A multi-stage water distribution crystallization prilling softening device

Abstract

The utility model provides a kind of crystallization granulation softening device of multistage water distribution, including cylinder, and water distribution area, reaction granulation area, sedimentation area, separation area and clear water area are sequentially arranged in cylinder along water flow direction, water distribution area is provided with multistage water distribution mechanism that is sequentially communicated, multistage water distribution mechanism includes the first-stage water distribution mechanism in front stage and the second-stage water distribution mechanism in rear stage;First-stage water distribution mechanism includes water inlet main pipe and several water distribution branch pipes communicated with water inlet main pipe, water distribution branch pipe is provided with water distribution hole on pipe wall;Second-stage water distribution mechanism includes a horizontally arranged porous baffle and a plurality of microporous water distribution caps fixedly installed on the porous baffle.The utility model can replace conventional reactor, realizes fluidized bed layer stability, medicament mixing is uniform, mass transfer efficiency is high, water quality is stable, while aiming at the case that suspended solid of raw water is high, can be set to remove by dosing, greatly improve the operability of device.

Description

Technical Field

[0001] This utility model relates to the technical field of water treatment devices, specifically, it demonstrates a multi-stage water distribution crystallization granulation softening device. Background Technology

[0002] Industrial production generates large quantities of high-hardness wastewater, such as wastewater from the paper industry and concentrated water from reverse osmosis systems. Water hardness is a key control indicator in industrial water use, a major obstacle to the safety of industrial water system equipment, and a key challenge in achieving zero wastewater discharge in industrial production. Many effective softening methods exist for treating hardness wastewater, including coagulation, flocculation, and sedimentation softening, adsorption and ion exchange, and crystallization granulation softening technology. Among these, crystallization granulation softening technology, with its high efficiency, low cost, and small footprint, is the future mainstream core technology for hard water softening.

[0003] Crystallization granulation softening technology involves adding micro-particle solid fillers as seed crystals to the reaction system, along with reaction agents. By adjusting the supersaturation of the high-hardness water and the upward flow rate of the carrier, pretreated inorganic ions (such as calcium and magnesium ions) form stable crystals (calcium carbonate crystals) on the carrier surface. Once the crystal particle size reaches a certain level, they are discharged from the tank, thereby effectively reducing the hardness of the water.

[0004] Crystallization granulation softening treatment devices are currently used both domestically and internationally. However, due to structural design issues, problems such as unstable bed, uneven reagent mixing, low mass transfer efficiency, high residual hardness in effluent, and easy loss of crystallized particles may occur. Utility Model Content

[0005] The purpose of this invention is to provide a multi-stage water distribution crystallization granulation softening device with a simple structure and reasonable design.

[0006] The technical solution is as follows: A multi-stage water distribution crystallization granulation softening device includes a cylindrical body, and water inlet distribution zone, reaction granulation zone, sedimentation zone, separation zone and clear water zone sequentially arranged along the water flow direction within the cylindrical body, wherein: The water inlet and distribution area is provided with a multi-stage water distribution mechanism connected in sequence. The multi-stage water distribution mechanism includes a first-stage water distribution mechanism at the front stage and a second-stage water distribution mechanism at the rear stage. The first-stage water distribution mechanism includes a main water inlet pipe and several water distribution branch pipes connected to the main water inlet pipe. Water distribution holes are opened on the pipe walls of the water distribution branch pipes. The second-stage water distribution mechanism includes a horizontally arranged porous baffle and several microporous water distribution caps fixedly installed on the porous baffle.

[0007] In addition, the above embodiments of this utility model may also have the following additional technical features: According to one embodiment of this utility model, the bottom of the reaction granulation zone is filled with crystal nucleation packing material. An inlet and an outlet are provided on the cylinder corresponding to the lower part of the reaction granulation zone, and an observation port is provided on the upper part of the cylinder. The inlet is used for initial filling and replenishment of seed crystals; the outlet is used to periodically discharge excessively grown crystal particles to maintain the optimal particle size distribution of the bed; the observation port allows operators to directly observe the fluidization state and crystallization status inside the device, facilitating monitoring and adjustment of operating parameters and reducing the failure rate.

[0008] In one embodiment, the system further includes a dosing system comprising a main dosing pipe positioned at the top of the inlet water distribution zone and multiple downwardly extending branch dosing pipes, each branch pipe having a dosing nozzle at its end. The chemical is added to the top of the inlet water distribution zone, ensuring it comes into full contact with the water flow before entering the reaction zone, promoting rapid and uniform mixing of the chemical and improving crystallization efficiency.

