An electrostatic precipitator comprising (i) a housing having a central chamber , an inlet region comprising a flow inlet and an outlet region comprising a flow outlet , the housing being constructed and arranged to receive a gaseous flow in a gaseous flow direction between the flow inlet and the flow outlet ;and a plurality of screens , characterized in that (ii) the plurality of screens is secured in pairs, with at least two pairs within the central chamber, each pair comprises a set of electrically chargeable first screens and a set of electrically grounded second screens wherein each set of electrically chargeable first screens comprises at least one secured screen, wherein (a) each set of electrically chargeable first screens of the pair is constructed and arranged to be provided in operation with an identical electrical charge selected from one of a positive charge and a negative charge; and (b) each set of electrically chargeable first screens of the pair is provided with a plurality of spikes constructed and arranged to protrude into the gaseous flow in a direction substantially opposed to the gaseous flow direction; and each set of electrically grounded second screens of the pair comprises at least one secured screen, wherein all the screens are constructed and arranged to be electrically grounded in operation; and that (iii) at least one screen-cleaning means is operatively connected to each set of electrically chargeable first screens and each set of electrically grounded second screens . (i) a housing having a central chamber , an inlet region comprising a flow inlet and an outlet region comprising a flow outlet , the housing being constructed and arranged to receive a gaseous flow in a gaseous flow direction between the flow inlet and the flow outlet ;and a plurality of screens , characterized in that (ii) the plurality of screens is secured in pairs, with at least two pairs within the central chamber, each pair comprises a set of electrically chargeable first screens and a set of electrically grounded second screens wherein each set of electrically chargeable first screens comprises at least one secured screen, wherein (a) each set of electrically chargeable first screens of the pair is constructed and arranged to be provided in operation with an identical electrical charge selected from one of a positive charge and a negative charge; and (b) each set of electrically chargeable first screens of the pair is provided with a plurality of spikes constructed and arranged to protrude into the gaseous flow in a direction substantially opposed to the gaseous flow direction; and each set of electrically grounded second screens of the pair comprises at least one secured screen, wherein all the screens are constructed and arranged to be electrically grounded in operation; and that (a) each set of electrically chargeable first screens of the pair is constructed and arranged to be provided in operation with an identical electrical charge selected from one of a positive charge and a negative charge; and (b) each set of electrically chargeable first screens of the pair is provided with a plurality of spikes constructed and arranged to protrude into the gaseous flow in a direction substantially opposed to the gaseous flow direction; (iii) at least one screen-cleaning means is operatively connected to each set of electrically chargeable first screens and each set of electrically grounded second screens . <EOS>