Patent Publication Number: US-2020289962-A1

Title: High-pressure filter

Description:
TECHNICAL FIELD 
     The present invention relates to the field of filter technologies, and in particular, to a high-pressure filter. 
     BACKGROUND 
     A ceramic filter is a new common high-efficiency and energy-saving solid-liquid separation device in the world. The ceramic filter mainly consists of several parts including a roller system, a stirring system, a feeding and discharging system, a vacuum system, a gas distribution system, a filtrate discharging system, a scraping system, a backwashing system, a combined cleaning (ultrasonic cleaning and automatic acid cleaning) system, an automatic control system, a tank body, and a frame. The core part of the filter is a ceramic filter plate, which is also referred to as a ceramic filter film, a ceramic board, a ceramic plate, a filter plate, etc., and is a new filter medium made of corundum, silicon carbide, and so on through special techniques. The ceramic filter plate has the following defects. The ceramic filter plate has a high cost of use, mainly a high cleaning cost, has a complex structure, and needs to be equipped with pickling and ultrasonic systems, thus polluting the environment. The ceramic filter plate is easily blocked, has a short service life and low mechanical strength, and is easily broken during backwashing and vacuuming and not resistant to low temperature. Moreover, due to the limitation of the material, the filtering area cannot be too large, so that the whole machine cannot be enlarged. 
     SUMMARY OF THE INVENTION 
     The technical task of the present invention is to provide a high-pressure filter to solve the defects of the prior art, and in particular to improve the filtering environment and improve the filtering efficiency of the whole machine. 
     The technical solution adopted by the present invention to solve the technical problem thereof is: 
     A high-pressure filter comprises: a slurry filled trough, a filter disc built into the trough, and a power device for driving the filter disc to rotate about its own axis. A sealed housing is disposed outside the trough, and an inner wall of the sealed housing is connected to an outer wall of the trough to form a sealed cavity, the surface of the sealed housing is provided with a liquid inlet in communication with the sealed cavity, and an ultrasonic liquid level controller is mounted at the position of the liquid inlet. The filter disc further includes a screw shaft and a filter disc body; two ends of the screw shaft penetrate through the sealed housing outwardly through a bearing block, an end portion of the screw shaft extending out of the sealed housing is provided with a filter cake thickness ultrasonic detector, an end surface of the screw shaft is provided with an axial hole, the surface of the screw shaft is provided with a radial hole in communication with the axial hole, and an end portion of the screw shaft not having an axial hole is connected to the power device. The filter disc body is fixed to the screw shaft, a central axis of the filter disc body coincides with a central axis of the screw shaft, the radial hole is provided at a position where the filter disc body is fixed to the screw shaft, and a filtrate flowing into the filter disc body enters the axial hole through the radial hole of the screw shaft and is discharged outwardly from the sealed cavity. 
     The high-pressure filter further comprises a spiral stirring device and a compressed air storage tank. The spiral stirring device is built in the bottom of the trough and under the filter disc. The compressed air storage tank is externally placed on the sealed housing, and an outlet end of the compressed air storage tank is in communication with the sealed cavity downwardly. 
     Optionally, the high-pressure filter further comprises a scraper and a screw discharging device. The scraper is mounted to the trough or the inner wall of the sealed housing, the scraper is located at a side of the filter disc, the screw discharging device is externally disposed on the sealed housing, and a feeding end of the screw discharging device is in communication with the sealed cavity upwardly. When the power device drives the filter disc to rotate, the scraper scrapes off a filter cake on the surface of the filter disc so that the filter cake falls from the sealed cavity into the feeding end of the screw discharging device. 
     Optionally, the filter disc body includes a support plate and a sintered mesh tightly wrapped around an outer surface of the support plate. The support plate is a disc structure having an intermediate opening. The support plate includes a first support plate body, a second support plate body, and a seal ring. Surfaces of the first support plate body and the second support plate body are provided with a plurality of through holes, the first support plate body and the second support plate body are symmetrically parallel, the seal ring is located between the first support plate body and the second support plate body, and the seal ring is sealingly connected to outer edges of the first support plate body and the second support plate body. 
     Optionally, the sintered mesh includes a protective layer, a filter layer, a flow guiding layer, and a base layer in sequence from the outside in, and the pore density of the filter layer is much smaller than the pore densities of the protective layer, the flow guiding layer, and the base layer. 
     Preferably, the support plate is selected from a perforated plate or engineering plastic. Preferably, the number of the screw shaft is one, and the number of the filter disc body is 1 to 20. 
