Abstract: A pulp-filter arrangement (1) comprises a rotatable drum (10) and a non-rotating valve arrangement (30). The rotatable drum (10) has a cylindrical water-permeable pulp-supporting shell (14), a plurality of drain pipes (16) and a rotating hollow shaft (18). The plurality of drainpipes (16) connects the rotating hollow shaft (18) with a collecting channel (22) situated radially directly inside the cylindrical water-permeable pulp-supporting shell (14). The non-rotating valve arrangement (30) is disposed within the rotating hollow shaft (18) for sealing off the rotating hollow shaft (18) from a radially inner outlet (24) of the drain pipes (16) when respective radially inner outlet (24) is situated within a sealed zone. The non-rotating valve arrangement (30) is further arranged to, in a transition zone immediately following the sealed zone, open a throttled passage between the rotating hollow shaft (18) and the radially inner outlet (24).

Abstract: Techniques for separating cuttings from liquid include circulating a drilling fluid that comprises a liquid and formation cuttings to a scree of a screen assembly that includes screen sections; vibrating the screen assembly during circulation of the drilling fluid; while vibrating the screen assembly, separating the liquid from the plurality of formation cuttings; while vibrating the screen assembly, separating a first portion of the formation cuttings of a first size from the drilling fluid with a first screen section; rotating the screen assembly; subsequent to rotating the screen assembly and while vibrating the screen assembly, separating a second portion of the formation cuttings of a second size different than the first size from the drilling fluid with a second screen section; directing the separated liquid through the screen assembly to a liquid outlet; and directing at least one of the first or second portions of the formation cuttings to a cuttings outlet formed in the screen.

Abstract: A backwashing suction device for a fabric filtration apparatus, and more particularly, a backwashing suction device for a fabric filtration apparatus in which an edge surface of a suction slit through which pile threads exit is inclined to form a slope so that the pile threads introduced into the suction slit when a fiber disk filter is rotated for backwashing come into contact with the slope and thus the amount of angular rotation of the pile threads is increased to increase the backwashing effect. Also, since a plurality of friction protrusions are formed to protrude from the slope, the effect of removing foreign substances can be further enhanced through the effect of rubbing and washing the pile threads on a washboard while the pile threads ascend over each of the friction protrusions one by one.

Abstract: Some embodiments relate to a filtering sector for a filtering disc of a rotary filter, which includes: a structural element made up of a ribbed inner draining medium and a frame that surrounds the draining medium, which is provided with a connecting tube; and a filtering fabric that covers the structural element, wherein the structural element has a thickness which increases progressively towards the connecting tube and in that the draining medium is made up of a single sheet. The draining medium is made up of a single ribbed sheet provided with an alternation of channels, the depth of which increases as it gets closer to the mouth of the tube of the medium.

Abstract: Disclosed is a fly ring adapted to be used in a rotary drum filtering apparatus, and a method of forming such a fly ring. The fly ring comprises a plurality of ring segments, each ring segment being laser cut. Each ring segment has a first end which overlaps a second end of an adjacent ring segment, forming a lapped joint. Each ring segment first and second end has at least two spaced apart through holes, the through holes of the first end being aligned with the through holes of the second end. A custom fastener extends through the first end and second end aligned through holes.

Abstract: A method and an apparatus for washing a solids-containing suspension by means of a suction drum washer comprising a drum provided with a filtration surface, a main vacuum source such as a drop leg and washing tubes connected to the frame of the suction drum washer. A washing liquid stream is introduced by a first washing tube is directed to contact the pulp layer on the surface of the drum in a point below 10 degrees after the surface of the suspension and a vacuum of at least 0.1 bar greater than the main vacuum source, i.e. intensified suction is applied by means of a separate vacuum source to filtering surface at the contacting point of the first liquid stream and the pulp layer or maximum of 10 degrees before the contacting point. The intensified suction may be utilized also for boosting end of filtration stage (II) and drying stage (IV). Filtrate from the drying stage (IV) can be used at the same washer as a washing liquid at the first or the second washing tube.