[0009] In other embodiments, the dosing system further includes an external dosing pipe connected to the main inlet pipe. Coagulants can be added through this external dosing pipe to induce a coagulation reaction and initially remove suspended solids and colloids.

[0010] According to one embodiment of this utility model, a reflector plate and an inclined plate assembly are provided above the reflector plate in the settling zone. This enhances the solid-liquid separation effect in the settling zone.

[0011] According to one embodiment of this utility model, a microporous filter is provided in the separation zone. This serves as a deep filter, further reducing the turbidity of the effluent and ensuring that the final effluent water quality is clear and stable.

[0012] According to one embodiment of this utility model, a pH meter and an online turbidity detector are installed on the side wall or top of the clear water zone to monitor the pH and turbidity of the effluent in real time.

[0013] In one embodiment, the pH meter and the online turbidity detector are connected to a PLC controller via signal lines. The PLC controller can automatically adjust the dosage of the dosing pump based on real-time water quality data (such as pH value), achieving precise and automated dosing.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model presents a multi-stage water distribution crystallization granulation softening treatment device that replaces conventional reactors. It achieves stable fluidized bed, uniform reagent mixing, high mass transfer efficiency, and stable effluent quality. Furthermore, it addresses the issue of high suspended solids in the raw water by implementing chemical dosing to remove them, greatly improving the operability of the device.

[0015] The crystallization granulation softening device comprises an inlet water distribution zone, a reaction granulation zone, a sedimentation zone, a separation zone, and a clear water zone. A partition separates the water distribution zone from the granulation zone. Water is distributed into the water distribution zone via a water distribution pipeline, while chemicals are delivered into the chemical distribution branch pipes via a chemical distribution pipeline. Multiple sets of chemical distributors are installed on the chemical distribution branch pipes. The chemicals output from the chemical distributors, the water in the water distribution zone, and the seeds added at the seed crystal addition port are sprayed vertically upwards from the output port, then rise along the inner wall of the device to the sedimentation zone, collide, and sink to the bottom, creating a circulating flow within the device. This enhances the fluidized bed effect of the crystallization granulation process, improves the uniformity of chemical mixing, increases the growth rate and efficiency of crystallized particles, significantly reduces the hardness of the effluent, and lowers the failure rate of the crystallization granulation softening device. Attached Figure Description

[0016] Figure 1 This is a simplified schematic diagram of a multi-stage water distribution crystallization granulation softening device according to Embodiment 1 of this utility model; Figure 2 This is a simplified schematic diagram of the primary water distribution mechanism in Embodiment 1 of this utility model; Figure 3 This is a simplified schematic diagram of the two-stage water distribution mechanism in Embodiment 1 of this utility model; Figure 4 This is a system block diagram of the dosing system in Embodiment 1 of this utility model; The relevant markings in the attached diagram are as follows: 100-cylinder, 1-water inlet and distribution zone, 2-reaction granulation zone, 3-sedimentation zone, 4-separation zone, 5-clear water zone, 6-primary water distribution mechanism, 7-secondary water distribution mechanism, 8-dosing system; 21-feed inlet, 22-discharge outlet, 23-observation port, 31-reflector plate, 32-inclined plate group, 41-microporous filter, 51-pH meter, 52-online turbidity detector, 61-main water inlet pipe, 62-branch water distribution pipe, 63-water distribution hole, 71-porous baffle plate, 72-microporous water distribution cap, 81-main dosing pipe, 82-branch dosing pipe, 83-dosing nozzle, 84-external dosing pipe. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Example 1 This embodiment provides a multi-stage water distribution crystallization granulation softening device, the main body of which is a vertically oriented cylindrical body. This body 100 can be made of corrosion-resistant materials such as carbon steel lined with rubber, stainless steel (e.g., 304 or 316L), or fiberglass. Its specific dimensions can be adjusted according to the water treatment capacity (e.g., 10 tons, 50 tons, 100 tons per hour, etc.). From bottom to top, the interior of the body 100 is sequentially divided by internal components into an inlet water distribution zone 1, a reaction granulation zone 2, a sedimentation zone 3, a separation zone 4, and a clear water zone 5. Each section has a clearly defined function and is closely connected, together forming a highly efficient and continuous crystallization granulation softening system.

