Coal ethylene glycol wastewater zero discharge treatment equipment and treatment method thereof

Abstract

The invention discloses coal ethylene glycol wastewater zero discharge treatment equipment and a treatment method thereof, and relates to the technical field of wastewater treatment.The coal ethylene glycol wastewater zero discharge treatment equipment comprises a reaction tank body, and a sewage distribution assembly, a circular reaction assembly and a three-phase separation assembly are sequentially arranged in the reaction tank body from bottom to top; the circular reaction assembly is arranged in a sludge reaction area in the middle of the tank body, the circular reaction assembly comprises a flow guide cover which is vertically arranged and a main shaft which is coaxially arranged with the flow guide cover, and a sludge particle size regulation and control system which is controlled by the main shaft to operate is arranged in the flow guide cover; the three-phase separation assembly is arranged at the top of the reaction tank body. According to the present invention, the returned sludge is subjected to mechanical homogenization in-situ treatment, such that the easily lost small flocs are polymerized, the easily inerted large particles are crushed, and the sludge population is actively maintained in the optimal particle size interval so as to overcome the sludge particle size polarization problem caused by the natural selection of the traditional reactor; and a fundamental guarantee is provided for maintaining a high-concentration and high-activity sludge bed layer.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wastewater treatment, in particular to a coal-to-ethylene glycol wastewater zero discharge treatment equipment and a treatment method thereof. BACKGROUND

[0002] Anaerobic ammonia oxidation (ANAMMOX) process, as a new type of high-efficiency and energy-saving biological denitrification technology, has shown great potential in the field of treating coal-to-ethylene glycol wastewater with high ammonia-nitrogen. The process is usually carried out in an upflow anaerobic sludge bed (UASB) reactor, and its efficiency core relies on the high-concentration, high-activity and good-settling-performance anaerobic ammonia oxidation bacteria (AAOB) granular sludge in the reactor.

[0003] The UASB reactor forms an upward flow by water distribution at the bottom and realizes gas, liquid and solid separation and sludge reflux by a three-phase separator at the top. However, the bottleneck of the existing technology is exactly this basic working principle: first, the bubbles produced by the reaction merge and stir during the upward process, and after entering the three-phase separation zone, the sludge in the reactor is often difficult to be in a granular homogenization state. In addition to the granular sludge with a particle size in the optimal interval, the sludge system also contains small-particle-size discrete sludge and large-particle-size agglomerated sludge. During the downward reflux of the sludge, the discrete sludge with lighter specific gravity is difficult to settle and reflux quickly, but is carried out by the water flow or distributed disorderly in the whole reaction zone, causing the loss of active sludge; second, for the larger sludge particles that have been flocculated into agglomerates, the stirring action of the bubbles is not enough to break their cohesive structure, causing these large particles to quickly settle at the bottom, but their inner cores are often hollow due to mass transfer obstruction, resulting in the death of anaerobic ammonia oxidation bacteria and a significant reduction in activity.

[0004] The contradictory phenomena of "easy loss of discrete sludge" and "easy inertization of large granular sludge" cause the reactor to be difficult to maintain a sludge bed layer with uniform particle size distribution and stable activity for a long time. The direct consequence is insufficient effective concentration of sludge and shortened residence time, ultimately resulting in decreased denitrification efficiency and unstable operation of the system. The existing improvements focus on optimizing the structure of the three-phase separator to improve the separation efficiency, but they cannot fundamentally solve the optimization problem of the properties of the sludge particles themselves, and cannot break out of the paradigm of "passive separation". SUMMARY

[0005] The purpose of the present application is to solve the problem that the existing technology is difficult to maintain a sludge bed layer with uniform particle size distribution and stable activity for a long time, resulting in insufficient effective concentration of sludge and shortened residence time, and to provide a coal-to-ethylene glycol wastewater zero discharge treatment equipment and a treatment method thereof.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0007] Coal-to-ethylene glycol wastewater zero discharge treatment equipment, comprising a reaction tank body, sequentially arranged from bottom to top in the reaction tank body are:

[0008] Sewage distribution assembly, which is arranged at the bottom of the reaction tank body, is used to introduce wastewater and stir the bottom sludge to form an upward flow;

[0009] Circulating reaction assembly, which is arranged in the sludge reaction zone of the middle part of the tank body, comprises a vertically arranged flow guide cover and a main shaft coaxially arranged with the flow guide cover, the main shaft is driven by a motor mounted at the bottom of the reaction tank body, the flow guide cover is provided with a sludge particle size regulation system controlled by the main shaft, and the sludge particle size regulation system is arranged to be capable of regulating the backflow sludge in situ to make the particle size distribution of the sludge particles tend to be uniform;

[0010] Three-phase separation assembly, which is arranged at the top of the reaction tank body, is used to realize three-phase separation of gas, liquid and solid;

[0011] The flow guide cover separates the sludge reaction zone into an internal downward flow zone and an external upward flow zone, the backflow sludge separated by the three-phase separation assembly is guided to the top of the downward flow zone and discharged from the bottom of the flow guide cover to the upward flow zone after being treated by the sludge particle size regulation system.

[0012] Preferably, the sludge particle size regulation system comprises:

[0013] A crushing mechanism for crushing large-diameter agglomerated sludge particles;

[0014] An aggregation mechanism for promoting the aggregation of discrete small-diameter sludge flocs;

[0015] A flow guide mechanism for forming an axial circulating flow field in the circulating reaction assembly;

[0016] The crushing mechanism, the aggregation mechanism and the flow guide mechanism are arranged in the flow guide cover from top to bottom, and the main shaft penetrates through the flow guide cover and drives the mechanisms to operate synchronously.

[0017] Preferably, a sleeve is sleeved on the main shaft, and a speed reduction transmission structure is arranged between the main shaft and the sleeve, so that when the main shaft rotates, the sleeve can rotate at a different speed;

[0018] The crushing mechanism and the aggregation mechanism are mounted on the sleeve and driven by the sleeve, and the flow guide mechanism is mounted on the main shaft and directly driven by the main shaft.

