CN1522975A - A side stream treatment device and method for a small and medium-sized circulating cooling water system - Google Patents

Abstract

The invention discloses a side flow treatment device and method of a medium and small-sized circulating cooling water system. The device includes a housing, on which there are water inlets and outlets that can be connected to the circulating cooling water system in the form of bypass flow, and a filter unit is provided in the housing, and it is characterized in that there is a controlled release type under the filter unit. A dosing unit composed of a solid water treatment agent, the water outlet of the dosing unit is connected to the water outlet; the filter unit adopts fiber filter material. The treatment method is in the form of side flow, and the process includes the steps of adding coagulant for mixing, flocculation, filtering and automatically adding water treatment agent, and it is characterized in that the steps of filtering and adding water treatment agent are all completed in the filter, wherein , Adding water treatment agent automatically enters the filtered water through the dissolution of controlled release solid water treatment agent. It has the advantages of simple process, compactness, convenient operation, high flexibility, low operating cost, and no need for daily maintenance by professionals.

Description

A side stream treatment device and method for a small and medium-sized circulating cooling water system

technical field

The invention relates to a water quality treatment device and method, more specifically, a side stream treatment device and method suitable for small and medium-sized circulating cooling water systems with dual functions of water purification and automatic quantitative dosing.

Background technique

The open circulating cooling water system has the process of water concentration and water-air washing process, which increases the concentration of impurities in the water, which leads to the aggravation of the scaling tendency of the cooling water and the proliferation of microorganisms. For small and medium-sized circulating cooling water systems, on the one hand, the system itself has the characteristics of large load changes and high concentration ratios, making water treatment difficult; on the other hand, there are often lack of professionals for water quality monitoring and daily maintenance, and water quality cannot be standardized. , and some don't even do any processing. This phenomenon is especially common in the hundreds of thousands of central air-conditioning cooling water systems in major cities. The three major problems of corrosion, scaling and bacteria and algae reproduction not only cause the working efficiency of the refrigeration unit to decrease, the energy consumption increases significantly, but also endanger the refrigeration system. normal operation and shorten the service life of the equipment.

Conventional water quality stabilization technology and traditional water treatment agents have strict requirements on water quality monitoring, process operation and water treatment agent quality management. Among them, keeping the concentration of water treatment agents in cooling water within its effective range and controlling the content of harmful suspended solids, hardness and other impurities below the allowable concentration is an important part of water quality management, which often requires a lot of manpower and material resources , which increases the cost of water quality treatment and the burden of enterprises, has become the main factor limiting the effect of water treatment, and is also the main obstacle to the promotion and implementation of water quality treatment technology in small and medium-sized circulating cooling water systems. The existing side-stream treatment or sewage treatment methods often have the disadvantages of complex process flow, more equipment, inconvenient operation, etc., and it is difficult to meet the needs of small and medium-sized circulating cooling water systems.

The function of the side filter is to use an appropriate process to process the circulating cooling water, which can remove the harmful components that are increasing in the system and limit the water treatment effect, which is equivalent to regenerating the sewage as supplementary water and reusing it in the circulating cooling water system. This can further improve the reuse rate of industrial water, reduce the discharge of waste water, and basically realize the "zero discharge" of the system. It has the functions of water saving, energy saving and production cost reduction for industrial enterprises. Sustainable economic development is of great significance.

Filtration is the most commonly used side-stream treatment method, which can remove most of the suspended solids, slime and microorganisms in the water. Although it cannot reduce the hardness and salt content of the water, the concentration of impurities in the backwash water is much higher than that of the sewage in the circulating water. There are many, so a lot of impurities are discharged, and the amount of water consumed is very small. The side filter can significantly reduce the amount of sewage. In recent years, the application of fiber filters in the side-stream treatment of industrial circulating cooling water has attracted attention. But the existing fiber filter generally only has a single filtering function, such as the "fiber filter" disclosed in Chinese patent 02226483.3.

