Municipal sludge treatment device and treatment method

Abstract

The invention discloses a municipal sludge treatment device and a treatment method. The treatment device comprises a pretreatment tank, an ultrasonic mechanism and a centrifugal dewatering mechanism which are communicated with one another, the pretreatment tank is used for controlling the pH value of sludge before treatment, and the ultrasonic mechanism is used for changing the internal structure of the sludge by utilizing ultrasonic waves; the centrifugal dewatering mechanism comprises an equipment rack, a housing mounted at the top of the equipment rack, and a rotary drum rotationally connected to the equipment rack; a spiral pusher is rotationally connected to the inner side of the rotary drum, a plurality of slag discharging openings are formed in the end, with the smaller diameter, of the rotary drum, and a plurality of overflow holes are formed in the end, with the larger diameter, of the rotary drum; the pH value is regulated and controlled, so that the sludge reaches a certain acidic condition before being treated, microbial cell walls and EPS net structures in the sludge are damaged through ultrasonic treatment, then a flocculating agent and the sludge are subjected to centrifugal dewatering together, the water content of the sludge obtained after treatment can be as low as 60% or below, and the sludge shows better dewatering performance.

Description

Technical Field

[0001] The present invention relates to the technical field of sludge treatment, and in particular to a municipal sludge treatment device and a treatment method. Background Art

[0002] With the acceleration of urbanization, the amount of sludge generated in the process of municipal sewage treatment is increasing. Sludge treatment is a crucial link, which is directly related to the efficiency of environmental protection and resource recycling. At present, the traditional methods for treating municipal sludge mainly include physical methods (such as mechanical dehydration and thermal drying), chemical methods (such as drug addition and chemical oxidation) and biological methods (such as anaerobic digestion and aerobic composting).

[0003] As a by-product of sewage treatment, sludge has a complex composition, especially in sludge with high organic matter content, which is rich in microbial cell walls and extracellular polymers (EPS). These components are mainly composed of high molecular weight compounds such as polysaccharides, proteins, and lipids. They form a complex network structure in the sludge, which greatly increases the viscosity and water retention of the sludge, making traditional dehydration methods inefficient and difficult to achieve ideal dehydration effects.

[0004] Therefore, it is necessary to improve the deficiencies in the prior art to solve the above problems. Summary of the invention

[0005] The present invention overcomes the shortcomings of the prior art and provides a municipal sludge treatment device and a treatment method. To achieve the above purpose, the technical solution adopted by the present invention is: a municipal sludge treatment device, comprising: a pretreatment tank, an ultrasonic mechanism and a centrifugal dehydration mechanism that are interconnected; the pretreatment tank is used to control the pH value of the sludge before treatment, and the ultrasonic mechanism is used to change the internal structure of the sludge by using ultrasonic waves;

[0006] The centrifugal dehydration mechanism comprises: an equipment frame, a cover shell installed on the top of the equipment frame, and a drum rotatably connected to the equipment frame; a spiral pusher is rotatably connected to the inner side of the drum, a plurality of slag discharge ports are opened at the end with a smaller diameter of the drum, and a plurality of overflow holes are opened at the end with a larger diameter;

[0007] A plurality of feed ports are provided on the side of the spiral propeller, and a feed pipe is rotatably connected to one end of the rotating drum located outside the cover shell. A connecting feed component for achieving uniform feeding into the rotating drum is provided between the feed pipe and the plurality of feed ports, and a drug introduction component for adding flocculant into the feed pipe is provided on the feed pipe. The equipment frame is provided with a plurality of power sources for respectively driving the rotating drum and the spiral propeller to rotate.

[0008] In a preferred embodiment of the present invention, the connecting feed assembly includes: a connecting flow channel opened on the inner side of the spiral pusher, a material distribution cavity opened at one end of the connecting flow channel, and a V-shaped stopper fixed on the inner side of the material distribution cavity; the feed pipe is connected with the connecting flow channel, the material distribution cavity and several feed ports in sequence, and arc-shaped transition structures are provided at both sides of the V-shaped stopper and the feed port.

[0009] In a preferred embodiment of the present invention, the drug introducing assembly includes: an annular tube sleeved on the side of the feed pipe, a plurality of drug introducing heads fixed on the inner side of the annular tube, and a drug introducing tube fixed on the side of the annular tube; one end of the drug introducing tube is connected to a first drug doser for quickly stirring the mixed medicine through a pipeline, and one end of a plurality of the drug introducing heads penetrates into the inner side of the feed pipe.

[0010] In a preferred embodiment of the present invention, a differential is installed at one end of the spiral pusher located outside the cover shell, and the plurality of power sources are respectively connected to one end of the drum located outside the cover shell and one end of the differential; a slag discharge pipe and a liquid discharge pipe are fixed to the bottom of the equipment frame, the slag discharge pipe is located at the bottom of the slag discharge port, and the liquid discharge pipe is located at the bottom of the overflow hole.