[0019] Preferably, the speed reduction transmission structure comprises support frames fixedly installed on the upper and lower ends of the sleeve, and at least three interval gears are rotatably installed on the support frames;

[0020] An outer gear ring is fixedly installed on the outer wall of the main shaft and engages with the spacer gear;

[0021] An inner gear ring is fixedly installed on the inner wall of the rotating sleeve and engages with the spacer gear;

[0022] The gear ratio of the outer gear ring, the spacer gear and the inner gear ring controls the speed reduction ratio of the rotating sleeve relative to the main shaft.

[0023] Preferably, the flow guide cover is composed of multiple coaxially spliced variable-diameter sleeves;

[0024] Each variable-diameter sleeve has a wide-diameter part and a narrow-diameter part;

[0025] The narrow-diameter part of a lower variable-diameter sleeve is inserted into the wide-diameter part of an adjacent upper variable-diameter sleeve and is fixed by armature welding. An annular overflow gap is formed between the outer wall of the narrow-diameter part of the lower variable-diameter sleeve and the inner wall of the wide-diameter part of the upper variable-diameter sleeve;

[0026] The sludge particles whose particle size has been optimized by the sludge particle size control system are thrown to the inner wall of the variable-diameter sleeve under the action of centrifugal force and are discharged to the upward flow area outside the flow guide cover through the overflow gap under the action of gravity.

[0027] Preferably, the crushing mechanism includes a fixed knife group radially installed on the inner wall of the top variable-diameter sleeve and a moving knife group radially installed on the outer wall of the rotating sleeve. The fixed knife group and the moving knife group are alternately arranged in the vertical direction.

[0028] Preferably, the aggregation mechanism includes:

[0029] Multiple elastic frame plates have their inner ends fixedly installed on the rotating sleeve;

[0030] A grid-type trapping net is installed on the elastic frame plate for trapping small sludge flocs;

[0031] In a natural state, the outer end of the elastic frame plate exceeds the variable-diameter sleeve, so that the elastic frame plate is in a curved state after being installed in the variable-diameter sleeve and continuously abuts against the inner wall of the variable-diameter sleeve with its outer end;

[0032] At least one wedge-shaped protrusion is provided on the inner wall of the variable-diameter sleeve;

[0033] Rollers are installed on the outer end of the elastic frame plate and rollingly contact the inner wall of the variable-diameter sleeve.

[0034] Preferably, the flow guide mechanism is an axial flow impeller installed on the main shaft and generates an axial thrust from top to bottom in the flow guide cover when rotating, thereby forming an internal circulation flow path opposite to the direction of the external upward flow.

[0035] Preferably, the three-phase separation assembly comprises a plurality of concentrically arranged blocking rings, the cross section of the blocking rings is L-shaped with unequal width, a triangular interception gas chamber is formed below each of the blocking rings, the long plate surface of the blocking ring is close to the center of the reaction tank body and extends to the lower end of the short plate surface of the adjacent blocking ring, a sludge backflow gap is formed between the adjacent two blocking rings, a plurality of gas guide pipes are connected and supported between the plurality of blocking rings, and the gas guide pipes are in communication with the interception gas chamber;

[0036] The center of the blocking ring has a reverse conical precipitation cover coaxial with the flow guide cover, an overflow weir is arranged above the blocking ring and fixed to the inner wall of the reaction tank body, a water outlet area is formed between the overflow weir and the inner wall of the reaction tank body, the top of the overflow weir exceeds the precipitation cover and is provided with a water blocking ring extending into the precipitation cover and having a water flow channel with the precipitation cover, and a plurality of coaxially arranged annular inclined plates are arranged in the water flow channel.

[0037] The treatment method of the coal-to-ethylene glycol wastewater zero discharge treatment equipment comprises the following steps:

[0038] S1: The pretreated coal-to-ethylene glycol wastewater is introduced into the bottom of the reaction tank body through the sewage distribution assembly, the water distribution process causes the sludge at the bottom to form an upward flow, so that the wastewater and the activated sludge are fully mixed and enter the sludge reaction zone;

[0039] S2: The motor is started to drive the main shaft to rotate, thereby driving the sludge particle size control system to operate;

[0040] An axial flow field is formed inside the flow guide cover from top to bottom through the flow guide mechanism, and the sludge-water mixture is forced to flow downward in the downward flow zone;

[0041] After the mixture in the downward flow zone is discharged from the bottom of the flow guide cover, it moves upward in the upward flow zone outside the flow guide cover, thereby forming a continuous internal and external circulation flow between the inside and the outside of the flow guide cover;

[0042] The large-particle-size sludge clumps are mechanically sheared and broken in the circulation flow through the breaking mechanism, so that they are broken into medium-particle-size particles;

[0043] Small-particle-size sludge flocs are captured and intercepted in the circulation flow through the aggregation mechanism, and mutual collision and aggregation are promoted to form medium-particle-size particles;

[0044] S3: The activated sludge with uniform particle size after step S2 is fully subjected to anammox reaction with ammonia nitrogen and nitrite nitrogen in the wastewater in the upward flow zone;

[0045] S4: The gas-liquid-solid mixture after the reaction rises to the three-phase separation assembly;

[0046] The gas is intercepted in the interception gas chamber and is collected and discharged through the gas guide pipe;

[0047] Part of the solid sludge settles along the sludge backflow gap between the blocking rings, is collected through the precipitation cover, and is then redirected to the inlet of the downflow area at the top of the flow guide cover to achieve sludge backflow;

[0048] The separated clear liquid and part of the fine suspended matter that fails to settle enter the clean water outlet channel formed by the water blocking ring and the inner wall of the precipitation cover, flow through the surface of the annular inclined plate, the fine suspended matter settles and slides back to the reaction area on the surface of the annular inclined plate, and the treated supernatant is overflowed through the overflow weir;

[0049] S5: The treated water discharged from the overflow weir enters the subsequent deep treatment and zero discharge section until it meets the standard.

[0050] Compared with the prior art, the present application has the following advantages:

[0051] 1. The present application uses the built-in sludge particle size control system to perform in-situ treatment on the backflow sludge in the reaction area through mechanical homogenization, aggregates small flocs that are prone to loss, breaks large particles that are prone to inactivation, and actively maintains the sludge population in an optimal particle size range, thereby overcoming the problem of two-pole differentiation of sludge particle size caused by natural selection in traditional reactors and providing a fundamental guarantee for maintaining a high-concentration and high-activity sludge bed.