[0019] The water inlet distribution zone 1 is located at the bottom of the device. Its core function is to receive pressurized raw water (such as high-hardness wastewater) from the water inlet pump (not shown in the figure) and distribute the water flow evenly and stably to the entire cross-section of the reactor through a unique multi-stage water distribution mechanism, laying the foundation for the stability of subsequent reactions.

[0020] The multi-stage water distribution mechanism consists of a primary water distribution mechanism 6 and a secondary water distribution mechanism 7 connected in series.

[0021] See Figure 2 As shown, the primary water distribution mechanism 6 is essentially a branched perforated pipe system. It includes a horizontally positioned main inlet pipe 61 (the diameter of which can be determined according to the flow rate, for example, DN100). This main inlet pipe 61 extends from the side wall of the cylinder 100 into the water distribution area 1. Several water distribution branch pipes 62 (e.g., 4 or 6, evenly and symmetrically distributed) are vertically connected to the main inlet pipe 61. These branch pipes 62 are also tubular structures with a diameter smaller than the main inlet pipe 61 (e.g., DN50). Preferably, the branch pipes 62 are evenly distributed on the bottom plane of the water distribution area 1 to ensure coverage of the entire area. On the upper part and side wall of all water distribution branch pipes 62, a large number of water distribution holes 63 of the same diameter (e.g., hole diameter 5-10mm) are drilled at specific intervals (e.g., 100mm) and specific angles (e.g., 45 degrees upwards). When pressurized raw water first enters the main water inlet pipe 61, it is then distributed to each water distribution branch pipe 62. Finally, through these water distribution holes 63, the first energy dissipation and preliminary distribution are carried out, which can complete the dispersal of a concentrated water flow into multiple small water flows, and initially equalize the water pressure and flow rate.

[0022] See Figure 3As shown, the secondary water distribution mechanism 7 is located above the primary water distribution mechanism 6. A porous baffle 71 is horizontally mounted on it. This porous baffle 71 is sealed to the inner wall of the cylinder 100, physically separating the water inlet distribution zone 1 from the upper reaction granulation zone 2, but allowing water flow through. The porous baffle 71 itself has uniformly distributed water passage holes, and a microporous water distribution cap 72 is fixedly installed on each water passage hole. The microporous water distribution cap is a mature water distribution element, usually made of ABS or stainless steel, and has dense, micron-level gaps inside (e.g., gap width 0.1-0.3 mm). The water flow after the primary water distribution must pass through the gaps of these microporous water distribution caps from below to enter the reaction granulation zone 2. The function of the secondary water distribution is to perform final fine water distribution. The micron-level gaps can generate huge resistance, dissipating the residual kinetic energy of the water flow and ensuring that the water flow passes vertically upward through the entire cross-section of the reaction granulation zone 2 at an extremely uniform flow rate. This effectively solves the technical problem of "bed instability".

[0023] The reaction granulation zone 2 is the core area where the crystallization reaction occurs. It is located above the secondary water distribution mechanism 7 and is filled with crystal nucleus packing. The height of this zone is one of the key design parameters, and it usually accounts for 1 / 3 to 1 / 2 of the total height of the cylinder.

[0024] The nucleus filler in the reaction granulation zone 2 is usually high-quality quartz sand or inert material particles with a particle size between 0.2 and 0.5 mm. When the device is started for the first time, a certain height (e.g., 1.5 meters) of nucleus filler is put in through the feed port 21 (usually equipped with a flange cover) located on the side wall of the cylinder and at the bottom of the reaction granulation zone 2. These filler particles serve as crystal seeds and provide a huge specific surface area.

[0025] The apparatus also includes a dosing system 8 for adding reactants thereto, see [reference]. Figure 4 As shown, the dosing system consists of two parts: The main dosing device includes a main dosing pipe 81 located at the top of the water inlet distribution area 1, and several vertically downward dosing branch pipes 82 extending from the main dosing pipe 81. Each branch pipe 82 is equipped with a dosing nozzle 83 (such as a spray nozzle) at its end. The spray direction of the dosing nozzle 83 is vertically downward, directly facing the secondary water distribution mechanism 7 below. The reaction agents (sodium carbonate Na2CO3 solution and sodium hydroxide NaOH solution in this embodiment) are delivered to the main dosing pipe through an external metering pump, and then sprayed evenly in a mist or droplet form on the upper surface of the secondary water distribution mechanism 7 through the branch pipes and nozzles. When the water flows up through the water distribution cap, it immediately mixes with the evenly distributed agents. This design ensures that the agents are initially mixed before entering the crystal nucleation bed, solving the problem of "uneven agent mixing".

