Abstract: The invention relates to a method for making the drying finely divided materials, more effective in a suction drier provided with a fine porous suction surface, where the radii of the fine pores of the suction surface are essentially within the range of 0.5-2 micrometers, and in which method, of a slurry containing liquid and solids there is made a filter cake (2,12,22) onto a fine porous liquid suction surface constituting the filter surface of the filter medium (1,11,21), According to the invention, the filter cake (2,12,22) and an oscillator (6,15,25) are arranged, in relation to each other, so that in between the filter cake (2,12,22) and the oscillator (6,15,25), there is generated an acoustic field by virtue of a mechanical contact between the filter cake (2,12,22) and the oscillator (6,15,25) or a structural element (7,16,26) connected to the oscillator.

Abstract: The invention relates to a filter medium particularly for filtering in a suction drier. According to the invention, the filter medium is manufactured of a material that can be made to oscillate essentially at a standard frequency.

Abstract: The invention relates to a method for cleaning the filter medium in a suction dryer by means of ultrasound in an essentially continuous operation. According to the invention, the ultrasonic beams emitted from at least one ultrasonic oscillator (1, 12, 22, 36) are focused essentially near to the filter surface (4, 14, 25) of the filter medium, advantageously on the filter surface (4, 14, 25) of the filter medium, in order to create at least one ultrasound focusing zone.

Abstract: An apparatus for detaching a filter cake created by a suction dryer from off the filter surface of a filter medium and for an essentially simultaneous treatment of the cake to a form advantageous for further processing. The apparatus comprises a suction dryer (1, 11, 27), a connected filter surface (4, 14, 28) and a basin (2, 13, 27) for the material to be filtered. According to the invention, in the vicinity of the filter surface (4, 14, 28) of the filter medium, there is installed a blowing member (7, 17, 21) with at least one part, the blowing effect whereof can advantageously be extended over the whole width of the filter surface (4, 14, 28) of the filter medium, on which surface the filter cake can be formed.

Abstract: Method in a suction dryer (10), which comprises a basin (12) for a suspension to be suction-dried, in connection with which basin one or several filter-plate discs (14a) revolve, onto whose faces a filtrate cake is gathered and dewatered by the effect of a suction flow passing through the filter plates (14a), the said filtrate cake/cakes being scraped or otherwise detached from the faces of the filter plates (14a). For the purpose of cleaning the porous structure and faces of the filter plates (14a), an ultrasonic detector or detectors (30) are provided in connection with the basin (12) for the suspension to be filtered, to which detectors an electric power of ultrasonic frequency is fed from an ultrasonic generator (32). For the time of the cleaning intensified by ultrasound, the suspension basin (12) is filled with a connecting and cleaning liquid, e.g. water.

Abstract: An apparatus, method and band for forming and/or dewatering a fibrous web, in which the web or a pulp suspension layer forming the same is conveyed and supported through a significant portion of its run in a paper machine by a specific processing band, while liquid such as water is simultaneously removed therefrom by hydraulically contacting the same with liquid present under vacuum or underpressure within the processing band, through a finely porous, liquid-suction surface on the band that is saturated with liquid.