[0011] In a preferred embodiment of the present invention, the top of the pretreatment tank is connected to a second doser for rapidly stirring and mixing the reagents through a pipeline, and the inner bottom of the pretreatment tank is provided with an agitator for stirring the sludge inside the pretreatment tank.

[0012] In a preferred embodiment of the present invention, the ultrasonic mechanism includes: a plurality of Y-shaped processing tubes, a plurality of amplitude rods installed on the top of the inner side of the plurality of Y-shaped processing tubes, and a plurality of ultrasonic transducers installed on one end of the plurality of amplitude rods located on the outer side of the Y-shaped processing tubes; the input ends of the plurality of ultrasonic transducers are electrically connected to an ultrasonic generator, and the plurality of Y-shaped processing tubes are connected in series with each other.

[0013] In a preferred embodiment of the present invention, a feed pipe is fixed on one side of the pretreatment tank, a first connecting pipe is fixed between the pretreatment tank and the Y-shaped treatment pipe, a second connecting pipe is fixed between the Y-shaped treatment pipe and the feed pipe, and plunger pumps are installed on the feed pipe, the Y-shaped treatment pipe and the feed pipe.

[0014] The present invention provides a treatment method for a municipal sludge treatment device, comprising the following steps:

[0015] S1. Pass the sludge to be treated into the pretreatment tank and use an acidic solution to adjust the pH value of the sludge;

[0016] S2, passing the pH-adjusted sludge through an ultrasonic device to destroy the microbial cell walls and the network structure of the extracellular polymers in the sludge by using ultrasonic waves;

[0017] S3, passing the ultrasonically treated sludge into the feed pipe, during which the sludge is passed into the feed pipe, adding flocculant to the sludge through the drug introduction component, and connecting the feed component so that the sludge is evenly distributed into the drum through the feed port;

[0018] S4. While introducing sludge into the feed pipe, the power source drives the drum and the screw pusher to rotate in the same direction, so that the sludge entering the drum is evenly distributed. The solid particles with a density greater than that of the liquid phase are settled on the inner wall of the drum by centrifugal force. The screw pusher is used to push the solid phase to the discharge port at the smaller diameter end of the drum for discharge, and the separated liquid phase is discharged from the overflow hole at the larger diameter end, thereby completing the sludge dehydration process.

[0019] In a preferred embodiment of the present invention, in the step S1, the acidic solution is one of sulfuric acid or hydrochloric acid, and the pH value of the sludge is 2.9-3.5; in the step S2, the ultrasonic power of the ultrasonic mechanism is 20-30%, and the processing time is 10-30min; in the step S3, the flocculant is one of polyacrylamide or polyaluminum chloride, the amount of the flocculant in the sludge is 2.2-2.8kg / t, and the addition flow rate of the flocculant is 44-56kg / h.

[0020] In a preferred embodiment of the present invention, in the step S4, the rotation speed of the drum is 2000-2300 r / min, and the rotation speed of the spiral pusher is slightly lower than the rotation speed of the drum.

[0021] The present invention solves the defects existing in the background technology and has the following beneficial effects:

[0022] (1) The present invention provides a municipal sludge treatment device and method, which adjusts the pH value to achieve a certain acidic condition before the sludge is treated, and uses ultrasonic treatment to destroy the microbial cell wall and EPS network structure in the sludge, and then uses a flocculant to centrifuge and dehydrate the sludge together. The moisture content of the sludge obtained after treatment can be reduced to less than 60%, so that it exhibits better dehydration performance.

[0023] (2) In the present invention, a connecting feed assembly is provided between the feed pipe and a plurality of feed ports. When the sludge enters the feed pipe, the feed pipe, the connecting flow channel, the distribution chamber, the V-shaped stopper and the arc-shaped transition structure cooperate to gradually decelerate and smoothly transition the sludge from the distribution chamber through the feed port into the drum, thereby effectively reducing the disordered flow of the sludge into the drum, avoiding the turbulence and eddy current caused by uneven flow velocity, and helping to reduce the local accumulation and eddy current of the sludge in the pipeline, ensuring that the sludge is evenly distributed in the drum, and further preventing the flocs generated by the flocculant in the sludge from being unevenly distributed in the drum and affecting the dehydration effect, so that the centrifugal force generated by the flocculant acts evenly on the sludge in different areas inside the drum.

[0024] (3) In the present invention, by setting up a pretreatment tank, with the cooperation of the second doser and the agitator, the pH value of the sludge in the pretreatment tank can be regulated by using an acidic solution. The acidic environment can promote the hydrolysis of polysaccharides and proteins in the microbial cell walls in the sludge, destroy the structure of the cell walls, reduce the cell wall's ability to adsorb water, and destroy the stability of the microbial cell walls and EPS in the sludge, thereby reducing the viscosity and water holding capacity of the sludge. Since the flocculant is more likely to combine with the partially depolymerized particles, it helps to provide a more flocculating environment for the flocculant in the subsequent flocculation treatment.