The controlled release technology of drugs has the advantages of saving dosage, prolonging the effective time of drugs, improving treatment effect, and reducing toxic and side effects. The controlled release of water treatment agent is used to realize the automatic and constant-speed dosing of water treatment agent, which is conducive to the stable control of the concentration of water treatment agent in the system, and can greatly reduce the workload of water quality monitoring and process operation. For example, polyphosphate, the dissolved product of phosphate controlled release glass (P-CRG for short) in water, has the effect of corrosion inhibition and scale inhibition, and at the same time it can become the carrier of inorganic antibacterial ions and release inorganic ions with bactericidal effect. Therefore, It has a good application prospect as a controlled-release solid water treatment agent.

Contents of the invention

The technical problem to be solved by the present invention is to provide an integrated side stream treatment device for small and medium-sized circulating cooling water systems with dual functions of coagulation filtration and automatic dosing, aiming at the above-mentioned current state of the art.

Another technical problem to be solved by the present invention is to provide a side-stream treatment method for small and medium-sized circulating cooling water systems with simple process flow, convenient operation and no need for daily maintenance by professionals.

The technical solution adopted by the present invention to solve the above-mentioned first technical problem is: the side flow processing device of this kind of small and medium-sized circulating cooling water system, which includes a shell, and the shell is provided with a side flow that can be connected to the circulating cooling water in the form of side flow. The water inlet and outlet of the system, the housing is provided with a filter unit, which is characterized in that a dosing unit composed of a controlled-release solid water treatment agent is provided under the filter unit, and the water outlet of the dosing unit is connected to the said dosing unit. Outlet.

A reaction space for the coagulation process is reserved above the filter unit.

The bypass treatment device of the medium and small-sized circulating cooling water system also includes a backwashing mechanism.

The filter unit is a filter layer made of fiber filter material; the fiber filter material can be fiber ball filter material or other granular fiber filter material.

The solid water treatment agent is a phosphate controlled-release glass ball with corrosion and scale inhibition effects; the diameter of the glass ball is preferably 1-200mm. The solid water treatment agent can also be particles of other irregular shapes, but preferably spherical.

The erosion release process of the solid water treatment agent has 0-order reaction kinetic release characteristics.

An orifice plate is arranged above the filter material layer to prevent the loss of the fiber filter material caused by backwash water.

The advantages of the device of the present invention are: 1, because the present invention uses the solid water treatment agent as the filling layer or support layer of the filter material layer, thereby realizing the combination of bypass coagulation filtration and bypass automatic dosing in the same device, with It has the characteristics of simple structure and compact equipment; 2. Combining the advantages of fiber filtration technology and controlled drug release technology, it has the characteristics of convenient operation, no need for professional maintenance, and great flexibility; 3. There is a space above the filter layer for mixing The reaction space of the coagulation process, the suspended solids in the water and the flocculant have a "micro-flocculation effect", and the floc particles generated can be removed through the deep layer and high-precision filtration of the fiber filter material, which has the advantages of high filtration accuracy, long operation period, and dirt holding capacity. Large quantity and other advantages.

The technical scheme adopted by the present invention to solve the above-mentioned second technical problem is: the side-flow treatment method of this kind of small and medium-sized circulating cooling water system, which treats the circulating cooling water in the form of side-flow, and its process includes adding coagulant and mixing , flocculation, filtration and automatic addition of water treatment agent steps, characterized in that the steps of filtering and adding water treatment agent are all completed in the filter, wherein the addition of water treatment agent is achieved through the dissolution of the controlled-release solid water treatment agent Automatically into filtered water.

The treated water volume of the side stream is 1-5% of the circulating water volume.

The flocculation step is also performed within the filter.

The filtering step is completed through the fiber filter layer.

The method of the present invention has the advantages of: 1. Since the steps of filtering and adding water treatment agent automatically and even the flocculation step of the method of the present invention are all completed in the same filter, it has the advantages of simple technological process, convenient operation, and no need for professionals to carry out daily Features of maintenance; 2. Low operating cost.