     Optionally, the number of the screw shaft is at least two, a screw shaft connected to the power device is provided with an axial hole, the other screw shaft is provided with an axial through hole, and adjacent screw shafts are arranged in series and screwed to form a linear filtering passage; the number of the filter disc body is the same as the number of the screw shaft, and the filter disc bodies are fixed to the screw shafts one-to-one correspondingly. 
     Optionally, the surface of the sealed housing is provided with a sight glass. 
     Optionally, the high-pressure filter further comprises a backwashing system. The backwashing system is located at an axial hole end of the screw shaft, and a water outlet end of the backwashing system is fitted to the axial hole of the screw shaft. 
     Optionally, the screw shaft is connected to the sealed housing through the bearing block, and a mechanical seal is mounted between the bearing block and the sealed housing. 
     The beneficial effects of a high-pressure filter of the present invention compared to the prior art are as follows. 
     1) The present invention is simple in structure and small in volume. The inner wall of the sealed housing is connected to the outer wall of the trough to form the sealed cavity, the compressed air storage tank is in communication with the sealed cavity, and the compressed air is supplied to the sealed cavity to form a high pressure environment in the sealed cavity. Therefore, a pressure difference is formed between the interior and the exterior of the filter disc to improve the filtering efficiency. 
     2) The filter disc of the present invention can be enlarged to more than 20 square meters per turn. The sintered mesh is used as a filter material, which has uniform and stable filtering precision and extremely high mechanical strength and compressive strength. The filtering mechanism is surface filtering, and pores of the mesh are smooth, so the filter disc has excellent backwash regeneration performance, and can be used repeatedly for a long time. Backwash is required for only one minute once every 4 to 8 hours, and does not need pickling or shutdown, thus being especially suitable for continuous and automated operations. 
     3) The filter of the present invention has the advantages of small volume and high filtering efficiency, and the backwashing system can also reduce the probability of clogging accidents in the filtering process and the use cost, increase the filtering time, and improve the throughput. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a structural front view of Embodiment  1  according to the present invention; 
         FIG. 2  is a cross-sectional view taken along the line M-M of  FIG. 1 ; 
         FIG. 3  is a partially enlarged cross-sectional structural view of a filter disc according to Embodiment 1; 
         FIG. 4  is an enlarged structural view of A in  FIG. 3 ; 
         FIG. 5  is an enlarged view of a partial surface of a first perforated plate body of  FIG. 3 ; 
         FIG. 6  is an enlarged structural view of B in  FIG. 3 ; and 
         FIG. 7  is a partially enlarged cross-sectional structural view of the filter disc according to Embodiment 2. 
     
    
    
     Reference numerals in the drawings each denote: 
       100 . Backwashing system,  200 . Trough,  300 . Filter disc,  400 . Power device, 
       500 . Scraper,  600 . Screw discharging device,  700 . Compressed air storage tank, 
       800 . Spiral stirring device; 
       210 . Sealed housing,  220 . Sealed cavity,  230 . Liquid inlet,  240 . Sight glass; 
       310 . Screw shaft,  311 . Axial hole,  312 . Radial hole,  313 . Axial through hole; 
       320 . Filter disc body,  330 . Perforated plate,  340 . Sintered mesh; 
       331 . First perforated plate body,  332 . Second perforated plate body,  333 . Seal ring, 
       334 . Through hole,  335 . Groove; 
       510 . Blade; 
       341 . Protective layer,  342 . Filter layer,  343 . Flow guiding layer,  344 . Base layer; 
     A. Ultrasonic liquid level controller, b. Filter cake thickness ultrasonic detector; 
     reference numerals {circle around (1)}{circle around (2)}{circle around (3)} in  FIG. 7  denote screw shafts which are sequentially connected in series, wherein a right end of the screw shaft denoted by the reference numeral {circle around (1)} is connected to the power device. 
     DETAILED DESCRIPTION 
     Exemplary embodiments of this disclosure will be described in more detail below with reference to the accompanying drawings of the specification. Exemplary embodiments of this disclosure are shown in the accompanying drawings of the specification; however, it should be understood that this disclosure can be implemented in various forms rather than being limited by the embodiments described here. In contrast, these embodiments are provided so that this disclosure can be understood more thoroughly and the scope of this disclosure can be fully conveyed to those skilled in the art. 
     In order to better illustrate the present invention, the technical solution will be further described now in conjunction with the specific embodiments and the accompanying drawings. These specific embodiments are described in the embodiments; however, they are not intended to limit the present invention. Some variations and modifications can be made by any of ordinary skill in the art without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to that defined by the claims. 