[0025] (4) In the present invention, after the pH value of the sludge is adjusted by setting an ultrasonic mechanism, the Y-shaped treatment tube, the ultrasonic generator, the amplitude transformer and the ultrasonic transducer are coordinated to generate strong mechanical vibration and pressure waves to the sludge in the Y-shaped treatment tube, so that the microbial cell wall and the EPS (extracellular polymer) network structure in the sludge are destroyed, and the tightly bound water is released. At the same time, a cavitation effect can be generated in the sludge, that is, tiny bubbles are formed in the liquid. The rapid formation and collapse of the bubbles can generate strong shear force, thereby further destroying the network structure in the sludge, releasing more free water and smaller particles, so that the particles are more easily aggregated into larger flocs under the subsequent flocculation effect, which helps to improve the efficiency of subsequent centrifugal dehydration.

[0026] (5) In the present invention, a drug introduction component is provided on the feed pipe. After the premixed flocculant is introduced into the drug introduction pipe, the flocculant can be evenly delivered from the side of the feed pipe into the sludge flowing in the feed pipe through the cooperation of the drug introduction pipe, the annular tube, the drug introduction head and the feed pipe. Furthermore, when the sludge is introduced into the feed pipe, the flocculant can be introduced together to react with the organic matter in the sludge, so that the tiny particles in the sludge are aggregated into larger flocs, forming flocs with better dehydration performance, thereby improving the sludge dehydration effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 is a schematic structural diagram of a municipal sludge treatment device according to a preferred embodiment of the present invention;

[0029] Figure 2 It is a half-section structural diagram of a centrifugal dehydration mechanism of a preferred embodiment of the present invention;

[0030] Figure 3 2 is a half-section structural diagram of a spiral pusher of a preferred embodiment of the present invention;

[0031] Figure 4 It is a structural diagram of the connection between the drug introduction component and the feed pipe of the preferred embodiment of the present invention;

[0032] In the figure: 1. pretreatment tank; 2. ultrasonic mechanism; 21. Y-type treatment tube; 22. amplitude rod; 23. ultrasonic transducer; 24. ultrasonic generator; 3. centrifugal dehydration mechanism; 31. equipment frame; 32. cover; 33. drum; 34. spiral pusher; 35. slag discharge port; 36. overflow hole; 37. feed port; 38. feed pipe; 39. differential; 4. connecting flow channel; 41. material distribution cavity; 42. V-shaped stopper; 43. arc transition structure; 5. annular tube; 51. drug introduction head; 52. drug introduction pipe; 53. first dosing device; 6. slag discharge pipe; 61. liquid discharge pipe; 7. second dosing device; 8. agitator; 9. feed pipe; 91. first connecting pipe; 92. second connecting pipe; 93. plunger pump. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0035] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention, unless otherwise specified, "multiple" means two or more.

[0036] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0037] It should be noted that the municipal sludge treatment device is preferably suitable for dehydrating municipal sludge with a high organic matter content, and the organic matter content of the sludge is preferably 33%-45%.

[0038] like Figure 1 and Figure 2 As shown, a municipal sludge treatment device comprises: a pretreatment tank 1, an ultrasonic mechanism 2 and a centrifugal dehydration mechanism 3 which are interconnected; the pretreatment tank 1 is used to control the pH value of the sludge before treatment, and the ultrasonic mechanism 2 is used to change the internal structure of the sludge by using ultrasonic waves; the centrifugal dehydration mechanism 3 comprises: an equipment frame 31, a cover 32 installed on the top of the equipment frame 31, and a drum 33 rotatably connected to the equipment frame 31; a spiral pusher 34 is rotatably connected to the inner side of the drum 33, and a plurality of rows of A slag outlet 35 is provided at one end with a larger diameter and a plurality of overflow holes 36 are provided; a plurality of feed ports 37 are provided on the side of the screw propeller; a feed pipe 38 is rotatably connected to one end of the rotating drum 33 located outside the cover shell 32; a connecting feed assembly for uniformly feeding the rotating drum 33 is provided between the feed pipe 38 and the plurality of feed ports 37; a drug introduction assembly for adding flocculant into the feed pipe 38 is provided on the feed pipe 38; and a plurality of power sources for driving the rotating drum 33 and the screw pusher 34 to rotate are provided on the equipment frame 31.