[0026] External dosing port: It is directly connected to the main inlet pipe 61 of the device through the external dosing pipe 84. The external dosing pipe is mainly used to add coagulants (such as PAC, polyaluminum chloride) when the concentration of suspended solids (SS) in the inlet water is high, so that the coagulation reaction starts in the pipe before entering the device, removes some suspended solids and colloids, and broadens the adaptability of the device to water quality.

[0027] An observation port 23, typically one or more transparent sight glasses, is provided on the side wall of the reaction granulation zone 2 for direct observation of the fluidization state, particle size, and scaling of the internal seed crystals. At the bottom of the reaction granulation zone 2, a discharge port 22 is provided for periodically discharging particles that are too large due to crystal growth, in order to maintain the stability and activity of the fluidized bed.

[0028] Settling zone 3 is located above reaction granulation zone 2 and is a gradually expanding space. In this zone, the fluidized crystal nuclei carried by the water flow rising from the fluidized bed will collide, aggregate, and settle.

[0029] To enhance the settling effect, this device incorporates specialized internal components in settling zone 3. A reflector plate 31: At the lower part of settling zone 3, one or more reflector plates (or baffles) are installed. These reflector plates are typically horizontal or slightly angled plates. When rising water and particles collide with the reflector plates, the flow direction changes, and the flow velocity decreases, which facilitates collisions and kinetic energy dissipation between particles, thus promoting particle settling. An inclined plate assembly 32: Above the reflector plates, an inclined plate assembly (also called inclined tube packing) is installed. This assembly consists of numerous parallel plastic plates with a certain angle (usually 60°), forming many parallel shallow settling channels. This significantly increases the effective settling area, allowing tiny particles to be separated within a very short settling distance, resulting in significantly improved settling efficiency. The separated crystal nuclei slide back along the inclined plate surface to the lower reaction granulation zone 2.

[0030] After passing through settling zone 3, most of the crystallized particles have been separated, but a very small number of tiny particles may still remain in the water. Separation zone 4 is located above settling zone 3 and is equipped with a microporous filter, such as a cylindrical filter made of stainless steel mesh, with a filtration accuracy of 50 to 100 micrometers. This final physical barrier can trap any tiny particles that "slip through the net" and most of the suspended solids, ensuring clear effluent and greatly reducing turbidity.

[0031] The clear water zone 5 is located at the top of the device and is an area where the final produced water is collected. The effluent from the separation zone 4 enters the clear water zone 5. The top of the clear water zone 5 is equipped with an effluent weir and an outlet. The clear water flows into the next treatment system by gravity or pumping. On the side wall of the clear water zone 5, online monitoring instruments such as pH meters and online turbidity detectors are installed to monitor the water quality of the final effluent in real time.

[0032] The pH meter and online turbidity analyzer are connected to a PLC (Programmable Logic Controller) via signal lines. The PLC receives water quality data in real time according to a pre-set program (e.g., target pH value of effluent 9.5–10.5, turbidity <5 NTU). If the pH value deviates from the set range, the PLC outputs a signal to automatically adjust the frequency of the NaOH dosing pump, increasing or decreasing the alkali dosage. Similarly, turbidity data can also be used to assist in controlling the dosing of coagulants. This system achieves precise automatic control, ensuring treatment effectiveness while saving on reagent consumption and reducing manual operation.

[0033] The working process of this embodiment is as follows: 1. Start-up: Add an appropriate amount of quartz sand through the feed inlet as a crystal nucleus filler.

[0034] 2. Water Inlet and Distribution: After being pressurized by the inlet pump, the high-hardness wastewater enters the inlet distribution zone 1. The water flows through the primary distribution mechanism 6 (perforated branch pipe water distribution) and the secondary distribution mechanism 7 (microporous water distribution cap) in sequence to achieve uniform distribution, and then enters the reaction granulation zone 2 vertically and at a uniform speed.

[0035] 3. Crystallization reaction: Na2CO3 and NaOH solutions are added evenly through the nozzle of the main dosing device. After mixing with the rising water flow, they come into contact with the crystal nucleus packing. Ca²⁺ and Mg²⁺ in the water react with CO3²⁻ and OH⁻, and the generated CaCO3 and Mg(OH)2 crystals precipitate on the surface of the crystal nucleus, and the crystals gradually grow.