     Embodiment 1 
     As shown in  FIG. 1  and  FIG. 2 , the present invention provides a high-pressure filter, including a slurry filled trough  200 , a filter disc  300  built into the trough  200 , and a power device  400  for driving the filter disc  300  to rotate about its own axis. A sealed housing  210  is disposed outside the trough  200 , and an inner wall of the sealed housing  210  is connected to an outer wall of the trough  200  to form a sealed cavity  220 , the surface of the sealed housing  210  is provided with a liquid inlet  230  in communication with the sealed cavity  220 , and an ultrasonic liquid level controller a is mounted at the position of the liquid inlet  230 . 
     As shown in  FIG. 3  to  FIG. 6 , in order to achieve good filtering, the structure of the filter disc  300  specifically includes a screw shaft  310  and twelve filter disc bodies  320 . Two ends of the screw shaft  310  penetrate through the sealed housing  210  outwardly through a bearing block, an end portion of the screw shaft  310  extending out of the sealed housing  210  is provided with a filter cake thickness ultrasonic detector b, a left end surface of the screw shaft  310  is provided with an axial hole  311 , the surface of the screw shaft  310  is provided with twelve radial holes  312  in communication with the axial hole  311 , and a right end portion of the screw shaft  310  is connected to the power device. The filter disc body  320  is fixed to the screw shaft  310 , a central axis of the filter disc body  320  coincides with a central axis of the screw shaft  310 , the radial hole  312  is provided at a position where the filter disc body  320  is fixed to the screw shaft  310 , and a filtrate flowing into the filter disc body  320  enters the axial hole  311  through the radial hole  312  of the screw shaft  310  and is discharged outwardly from the sealed cavity  220 . 
     As shown in  FIG. 3  and  FIG. 6 , a perforated plate body is used as an example in this embodiment. The filter disc body  320  includes a perforated plate  330  for supporting and a sintered mesh  340  tightly wrapping the perforated plate  330 . 
     As shown in  FIG. 3 ,  FIG. 4 ,  FIG. 5 , and  FIG. 6 , the perforated plate  330  is a disc structure having an intermediate opening, and the sintered mesh  340  is tightly wrapped around an outer surface of the perforated plate  330 . The perforated plate  330  includes a first perforated plate body  331 , a second perforated plate body  332 , and a seal ring  333 . Surfaces of the first perforated plate body  331  and the second perforated plate body  332  are provided with a plurality of through holes  334  respectively. The first perforated plate body  331  and the second perforated plate body  332  are symmetrically parallel. The seal ring  333  is located between the first perforated plate body  331  and the second perforated plate body  332 , and the seal ring  333  is sealingly connected to outer edges of the first perforated plate body  331  and the second perforated plate body  332 . As such, liquid after being filtered by the filter disc body  320  will pass through the sintered mesh  340 , and then enter a filtering cavity enclosed by the first perforated plate body  331 , the second perforated plate body  332 , and the seal ring  333 . Finally, the liquid flows into the axial hole  311  through the radial holes  312  of the screw shaft  310 , and is then discharged from the sealed cavity outwardly. It should be noted that a plurality of grooves  335  may further be disposed on the surfaces of the first perforated plate body  331  and the second perforated plate body  332 , thus better implementing the connection between the first perforated plate body  331 , the second perforated plate body  332 , and the seal ring  333 . The plurality of grooves  335  are classified into at least two groups. Adjacent grooves  335  in the same group are connected to form a straight line perpendicular to the central axis of the screw shaft  310 . The through holes  334  are located between grooves  335  in adjacent groups. The grooves  335  in different perforated plate bodies are welded, thus implementing fixed connection between the first perforated plate body  331  and the second perforated plate body  332 , thereby implementing the fixed connection between the first perforated plate body  331 , the second perforated plate body  332 , and the seal ring  333 . 
     As shown in  FIG. 3  and  FIG. 6 , the sintered mesh  340  includes a protective layer  341 , a filter layer  342 , a flow guiding layer  343 , and a base layer  344  in sequence from the outside in, and the pore density of the filter layer  342  is much smaller than the pore densities of the protective layer  341 , the flow guiding layer  343 , and the base layer  344 . 