[0039] It should be noted that one side of the cover 32 is hinged to the top of the equipment frame 31, and the other side is clamped to the top of the equipment frame 31, and the connection between the cover 32 and the equipment frame 31 is sealed; the drum 33 is located inside the cover 32, and one end of the drum 33 and one end of the spiral pusher 34 are rotatably connected to the top of the equipment frame 31 through a bearing seat, and the side of the feed pipe 38 is fixed to the top of the equipment frame 31 by a support block; after passing through the pretreatment tank 1 and the ultrasonic mechanism 2 in turn, the sludge is respectively regulated in pH value and treated with ultrasonic waves, and then the sludge is passed into the feed pipe 38, and with the cooperation of the drug introduction component, a flocculant is introduced into the sludge in the feed pipe 38, so that with the cooperation of the connected feed component, the sludge is evenly distributed through the feed port 37 and enters the inside of the drum 33, and at the same time At the same time, the power source cooperates to drive the drum 33 and the screw pusher 34 to rotate in the same direction respectively, and the rotation speed of the screw pusher 34 is slightly lower than the rotation speed of the drum 33, so that the sludge evenly distributed into the drum 33 can be effectively destroyed by the strong centrifugal force generated by the high-speed rotation of the drum 33. The colloidal structure in the sludge can be effectively destroyed, and the solid phase particles with a density greater than that of the liquid phase can be settled to the inner wall of the drum 33. At the same time, due to the different rotation speeds of the screw pusher 34 and the drum 33, the relative movement between the two (i.e., the speed difference) can push the solid phase deposited on the inner wall of the drum 33 to the slag discharge port 35 at the smaller diameter end of the drum 33 for discharge, and the separated liquid phase is discharged from the overflow hole 36 at the larger diameter end, which can achieve rapid dehydration of the sludge and shorten the treatment cycle, thereby improving the dehydration effect and treatment efficiency.

[0040] like Figure 2 and Figure 3 As shown, in some embodiments, the connecting feed assembly includes: a connecting flow channel 4 opened on the inner side of the spiral pusher 34, a distribution cavity 41 opened at one end of the connecting flow channel 4, and a V-shaped stopper 42 fixed on the inner side of the distribution cavity 41; the feed pipe 38 is connected with the connecting flow channel 4, the distribution cavity 41 and a plurality of feed ports 37 in sequence, and arc-shaped transition structures 43 are provided on both sides of the V-shaped stopper 42 and the feed ports 37.

[0041] It should be noted that the connecting flow channel, the feed pipe 38, the rotating drum 33 and the spiral pusher 34 are coaxially arranged, the inner diameter of the connecting flow channel 4 is the same as the inner diameter of the feed pipe 38, the inner side of the connecting flow channel 4 is rotatably connected to the connection at one end of the feed pipe 38, and is sealed; the V-shaped stopper 42 has a smaller cross-sectional area and the end is opposite to the connecting flow channel 4, and is coaxially arranged; when the sludge passes into the feed pipe 38, the sludge can enter the interior of the connecting flow channel 4 along the feed pipe 38, and after entering the interior of the distribution chamber 41 through the connecting flow channel 4, since the V-shaped stopper 42 has a smaller cross-sectional area and the end is opposite to the connecting flow channel 4, and is coaxially arranged, the V-shaped stopper 42 can guide the sludge to several feeds The flow direction of the feed port 37 and the arc-shaped transition structure 43 on both sides of the V-shaped stopper 42 and the feed port 37 can gradually slow down and smoothly transition the sludge when it enters the drum 33 from the material distribution chamber 41 through the feed port 37, effectively reducing the disordered flow of the sludge into the drum 33, avoiding the turbulence and eddy current caused by uneven flow velocity, helping to reduce the local accumulation and eddy current of the sludge in the pipeline, ensuring that the sludge is evenly distributed in the drum 33, and further preventing the flocs generated by the flocculant in the sludge from being affected by the uneven distribution in the drum 33, thereby affecting the dehydration effect, so that the centrifugal force generated by it acts evenly on the sludge in different areas inside the drum 33.

[0042] like Figure 1 and Figure 4 As shown, in some embodiments, the drug introducing assembly includes: an annular tube 5 sleeved on the side of the feed pipe 38, a plurality of drug introducing heads 51 fixed on the inner side of the annular tube 5, and a drug introducing tube 52 fixed on the side of the annular tube 5; one end of the drug introducing tube 52 is connected to a first drug doser 53 for quickly stirring the mixed medicine through a pipeline, and one end of the plurality of drug introducing heads 51 penetrates into the inner side of the feed pipe 38.

