The agitator is one of the core components of the reaction kettle. Selecting the corresponding agitator based on the physical characteristics, volume, and stirring purpose of different substances in the kettle can greatly promote the rate of chemical change and improve productivity.
Grasp the classification of the blender and the available places will help to choose the right blender, so as to reflect the actual effect better, learn from the web editor!
Application of reaction kettle
The reaction kettle is widely used in crude oil, chemical plants, vulcanized rubber, fertilizers, dyes, pharmaceuticals, foods, etc., and is used for the entire process of vulcanized rubber, nitrification, esterification, hydrocarbonation, polymer, condensation reaction and other processing processes container.
Composition of the reactor
The reaction kettle is composed of a kettle body, a kettle lid, a collet, a stirrer, a gear transmission, a water pump sealing device, a support plate and the like.
Electric heating sink reactor
1 cover of reaction kettle
The cover is composed of a ring-shaped head, a top cover and a lower stainless steel head. There are two ways to connect the top cover and the head. One is that the outer cover and the head are immediately welded to form a whole; the other is that it can be connected by flanges in consideration of convenient disassembly and assembly. The top cover is opened with many manholes, manholes and processing technology docking.
2 Reactor stirring equipment
In the reaction kettle, in order to accelerate the reaction time, improve mixing, and enhance the actual effect of convective heat transfer or heat conduction, the reaction kettle is generally equipped with stirring equipment. The utility model is composed of a stirrer and a stirring shaft, and is connected with a gear transmission into a whole by a coupling.
3 Sealing equipment of reaction kettle
The sealing equipment used in the reaction kettle has a dynamic sealing structure, and the key includes two types of packing sealing and mechanical sealing.
Classification and model selection of reactor agitator
The effectiveness of the reactor stirrer
It mixes and mixes raw materials uniformly, strengthens heat conduction and convective heat transfer, including homogeneous liquid mixing; liquid-liquid dispersion; gas-liquid dispersion; solid-liquid dispersion; crystals;
Structure of the reactor stirrer
Electric heating sink reaction kettle basic principle
The agitator is a key component to maintain the actual operation of the agitation. Its key component is the centrifugal impeller, which releases the mechanical kinetic energy to the liquid along with the arc fitness exercise and promotes the liquid fitness exercise.
When the agitator rotates, the mechanical kinetic energy is transmitted to the fluid, which creates a sufficient mixing zone with high turbulence around the agitator, and causes a rapid water jet to promote the circulation of the liquid in the agitator vessel car.
Factors Affecting Reaction Stirring
The way in which liquid flows in the circulation system within the category of machinery and equipment is called the "flowing solid model" of liquid, and it is commonly called "flow pattern".
The flow pattern is closely related to the actual effect of stirring and the output power of stirring. The flow pattern lies in the mode of the agitator, the geometric characteristics of the agitator vessel and the internal prefabricated components, and its fluid characteristics and the speed ratio of the agitator.
The direction of fluid flow is parallel to the agitating axis. The fluid is promoted by the paddles to make the fluid flow downwards, and then touch the bottom of the vessel to turn up, resulting in left and right circulation system flow.
The direction of fluid flow is bisecting the stirring axis vertically and flowing in the axial direction. When the boundary layer of the vessel is encountered, the fluid is divided into two streams, which flow upward and downward respectively, and then return to the leaf end without flowing over the leaf, resulting in two upper and lower circulation system flows.
In a vessel without partitions, the fluid rotates around the axis for fitness exercises. When the water flow is high, the surface of the liquid will vortex. The total flow of fluid that is drawn from the periphery of the blade to the blade area is not large, and the actual effect of mixing is poor. .
The three flow patterns generally exist separately; the mixing of radial flow and axial flow plays a key role; radial flow should be inhibited in many ways-the use of partitions can weaken radial flow and improve radial flow and axial flow .
Classification of reactor stirrers and available places
Paddle-type, push-type, pressure-type and anchor-type agitators are widely used in agitation reaction equipment, and according to surveys, they account for about 75 to 80% of the number of agitators.
1 paddle mixer
Consists of paddles, keys, collars, and vertical shafts. Paddles are generally manufactured from galvanized flat steel or stainless steel plates or rare metals. The speed of the paddle agitator is relatively low, generally 20 ~ 80r / min. The diameter of the paddle agitator is taken from the nominal diameter of the reaction kettle Di / 3 ~ 2/3. The paddles are not suitable for being too long. When the diameter of the reactor is quite large, two or more paddles are used.
The paddle agitator is suitable for liquid raw materials with large fluidity and low viscosity, as well as fiber and crystalline melting liquid. When the raw material layer is deep, several rows of paddles can be installed on the shaft. Folding blade type has less power than vertical blade type, and the actual operation cost is low.
Paddle agitators should not be used in practice to maintain vapor and gas-liquid dispersion for the purpose of miniaturization.
The push-type agitator should circulate the raw materials in the reactor car while stirring. The function is dominated by the capacity circulation system, the cutting effect is small, and the actual effect of rolling left and right is excellent. When greater water flow is necessary, a drainage cylinder is set up in the reactor.
The standard pusher type agitator has three leaves, the pitch of which is the same as the diameter d of the paddle. The diameter of the pusher stirrer is 1/4 ~ 1/3 of the nominal diameter Di of the reaction kettle, 300 ~ 600r / min. The raw materials of the stirrer are usually pig iron and cast steel.
Characteristics of pusher mixer:
Radial flow agitator; large circulation system, small agitation output power; simple structure, convenient production and manufacturing; common in low viscosity fluids.
3 booster type agitator
The speed of the booster agitator is very large, 300 ~ 600r / min. Straight and curved blade booster mixers cause axial flow, while folded blade booster mixers cause radial flow.
The key advantage of the booster mixer is that when the calorie consumption is not large, the mixing efficiency is high, and the mixing results in a strong axial flow. It is therefore suitable for emulsions, liquids, etc.
4 Anchor Agitator
Applicable for fluids with a viscosity below 100Pa · s. When the viscosity of the fluid is between 10 ~ 100Pa · s, a horizontal paddle can be added in the middle of the anchor paddle, which is a strip stirrer to improve the mixing in the middle of the vessel.
Features of Anchor Agitator:
Simple structure, convenient production; suitable for raw materials with large viscosity and large output; easy to obtain large surface thermal conductivity; can reduce the cause of "wall hanging".