A chemical crystallization circulating granulation fluidized bed structure and system

Abstract

The utility model discloses a chemical crystallization circulating granulation fluidized bed structure and system, comprising a cylinder, wherein a water distribution area, a drug distribution area, a granulation area and a clear water area are sequentially arranged in the cylinder from the bottom to the top, the water distribution area, the drug distribution area, the granulation area and the clear water area are respectively connected through circulating water pipes, the inlet end of the water distribution area is connected with a water inlet pipe, the outlet end of the clear water area is connected with a water outlet pipe, and the drug distribution area is connected with an external drug adding pipe; the utility model adopts a scheme of chemical crystallization granulation and solid-liquid separation combination, occupies a relatively small area, has compact equipment layout, simple operation adjustment, stable operation, and is convenient for adding crystal seeds from the outside, so that the chemical crystallization circulating granulation fluidized bed can be used to remove hardness; it is more conducive to the operation of the circulating water system and the boiler feed water system in the factory; and the scheme has low water production cost, moderate investment, and is suitable for practical use.

Description

Technical Field

[0001] The utility model relates to the technical field of water treatment, in particular to a chemical crystallization circulating granulation fluidized bed structure and system. Background Art

[0002] Some thermal power companies mainly use surface water for production water. In response to the call for water conservation and environmental protection, they gradually began to use the reclaimed water from sewage treatment plants as production water. However, the reclaimed water has high hardness and contains a large number of harmful substances such as microorganisms, organic matter, bacteria, dissolved solids, etc.; with the increasing use of reclaimed water, the harm to the thermal system of power plants is becoming more and more serious. For example, condensers, cooling tower fillers, plate heat exchangers and other equipment have different degrees of corrosion, scaling and microbial breeding. In particular, scaling has a great impact on heat exchange equipment, which will cause the vacuum of the unit to decrease, the heat exchange efficiency to decrease, and affect the safety and economic production of the power plant. Therefore, it is necessary to treat the reclaimed water. The current reclaimed water treatment methods include chemical precipitation softening method, ion exchange method, etc., but they all have some problems:

[0003] (1) Chemical precipitation softening method

[0004] Principle: Chemical precipitation softening method refers to adding a certain amount of lime or caustic soda, soda ash and other agents to the raw water according to the solubility product principle, reacting with the bicarbonate, calcium and magnesium ions to form calcium carbonate and magnesium hydroxide precipitation, and finally achieving the purpose of reducing the hardness of the raw water. Adding lime to soften the raw water in the chemical precipitation softening method is a process often used in industrial water treatment.

[0005] Advantages: low price of lime, wide source, relatively low reagent cost; Disadvantages: large floor space, complex operation and management, easy to foul, difficult to control dosage, high initial investment. An important disadvantage of lime softening is that it will convert temporary hardness into permanent hardness, and the total hardness cannot be effectively reduced.

[0006] (2) Ion exchange method

[0007] Principle: Raw water passes through a cation exchanger, and the calcium and magnesium ions in the water are exchanged with the sodium ions or hydrogen ions in the exchange resin to achieve the effect of water softening; however, this method is costly, the resin needs to be regenerated, and the regenerated wastewater is difficult to treat, resulting in secondary pollution, such as high hardness, very short operating cycle, and frequent regeneration. This method is not suitable for projects with large water volume and high hardness.

[0008] Therefore, designing a new reclaimed water treatment system is an urgent problem that technicians in related fields need to solve. Utility Model Content

[0009] In order to solve the above technical problems, the technical solution provided by the utility model is: a chemical crystallization circulating granulation fluidized bed structure, including a cylinder, in which a water distribution area, a drug distribution area, a granulation area and a clear water area are arranged in sequence from bottom to top, and the water distribution area, the drug distribution area, the granulation area and the clear water area are respectively connected by circulating water pipes, the inlet end of the water distribution area is connected to a water inlet pipe, the outlet end of the clear water area is connected to a water outlet pipe, and the drug distribution area is connected to an external drug adding pipe; the granulation area is divided into three areas from bottom to top, the bottom of the granulation area is a fluidizing area, the top is a separation area, and the middle is a static settling area; the inlet end of the fluidizing area is connected to an external seed adding pipe, and the outlet end is connected to a particle discharge pipe.