Description of drawings

Fig. 1 is technical process reference figure of the present invention;

Fig. 2 is a structural schematic diagram of the device of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

Example

As shown in Figure 1, it is a preferred embodiment of the method of the present invention. It adopts the form of side flow to process circulating cooling water, and the treatment water volume of side flow is 1-5% of the circulating water volume. The treatment process includes the steps of adding coagulant for mixing, flocculation, filtration and automatic addition of water treatment agent. Among them, the The above steps of filtering, flocculation and adding water treatment agent are all completed in the same equipment—the device of the present invention, and the addition of water treatment agent is automatically achieved through the dissolution of the controlled-release solid water treatment agent with the trade name "Xiugoujing". Enter the water that has been filtered, and filter it with a granular fiber filter layer.

As shown in Figure 2, it is a preferred embodiment of the device of the present invention. It includes a shell 1, which is provided with a water inlet 2 and a water outlet 3 that can be connected to the circulating cooling water system in the form of bypass flow, and a sewage outlet 4 for backwashing on the top of the shell 1, The housing 1 is provided with a filter unit composed of a fiber filter material layer 5, above which there is a reaction space 6 for the coagulation process, and below the fiber filter material layer 5 is a filter unit made of a product named rust. A dosing unit 7 composed of a clean controlled-release solid water treatment agent, the water outlet of the dosing unit 7 is connected to the water outlet 3 . In addition, an orifice 8 is provided above the fiber filter layer 5 to prevent the fiber filter from being washed away during backwashing; a supporting orifice 9 is provided below the device, and a backwashing air distribution and water distribution are installed above it. device, and filled with a 10-20mm quartz sand layer 10, on which is the phosphate controlled release solid water treatment agent "rust scale net"; in order to facilitate the understanding of the consumption of the glassy "rust scale net" 5 and the "rust clean" layer, a transparent observation mirror (not shown) is installed at the interface, and the bottom of the device is also provided with an air inlet 11 for backwashing.

The water treatment process and the backwashing process of the method of the present invention will be further described in detail below in conjunction with the device of the present invention.

1. Water treatment process:

As shown in Figure 1, the water in the cold water pool of the circulating cooling water system enters the circulating pipe through the circulating pump, most of it goes to the cooling tower after passing through the heat exchanger, and 1 to 5% of the circulating water enters the bypass water through a pipe In the treatment system, before the circulating cooling water entering the branch pipe enters the device of the present invention, a coagulant is first added through the jet, and after being mixed uniformly in the pipeline, it enters the device of the present invention and occurs in the reaction space 6 above the fiber filter material layer 5. "Micro-flocculation reaction", the floc particles generated by the coagulant and the suspended matter in the water, together with some CaCO ₃ and Ca ₃ (PO ₄ ) ₂ particles, and microbial slime are intercepted and removed by the fiber filter material, and the filtered water The turbidity can drop below 1NTU. With this method, part of the orthophosphate in the side filter water can be adsorbed and removed by the fiber filter material and the floc particles it retains.

When the filtered side-flow cooling water passes through the dosing unit 7, the "rust dirt net" water treatment agent dissolves into the water at a certain rate and releases polyphosphate with corrosion and scale inhibition effects to achieve constant speed dosing. The water returns to the cold pool. The appearance of the rust net is a glassy crystal ball, and its diameter can be 1-200 mm. In this embodiment, the diameter is about 80 mm. Under the conditions of temperature and medium, the dissolution rate of particles per unit surface area and the release rate of the active substances contained in them are constant. It has dual functions of corrosion inhibition and scale inhibition. It can be used as a long-term water treatment agent for automatic dosing. It has a small dosage, Low cost, no monitoring and other advantages. In order to realize the maximum simplification of the cooling water treatment process, it is suitable for small and medium-sized circulating cooling water systems managed by professional and technical personnel, and is an economical and effective water quality treatment method for small and medium-sized circulating cooling water systems and municipal water supply systems.