[0043] It should be noted that the annular tube 5 is coaxially arranged with the feed tube 38, and a plurality of drug introduction heads 51 are evenly distributed on the inner side of the annular tube 5 in the circumferential direction; the first drug feeder 53 has the function of rapidly stirring and mixing the solid and the liquid. When the flocculant is added to the feed tube 38 through the drug introduction tube 52, the flocculant can be pre-mixed through the first drug feeder 53, and then the flocculant that can react quickly is added to the feed tube 38 to increase the reaction rate; when the first drug feeder 53 passes the pre-mixed flocculant into the feed tube 38, the flocculant can be pre-mixed and reacted. After the drug introduction tube 52, the flocculant can enter the annular tube 5, and through the several drug introduction heads 51 evenly distributed on the inner side of the annular tube 5, the flocculant can be evenly fed into the sludge flowing in the feed pipe 38 from the side of the feed pipe 38. Then, when the sludge is introduced into the feed pipe 38, the flocculant can be introduced together to react with the organic matter in the sludge, and the tiny particles in the sludge are aggregated into larger flocs, forming flocs with better dehydration performance, thereby improving the sludge dehydration effect.

[0044] like Figure 2 As shown, in some embodiments, a differential 39 is installed at one end of the screw pusher 34 located outside the housing 32, and a plurality of power sources are respectively connected to one end of the drum 33 located outside the housing 32 and one end of the differential 39.

[0045] It should be noted that the specific structure of the power source is a mechanical structure in the prior art that can transmit the rotational force to one end of the drum 33 or one end of the differential 39 for rotational motion at a certain transmission ratio, and at least includes: a motor installed on the top of the equipment frame 31, an active synchronous pulley installed at the output end of the motor, and a driven synchronous pulley installed at one end of the drum 33 or one end of the differential 39; a synchronous belt meshing between the active synchronous pulley and the driven synchronous pulley, when driving, the motor provides a rotational force to drive the active synchronous pulley to rotate synchronously, and the meshing of the synchronous belt drives the driven synchronous pulley to rotate, and then the rotational force of the motor can be transmitted to one end of the drum 33 or one end of the differential 39 at a certain transmission ratio for rotational motion, and through the cooperation of the differential 39, a certain speed difference can be formed between the spiral pusher 34 and the drum 33.

[0046] In some embodiments, a slag discharge pipe 6 and a liquid discharge pipe 61 are fixed to the bottom of the equipment frame 31 . The slag discharge pipe 6 is located at the bottom of the slag discharge port 35 , and the liquid discharge pipe 61 is located at the bottom of the overflow hole 36 .

[0047] It should be noted that before the dehydration treatment, the flanges at the bottom of the slag discharge pipe 6 and the liquid discharge pipe 61 can be respectively connected to the solid phase and liquid phase collection pipes, so that the solid phase discharged from the slag discharge port 35 can be discharged and collected through the slag discharge pipe 6 at the bottom of the equipment frame 31, and the liquid phase discharged from the overflow hole 36 can be discharged and collected through the liquid discharge pipe 61 at the bottom of the equipment frame 31.

[0048] like Figure 1 As shown, in some embodiments, the top of the pretreatment tank 1 is connected to a second doser 7 for quickly stirring and mixing reagents through a pipeline, and the inner bottom of the pretreatment tank 1 is provided with an agitator 8 for stirring the sludge inside the pretreatment tank 1.

[0049] It should be noted that the second doser 7 has the same structural shape as the first doser 53, and both have the function of rapidly stirring and mixing solids and liquids. When the pH value of the sludge in the pretreatment tank 1 is regulated, the agent can be first pre-mixed through the second doser 7, and then an acidic solution that can react quickly is added to the feed pipe 38 to increase the reaction rate; the specific structure of the agitator 8 is a mechanical mechanism that can form a rotating stirring in the pretreatment tank 1 in the prior art, and at least includes: a motor installed at the bottom of the pretreatment tank 1, and a stirring rod installed at the output end of the motor located inside the pretreatment tank 1; the stirring rod is driven to rotate by the motor, The sludge in the pretreatment tank 1 can be stirred so that the acidic solution added to the sludge can be evenly mixed with the sludge, thereby completing the pH value regulation; by using the acidic solution to regulate the pH value of the sludge, the acidic environment can promote the hydrolysis of polysaccharides and proteins in the microbial cell walls in the sludge, destroy the structure of the cell walls, reduce the cell wall's ability to adsorb water, and destroy the stability of the microbial cell walls and EPS in the sludge, thereby reducing the viscosity and water holding capacity of the sludge. Since the flocculant is more likely to combine with the partially depolymerized particles, it helps to provide a more flocculation environment for the flocculant in the subsequent flocculation treatment.

[0050] In some embodiments, the ultrasonic mechanism 2 includes: a plurality of Y-shaped processing tubes 21, a plurality of amplitude transformers 22 installed on the inner top of the plurality of Y-shaped processing tubes 21, and a plurality of ultrasonic transducers 23 installed on the outer end of the plurality of amplitude transformers 22 located on the Y-shaped processing tube 21; the input ends of the plurality of ultrasonic transducers 23 are electrically connected to an ultrasonic generator 24, and the plurality of Y-shaped processing tubes 21 are connected in series with each other.

