1, concept,

　　Static mixer is a new type of advanced chemical unit equipment, since the 70 s, after the application is widely used in various fields at home and abroad rapidly. As is known to all, for the two strands of fluid mixing, generally use the method of mixing. This is a kind of dynamic mixing equipment, equipment in the moving parts. Main component static mixing unit inside the static mixer does not exercise in the process of mixing, but through the energy of the fluid itself and with the aid of static mixed cell have scattered mixed fluid equipment without moving parts.

　　2, the hybrid form of static mixer

　　Static mixer in the basic process of the combination of two types of methods as shown below. In practical application will often together using a variety of basic process. Two liquids together parts of the structure, should according to the liquid viscosity, density, mixing ratio, solubility, etc. Especially when two liquids contact reaction or gel and phase change, more attention should be paid to meet part of the structure, flow velocity and the choice of the mixer.

　　The mixture of laminar flow

　　After static mixer mixing of fluid mixed form, and the driving part of mixer or blender mixed hybrid form is an obvious difference. Figure 2 said the static mixer mix two kinds of typical laminar fluid is mixed state. Hybrid state by the belt into the continuous or discontinuous line and the particle shape, and the change of the state depends on the Reynolds number of fluid mixed and weber number. For example: when the flow velocity, viscosity, the diameter of mixer, certain if large surface tension between fluid and fluid mixing form from the belt to line, and then change to the particle shape. Mixer unit number, diameter and flow velocity of the selected unit number and diameter of mixer with the nature of the fluid (viscosity, solubility, density), the state of mixing, mixing ratio, desired, such as the contact surface of the liquid structure change and different, can be determine by experiments and experience. Usually mixer is determined based on the Reynolds number and the test of magnification. But when the Reynolds number Re < 100 (strictly speaking under 1), the degree of mixing, mixing state has nothing to do with Reynolds number, only depends on the unit number mixer. Therefore, as long as the mixing uniform fluid, regardless of their velocity and diameter of mixer, the number of unit test to determine. The mixer tube flow velocity, the greater the mixing effect is better. But the velocity is too large, the pressure loss increases, increases the pressure of the pump head and energy consumption. Therefore selected velocity has a more optimal range.

　　Turbulent mixing is suitable for the turbulent mixing of static mixer in the form of the twisted blade. The reason is that, with the increase of flow velocity in the section of the flow direction will produce a lot of fierce vortex and strong shear force. As a result of the existence of such a powerful shear force, it can effectively occurs gas-liquid and liquid-liquid and solid-liquid dispersion and dissolution of liquid liquid, solid and liquid.

　　In addition to the twisted blade form, other forms of static mixer can also be turbulent mixing, but its supply most of the energy of the fluid consumption in the fluid and wall friction, friction between the rarely used for fluid. So, from the point of view of energy consumption, the structure is inferior to the form of twisted blade of mixer.

　　3, the mixing mechanism of fluid

　　For a different occasions, such as laminar flow and turbulent flow in the static mixer fluid mixing mechanism of the difference is very big. Laminar flow is the "split the position of -- -- -- -- - to join" the three elements of fluid to have rule over and over again, so as to achieve mixed; Turbulence, in addition to the above three elements, the fluid in the section of the flow direction of eddy current, violently strong shear force for fluid, the fluid mixing part further divided.

　　4, static mixer has the following features:

　　(1) mixing performance is good, high efficiency, easy to realize continuous production, reduce the labor intensity, improve production efficiency;

　　(2) large elasticity of operation, stable operation;

　　(3) amplification effect is small, enlarge easy; Static mixer type, specification, the applicable scope is wide;

　　(4) simple in structure, equipment, small volume, cover an area of an area small, not easy to damage, equipment cost is low;

　　(5) low energy consumption, operation cost is small.

　　Mixed reaction technology

　　As a general rule, the static mixer without using mechanical mixing unit can be achieved. All kinds of material composition of the moving parts is limited to be mixed.

　　Product mix the required energy directly from the fluid itself, the mixture of fixed unit can continuously to cutting fluid, diffusion and redistribution. Mixed needed from the motion of the pump device.

　　In fact, the static mixer has small volume, convenient maintenance, simple installation, removable and high reliability.

　　All of the continuous process mass transfer industry by mixing and reaction technology.