     As shown in  FIG. 1  and  FIG. 2 , the high-pressure filter further includes a spiral stirring device  800  and a compressed air storage tank  700 . The spiral stirring device  800  is built in the bottom of the trough  200  and under the filter disc  300 ; the compressed air storage tank  700  is externally placed on the sealed housing  210 , and an outlet end of the compressed air storage tank  700  is in communication with the sealed cavity  220  downwardly 
     As shown in  FIG. 1  and  FIG. 2 , the high-pressure filter further includes a scraper  500  and a screw discharging device  600 . The scraper  500  is mounted to the trough  200  and located at a side of the filter disc  300 . The screw discharging device  600  is externally disposed on the sealed housing  210 , and a feeding end of the screw discharging device  600  is in communication with the sealed cavity  220  upwardly. When the power device drives the filter disc  300  to rotate, the scraper  500  scrapes off a filter cake on the surface of the filter disc  300  so that the filter cake falls from the sealed cavity  220  into the feeding end of the screw discharging device  600 . 
     As shown in  FIG. 1  to  FIG. 6 , in this embodiment, during operation, the power device  400  drives the screw shaft  310  to rotate, the filter disc  300  rotates synchronously with the screw shaft  310 , and the filter disc  300  filters the slurry in the trough  200  during the rotation. The sealed cavity forms a high-pressure environment under the action of the compressed air storage tank  700 . The filtrate of the slurry filtered by the filter disc  300  enters the filtering cavity enclosed by the first perforated plate body  331 , the second perforated plate body  332 , and the seal ring  333 , then flows into the axial hole  311  through the radial hole  312  of the screw shaft  310 , and discharged from the sealed cavity through the axial hole  311  outwardly to achieve high pressure filtering. During the rotation of the filter disc  300 , when the filter disc  300  leaves the slurry, a filter cake is formed on the surface of the filter disc  300  due to the accumulation of slurry impurities. When the filter disc  300  is rotated again to be immersed in the slurry, the scraper  500  fixed to the trough  200  scrapes off a filter cake formed on the surface of the filter disc  300 , and the filter cake falls under the guiding action of the scraper  500  from the sealed cavity  220  into the feed end of the screw discharging device  600 . Therefore, the filter disc  300  immersed in the slurry can better carry out the filtering work. 
     Embodiment 2 
     Referring to  FIG. 7  with reference to  FIG. 1  to  FIG. 6 , the difference from Embodiment 1 is that the number of the screw shaft  310  is at least two. With reference to Embodiment 1, the number of the screw shaft  310  should be twelve. The rightmost screw shaft  310  is connected to the power device  400 , and is provided with an axial hole  311 . The other screw shafts  310  are provided with axial through hole  313 , and adjacent screw shafts  310  are arranged in series and screwed to form a linear filtering passage. The number of the filter disc body  320  is the same as the number of the screw shaft  310 , and the filter disc bodies  320  are fixed to the screw shafts  310  one-to-one correspondingly. 
     The filter further includes a backwashing system  100 . The on and off of the backwashing system  100  is controlled by a PLC system. The backwashing system  100  is located at the axial hole  311  end of the screw shaft  310 , and a water outlet end of the backwashing system  100  is in communication with the axial hole  311  of the screw shaft  310 . In addition to the scraper  500  scraping off the filter cake formed on the surface of the filter disc  300 , the filter disc  300  can also be backwashed by the backwashing system  100 . The PLC system is operated, the backwashing system  100  is activated, and the water outlet end of the backwashing system  100  is connected to the axial hole  311  of the screw shaft  310 . The water discharged by the backwashing system  100  flows through the axial hole  311  of the screw shaft  310 , the radial hole  312  of the screw shaft  310 , enters the filtering cavity enclosed by the first perforated plate body  331 , the second perforated plate body  332 , and the seal ring  333 , and then passes through the through holes  334  on the surfaces of the first perforated plate body  331  and the second perforated plate body  332  and through the sintered mesh  340  outwardly, thereby achieving backwashing of the filter disc  300 , improving the filtering effect, and avoiding the occurrence of clogging. 
     In addition, for Embodiment 1 and Embodiment 2, it is necessary to supplement that the support plate can also be selected from engineering plastic with high strength and corrosion resistance. The surface of the engineering plastic is also provided with a plurality of through holes. The structure layout and the installation are all identical to the structural layout and the installation of the perforated plate, and will not be elaborated here. 
     The present invention has been described according to a limited number of embodiments; however, being taught by the above description, those skilled in the art should understand that other embodiments can be conceived within the scope of the present invention as described. 
     In addition, it should be noted that the language used in the specification has been selected primarily for the purpose of readability and teaching, and is not selected for interpreting or limiting the theme of the present invention. Therefore, many modifications and variations without departing from the scope and spirit of the appended claims will be apparent to those of ordinary skill in the art. The disclosure of the present invention is intended to be illustrative rather than restrictive, and the scope of the present invention is defined by the appended claims.