[0051] It should be noted that the number of Y-shaped treatment tubes 21, horn 22 and ultrasonic transducers 23 is the same, preferably four; the sludge after the pH value is adjusted enters several Y-shaped treatment tubes 21 connected in series, and the sound waves are transmitted to several ultrasonic transducers 23 through the ultrasonic generator 24. The ultrasonic transducer 23 generates mechanical vibrations under the action of the electric field, and can transmit vibration signals to the horn 22. The horn 22 adjusts the stiffness by changing the shape of the structure or the internal mechanical properties, and can generate strong mechanical vibrations and pressure waves to the sludge in the Y-shaped treatment tube 21, so that the network structure of the microbial cell wall and EPS (extracellular polymer) in the sludge is destroyed, so that the tightly bound water can be released, and at the same time, a cavitation effect can be generated in the sludge, that is, tiny bubbles are formed in the liquid. The rapid formation and collapse of the bubbles can generate strong shear force, thereby further destroying the network structure in the sludge, releasing more free water and smaller particles, so that the particles are more easily aggregated into larger flocs under the subsequent flocculation effect, which helps to improve the efficiency of subsequent centrifugal dehydration.

[0052] In some embodiments, a feed pipe 9 is fixed to one side of the pretreatment tank 1, a first connecting pipe 91 is fixed between the pretreatment tank 1 and the Y-shaped treatment pipe 21, a second connecting pipe 92 is fixed between the Y-shaped treatment pipe 21 and the feed pipe 38, and plunger pumps are installed on the feed pipe 9, the Y-shaped treatment pipe 21 and the feed pipe 38.

[0053] It should be noted that by turning on the plunger pump on the feed pipe 9, the sludge to be treated can be passed into the interior of the pretreatment tank 1 through the feed pipe 9; through the first connecting pipe 91 between the pretreatment tank 1 and the Y-shaped treatment pipe 21, under the action of the plunger pump, the sludge treated in the pretreatment tank 1 can be passed into the interior of the Y-shaped treatment pipe 21; through the second connecting pipe 92 between the Y-shaped treatment pipe 21 and the feed pipe 38, under the action of the plunger pump, the sludge after ultrasonic treatment can be passed into the feed pipe 38 for further treatment.

[0054] Example 1

[0055] The original municipal sludge in the experiment has a pH value of 8.1, a moisture content of 95.5%, a black color, an organic matter content of 37%-41%, and a total mass of 1 t. The treatment steps are as follows:

[0056] S1, passing the sludge to be treated into the pretreatment tank 1, and adjusting the pH value of the sludge to 3 using sulfuric acid;

[0057] S2, the sludge after pH adjustment is treated by ultrasonic mechanism 2 at 27% ultrasonic power for 20 minutes, so as to destroy the microbial cell wall and the network structure of the extracellular polymer in the sludge by ultrasonic wave;

[0058] S3, passing the ultrasonically treated sludge into the feed pipe 38, during which polyacrylamide is added to the sludge through the drug introduction component, the amount of polyacrylamide is 2.41 kg / t, the addition flow rate is 45 kg / h, and the sludge is evenly distributed into the drum 33 through the feed port 37 by connecting the feed component;

[0059] S4. While the sludge is introduced into the feed pipe 38, the power source is used to drive the drum 33 to rotate at a high speed of 2200 r / min, and the screw pusher 34 is driven to rotate at a speed of 2100 r / min in the same direction as the drum 33, so that the sludge entering the drum 33 is evenly distributed, and the solid phase particles with a density greater than that of the liquid phase are settled on the inner wall of the drum 33 by centrifugal force, and the screw pusher 34 is used to push the solid phase to the slag discharge port 35 at the smaller diameter end of the drum 33 for discharge, and the separated liquid phase is discharged from the overflow hole 36 at the larger diameter end, thereby completing the sludge dehydration treatment.

[0060] Example 2

[0061] This embodiment is basically the same as Embodiment 1, except that step S1 uses sulfuric acid to adjust the pH value of the sludge to 3.4.

[0062] Example 3

[0063] This embodiment is basically the same as the embodiment 1, except that: step S2 is performed with an ultrasonic power of 27% for 10 minutes.

[0064] Comparative Example 1

[0065] This comparative example is basically the same as Example 1, except that: there is no step S1, and in step S2, the original sludge is passed into the ultrasonic mechanism 2.

[0066] Comparative Example 2

[0067] This comparative example is basically the same as Example 1, except that: step S1 uses sulfuric acid to adjust the pH value of the sludge to 4.3.

[0068] Comparative Example 3

[0069] This comparative example is basically the same as Example 1, except that there is no step S2, and in step S2, the sludge after pH value adjustment is passed into the feed pipe 38.