[0010] The utility model also discloses a chemical crystallization circulating granulation fluidized bed system, comprising a circulating granulation fluidized zone, a sludge concentration zone, a sludge separation zone and a water collection zone which are connected in sequence, wherein the water collection zone is connected to the sludge concentration zone via a return pipe; a plurality of groups of cylinders are arranged in the circulating granulation fluidized zone, a plurality of sludge concentration fluidized beds are arranged in the sludge concentration zone, a plurality of solid-liquid separation fluidized beds are arranged in the sludge separation zone, and an outlet of the sludge concentration fluidized bed is connected to an inlet of the solid-liquid separation fluidized bed.

[0011] The advantages of the utility model compared with the prior art are:

[0012] The utility model adopts a scheme of chemical crystallization granulation and solid-liquid separation combination, which occupies a relatively small area, has a compact equipment layout, simple operation adjustment, stable operation, and is convenient for adding crystal seeds from the outside, so that the hardness can be removed by using the chemical crystallization circulating granulation fluidized bed; it is more conducive to the operation of the circulating water system and the boiler feed water system in the factory; and the scheme has a low water production cost, moderate investment, and is suitable for practical use. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the cylinder in the utility model.

[0014] Figure 2 It is a schematic diagram of a chemical crystallization circulating granulation fluidized bed system in the utility model.

[0015] Figure 3 It is a flow chart of the implementation method of the utility model. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0017] In the description of the embodiments of the present utility model, it should be noted that if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate an orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, it is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0018] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components must be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0019] In the description of the embodiments of the present invention, "multiple" means at least 2.

[0020] In the description of the embodiments of the present utility model, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0021] Example:

[0022] Combined with Figure 1 The present embodiment discloses a chemical crystallization circulating granulation fluidized bed structure, comprising a cylinder 1, in which a water distribution area 101, a drug distribution area 102, a granulation area 103 and a clear water area 104 are sequentially arranged from bottom to top, and the water distribution area 101, the drug distribution area 102, the granulation area 103 and the clear water area 104 are respectively connected by circulating water pipes, the inlet end of the water distribution area 101 is connected to a water inlet pipe 2, the outlet end of the clear water area 104 is connected to a water outlet pipe 3, and the drug distribution area 102 is connected to an external drug adding pipe 4; the granulation area 103 is divided into three areas from bottom to top, the bottom of the granulation area 103 is a fluidizing area 103a, the top is a separation area 103b, and the middle is a static settling area 103c; the inlet end of the fluidizing area 103a is connected to an external seed adding pipe 5, and the outlet end is connected to a particle discharge pipe 6.

[0023] Combined with Figure 2 A chemical crystallization circulating granulation fluidized bed system comprises a circulating granulation fluidized zone A, a sludge concentration zone B, a sludge separation zone C and a water collection zone D which are connected in sequence, wherein the water collection zone D is connected to the sludge concentration zone B through a return pipe; a plurality of groups of cylinders 1 are arranged in the circulating granulation fluidized zone A, a plurality of sludge concentration fluidized beds are arranged in the sludge concentration zone B, a plurality of solid-liquid separation fluidized beds are arranged in the sludge separation zone C, and an outlet of the sludge concentration fluidized bed is connected to an inlet of the solid-liquid separation fluidized bed.