Second, the backwashing process:

When using air-water backwashing, air-water enters from the air inlet 11 at the bottom of the device of the present invention, and is evenly distributed on the bottom support orifice 9, and the particle fiber filter material is loosened under the impact of water-air, and in the upper space of the device Fluidization, swinging and scrubbing with the air flow; backwash liquid and air are discharged from the sewage outlet 4 on the upper part of the device through the sewage pipe. Under the action of air-water recoil, the glassy solid water treatment agent filling layer is also washed, but because its specific gravity is much larger than the fiber filter material, it can maintain the shape of the lower bed; the solid water treatment agent with small particles will also flow with the water. And the air flow rolls up and down, but after the backwashing is over, the stratification of the filter material can be easily achieved, creating conditions for the next round of water treatment.

Cost benefit analysis of the present invention:

The operating cost mainly includes the consumption of coagulant and the cost of rust water purification agent, plus the power consumption (mainly including the power consumed by the water inlet pump, backwash pump and Roots blower), the total cost can be controlled at 0.5 yuan Below / ^m3 , it is a more economical treatment method.

The benefits include saving water and sewage charges by increasing the concentration multiple, reducing the amount of supplementary water and sewage, reducing the consumption of water treatment agents, etc., as well as improving the effect of water quality stabilization, prolonging the service life of equipment, and improving heat transfer efficiency. Benefits; benefits generated by saving manpower, etc.

Process equipment features:

The process and treatment equipment have the characteristics of simple process, compactness, convenient operation, and great flexibility. It removes harmful components such as suspended solids, orthophosphate and microbial slime in industrial circulating cooling water at the same time, and supplements the active ingredient of polyphosphate at the same time. , to achieve the purpose of improving water quality, improving corrosion and scale inhibition effects.

Claims (12)

1. A side-flow treatment device for a small and medium-sized circulating cooling water system, which includes a shell, on which is provided a water inlet and a water outlet that can be connected to the circulating cooling water system in the form of side-flow, and a filter unit is provided in the shell , characterized in that a dosing unit composed of a controlled-release solid water treatment agent is provided below the filter unit, and the water outlet of the dosing unit communicates with the water outlet. 2. The side stream treatment device of a medium-sized and small-sized circulating cooling water system according to claim 1, wherein a reaction space for coagulation process is reserved above the filter unit. 3. The bypass treatment device of a medium-sized and small circulating cooling water system according to claim 1, characterized in that it also includes a backwashing mechanism. 4. The side stream treatment device of a medium-sized and small circulating cooling water system according to claim 1, 2 or 3, characterized in that the filter unit is a filter material layer made of fiber filter material. 5. The side stream treatment device of small and medium-sized circulating cooling water system according to claim 1, 2 or 3, characterized in that the solid water treatment agent is a phosphate controlled-release glass ball with corrosion and scale inhibition functions. 6. The side stream treatment device of the medium-sized and small-sized circulating cooling water system according to claim 1, 2 or 3, characterized in that the dissolution release process of the solid water treatment agent has 0-order reaction kinetic release characteristics. 7. The side stream treatment device of a medium-sized and small circulating cooling water system according to claim 4, characterized in that an orifice plate is arranged above the filter material layer. 8. The side-stream treatment device of a medium-sized and small circulating cooling water system according to claim 5, characterized in that the diameter of the phosphate controlled-release glass ball is 1-200mm. 9. A side-stream treatment method for small and medium-sized circulating cooling water systems, which treats circulating cooling water in the form of side-streaming, and the process includes the steps of adding coagulant for mixing, flocculation, filtering, and automatic addition of water treatment agent, its characteristics The steps of filtering and adding the water treatment agent are all completed in the filter, wherein the addition of the water treatment agent automatically enters the filtered water through the dissolution of the controlled-release solid water treatment agent. 10. The method for treating the side flow of the small and medium-sized circulating cooling water system according to claim 9, characterized in that the amount of treated water in the side flow is 1-5% of the amount of circulating water. 11. The side-stream treatment method of small and medium-sized circulating cooling water systems according to claim 9, characterized in that the flocculation reaction is also completed in the filter. 12. The side-stream treatment method of small and medium-sized circulating cooling water systems according to claim 9, characterized in that the filtering step is completed through a fiber filter layer.

Images