[0070] Comparative Example 4

[0071] This comparative example is basically the same as Example 1, except that: Step S3 specifically comprises: passing the ultrasonically treated sludge into the feed pipe 38 , and connecting the feed assembly so that the sludge is evenly distributed into the drum 33 through the feed port 37 .

[0072] Comparative Example 5

[0073] This comparative example is basically the same as Example 1, except that the amount of polyacrylamide used in step S3 is 3.52 kg / t.

[0074] Comparative Example 6

[0075] This comparative example is basically the same as Example 1, except that the addition rate of polyacrylamide in step S3 is 60 kg / h.

[0076] Test method: Under 0.1 MPa, vacuum filtration was performed to determine the moisture content of the solid sludge after dehydration treatment in Example 1 and Comparative Examples 1-3. The results are shown in Table 1.

[0077] Table 1

[0078]

[0079]

[0080] It can be seen from the experimental structure in Table 1 that in the dewatering treatment of municipal sludge in Examples 1-3, the pH value is adjusted to achieve a certain acidic condition before the sludge is treated, and ultrasonic treatment is used to destroy the microbial cell wall and the EPS network structure in the sludge. Then, a flocculant is used together with the sludge for centrifugal dewatering. The moisture content of the sludge obtained after treatment can be reduced to below 60%, so that it exhibits better dewatering performance.

[0081] By comparing Example 1 with Comparative Example 1, it can be seen that due to the alkaline conditions of the original sludge, the moisture content of the sludge after the acidic regulation of pH value is still relatively high, because after acidic regulation, the hydrolysis of polysaccharides and proteins in the cell walls of microorganisms in the sludge can be promoted, and the stability of its network structure can be reduced, so that the water in the sludge is more easily released, and because the flocculant is more likely to combine with the partially depolymerized particles, it provides an environment for the flocculant to be more easily flocculated, thereby improving the dehydration effect after dehydration treatment. By comparing Example 1 with Comparative Example 2, it can be seen that although the acidic regulation of the sludge is completed, some of the microorganisms present in the sludge have a certain acid resistance, and still maintain a certain activity under this acidic condition, and continue to produce EPS. EPS easily rebuilds the network structure of the sludge, increases the viscosity and water holding capacity of the sludge, and thus hinders the dehydration process.

[0082] By comparing Example 1 with Comparative Example 3, it can be learned that when the sludge after acidity control is not subjected to ultrasonic treatment, although the hydrolysis of polysaccharides and proteins in the cell walls of certain microorganisms in the sludge is promoted and the stability of its network structure is reduced, the released water is small and the particles are large, so it is difficult to improve the subsequent flocculation and dehydration effects. By subjecting the sludge to ultrasonic treatment, the mechanical effect and cavitation effect produced can further destroy the network structure in the sludge, promote the release of water, and release more free water and smaller particles, which are easier to aggregate into larger flocs under the subsequent flocculation effect, so as to achieve better dehydration effect.

[0083] By comparing Example 1 with Comparative Example 4, it can be seen that by using a flocculant and sludge together for centrifugal dehydration in the flocculation environment provided by acidic regulation and ultrasonic treatment, compared with no flocculation treatment, the former can react with organic matter in the sludge, and the tiny particles in the sludge are aggregated into larger flocs, forming flocs with better dehydration performance, thereby improving the sludge dehydration effect. By comparing Example 1 with Comparative Example 5, it can be seen that although the higher the content of the flocculant, the easier it is to achieve the effect of clear effluent and low sludge moisture content, but when the content is too high, even if the dosage rate is increased, it is difficult to achieve a good dehydration effect. By comparing Example 1 with Comparative Example 6, it can be seen that when the flocculant is added, when it is increased to a certain addition flow rate, it is easy to make the flocs it acts on larger and uneven in size. Although larger flocs theoretically have a faster sedimentation speed, if the flocs are too large, a layered structure will be formed in the drum 33, resulting in some flocs being unable to effectively contact the inner wall of the drum 33, thereby reducing the dehydration efficiency.

[0084] The above is based on the ideal embodiment of the present invention. Through the above description, it is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0085] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A municipal sludge treatment device, characterized in that: include: A pretreatment tank, an ultrasonic mechanism and a centrifugal dehydration mechanism that are interconnected; The pretreatment tank is used to control the pH value of the sludge before treatment, and the ultrasonic mechanism is used to change the internal structure of the sludge using ultrasonic waves; The centrifugal dehydration mechanism comprises: an equipment frame, a cover shell installed on the top of the equipment frame, and a drum rotatably connected to the equipment frame; a spiral pusher is rotatably connected to the inner side of the drum, a plurality of slag discharge ports are opened at the end with a smaller diameter of the drum, and a plurality of overflow holes are opened at the end with a larger diameter; A plurality of feed ports are provided on the side of the spiral propeller, and a feed pipe is rotatably connected to one end of the rotating drum located outside the cover shell. A connecting feed component for achieving uniform feeding into the rotating drum is provided between the feed pipe and the plurality of feed ports, and a drug introduction component for adding flocculant into the feed pipe is provided on the feed pipe. The equipment frame is provided with a plurality of power sources for respectively driving the rotating drum and the spiral propeller to rotate.

