Installation diagram of frame mixer on site, JBK-1500 frame mixer, dosing mixing frame mixer

Technical Description of Du'an Environmental Protection Frame Blender:　　

1、 Frame mixer

The selection of a frame mixer based on the physical properties, capacity, and mixing purpose of different media can play a significant role in promoting chemical reaction rates and improving production efficiency. The frame mixer is generally used for mixing Congee like materials.

The frame mixer can be regarded as a deformation of the paddle mixer, with a relatively sturdy structure and a large amount of animal material to be stirred. If the shape of the bottom of such a mixer is similar to the shape of the lower head of the reaction vessel, it is usually called an anchor mixer. The diameter of the frame mixer is relatively large, usually taken from the inner diameter of the reactor2/3~9/10, 50~70r/min. When used for low viscosity liquids, the ratio of the blade diameter to the tank diameter of the anchor impeller is 0.7-0.9, and for high viscosity liquids it is 0.8-0.95. The speed is usually 10-50 r/min. The gap between the frame mixer and the reactor wall is small, which is conducive to the heat transfer process. When rotating rapidly, the liquid driven by the mixer blades brings the stationary layer down from the reactor wall; When rotating slowly, a mixer with a scraper can generate good heat conduction. This type of mixer is commonly used for heat transfer, crystallization operations, and mixing of high viscosity liquids, high concentration slurries, and settling slurries.

Anchor and frame mixers belong to the same category, collectively known as anchor frame mixers. In order to increase the mixing range and remove residues or liquid layers from the tank wall, the outer contour of the anchor frame mixer should be close to the inner wall of the mixing tank, and its bottom shape can also be elliptical, conical, etc. to adapt to the contour of the tank bottom. In order to increase the mixing range for high viscosity materials and improve the rigidity of the impeller, it is often necessary to add some vertical blades and crossbeams on the anchor and frame structures, which results in a variety of structural shapes for the anchor frame structure.

2、 The classification of propeller types can be roughly divided into:

Anchor type, elliptical frame type, cone bottom frame type, box type, anchor frame type, etc .

3、 Applicable viscosity

ApplicablecompareHigh viscosity is200-300Pa · s.

4、 Application Fields

Anchor frame mixers typically operate at low speeds and do not generate significant shear forces when mixing low viscosity liquids, making them unsuitable for liquids-Liquid and gas-liquid dispersion. On the other hand, this type of impeller moves at a high flow rate inside the tank, with horizontal swirling flow dominating and lacking good mixing uniformity. However, the flow velocity near the tank wall can achieve a higher heat transfer film coefficient than other impellers, making it commonly used for heat transfer and crystallization operations. In addition, due to the large diameter of the blade and its proximity to the bottom of the tank, it is also commonly used to stir high concentration slurries and precipitating slurries. It is also commonly used for stirring high viscosity fluids.

5、 Flow state

Horizontal circumferential flow at different heights.

6、 Structure

The connection method between the anchor frame mixer and the mixing shaft is similar to that of a paddle type, that is, one end of the impeller connected to the mixing shaft is made into a semi-circular collar, and then the two semi-circular rings of the two sides of the blades are clamped on the mixing shaft with bolts, while the blades and the mixing shaft are fixed with through shaft bolts. Due to the large external dimensions of the impeller, for ease of assembly and disassembly, most of the blades are connected by bolts, and only small ones are cast or welded. The impeller is mostly made of flat steel and angle steel. In order to improve the strength of the impeller, reinforced steel plates can also be used.

7、 Selection precautions:

When used for stirring high viscosity fluids, as the viscosity of the fluid increases, the flow inside the tank decreases, and the energy transmitted by the transmission device acts as friction between the impeller and the fluidThe proportion of (cutting) consumption increases. From the perspective of mixing effect, there is liquid exchange near the blades, but there is almost no mixing effect near the shaft. Using a deformed frame impeller (adding inclined blade crossbeams or vertical blades to the frame) can improve the situation, but it still cannot completely solve the problem. To achieve complete flow of high viscosity fluids, it is necessary to use impellers with forced liquid extrusion flow, such as helical impellers. However, compared with helical impellers, anchor impellers are cheaper. When the blade diameter and speed are the same, anchor frame agitators are only 2/3 of helical impellers. Therefore, for situations where the mixing effect is not particularly emphasized, anchor impellers are often used.

In special occasions, in order to eliminate the disadvantages of low shear force of anchor impellers and mixed dead zones near the shaft, a combination of frame impellers and multi-layer turbine impellers can be used to form a coaxial double circumferential mixer. At the same time, in order to take advantage of the close proximity of its blades to the tank bottom and wall to achieve higher heat transfer efficiency, a scraper can also be installed on the blades of the anchor impeller to continuously scrape off liquids that are prone to adhere to the tank wall.

8On site installation diagram of frame mixer

Frame mixer dosing reaction equipmentConstruction and working process:

The mixer is composed of an electric motor, a vertical reducer, a frame, a coupling, a main shaft, a slurry plate, and underwater bearings. When the electric motor is powered on and decelerated by the reducer, the torque is transmitted to the main shaft of the mixer through the coupling to drive the slurry plate to rotate, thereby stirring the liquid.