discharges through L, SI-Thyristor and FET. Additionally, the inductive energy is stored on L. The capacitance of C_d is large enough so that its voltage does not change very much during this discharge. Second, when the current in L reaches a certain value, FET is turned off, interrupting the cathode current of SI-Thyristor. As a result, the current is forced to flow through the gate of SI-Thyristor and the diode (D). This current quickly draws the carriers out of the SI-Thyristor. Finally, in the absence of carriers, the SI-Thyristor turns off abruptly, inducing a high voltage on L. The induced voltage is further multiplied by the transformer, resulting in the breakdown in a discharge reactor of coaxial cylinder configuration.

Figure 8 shows experimental results of NO and NO₂ removal in nitrogen atmosphere at E=90 V, the inductive stored energy (W_L) of 4.7 mJ/shot, and the initial NO and NO₂ concentration of 200 ppm. In Figure 8, the vertical axis shows the NO ant NO2 removal rates (ε). It is seen from Figure 8 that the NO and NO₂ removal rates increase with increasing repetition rate, approaching 100 % at the repetition rate of 750 and 1250 Hz, respectively [18]. Such results are considered to be due to a large amount of nitrogen radicals produced.

CONCLUSIONS

From these experimental results, we have obtained the following conclusions:

·  The Si nanosized powders, which have been successfully synthesized by the IBE method, indicate blue-light emission. The photoluminescence is very stable, even left for four months after the synthesis.

·  Using the PWD method, Ni-Fe-O nanosized powders are prepared to evaporate Ni and Fe wires in O₂ ambient pressure. Sintered Ni-Fe-O nanosized powders exhibit sharp resistivity changes at the T ranging from 203 to 285 ^°C.

·  The treatment of NO_x gas was carried out by irradiating IREB, and 70 % of NO_x is removed by firing 10 shots of IREB. Additionally, the removal efficiency of NO_x is estimated to be 20–100 g/kWh.

·  The experiments of NO_x gas treatment was also carried out by using inductive-energy-storage (IES) pulsed power generator. As a result, NO and NO₂ removal rate increases with increasing repetition rate.