High-pressure shearing treatment method for urban domestic sludge floc structure

Abstract

The invention relates to the technical field of sludge floc treatment, and discloses an urban domestic sludge floc structure high-pressure shearing treatment method which comprises the following steps: communicating a treatment box body provided with a mechanical device for generating high pressure with a sludge conveying pipeline; the sludge conveying pipeline is used for conveying sludge into the treatment box body; a mechanical device is started, so that alternating pressure of 0-16 MPa is generated in the treatment box body, and mechanical treatment of repeatedly applying high pressure to the sludge and instantly releasing the pressure is performed; a plurality of groups of slit structures are mounted in the sludge conveying pipeline, and the sludge is conveyed into the plurality of groups of slit structures by alternating pressure to be subjected to multi-stage reciprocating extrusion, cutting and friction; and the sludge conveying pipeline is used for conveying the treated sludge into the filter pressing dehydrator for dehydration treatment. After the steps are adopted, the method has the following advantages that separation of most of cell water and urban domestic sludge flocs is improved, preparation is made for subsequent deep dehydration of the urban domestic sludge, and the purpose of improving the dehydration efficiency of the urban domestic sludge is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of sludge floc treatment, in particular to a high-pressure shearing treatment method for urban domestic sludge floc structure. Background Art

[0002] As a hydrophilic flocculent organic matter, the colloidal network structure of municipal sludge is very loose, with many pores and obvious pore size. The surface of the sludge is uneven, and there are a small amount of branched structures and fibers of crystal growth, showing a multi-hole flocculent structure with strong water holding capacity. Municipal sludge is a complex mixture mainly composed of organic components, consisting of soluble organic matter and insoluble inorganic matter. After the initial dehydration, the sludge produced by a general sewage treatment plant generally has a water content of about 80% to 90%, containing solid or semi-solid substances, of which the main solid components are organic debris, bacterial cells, inorganic particles, colloids and all flocculation solvents. At present, domestic and foreign research has also divided the sludge composition into cells, extracellular polymers and some inorganic inert substances.

[0003] As for the floc structure of activated sludge, it can be clearly seen that activated sludge is mainly composed of a large number of microorganisms and organic matter, and bacteria live together in groups. Spherical bacteria are the main bacterial groups. In addition to microorganisms, other substances such as extracellular polymers, organic matter, inorganic salts, etc. are scattered around the bacteria, and together with bacteria, fungi, etc., they constitute the activated sludge visible to the naked eye in the sewage treatment plant. The bacteria are spherical and rod-shaped, gathered together in groups, and the surface structure is complete. The formation of the floc structure of activated sludge goes through four stages, namely bacterial proliferation, floc formation, floc aggregation and floc structure formation. A large number of proliferated bacteria gradually attach to the sludge particles and form bacterial flocs. The sludge gradually condenses to form small flocs. The color of the sludge changes from light gray to earthy yellow in appearance. Finally, the small flocs further condense to form a larger and densely structured floc structure. Therefore, the number and richness of bacteria also directly determine the efficiency of sewage treatment.

[0004] At present, the main method of dewatering urban domestic sludge in my country is mechanical dewatering. The widely used mechanical dewatering equipment includes belt filter press, plate and frame filter press, centrifugal filter press, etc. These dewatering equipment are limited by defects such as low filtration pressure and low filtration efficiency. It is difficult to reduce the moisture content of the dehydrated sludge to below 60%, which brings difficulties to subsequent treatment and disposal.

[0005] Therefore, it is urgent to further improve the dewatering efficiency of residual sludge and implement deep dehydration to further reduce the moisture content of the treated sludge in order to achieve large-scale reduction.

[0006] In view of the above problems, the present invention proposes a high-pressure shearing treatment method for floc structure of urban domestic sludge to solve the problem of low sewage treatment efficiency due to high water content of dehydrated sludge. Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] The present invention aims to solve the problem of low sewage treatment efficiency due to high water content of dehydrated sludge.

[0009] (II) Technical solution

[0010] In order to solve the above technical problems, the present invention provides a technical solution: a high-pressure shearing treatment method for floc structure of urban domestic sludge, comprising the following steps:

[0011] (1) connecting a treatment box equipped with a mechanical device for generating high pressure to a sludge conveying pipeline;

[0012] (2) The sludge conveying pipeline conveys the sludge into the treatment box;

[0013] (3) Starting the mechanical device to generate an alternating pressure of 0 to 16 MPa inside the treatment box, repeatedly applying high pressure and instantaneous pressure relief to the sludge;

[0014] (4) Multiple slit structures are installed inside the sludge conveying pipeline, and alternating pressure conveys the sludge to the multiple slit structures for multi-stage reciprocating extrusion, cutting and friction;

[0015] (5) The sludge conveying pipeline conveys the treated sludge to the filter press dewatering machine, where the sludge is dehydrated.