[0024] Combined with Figure 3 When used in practice, the implementation method includes the following steps:

[0025] (1) High-hardness water enters the water distribution area 101 of the cylinder 1 through the water inlet pipe 2, and enters the drug distribution area 102 through the circulating water pipe. The external drug adding pipe 4 adds alkali to the drug distribution area 102, including adding NaOH or Na2CO3, so that the Ca in the high-hardness water in the drug distribution area 102 is reduced. 2+ Mg 2+ The ions undergo a chemical reaction to generate CaCO3 / MG(OH)2 crystals; the generated CaCO3 / MG(OH)2 crystals enter the granulation area 103 through the circulating water pipe;

[0026] (2) The external seeding pipe 5 adds seeds into the granulation zone 103, and the seeds circulate among the fluidized zone 103a, the static settling zone 103c, and the separation zone 103b of the granulation zone 103, so that CaCO3 / MG(OH)2 crystals adhere to the surface of the seeds, thereby reducing the hardness of the water. The particles formed by granulation settle to the bottom in the fluidized zone 103a and are finally discharged from the particle discharge pipe 6 to the sludge concentration zone B, and the generated CaCO3 is recycled;

[0027] (3) The water treated in step (2) enters the clean water area 104 and is discharged to the regulating water tank through the outlet pipe 3. A softener is added to the regulating water tank, including adding H2SO4 or HCL, or adding CO2 to soften the water therein. The softened water enters the drinking water equipment;

[0028] (4) The sludge concentrating fluidized bed in the sludge concentrating zone B concentrates the incoming mixed water. The concentrated water enters the sludge separation zone C for sediment separation. The separated water enters the water collection zone D for collection. At the same time, the water in the water collection zone D returns to the sludge concentrating zone B through the return pipe for repeated treatment.

[0029] 1. Main achievements and technical performance indicators

[0030] According to the preliminary design of Kesu City Wastewater Treatment Plant and the actual water consumption in recent years, a deep water treatment workshop was built on the north side of Kesu City Wastewater Treatment Plant. The system consists of a 5000m 3 It consists of a water storage tank with a capacity of 1000 m3, 2 crystallization granulation fluidized beds, 3 solid-liquid separation fluidized beds and a supporting chemical dosing system. The system has a designed processing capacity of 700 m3 / h, the total hardness of the effluent is less than 200 mg / L (can reach 120 mg / L in actual operation), and the turbidity is less than 5 NTU. The treated water enters the factory through the water supply pipeline as production water.

[0031] 1. Economic benefits

[0032] (1) Before the construction of the deep water treatment system, production water was mainly taken from surface water. After the construction, the surface water consumption can be reduced by 2.5 million m 3 , water cost saving = 2.5 million m3 × 0.7 yuan / m3 = 1.75 million yuan.

[0033] (2) The calcium carbonate particles generated during the operation of the crystallization granulation fluidized bed have a diameter of 1-2 mm and a calcium carbonate content of more than 95%. They can be used as raw materials for the desulfurization system. 50 tons of calcium carbonate are generated each year, which is equivalent to 100 tons of limestone raw materials, saving 100 tons × 100 yuan / ton = 100,000 yuan.

[0034] 2. Environmental benefits

[0035] (1) There are not enough enterprises to reuse the reclaimed water from the Aksu sewage treatment plant, and the treated reclaimed water cannot be fully recycled, which has always been a problem for the sewage treatment plant. After the construction of the reclaimed water deep treatment system, it can absorb 2.5 to 3.5 million tons of reclaimed water each year, effectively consuming reclaimed water and helping the local government to solve the problem of insufficient reclaimed water to a certain extent.

[0036] (2) Previously, the Aksu City Wastewater Treatment Plant mainly used surface water from the Xixi Lake in Aksu City for production water, with an annual water intake of 2.5 million tons. After the deep treatment of reclaimed water is completed, the amount of surface water intake can be reduced by 2.5 million tons, which is more conducive to water conservation and ecological protection.

