Abstract: An electrostatic precipitator having a plurality of electrostatic precipitation units positioned within the electrostatic precipitator. Each of the electrostatic precipitation units includes a plurality of negative wire electrodes and a plurality of positive electrode plates. The electrostatic precipitation units are arranged such that spacing between the negative wire electrodes of a first electrostatic precipitation unit is a first distance apart, and spacing between the negative wire electrodes of additional electrostatic precipitation units is less than the spacing between the negative wire electrodes of the first electrostatic precipitation unit. Moreover, a variable voltage is applied to the each of the electrostatic precipitation units between the positive electrode plates and the negative wire electrodes so as to cause particles in the exhaust gas to adhere to the positive electrode plates.

Abstract: A radiation protector treating method including the steps of pulverizing a used radiation protector to obtain a pulverized radiation protector material and mixing the pulverized radiation protector material with boron powder and bismuth powder, and casting the pulverized radiation protector material mixed with the powders into an electric melting furnace and also casting silicon powder, lead oxide powder and carbon powder into the electric melting furnace. Radioactive contamination is prevented by using a radiation attenuating and absorbing material for each of various radioactive substances attached to the radiation protector.