[0052] 2. The particle size of the homogenized sludge is moderate, which effectively avoids the problems of blocked internal core mass transfer and bacterial population decline caused by excessively large particle size, and the bacterial population can fully contact the substrate (ammonia nitrogen and nitrite), so that the denitrification activity of unit biomass is maximized, thereby greatly improving the volume load and total nitrogen removal efficiency of the reactor.

[0053] 3. The present application forms an internal circulating flow field opposite to the external upflow in the middle of the reactor through the flow guide cover and the internal flow guide mechanism, so that the backflow sludge flows along a predetermined path (downflow area) and is free from direct impact of the upflow and bubbles, thereby realizing rapid and stable backflow of the sludge to the bottom of the reactor and greatly reducing the risk of loss of activated sludge. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 A cross-sectional structure schematic diagram of the coal-to-ethylene glycol wastewater zero discharge treatment equipment according to the present application;

[0055] Figure 2 A whole structure schematic diagram of the coal-to-ethylene glycol wastewater zero discharge treatment equipment according to the present application;

[0056] Figure 3 A structure schematic diagram of the flow guide cover in the coal-to-ethylene glycol wastewater zero discharge treatment equipment according to the present application;

[0057] Figure 4 This is a cross-sectional schematic diagram of the guide hood in the zero-discharge treatment equipment for coal-to-ethylene glycol wastewater proposed in this invention;

[0058] Figure 5 This is a schematic diagram of the crushing and polymerization mechanisms in the zero-discharge treatment equipment for coal-to-ethylene glycol wastewater proposed in this invention.

[0059] Figure 6 This is a schematic diagram of the flow guiding mechanism in the zero-discharge treatment equipment for coal-to-ethylene glycol wastewater proposed in this invention;

[0060] Figure 7 This is a schematic diagram of the speed reduction transmission structure in the zero-discharge treatment equipment for coal-to-ethylene glycol wastewater proposed in this invention.

[0061] Figure 8 This is a schematic diagram showing the positional relationship between the elastic frame plate and the wedge-shaped protrusion in the zero-discharge treatment equipment for coal-to-ethylene glycol wastewater proposed in this invention.

[0062] Figure 9 for Figure 1 A magnified structural diagram of part A in the middle.

[0063] In the diagram: 1. Reaction tank body; 2. Wastewater distribution assembly; 21. Distribution pipe; 22. Wastewater inlet pipe; 23. Placement tank; 3. Circulation reaction assembly; 31. Main shaft; 32. Crushing mechanism; 321. Fixed blade assembly; 322. Moving blade assembly; 33. Aggregation mechanism; 331. Elastic frame plate; 332. Grille-type collection net; 333. Roller; 34. Flow guiding mechanism; 35. Flow guide hood; 351. Variable diameter sleeve; 351a. Wide diameter section; 35 1b. Narrow diameter section; 352. Overflow gap; 353. Wedge-shaped protrusion; 36. Rotating sleeve; 37. Speed ​​reduction transmission structure; 371. Support frame; 372. Spacer gear; 373. External gear ring; 374. Internal gear ring; 4. Three-phase separation assembly; 41. Barrier ring; 411. Sludge return gap; 412. Intercepting air chamber; 42. Air guide pipe; 43. Sedimentation hood; 44. Overflow weir; 45. Water-blocking ring; 46. Annular inclined plate; 5. Motor. Detailed Implementation

[0064] In existing technologies, upflow anaerobic sludge bed reactors form an upward flow by bottom water distribution and use a three-phase separator to achieve gas-liquid-solid separation and sludge recirculation. However, the sludge particle size distribution in the reactor is uneven, and discrete sludge is easily carried out of the system by the water flow. Large sludge particles have reduced activity due to internal mass transfer obstruction. Traditional improvement schemes focus on optimizing the separator structure, but have failed to break through the passive separation mode and cannot solve the problem of sludge deterioration.

[0065] Reference Figures 1-6This application proposes a zero-discharge treatment device for coal-to-ethylene glycol wastewater, including a reaction tank body 1, and a wastewater distribution component 2, a circulating reaction component 3 and a three-phase separation component 4 arranged sequentially from bottom to top inside the reaction tank body 1.

[0066] The circulating reaction assembly 3 includes a vertically arranged flow guide 35 and a main shaft 31 coaxially arranged with the flow guide 35. The main shaft 31 is driven by a motor 5 installed at the bottom of the reaction vessel body 1.

[0067] The flow guide shroud 35 is equipped with a sludge particle size control system driven by the main shaft 31.

[0068] The flow guide hood 35 divides the sludge reaction zone into an internal downward flow zone and an external upward flow zone, providing an independent space for sludge recycling. The return sludge separated by the three-phase separation component 4 enters the upward flow zone after being processed by the particle size control system.

[0069] The sludge particle size control system refers to a dynamic treatment unit that integrates mechanical crushing and flocculation functions. This unit simultaneously completes the crushing of large particles and the aggregation of small flocs during the sludge descent process, thereby achieving particle size homogenization.

[0070] Reference Figures 1-2 The wastewater distribution assembly 2 refers to the water distribution device installed at the bottom of the tank. Specifically, it can be a water distribution pipe 21 evenly distributed according to the bottom contour of the reaction tank 1. The water distribution pipe 21 is connected to the same wastewater inlet pipe 22. A placement trough 23 adapted to the water distribution pipe 21 is set at the bottom of the reaction tank 1. The placement trough 23 has a U-shaped cross-section. The outlet of the water distribution pipe 21 is set vertically downward and faces the bottom of the placement trough 23. The sludge accumulated at the bottom of the reaction tank 1 will cover the water distribution pipe 21 and be output downward through the water distribution pipe 21, so that the inlet water impacts the placement trough 23. By controlling the inlet water speed, the sludge at the bottom is agitated to form an upward flow. This assembly ensures that the wastewater and activated sludge are fully mixed and contacted. A sludge discharge pipe is also installed at the bottom of the reaction tank 1 for replacing the sludge bed.