[0036] 4. Sedimentation and separation: The water carrying the crystals enters the sedimentation zone 3. Under the action of the reflector and inclined plate group, most of the crystals settle and return to the reaction zone, while the clear water continues to rise.

[0037] 5. Fine Filtration and Water Discharge: Clean water passes through the microporous filter in separation zone 4, where residual particles are trapped. Finally, the clear softened water enters the clean water zone 5 and is discharged through the outlet.

[0038] 6. Automatic control: The pH and turbidity meters in the clear water zone 5 are monitored in real time, and the data is fed back to the PLC to automatically adjust the dosage of chemicals and ensure stable operation.

[0039] 7. Slag removal: Periodically remove excessively grown crystal particles through the bottom outlet to maintain system balance.

[0040] Example 2: This embodiment has the same main structure as Embodiment 1. The main difference lies in the method of adding the reagent, which is adapted to influent with high suspended solids (SS) content, such as paper mill wastewater or RO concentrate.

[0041] In this embodiment, the external dosing pipe 84 is fully utilized to directly add coagulants (such as PAC) and coagulant aids (such as PAM) to the high-hardness wastewater conveying pipe at the front end of the device via a dosing pump. The agents and wastewater are fully mixed and reacted in the pipe to form tiny flocs, which are then carried by the water flow into the water inlet distribution area 1 of the device.

[0042] Because the flocs formed by coagulation have a certain adsorption and trapping effect, they can remove some suspended solids and colloidal substances in the water in advance. When these flocs pass through the reaction granulation zone 2, some of them will be wrapped or adsorbed by the growing crystal particles and finally removed in the settling zone 3 and separation zone 4.

[0043] The advantage of this operating method is that it organically combines coagulation pretreatment and crystallization softening processes into one device, realizing integrated treatment of high turbidity and high hardness wastewater, simplifying the process flow, and saving land area and investment costs.

[0044] The above descriptions are merely some embodiments of this utility model. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and all such modifications and improvements fall within the protection scope of this utility model.

Claims

1. A multi-stage water distribution crystallization granulation softening device, comprising a cylindrical body (100), and a water inlet distribution zone (1), a reaction granulation zone (2), a sedimentation zone (3), a separation zone (4), and a clear water zone (5) sequentially arranged in the cylindrical body (100) along the water flow direction, characterized in that: The water inlet distribution area (1) is provided with a multi-stage water distribution mechanism connected in sequence. The multi-stage water distribution mechanism includes a first-stage water distribution mechanism (6) located at the front stage and a second-stage water distribution mechanism (7) located at the rear stage. The first-stage water distribution mechanism (6) includes a main water inlet pipe (61) and several water distribution branch pipes (62) connected to the main water inlet pipe (61). Water distribution holes (63) are opened on the pipe wall of the water distribution branch pipes (62). The second-stage water distribution mechanism (7) includes a horizontally arranged porous baffle (71) and several microporous water distribution caps (72) fixedly installed on the porous baffle (71).

2. The multi-stage water distribution crystallization granulation softening device according to claim 1, characterized in that, The bottom of the reaction granulation zone (2) is filled with crystal nucleus filler. The cylinder (100) is provided with an inlet (21) and an outlet (22) corresponding to the lower part of the reaction granulation zone (2). An observation port (23) is provided at the upper part of the cylinder (100).

3. The multi-stage water distribution crystallization granulation softening device according to claim 2, characterized in that, It also includes a dosing system (8), which includes a main dosing pipe (81) located at the top of the water inlet distribution area (1) and multiple downward-extending dosing branch pipes (82), with a dosing nozzle (83) at the end of each dosing branch pipe (82).

4. The multi-stage water distribution crystallization granulation softening device according to claim 3, characterized in that, The dosing system (8) also includes an external dosing pipe (84) connected to the main water inlet pipe (61).

5. The multi-stage water distribution crystallization granulation softening device according to claim 1, characterized in that, The settling zone (3) is provided with a reflector plate (31) and an inclined plate group (32) that is inclined above the reflector plate (31).

6. The multi-stage water distribution crystallization granulation softening device according to claim 1, characterized in that, A microporous filter (41) is provided in the separation zone (4).

7. The multi-stage water distribution crystallization granulation softening device according to claim 1, characterized in that, A pH meter (51) and an online turbidity detector (52) are installed on the side wall or top of the clear water zone (5).

8. The multi-stage water distribution crystallization granulation softening device according to claim 7, characterized in that, The pH meter (51) and the online turbidity detector (52) are connected to a PLC controller via signal lines.

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