[0037] 3. Safety benefits

[0038] After the deep treatment system of reclaimed water was put into operation, the hardness of the treated reclaimed water was low, and the scaling rate of cooling tower fillers and condenser tube bundles was significantly reduced. The removal rate of raw water hardness by crystallization and granulation reached more than 70%, and the raw water hardness was reduced from 400mg / L to 120mg / L, which was better than meeting the water quality requirements of power plant production water, effectively reducing the hardness, and significantly reducing the scaling of condensers, heat exchangers, and cooling tower fillers. The cooling effect was improved, the workload of equipment operation and maintenance was reduced, and the service life was extended.

[0039] 4. Performance indicators

[0040] (1) The output of the reclaimed water deep treatment system is 700m3 / h, which can meet the production water demand of the power plant.

[0041] (2) The system has a high processing load, the water inlet flow rate can reach 60-100m / h, and the footprint is small. A single device with a diameter of 2000mm can process up to 300m 3 / h; The equipment workshop has a size of 48m×16m, with a total area of ​​768 square meters, which can be used to install a 1000m3 / h reclaimed water treatment system, consisting of three crystallization and granulation circulating fluidized beds and four solid-liquid separation fluidized beds and supporting chemical storage rooms and duty rooms.

[0042] (3) Water quality has a wide range of applications and strong impact resistance. It can be widely used in water treatment projects under various conditions. It has a good treatment effect on high turbidity water (up to 20,000 NTU) and low-temperature and low-turbidity water (down to 3 NTU), and has strong water impact resistance. It has a high removal rate of suspended solids and colloids, and stable effluent. It has a high removal efficiency for colloidal and suspended pollutants in water, and the effluent turbidity can reach below 5 NTU, and the effluent effect is stable.

[0043] (4) The sludge has low moisture content and is easy to handle. The moisture content of the discharged sludge is only 90%-95%, which is very convenient for subsequent sludge dehydration treatment.

[0044] (5) The organic matter content can be effectively reduced by adding activated carbon to the solid-liquid separation device.

[0045] The utility model has the advantages of less chemical agent addition, less waste generation, high hardness removal rate, small equipment footprint, less operation and maintenance workload, stable effluent quality, no wastewater generation, etc., especially the hardness removal rate of more than 70% is very impressive, and has great advantages over the traditional lime softening technology, and is very suitable for the softening treatment of various high-hardness water, such as recycled water (recycled water), industrial circulating water, mine drainage water, municipal tap water and various production enterprises that implement zero wastewater discharge.

[0046] The above description of the utility model and its implementation methods is not restrictive. The drawings show only one implementation method of the utility model, and the actual structure is not limited thereto. In short, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention of the utility model, they should all fall within the protection scope of the utility model.

Claims

1. A chemical crystallization circulating granulation fluidized bed structure, characterized in that: It comprises a cylinder body, in which a water distribution area, a drug distribution area, a granulation area and a clear water area are sequentially arranged from bottom to top, and the water distribution area, the drug distribution area, the granulation area and the clear water area are respectively connected by circulating water pipes, the inlet end of the water distribution area is connected to a water inlet pipe, the outlet end of the clear water area is connected to a water outlet pipe, and the drug distribution area is connected to an external drug adding pipe; the granulation area is divided into three areas from bottom to top, the bottom of the granulation area is a fluidizing area, the top is a separation area, and the middle is a static settling area; the inlet end of the fluidizing area is connected to an external seed adding pipe, and the outlet end is connected to a particle discharge pipe.

2. A chemical crystallization circulating granulation fluidized bed system, characterized in that: It includes a circulating granulation fluidized zone, a sludge concentration zone, a sludge separation zone and a water collection zone which are connected in sequence, and the water collection zone is connected to the sludge concentration zone through a return pipe; a plurality of groups of cylinders as described in claim 1 are arranged in the circulating granulation fluidized zone, a plurality of sludge concentration fluidized beds are arranged in the sludge concentration zone, a plurality of solid-liquid separation fluidized beds are arranged in the sludge separation zone, and the outlet of the sludge concentration fluidized bed is connected to the inlet of the solid-liquid separation fluidized bed.

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