[0071] The sludge particle size control system includes a crushing mechanism 32, a polymerization mechanism 33, and a flow guiding mechanism 34. The crushing mechanism 32 is used to crush large-diameter agglomerated sludge particles, the polymerization mechanism 33 is used to promote the polymerization of discrete small-diameter sludge flocs, and the flow guiding mechanism 34 is used to form an axial circulating flow field within the circulating reaction assembly 3. The crushing mechanism 32, polymerization mechanism 33, and flow guiding mechanism 34 are arranged from top to bottom inside the flow guiding hood 35, and the main shaft 31 passes through the flow guiding hood 35 and drives the various mechanisms to operate synchronously.

[0072] The three-phase separation component 4 is located at the top of the reaction tank 1 and is used to achieve gas, liquid and solid three-phase separation and to directionally transport the return sludge to the inlet of the descending flow zone.

[0073] Specifically, wastewater enters the reaction tank through the bottom water distribution assembly and mixes with the bottom sludge to form an upward flow. The main shaft 31 drives the sludge particle size control system inside the guide hood 35, creating a downward axial flow field in the descending flow zone. During the descent of the returned sludge, large particles are broken down by the crushing mechanism 32, while small flocs are captured and bound by the aggregation mechanism 33. The treated sludge enters the upward flow zone through the bottom of the guide hood 35 and continues to participate in the reaction during the circulating flow. The three-phase separation assembly 4 separates the reaction products: gas is discharged, sludge is returned, and the clarified liquid enters subsequent treatment. This circulating treatment mechanism keeps the sludge particles in a dynamically optimized state, preventing both the loss of small particles and the deposition of large particles.

[0074] Compared to existing technologies, traditional solutions rely on passive separation and cannot actively control sludge particle size. This solution, however, constructs internal and external circulation paths using a flow guide hood 35, embedding an active control system within the sludge return path. In existing technologies, sludge return relies solely on natural sedimentation; this solution uses mechanical drive to create a forced circulation flow field, enabling sludge particle size optimization during directional flow. Traditional three-phase separators only achieve physical separation; this solution combines the separation process with particle size control, forming a closed-loop treatment system.

[0075] Through the above technical solution, this application effectively solves the problems of activity loss and inertization caused by uneven sludge particle size distribution. Sludge particles are continuously homogenized during the recycling process, maintaining the stability and reactivity of the sludge bed. The synergistic effect of upflow and downflow prolongs the sludge residence time and enhances the denitrification reaction efficiency. The directionally transported return sludge, after particle size optimization, achieves efficient contact and reaction with pollutants in the upflow zone, ensuring the long-term stability of the system.

[0076] Reference Figures 1-6 This application further proposes that a rotating sleeve 36 is sleeved on the main shaft 31, and a speed reduction transmission structure 37 is provided between the main shaft 31 and the rotating sleeve 36, so that the rotating sleeve 36 can rotate at different speeds when the main shaft 31 rotates; the crushing mechanism 32 and the agglomeration mechanism 33 are installed on the rotating sleeve 36 and driven by it, and the flow guiding mechanism 34 is installed on the main shaft 31 and directly driven by it.

[0077] Among them, the rotating sleeve 36 refers to the rotatable component sleeved outside the main shaft 31. It forms a speed difference with the main shaft 31 through the speed reduction transmission structure 37, and is used to support the crushing mechanism 32 and the agglomeration mechanism 33 and transmit power.

[0078] Specifically, when the main shaft 31 rotates at high speed under the drive of the motor, the power is transmitted to the rotating sleeve 36 through the speed reduction transmission structure 37, causing it to rotate at a lower speed than the main shaft 31. The crushing mechanism 32 and the agglomeration mechanism 33 rotate synchronously with the rotating sleeve 36, completing the sludge crushing and floc agglomeration operations at a lower speed, avoiding excessive damage to the sludge structure caused by high-speed rotation. At the same time, the main shaft 31 directly drives the flow guiding mechanism 34 to operate at high speed at its original speed, generating sufficient axial thrust to maintain the strength of the circulating flow field inside the flow guide shroud 35. Thus, the fine mechanical action required for crushing and agglomeration functions and the high kinetic energy output required for flow guiding functions are simultaneously satisfied, and the synergistic optimization of different process links is achieved through the differentiated allocation of rotational speeds.

[0079] The flow guiding mechanism 34 requires high rotational speed to maintain the flow field intensity, but the high-speed rotating crushing mechanism 32 will excessively shear the sludge flocs, while the high-speed operating agglomeration mechanism 33 will result in excessive radial flow, failing to effectively promote floc collision. This solution achieves differential drive through a speed reduction transmission structure 37, allowing the flow guiding mechanism 34 to maintain high rotational speed to enhance the circulating flow field, while enabling the crushing and agglomeration mechanisms 33 to operate with precision at low rotational speeds, fundamentally resolving the contradiction in the rotational speed requirements of multiple mechanisms.

[0080] Reference Figures 3-7 This application further proposes a speed reduction transmission structure 37 including a support frame 371 fixedly installed at the upper and lower ends of the rotating sleeve 36. The support frame 371 is a rigid frame used to fix the rotating sleeve 36 and bear the transmission components. At least three spaced gears 372 are rotatably installed on the support frame 371. The spaced gears 372 are transmission gears that are evenly distributed around the circumference of the support frame 371. The symmetrical distribution of three or more gears can balance the transmission torque and avoid wear caused by single-point force.

[0081] An external gear ring 373 is fixedly installed on the outer wall of the main shaft 31, which meshes with the spacer gear 372; an internal gear ring 374 is fixedly installed on the inner wall of the rotating sleeve 36, which meshes with the spacer gear 372; the reduction ratio of the rotating sleeve 36 relative to the main shaft 31 is controlled by the ratio of the number of teeth of the external gear ring 373, the spacer gear 372 and the internal gear ring 374.

[0082] The external gear ring 373 transmits power from the main shaft 31 to the rotating sleeve 36 through meshing with the spacer gear 372, while the internal gear ring 374 forms a reduction output end through meshing with the spacer gear 372. The gear ratio refers to the proportional relationship between the number of teeth of the external gear ring 373, the spacer gear 372, and the internal gear ring 374, which can be precisely controlled by adjusting the gear ring module.