2. A municipal sludge treatment device according to claim 1, characterized in that: The connecting feed assembly includes: a connecting flow channel opened on the inner side of the spiral pusher, a material distribution cavity opened at one end of the connecting flow channel, and a V-shaped stopper fixed on the inner side of the material distribution cavity; the feed pipe is connected with the connecting flow channel, the material distribution cavity and several feed ports in sequence, and arc-shaped transition structures are arranged on both sides of the V-shaped stopper and the feed port.

3. A municipal sludge treatment device according to claim 1, characterized in that: The drug introducing assembly includes: an annular tube sleeved on the side of the feed pipe, a plurality of drug introducing heads fixed on the inner side of the annular tube, and a drug introducing tube fixed on the side of the annular tube; one end of the drug introducing tube is connected to a first drug doser for quickly stirring the mixed medicine through a pipeline, and one end of a plurality of the drug introducing heads penetrates into the inner side of the feed pipe.

4. A municipal sludge treatment device according to claim 1, characterized in that: A differential is installed at one end of the spiral pusher located outside the cover shell, and a plurality of power sources are respectively connected to one end of the drum located outside the cover shell and one end of the differential; a slag discharge pipe and a liquid discharge pipe are fixed to the bottom of the equipment frame, the slag discharge pipe is located at the bottom of the slag discharge port, and the liquid discharge pipe is located at the bottom of the overflow hole.

5. A municipal sludge treatment device according to claim 1, characterized in that: The top of the pretreatment tank is connected to a second doser for rapidly stirring and mixing the reagents through a pipeline, and the inner bottom of the pretreatment tank is provided with a stirrer for stirring the sludge inside the pretreatment tank.

6. A municipal sludge treatment device according to claim 1, characterized in that: The ultrasonic mechanism includes: a plurality of Y-shaped processing tubes, a plurality of amplitude rods installed on the inner top of the plurality of Y-shaped processing tubes, and a plurality of ultrasonic transducers installed on one end of the plurality of amplitude rods located on the outer side of the Y-shaped processing tubes; the input ends of the plurality of ultrasonic transducers are electrically connected to an ultrasonic generator, and the plurality of Y-shaped processing tubes are connected in series with each other.

7. A municipal sludge treatment device according to claim 6, characterized in that: A feed pipe is fixed on one side of the pretreatment tank, a first connecting pipe is fixed between the pretreatment tank and the Y-shaped treatment pipe, a second connecting pipe is fixed between the Y-shaped treatment pipe and the feed pipe, and plunger pumps are installed on the feed pipe, the Y-shaped treatment pipe and the feed pipe.

8. A treatment method for a municipal sludge treatment device according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Pass the sludge to be treated into the pretreatment tank and use an acidic solution to adjust the pH value of the sludge; S2, passing the pH-adjusted sludge through an ultrasonic device to destroy the microbial cell walls and the network structure of the extracellular polymers in the sludge by using ultrasonic waves; S3, passing the ultrasonically treated sludge into the feed pipe, during which the sludge is passed into the feed pipe, adding flocculant to the sludge through the drug introduction component, and connecting the feed component so that the sludge is evenly distributed into the drum through the feed port; S4. While introducing sludge into the feed pipe, the power source drives the drum and the screw pusher to rotate in the same direction, so that the sludge entering the drum is evenly distributed. The solid particles with a density greater than that of the liquid phase are settled on the inner wall of the drum by centrifugal force. The screw pusher is used to push the solid phase to the discharge port at the smaller diameter end of the drum for discharge, and the separated liquid phase is discharged from the overflow hole at the larger diameter end, thereby completing the sludge dehydration process.

9. The method for treating a municipal sludge treatment device according to claim 8, characterized in that: In the step S1, the acidic solution is one of sulfuric acid or hydrochloric acid, and the pH value of the sludge is 2.9-3.5; in the step S2, the ultrasonic power of the ultrasonic mechanism is 20-30%, and the processing time is 10-30 minutes; in the step S3, the flocculant is one of polyacrylamide or polyaluminum chloride, the amount of the flocculant in the sludge is 2.2-2.8 kg / t, and the addition flow rate of the flocculant is 44-56 kg / h.

10. The method for treating a municipal sludge treatment device according to claim 8, characterized in that: In the step S4, the rotation speed of the drum is 2000-2300 r / min, and the rotation speed of the spiral pusher is slightly lower than the rotation speed of the drum.

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