　　5, application field

　　Static mixer development began in the early 70 s, in chemical, petroleum, chemical, oil, food and environmental protection and other fields has been applied gradually, and in as assigned by chemical unit operations, extraction, gas absorption, reaction, heat exchange, dissolved, dispersed, the respect such as powder, the mixture of aggregate is developing rapidly, and make effective use of the characteristics of mechanical and application system development constantly made gratifying achievements.

　　6, water treatment field

　　In the field of water treatment, mixing and contact is the most important unit operations, it will be a fundamental impact on the effect of various processing stages, even will affect the whole process of the final result. To improve the water quality requirements to continuously improve the purification process. Yes this online static mixer in the field of use (used for mixing and contact operation) are increased obviously.

　　Used for mixing and contact action of static mixer is installed in the process of the logistics pipeline. Related pipe or pipe can be round, square or rectangle. Different design and different materials use different mixer, so as to better meet all kinds of technical requirements.

　　6.1 features

　　Static mixer is mainly composed of orderly guide plate, and to guide plate made regularity of radial mixing material flows through a pipe. Flow approach has a certain geometry, therefore can be ruled out any random mix. Hybrid task so can be completed within very short flow distance.

　　With agitation tank or atc system, static mixer can ensure compulsory mixing contact on the liquid flow.

　　Hybrid or mass transfer the energy needed to independent fluid itself, for this performance relative to the atc system has a high pressure drop. Pressure drop value depends on the design of the mixer and related operating conditions, generally within the range of 0.02 3 MWG. Compared with dynamic mixer, static mixer the energy needed to power a small at least one order of magnitude. In addition, the energy can through the mixer volume evenly to dissipate.

　　6.2 features

　　Mixer unit length is very short of surface to surface (for 1 to 5 times the pipe diameter, therefore, the required installation space also is very small. Reinstall the device in general won't appear any problems. As a rule, the diameter of the mixer and the diameter of the connecting pipe are the same.

　　Even in the operating conditions under the condition of changing, mixing effect can remain stable. Such as flocculating agent, additives can be quickly and evenly spread out. There is no need for too much to feed materials (it has been proved can save up to 45%).

　　Mixer to compulsory mixing on the entire process of logistics. Thus can greatly reduce the grough, even without the use of reservoir.

　　Due to the fluid concentration on the whole section is a continuous and balanced, so has high representative.

　　Will soon start device. Run continuously for a stable state. Get representative data, thus to effectively control device.

　　Pressure drop and low energy consumption.

　　Static mixer has no moving parts. So there is no wear and tear, need maintenance workload is very small.

　　In installation and material of high flexibility. Static mixer section can be round, square or rectangle; Can also be installed in an open duct. The material of mixer can adopt stainless steel, carbon steel, PP, PVDF, or glass fiber reinforced plastic.

　　flocculation

　　As soon as possible in order to get the best flocculation effect of PAC, FeCl3, FeSO4 or polymer electrolyte distribution to the whole process of material flow. Through the use of the mixer can be ideal to achieve. Liquid forced mixer can ensure the whole logistics evenly mixed in seconds, medicament actual amount save up to 45%.

　　On-line dilution of flocculant

　　To make the flocculant has the best activity, before it joined the sewage, must use the volume for 10-100 times of water to dilute. Due to the primary solution in the general case for the high viscosity solution, don't automatically be diluted in water, so be sure to mix thoroughness. Polymers in water distribution more uniform, the activity. Using static mixer can ensure effective mixing. The use of static mixer can reduce the use amount of flocculant, so can save cost.

　　Mixed disinfectant

　　Rapid contact disinfection technology used in water treatment

　　Sodium hypochlorite in dissociated into HOCl and OCl - ion in aqueous solution, namely the effective free chlorine, which plays a role of main sterilization HOCl. After processing the residual organic matter in water and the generation of active chlorine compounds without sterilization ability. In order to give full play to the sterilization effect of HOCl, requirements after adding sodium hypochlorite before HOCl with organic reaction, complete disinfection effect quickly within a few seconds. Water treatment after adding the sodium hypochlorite disinfection, rapid contact is very important.