[0083] Specifically, when the main shaft 31 rotates at high speed, the external gear ring 373 drives the spacer gear 372 to rotate. After the spacer gear 372 meshes with the internal gear ring 374, it drives the rotating sleeve 36 to rotate at a speed lower than that of the main shaft 31. By selecting the difference in the number of teeth between the external gear ring 373 and the internal gear ring 374, for example, the external gear ring 373 has fewer teeth than the internal gear ring 374, when the spacer gear 372 acts as an idler gear to transmit power, the rotating sleeve 36 will obtain a decelerated motion relative to the main shaft 31. This planetary gear transmission structure achieves multi-stage deceleration within a limited space, allowing the crushing mechanism 32 and the agglomeration mechanism 33 mounted on the rotating sleeve 36 to operate at speeds adapted to their functions.

[0084] Reference Figures 1-6 This application further proposes that the flow guide shroud 35 is composed of multiple coaxially spliced ​​variable diameter sleeves 351. Each variable diameter sleeve 351 has a wide diameter portion 351a and a narrow diameter portion 351b. The narrow diameter portion 351b of the lower variable diameter sleeve 351 is inserted into the wide diameter portion 351a of the adjacent upper variable diameter sleeve 351 and fixed by welding with an armature. An annular overflow gap 352 is formed between the outer wall of the narrow diameter portion 351b of the lower variable diameter sleeve 351 and the inner wall of the wide diameter portion 351a of the upper variable diameter sleeve 351. The overflow gap 352 refers to the annular channel formed by the nesting of adjacent variable diameter sleeves 351. The sludge particles after being treated by the sludge particle size control system are thrown towards the inner wall of the variable diameter sleeve 351 under the action of centrifugal force and discharged to the rising flow area outside the flow guide shroud 35 through the overflow gap 352.

[0085] Specifically, the returned sludge is crushed into optimized particle size by the crushing mechanism 32 and mixed with the wastewater in the guide hood 35. Only optimized particle size sludge and discrete small particle size sludge exist in the guide hood 35. With the action of the aggregation mechanism 33, the discrete sludge is captured. Under the disturbance of the aggregation mechanism 33, radial flow is generated in the guide hood 35. Multiple variable diameter sleeves 351 are nested and spliced ​​to form a continuous flow channel of the guide hood 35. The optimized sludge particles with larger particle size are partially thrown towards the inner wall of the variable diameter sleeve 351 under the action of centrifugal force. Under the action of gravity, they settle and are discharged through the overflow gap, directly entering the rising flow zone outside the guide hood 35 to participate in the reaction.

[0086] This application further proposes that the crushing mechanism 32 includes a fixed blade group 321 radially installed on the inner wall of the top variable diameter sleeve 351 and a moving blade group 322 radially installed on the outer wall of the rotating sleeve 36, with the fixed blade group 321 and the moving blade group 322 arranged alternately in the vertical direction.

[0087] Among them, the fixed blade group 321 refers to the static blade assembly fixed on the inner wall of the variable diameter sleeve 351 at the top of the guide shroud 35. Specifically, multiple blades can be evenly distributed into a group along the circumference of the sleeve by welding or bolting, and then multiple groups can be set along the axial direction. The fixed blade group 321 and the moving blade group 322 are staggered in axial height to form multiple crushing areas.

[0088] Specifically, when the rotating sleeve 36 is driven to rotate, the moving blade group 322 moves in a circular motion with the rotating sleeve 36, while the fixed blade group 321 remains stationary. As the sludge mixture flows downwards within the guide shroud 35, large-diameter clumps of sludge first contact the shear zone formed by the fixed blade group 321 and the moving blade group 322 at the top layer. During this process, the relative motion between the moving blade group 322 and the fixed blade group 321 generates shear force, initially cutting the sludge clumps. The initially broken sludge continues to move downwards axially, entering the next layer of alternating moving and fixed blade groups 321, where it undergoes secondary shearing. The vertically alternating arrangement increases the effective shear area within a limited space, while the axial spacing between adjacent blade groups provides a buffer zone for the fluid, reducing sludge leakage and avoiding the problem of anaerobic bacteria death inside the particles due to insufficient hydraulic shear in traditional processes. The broken medium-diameter particles have better mass transfer efficiency and settling performance, enabling them to stably participate in subsequent anaerobic ammonia oxidation reactions, thereby improving the system's denitrification efficiency and operational stability.

[0089] Reference Figure 1 and Figures 3-8 This application further proposes that the polymerization mechanism 33 includes multiple elastic frame plates 331, the inner ends of which are fixedly installed on the rotating sleeve 36. In the natural state, the outer ends of the elastic frame plates 331 extend beyond the variable diameter sleeve 351. After installation, they are in a bent state and continuously abut against the inner wall of the variable diameter sleeve 351. The elastic frame plates 331 refer to plate-shaped structures with elastic deformation capabilities. Specifically, they can be made of spring steel or polymer composite materials. The pre-bending installation forms a continuous contact pressure to ensure dynamic contact with the inner wall of the sleeve during rotation.

[0090] The grid-type collection net 332 is installed on the elastic frame plate 331. The grid-type collection net 332 refers to a filter medium with a grid structure, which can be a stainless steel wire woven mesh or a nylon mesh, used to intercept small-diameter sludge flocs that move with the fluid.

[0091] The inner wall of the variable diameter sleeve 351 is provided with wedge-shaped protrusions 353, and rollers 333 are installed at the outer end of the elastic frame plate 331 to roll in contact with the inner wall of the sleeve. The wedge-shaped protrusions 353 refer to the triangular protrusions distributed circumferentially along the inner wall of the variable diameter sleeve 351, which are used to periodically squeeze the end of the elastic frame plate 331 during rotation. The rollers 333 refer to the rotatable cylindrical contact parts, which reduce the contact resistance between the elastic frame plate 331 and the inner wall of the variable diameter sleeve 351 through rolling friction.