[0016] As an improvement, the slit structure described in step (4) overcomes the repulsive force between the intracellular and extracellular polymers of the microorganisms in the sludge, and the polymers inside and outside the sludge and the microbial cell structure are continuously destroyed. The energy input brought by the alternating pressure described in step (3) opens the chemical bonds between the sludge flocs and water molecules, destroys the floc structure and organization, and breaks the walls of some biomass cells.

[0017] As an improvement, the filter press dehydrator in step (5) can be a belt filter press, a plate and frame filter press or a centrifugal filter press.

[0018] After adopting the above steps, the present invention has the following advantages: through the multi-stage extrusion, cutting and friction of the mud body by the slit, the repulsive force between the intracellular and extracellular polymers of the microorganism is overcome, the polymers inside and outside the sludge and the microbial cell structure are continuously destroyed, and the energy input brought by the alternating pressure increases the probability of opening the chemical bonds between the sludge flocs and the water molecules, and aggravates the destruction of the floc structure organization and the wall breaking of some biomass cells, wherein the organic matter dissolution effect is enhanced, thereby breaking the confinement of the water molecules by the flocculent agglomerates of the urban domestic sludge, and finally releasing the internal water in the microbial cells and the surface water and interstitial water between the sludge flocs to become free water, therefore, finally improving the separation of most of the cell water and the urban domestic sludge flocs, preparing for the subsequent deep dehydration of the urban domestic sludge, and facilitating the analysis of the water inside the sludge, thereby achieving the purpose of improving the dehydration efficiency of the urban domestic sludge. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the distribution of water forms in the sludge of the present invention.

[0020] Figure 2 It is a schematic diagram of the sludge floc structure of the present invention.

[0021] Figure 3 It is a schematic diagram of the method for crushing active cells in municipal sewage sludge of the present invention. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] A high-pressure shearing treatment method for flocculent structure of municipal sewage sludge comprises the following steps:

[0024] (1) connecting a treatment box equipped with a mechanical device for generating high pressure to a sludge conveying pipeline;

[0025] (2) The sludge conveying pipeline conveys the sludge into the treatment box;

[0026] (3) The mechanical device is started to generate an alternating pressure of 0 to 16 MPa inside the treatment box, and the sludge is repeatedly subjected to mechanical treatment of high pressure and instantaneous pressure relief. When a pressure of 16 MPa is generated inside the treatment box, the sludge is squeezed into the sludge conveying pipeline. When the pressure inside the treatment box is instantly reduced from 16 MPa to 0 MPa, the sludge flows in the reverse direction inside the sludge conveying pipeline.

[0027] (4) A plurality of slit structures are installed inside the sludge conveying pipeline, and the alternating pressure conveys the sludge to the plurality of slit structures for multi-stage reciprocating extrusion, cutting and friction. The slit structures overcome the repulsive force between the intracellular and extracellular polymers of the microorganisms in the sludge, and the polymers inside and outside the sludge and the microbial cell structure are continuously destroyed. The energy input brought by the alternating pressure in step (3) opens the chemical bonds between the sludge flocs and the water molecules, destroys the floc structure and breaks the walls of some biomass cells.

[0028] (5) The sludge conveying pipeline delivers the treated sludge to the filter press dehydrator. The sludge can be dehydrated by various filter press dehydrators such as belt filter press, plate and frame filter press or centrifugal filter press. The moisture content of the sludge after filter pressing is reduced to below 60%.

[0029] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0030] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0031] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A method for high-pressure shearing treatment of floc structure of municipal sewage sludge, characterized in that: The following steps are involved: (1) connecting a treatment box equipped with a mechanical device for generating high pressure to a sludge conveying pipeline; (2) The sludge conveying pipeline conveys the sludge into the treatment box; (3) Starting the mechanical device to generate an alternating pressure of 0 to 16 MPa inside the treatment box, repeatedly applying high pressure and instantaneous pressure relief to the sludge; (4) Multiple slit structures are installed inside the sludge conveying pipeline, and alternating pressure conveys the sludge to the multiple slit structures for multi-stage reciprocating extrusion, cutting and friction; (5) The sludge conveying pipeline conveys the treated sludge to the filter press dewatering machine, where the sludge is dehydrated.

2. A method for high pressure shearing treatment of floc structure of municipal sewage sludge according to claim 1, characterized in that: The slit structure described in step (4) overcomes the repulsive force between the intracellular and extracellular polymers of the microorganisms in the sludge, and the polymers inside and outside the sludge and the microbial cell structure are continuously destroyed. The energy input brought by the alternating pressure described in step (3) opens the chemical bonds between the sludge flocs and water molecules, destroys the floc structure and breaks the walls of some biomass cells.

3. A method for high pressure shearing treatment of floc structure of municipal sewage sludge according to claim 1, characterized in that: The filter press dehydrator in step (5) can be a belt filter press, a plate and frame filter press or a centrifugal filter press.

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