　　Static mixer

　　Static mixer choose simple structure of the spiral mixer, is installed in the pipe a certain number of left-handed right-handed components (see figure 1). After adding the sodium hypochlorite solution of the flow by static mixer has three kinds of hybrid effect:

　　(1) segmentation effect. Each element will flow in two, if mixer with six components, the flow is divided into 26 64 shares. Water is divided after the liquid layer thickness is very thin, the bacteria exposed to HOCl, increasing the contact area, easy to be exterminated.

　　(2) the transformation function (radial vortex reversal effect) flow within each section along the center of a tube eddy current reverse alternately, to enhance the contact.

　　(3) the reverse effect. In the mixer in the inland waters flowing through the right components and left-handed components of rotating in opposite directions alternating, raise the efficiency of contact.

　　7, the work scope of static mixer and the installation location

　　Static mixer has a wide scope of work. Used for liquid mixture, the static mixer general design for the fluid flow rate of 0.5 to 1.5 m/s. But even in the case of low flow rate, the mixer can obtain very good mixing effect. In most applications, mixing device can be installed in any position. If there is a big difference between the density of the medium to be mixed and the flow rate is very low, the mixer should be installed in a vertical position (flow direction is best for small first).

　　8, adjustable static mixer

　　Adjustable static mixer RSM is to apply the method of "change the internal space of tank volume" RST patent technology, for water treatment industrial design of a new type of high efficiency and energy saving of hydraulic machinery, pipeline mixing device.

　　RSM hybrid mechanism was a Rohud, no moving parts, it is anchored in the mixer, its work flow in static state relatively. In pipe flow driven by Rohud automatically a conical nozzle, the injection dispersive turbulent flow is still a typical pipeline static hydraulic hybrid model. Through differential pressure controller, automatic control system or manual operation, to adjust the spirit in the process of production of the size of the spray hole, in order to change injection flow rate, energy necessary to sustain the mixing process and the velocity gradient G values. RSM revolutionized the static mixer (fixed) can't control the disadvantages of hydraulic mixing intensity, for the first time the hydraulic pipeline mixing process can be controlled.

　　Widely used at home and abroad of various fixed pipeline static mixer is can't adjust, only in the production operation conditions and design parameters of mixer and the working conditions, to get to the stage of mixing effect. In waterworks flocculation mixing process, for example; In the process, the water quality of water, water temperature, chemical species and dosage is often change affecting flocculation effect. Such as production running water subject to increase or decrease of the total water consumption. At the beginning of the water plant put into production or winter water, present situation of operation under low load. In this case, the stationary state such as mixer mixing intensity severity shortage, lead to inferior coagulation sedimentation effect, drug consumption increased; Old factory, thus improving water rate and water supply during the peak summer is overload operation condition. Inevitably occur, because of the large mixer resistance head loss (energy) increased sharply, and the phenomenon such as waste of energy.

　　RSM is the main technical characteristics of regulatory, strong ability to adapt to the changing flow, to be able to produce the change of operating condition to react and adjust in time. If a season of good don't have to do this with mixed water quality conditions, the RSM of nozzle hole diameter can be adjusted to close to the level of the pipe diameter, unimpeded through water, eliminate the unnecessary energy consumption.

　　As is known to all, the defects of the fixed type static mixer is accepted, since there is no solution or alternative products, can only be run in spite of illness. If replace them by using RSM, will change the status quo, improve tap water, the technical quality of flocculation mixing process, to save reagent, save power and improve the purifying water quality and reduce production cost.

　　Adjustable static mixer, is improvements on original pipeline static mixer. As is known to all, static mixer in the water to meet the design conditions, has the very good mixing effect, but when water system efficiency low (below 80%) design, the decrease of strength of mixture, the effect of variation. We develop adjustable static mixer, can in the case of low water always ensure when design the best mixing effect, the minimum water can achieve 40%. Its large waterworks, especially suitable for the system of water change improved hybrid effect, for the subsequent process of flocculation and precipitation (or clarify) provide a good condition, which can also reduce drug consumption. Its implementation is simple, convenient operation, from the analysis on hybrid mechanism is there is no doubt that can achieve mixed regulation, has been through the pilot test, really can guarantee the mixing effect.

　　Realize the rapid and mixed water treatment process, the mixed flow mixing water flow is not accord with the requirement of fast and uniform mixing, push flow pipe, the effect of mixed depends on the flow of influence. In this paper, the author puts forward a kind of adjustable static mixer (RSM) is expected to break through the restriction of pipe flow, realizing fast mixing process of hydraulic control.