[0092] Specifically, when the elastic frame plate 331 rotates under the drive of the rotating sleeve 36, the rotating sleeve 36 drives the elastic frame plate 331 and its rollers 333 to rotate synchronously. During the rotation, the grid-type collection net 332 traps the discrete sludge in the wastewater on its surface and agglomerates it. When the rollers 333 contact and climb the inclined surface of the wedge-shaped protrusion 354, they force the elastic frame plate 331 to undergo greater elastic deformation and contract towards the center. When the rollers 333 pass the highest point of the wedge-shaped protrusion 354, the elastic potential energy accumulated in the elastic frame plate 331 is quickly released, driving it to reset outward and generate a shaking perpendicular to the direction of rotation. This shaking is transmitted to the grid-type collection net 332, causing the sludge flocs trapped on it to be shaken off.

[0093] The wedge-shaped protrusions 354 are numerous and evenly distributed along the circumference of the inner wall of the variable diameter sleeve 351. This causes the elastic frame plate 331 to vibrate multiple times per revolution of the rotating sleeve 36. This periodic deformation causes the grid-type collection net 332 to vibrate at high frequency, which in turn causes the captured fine sludge flocs to collide with each other. The flocs that are not intercepted repeatedly pass through the collection net under the drive of the circulating flow field, gradually agglomerating into medium-sized particles, thereby promoting the aggregation of small-sized sludge.

[0094] The rolling contact of the rollers 333 avoids wear caused by rigid scraping, while the vibration frequency excited by the bumps can prevent sludge from being pushed and blocked on the surface of the grid-type collection screen 332, and can also promote the sludge aggregation speed.

[0095] This application further proposes that the flow guiding mechanism 34 is an axial flow impeller, which is mounted on the main shaft 31. When rotating, it generates an axial thrust from top to bottom in the flow guiding shroud 35, forming an internal circulation flow path opposite to the direction of the external upward flow.

[0096] When the axial impeller rotates, it creates a downward axial water flow inside the guide shroud 35. This water flow forms a counter-current circulation with the natural upward flow generated by the water distribution at the bottom of the reaction tank. The forced flow in the downward flow zone causes the sludge mixture to move downward within the guide shroud 35, and then it is discharged from the bottom of the guide shroud 35 to the external upward flow zone, forming a continuous internal and external circulation path. This balances the contradiction between the sludge settling velocity and the water flow upward velocity, allowing sludge of different particle sizes to be gradually homogenized during the circulation process. It can prevent discrete sludge from being carried out of the system due to excessive upward flow velocity, and avoid large sludge particles from having their core mass transfer hindered due to excessive settling velocity, thereby maintaining the activity of anaerobic ammonia oxidizing bacteria and improving denitrification efficiency.

[0097] Reference Figures 1-2 and Figure 9This application further proposes a three-phase separation component 4 including multiple concentrically arranged baffle rings 41. The cross-section of the baffle rings 41 is L-shaped with unequal widths. A triangular intercepting gas chamber 412 is formed below each baffle ring 41. The long plate surface of the baffle ring 41 is close to the center of the reaction tank body 1 and extends to the lower end of the short plate surface of the adjacent baffle ring 41, forming a sludge return gap 411 between two adjacent baffle rings 41. The nitrogen gas generated in the sludge reaction zone rises rapidly in the sludge water and finally settles in the intercepting gas chamber 412. The long plate surface and the short plate surface of the baffle ring 41 are misaligned, blocking the position of the sludge return gap 411 in the longitudinal projection, thus ensuring that all nitrogen gas can be intercepted in the intercepting gas chamber 412 when it rises. The multiple baffle rings 41 are connected and supported by multiple gas guide pipes 42. 42 is connected to the intercepting gas chamber 412. The nitrogen gas in the intercepting gas chamber 412 is discharged to the outside through the gas guide pipe 42. There are multiple gas guide pipes 42. The multiple gas guide pipes 42 converge at the top of the reaction tank body 1 and are connected to the main exhaust pipe. The sludge return gap 411 allows the sludge water to pass through and reach the top of the baffle ring 41. After the sludge water passes through the baffle ring 41, it is no longer affected by the sludge water circulation in the sludge reaction zone. The activated sludge in the sludge water gradually settles and falls on the upper surface of the baffle ring 41. It flows back down along the baffle ring 41. Finally, the sludge returns to the sludge reaction zone through the sludge return gap 411. Since the long plate surface of the baffle ring 41 is close to the center of the reaction tank body 1, the returned sludge tends to move towards the position of the guide hood 35, which is conducive to continuing to circulate through the guide hood 35 and ensuring the effective content of activated sludge in the sludge reaction zone.

[0098] At the center of the baffle ring 41 is an inverted cone-shaped sedimentation hood 43, which is coaxial with the flow guide hood 35. Above the baffle ring 41 is an overflow weir 44 fixed to the inner wall of the reaction tank body 1, forming an outlet area between the overflow weir 44 and the inner wall of the reaction tank body 1. The top of the overflow weir 44 extends beyond the sedimentation hood 43 and is equipped with a water-blocking ring 45. The water-blocking ring 45 extends into the sedimentation hood 43 and has a water flow channel between it and the sedimentation hood 43. Multiple coaxially installed annular inclined plates 46 are installed in the water flow channel. The discrete sludge in the wastewater cannot be quickly settled and returned, and some of the discrete sludge is suspended in the wastewater. The wastewater enters the sedimentation hood 43, where the remaining small sludge particles are collected and flocculated by the annular inclined plate 46 and then flow back into the sludge reaction zone. After the wastewater rises, the upper layer of clear water overflows the overflow weir 44 and reaches the effluent zone. The reaction tank body 1 is equipped with a drain pipe connected to the effluent zone, and the water in the effluent zone is discharged outward through the drain pipe. By setting a water-blocking ring 45, the direction of the water flow can be restricted, so that the water flow must first pass through the annular inclined plate 46 to settle the sludge before it can overflow into the overflow weir 44. This allows the sludge in the wastewater to settle in the annular inclined plate 46 first, ensuring that the sludge and wastewater are completely separated.