Abstract: The present invention relates to a device and a method for reducing friction between two plates (4, 5) of a filtration unit, said plates being rotated relative to one another by being subjected to axial pressing forces, said plates being supported by the longitudinal end of a drum (1) secured to a rotary shaft (3) mounted on a bearing (6) and having internal collectors (11), and the opposite end of a casing (2) which is rotatably locked and supported by said shaft, respectively, characterized in that it includes at least one pulling system (8) engaging with the casing (2) by exerting a force intended to at least partially compensates for the axial forces pressing the plate (5) against the plate (4), in order to reduce friction while ensuring that tight mutual contact is maintained.

Abstract: A method and composition for simultaneously controlling the deposition of scale and the formation of corrosion in a cooling water system comprising adding to the system a combination of (a) a water soluble copolymer having the structure: ##STR1## wherein R.sub.1 is H or lower (C.sub.1 -C.sub.4) alkyl, F is H.sub.2 or O, M is a water soluble cation, R.sub.2 is (CH.sub.2 --CH.sub.2 --O).sub.n, ##STR2## or mixture of both, n is an integer of from 1 to about 40, R.sub.3 is H, lower (C.sub.1 -C.sub.4) alkyl or an acetate, and (b) a water soluble polymer characterized by the structural formula: ##STR3## wherein R.sub.1 is H or lower alkyl (C.sub.1 -C.sub.3); R.sub.2 is OH, OM, or NH.sub.2 ; M is a water soluble cation; R.sub.

Abstract: A process for the recovery of coal particles having a maximum dimension of less than 2 mm from coal tailings including the steps of forming a slurry (101) of tailings having a pulp density of from 10 to 30% by weight; feeding the slurry into a hydrocyclone (103) to produce an underflow second stream which contains the tailing particles over a predetermined size and some of the gangue particles smaller than that size and an overflow stream containing the coal particles smaller than the predetermined size and the balance of the gangue particles, the hydrocyclone (103) being operated such that the underflow stream has a pulp density of from 40% to 60% by weight; adjusting the pulp density of the second stream, if required, to from 20 to 50% by weight; passing the repulped second stream over a rapped or vibrated sieve screen deck (105) having a wedge wire sieve screen with a radius of less than 2 m, an arc angle of from 45.degree. to 60.degree.

Abstract: A horizontally mounted cylindrical container is adapted to mount through demountable end plates a cartridge filter in the container through demountable end plates for rotation around a lower axis than the center axis of the container. The combination of container and filter is connected in an aqueous system through a top inlet pipe and hand controlled valve and a lower front end plate outlet, and to a source of pressure cleaning media through an upper quadrant valve controlled turnable tube slidably mounted through a rear plate inlet and supported in the container by a combination track and baffle member fixed to the container top. A nozzle fixed to the free end of the pressure media tube jets cleaning media against the filter to rotate it alternately in both directions of rotation and for its full length. A second inlet pipe and valve is fixed to the top inlet pipe a chemical cleaning soak in baffled minimum amounts because of the baffling and filter mounting below the center of the container.

Abstract: A horizontal rotary table filter includes a device connecting the filter table to the carrier structure which provides freedom of movement between the two in the radial direction, to thereby maintain the filter table in a substantially planar condition under adverse operating conditions. The device preferably includes a radially oriented slideway connected to one of the table and the carrier structure, and slide shoes or rollers connected to the other of the table and the structure and disposed within the slideway. In addition to enabling relative radial movement, the device is so constructed as to provide a space between the table and the structure and thereby thermally insulate one from the other. Also disclosed is a more stable carrier structure which includes circumferential and diagonal connecting members disposed between adjacent radial gussets.

Abstract: An improved rotary drum filter is described. The filter includes a liquid collection means communicating with at least a plurality of fluid conduits. The collection means collect and discharge residual liquid remaining in the fluid conduits during each rotation of the filter drum to decrease the erosive effects of the residual liquid on the filter cloth.

Abstract: The invention provides a discharge roller for a vacuum belt filter, over which a filter cloth of the filter passes, the roller having a channelling means in the form of a plurality of longitudinally directed and circumferentially spaced-apart passages which are each in communication with a different segment of the cylindrical surface of the roller via suitable radially directed bores and an end valve for directing a discharge fluid to those passages which are in communication, at any particular time, with that portion of the cylindrical surface engaged by the filter cloth, such that there is flow of the discharge fluid in a reverse direction through the cloth to separate residue cake therefrom.