[0099] Specifically, when the mixed liquor rises to the three-phase separation component 4, the bubbles are trapped in the interception chamber 412 by the long plate surface of the L-shaped blocking ring 41, and the gas is discharged through the gas guide pipe 42 to avoid interfering with the settling. Solid sludge settles downward along the sludge return gap 411 between adjacent blocking rings 41, and after being collected by the inverted conical sedimentation hood 43, it flows back into the descending flow area at the top of the guide hood 35. The liquid carrying the unsettled discrete sludge enters the water flow channel between the water-blocking ring 45 and the sedimentation hood 43. When it flows through the multi-layer annular inclined plate 46, it settles on the surface of the annular inclined plate 46 and slides back to the reaction zone. The treated clear liquid overflows through the overflow weir 44, ensuring that the settled sludge is accurately returned to the circulation path and maintaining the stability of the sludge bed.

[0100] This application further proposes a treatment method for zero-discharge treatment equipment for coal-to-ethylene glycol wastewater, including the following steps:

[0101] S1: The pretreated coal-to-ethylene glycol wastewater is introduced into the bottom of the reaction tank 1 through the wastewater distribution component 2. The water distribution process agitates the bottom sludge to form an upward flow, so that the wastewater and activated sludge are fully mixed and enter the sludge reaction zone.

[0102] S2: Start motor 5 drives main shaft 31 to rotate, thereby driving the sludge particle size control system to operate;

[0103] The flow guiding mechanism 34 forms an axial flow field from top to bottom inside the flow guide shroud 35, which forces the mud-water mixture to flow downward in the descending flow zone.

[0104] After the mixture in the descending flow zone is discharged from the bottom of the guide shroud 35, it enters the rising flow zone outside the shroud and moves upward, thus forming a continuous internal and external circulation flow between the inside and outside of the guide shroud 35.

[0105] The crushing mechanism 32 mechanically shears and crushes large-diameter sludge clumps in the circulating flow, breaking them down into medium-diameter particles.

[0106] The aggregation mechanism 33 captures and retains discrete small-diameter sludge flocs in the circulating flow, and promotes their collision and aggregation to form medium-diameter particles.

[0107] S3: After being regulated by step S2, the activated sludge with a more uniform particle size undergoes anaerobic ammonia oxidation reaction with ammonia nitrogen and nitrite nitrogen in the wastewater in the upflow zone.

[0108] S4: The gas-liquid-solid mixture after the reaction rises to the three-phase separation component 4;

[0109] The gas is trapped in the interception chamber 412 and collected and discharged through the gas guide tube 42;

[0110] Some solid sludge settles along the sludge return gap 411 between the blocking rings 41, and after being collected by the sedimentation hood 43, it is guided back to the inlet of the descending flow zone at the top of the guide hood 35 to achieve sludge return.

[0111] The separated supernatant and some fine suspended matter that failed to settle enter the clean water outlet channel formed by the water baffle ring 45 and the inner wall of the sedimentation hood 43, flow through the surface of the annular inclined plate 46, the fine suspended matter settles on the surface of the annular inclined plate 46 and slides back to the reaction zone, and the treated supernatant overflows through the overflow weir 44.

[0112] S5: The treated water discharged from the overflow weir 44 enters the subsequent deep treatment and zero-discharge section until it meets the standards.

Claims

1. A zero-discharge treatment device for coal-to-ethylene glycol wastewater, comprising a reaction tank (1), characterized in that, The reaction vessel body (1) is provided with the following components from bottom to top: Wastewater distribution assembly (2) is installed at the bottom of the reaction tank body (1) to introduce wastewater and agitate the bottom sludge to form an upward flow; The circulating reaction assembly (3) is located in the sludge reaction zone in the middle of the tank. The circulating reaction assembly (3) includes a vertically arranged guide hood (35) and a main shaft (31) coaxially arranged with the guide hood (35). The main shaft (31) is driven by a motor (5) installed at the bottom of the tank body (1). The guide hood (35) is equipped with a sludge particle size control system controlled by the main shaft (31). The sludge particle size control system is configured to be able to perform in-situ control of the returned sludge so that the particle size distribution of the sludge particles tends to be uniform. The three-phase separation component (4) is located at the top of the reaction vessel body (1) and is used to achieve gas, liquid and solid three-phase separation; The flow guide hood (35) divides the sludge reaction zone into an internal descending flow zone and an external ascending flow zone. The return sludge separated by the three-phase separation component (4) is guided to the top of the descending flow zone and, after being processed by the sludge particle size control system, is discharged from the bottom of the flow guide hood (35) to the ascending flow zone.

2. The zero-discharge treatment equipment for coal-to-ethylene glycol wastewater according to claim 1, characterized in that, The sludge particle size control system includes: Crushing mechanism (32), which is used to crush large-diameter agglomerated sludge particles; Aggregation mechanism (33), which is used to promote the aggregation of discrete small-particle-size sludge flocs; A flow guiding mechanism (34) is used to form an axial circulating flow field within the circulating reaction assembly (3); The crushing mechanism (32), the agglomeration mechanism (33) and the flow guiding mechanism (34) are arranged from top to bottom inside the flow guiding shroud (35), and the main shaft (31) passes through the flow guiding shroud (35) and drives the various mechanisms to operate synchronously.

3. The zero-discharge treatment equipment for coal-to-ethylene glycol wastewater according to claim 2, characterized in that, A rotating sleeve (36) is fitted on the main shaft (31), and a speed reduction transmission structure (37) is provided between the main shaft (31) and the rotating sleeve (36) so that the rotating sleeve (36) can rotate at different speeds when the main shaft (31) rotates. The crushing mechanism (32) and the agglomeration mechanism (33) are mounted on the rotating sleeve (36) and driven by it, and the flow guiding mechanism (34) is mounted on the main shaft (31) and driven by it directly.

4. The zero-discharge treatment equipment for coal-to-ethylene glycol wastewater according to claim 3, characterized in that, The speed reduction transmission structure (37) includes a support frame (371) fixedly installed at the upper and lower ends of the rotating sleeve (36), and at least three spacer gears (372) are rotatably installed on the support frame (371). An external gear ring (373) is fixedly installed on the outer wall of the main shaft (31), which meshes with the spacer gear (372); An internal gear ring (374) is fixedly provided on the inner wall of the rotating sleeve (36), which meshes with the spacer gear (372); The reduction ratio of the rotating sleeve (36) relative to the main shaft (31) is controlled by the tooth ratio of the external gear ring (373), the spacer gear (372) and the internal gear ring (374).

5. The zero-discharge treatment equipment for coal-to-ethylene glycol wastewater according to claim 3, characterized in that, The flow guide (35) is composed of multiple coaxially spliced ​​variable diameter sleeves (351); Each of the variable diameter sleeves (351) has a wide diameter portion (351a) and a narrow diameter portion (351b). The narrow diameter portion (351b) of the lower variable diameter sleeve (351) is inserted into the wide diameter portion (351a) of the adjacent upper variable diameter sleeve (351) and fixed by welding with an armature. An annular overflow gap (352) is formed between the outer wall of the narrow diameter portion (351b) of the lower variable diameter sleeve (351) and the inner wall of the wide diameter portion (351a) of the upper variable diameter sleeve (351). After the sludge particle size is optimized by the sludge particle size control system, the sludge particles are thrown towards the inner wall of the variable diameter sleeve (351) under the action of centrifugal force, and discharged into the rising flow area outside the guide shroud (35) through the overflow gap (352) under the action of gravity.

6. The zero-discharge treatment equipment for coal-to-ethylene glycol wastewater according to claim 5, characterized in that, The crushing mechanism (32) includes a fixed blade group (321) radially installed on the inner wall of the top variable diameter sleeve (351) and a moving blade group (322) radially installed on the outer wall of the rotating sleeve (36). The fixed blade group (321) and the moving blade group (322) are arranged alternately in the vertical direction.

7. The zero-discharge treatment equipment for coal-to-ethylene glycol wastewater according to claim 5, characterized in that, The aggregation mechanism (33) includes: Multiple elastic frame plates (331) are fixedly installed on the rotating sleeve (36) at their inner ends; A grid-type collection net (332) is installed on the elastic frame plate (331) to trap fine sludge flocs; In its natural state, the outer end of the elastic frame plate (331) extends beyond the variable diameter sleeve (351), so that the elastic frame plate (331) is bent after being installed in the variable diameter sleeve (351), and its outer end continuously abuts against the inner wall of the variable diameter sleeve (351). At least one wedge-shaped protrusion (353) is provided on the inner wall of the variable diameter sleeve (351). The outer end of the elastic frame plate (331) is equipped with a roller (333), which makes rolling contact with the inner wall of the variable diameter sleeve (351).

8. The zero-discharge treatment equipment for coal-to-ethylene glycol wastewater according to claim 1, characterized in that, The flow guiding mechanism (34) is an axial flow impeller, which is installed on the main shaft (31). When it rotates, it generates an axial thrust from top to bottom in the flow guiding shroud (35), forming an internal circulation flow path opposite to the direction of the external upward flow.

9. The zero-discharge treatment equipment for coal-to-ethylene glycol wastewater according to claim 1, characterized in that, The three-phase separation component (4) includes multiple concentrically arranged baffle rings (41). The cross-section of the baffle rings (41) is L-shaped with unequal widths. A triangular intercepting gas chamber (412) is formed below each baffle ring (41). The long plate of the baffle ring (41) is close to the center of the reaction tank body (1) and extends to the lower end of the short plate of the adjacent baffle ring (41). A sludge return gap (411) is formed between two adjacent baffle rings (41). The multiple baffle rings (41) are connected and supported by multiple gas guide pipes (42), and the gas guide pipes (42) are connected to the intercepting gas chamber (412). The center of the blocking ring (41) has an inverted cone-shaped sedimentation hood (43). The sedimentation hood (43) is coaxial with the flow guide hood (35). An overflow weir (44) fixed to the inner wall of the reaction tank body (1) is provided above the blocking ring (41). A water outlet area is formed between the overflow weir (44) and the inner wall of the reaction tank body (1). The top of the overflow weir (44) extends beyond the sedimentation hood (43) and is provided with a water-blocking ring (45). The water-blocking ring (45) extends into the sedimentation hood (43) and has a water flow channel between it and the sedimentation hood (43). A multi-layer coaxially installed annular inclined plate (46) is provided in the water flow channel.

10. A treatment method for zero-discharge treatment equipment for coal-to-ethylene glycol wastewater, using the treatment equipment as described in any one of claims 1-9, characterized in that, Includes the following steps: S1: The pretreated coal-to-ethylene glycol wastewater is introduced into the bottom of the reaction tank (1) through the wastewater distribution component (2). The water distribution process agitates the bottom sludge to form an upward flow, so that the wastewater and activated sludge are fully mixed and enter the sludge reaction zone. S2: Start the motor (5) to drive the main shaft (31) to rotate, thereby driving the sludge particle size control system to run; An axial flow field from top to bottom is formed inside the flow guide shroud (35) by the flow guide mechanism (34), which forces the mud-water mixture to flow downward in the descending flow zone; After the mixture in the descending flow zone is discharged from the bottom of the guide shroud (35), it enters the rising flow zone outside it and moves upward, thereby forming a continuous internal and external circulation flow between the inside and outside of the guide shroud (35). The large-diameter sludge clumps are mechanically sheared and crushed in the circulating flow by the crushing mechanism (32), so that they are decomposed into medium-diameter particles. The aggregation mechanism (33) captures and retains discrete small-diameter sludge flocs in the circulating flow and promotes their collision and aggregation to form medium-diameter particles. S3: After being regulated by step S2, the activated sludge with a more uniform particle size undergoes anaerobic ammonia oxidation reaction with ammonia nitrogen and nitrite nitrogen in the wastewater in the upflow zone. S4: The gas-liquid-solid mixture after the reaction rises to the three-phase separation component (4). The gas is trapped in the interception chamber (412) and collected and discharged through the gas guide tube (42); Some solid sludge settles along the sludge return gap (411) between the blocking rings (41), and after being collected by the sedimentation hood (43), it is guided back to the inlet of the descending flow zone at the top of the guide hood (35) to achieve sludge return; The separated clear liquid and some fine suspended matter that failed to settle enter the clean water outlet channel formed by the water baffle ring (45) and the inner wall of the sedimentation hood (43), flow through the surface of the annular inclined plate (46), the fine suspended matter settles on the surface of the annular inclined plate (46) and slides back to the reaction zone, and the treated supernatant overflows through the overflow weir (44). S5: The treated water discharged from the overflow weir (44) enters the subsequent deep treatment and zero-discharge section until it meets the standards.

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