What is a Reaction Kettle

The reaction vessel is broadly understood as a stainless steel vessel with physical or chemical reactions. The structural design and parameter configuration of the vessel is based on the needs of different process conditions, and the design conditions, process, inspection and manufacturing and acceptance need to be based on relevant technical standards to achieve the heating, evaporation, cooling and low and high speed mixing and matching reaction functions required by the process. Pressure vessels must follow the standards of GB150 {steel pressure vessels} and atmospheric pressure vessels must follow the standards of NB/T47003.1-2009 {steel welded atmospheric pressure vessels}. The pressure requirements of the reaction process vary with the design requirements of the vessel. Production must be processed, tested and trial run in strict accordance with the corresponding standards. Stainless steel reactor According to different production processes, operating conditions, etc. are not the same, the design structure and parameters of the reactor are different, i.e. the structure style of the reactor is different and belongs to the non-standard vessel equipment.

The reactor is a comprehensive reaction vessel, which is designed according to the reaction conditions for the structural function and configuration of the reactor accessories. From the beginning of feeding - reaction - discharging are able to complete the pre-set reaction steps with a high degree of automation, with strict regulation of important parameters such as temperature, pressure, mechanical control (stirring, air blowing, etc.) and concentration of reactants/products in the reaction process. The structure generally consists of a kettle body, drive unit, stirring unit, heating unit, cooling unit and sealing unit. Corresponding auxiliary equipment: fractionation column, condenser, water divider, collection tank, filter, etc.

Reaction kettle materials are generally carbon manganese steel, stainless steel, zirconium, nickel-based (Hastelloy, Monel) alloys and other composite materials. Reaction kettles can be made of SUS304, SUS316L and other stainless steel materials. The stirrers are anchor type, frame type, paddle type, turbine type, scraper type, combined type, and the rotating mechanism can adopt cycloid reducer, stepless speed reducer or frequency conversion speed control, etc., which can meet the special reaction requirements of various materials. Sealing device can adopt mechanical seal, packing seal and other sealing structures. Heating and cooling can adopt jacket, half pipe, coil, Miller plate and other structures, and heating methods are: steam, electric heating, heat-conducting oil, in order to meet the process needs of different working environments such as acid resistance, high temperature resistance, abrasion resistance and corrosion resistance. And it can be designed and manufactured according to the user's process requirements.

Classification

1、According to the heating/cooling method, it can be divided into electric heating, hot water heating, heat-conducting oil circulation heating, far-infrared heating, external (internal) coil heating, etc., jacket cooling and coil cooling inside the kettle, etc. The choice of heating method is mainly related to the heating/cooling temperature required for the chemical reaction and the size of the heat required.

2. According to the material of the kettle body, it can be divided into carbon steel reactor, stainless steel reactor and glass-lined reactor (porcelain-lined reactor), steel-lined reactor.

2.1、Carbon steel reactor

Scope of application: environment without corrosive liquids, such as certain oil processing.

2.2、Stainless steel reactors

1、Heating structure type

Electric heating type, jacketed type, outer half pipe type, inner coil type, volume 0.01m3～45m3

2、 Material

Carbon steel, stainless steel, high temperature resistant stainless steel, strong acid and alkali resistant stainless steel, enamel or PP material, etc.

3、Stirring type

Inclined slurry type, anchor type, frame type, propulsion type and single (double) spiral type, and other types of slurry leaves can be designed and manufactured according to customer requirements.

Applicable scope: It is suitable for petroleum, chemical industry, medicine, metallurgy, scientific research, universities and colleges to carry out high temperature and high pressure chemical reaction test, used to complete the process of hydrolysis, neutralization, crystallization, distillation, evaporation, storage, hydrogenation, hydrocarbonization, polymerization, condensation, heating and mixing, constant temperature reaction, etc. It can achieve high stirring effect on viscous and granular substances.

2.3、Glass-lined reactor

Scope of application: widely used in petroleum, chemical, food, pharmaceutical, pesticide, scientific research and other industries.

2.4、Steel lined PE reaction kettle

Scope of application: applicable to acids, alkalis, salts and most alcohols. Suitable for liquid food as well as and pharmaceutical refining. It is the ideal replacement of rubber lining, glass steel, stainless steel, titanium steel, enamel, plastic welding plate.

2.5、Steel lined PTFE reactor

It is resistant to various concentrations of acids, alkalis, salts, strong oxidizing agents, organic compounds and all other strong corrosive chemical media.

3、According to the internal pressure at work, it can be divided into normal pressure reactor, positive pressure reactor and negative pressure reactor.

4、According to the form of stirring, it can be divided into paddle type, anchor paddle type, frame type, spiral type, turbo type, dispersion disk type, combined type, etc.

5、According to the heat transfer structure, it can be divided into jacketed type, outer half-tube type, inner coil type and combined type.

Structure

The reaction kettle consists of the kettle body, cover, jacket, stirrer, transmission device, shaft sealing device and support. The stirring device is available with multiple stirring blades when the height and diameter are large, and can also be optional according to the user's requirements. A jacket is set outside the kettle wall, or a heat exchange surface is set inside the vessel, and heat exchange can also be carried out through external circulation. The support seat is available as a support or ear support, etc. Gear reducers are recommended for speeds over 160 rpm. The number of openings, specifications or other requirements can be designed and made according to user requirements.

1. Normally, packing seal is used under normal pressure or low pressure conditions, and the general use pressure is less than 2 kg.

2. In general medium pressure or evacuation situation will use mechanical seal, the general pressure is negative or 4 kg.

3. In the case of high pressure or high volatility of the medium will be used magnetic seal, the general pressure is more than 14 kg or more. In addition to the magnetic seal are used to cool down the water, other forms of seal in more than 120 degrees will increase the cooling water jacket.

Notes on use

Attention to use

A reaction vessel is a type of reaction equipment that must be operated with care, otherwise it can be damaged for many reasons, forcing production to stop. There are many aspects of reactor operation that should be noted.

Firstly, the reactor must be operated in strict accordance with the rules and regulations.

Secondly, before operation, check carefully whether there are any abnormalities. In normal operation, do not open the upper cover and touch the terminals on the board to avoid electric shock; it is strictly forbidden to operate with pressure; in the process of test pressure with nitrogen, observe carefully the changes in the pressure gauge and close the nitrogen valve switch immediately when the test pressure is reached; the speed of heating up should not be too fast, and the pressurisation should also be carried out slowly, especially the stirring speed, which is only allowed to rise slowly.

Finally, when the kettle is heated to a higher temperature, do not contact the kettle to avoid scalding; the experiment should be cooled down first. No quick cooling should be allowed to prevent damage caused by excessive temperature differential pressure. At the same time, the power supply should be unplugged in time.

At the same time the reactor should be maintained after use so that the autoclave can have a better service life.

Installation and operation specifications

1. The autoclave should be placed indoors. When equipping multiple autoclaves, they should be placed separately. Each operating room should have a direct exit to the outdoors or a passage, and the equipment should be well ventilated.

2. When fitting the lid, prevent the sealing surfaces of the kettle body and lid from knocking against each other. Place the cover carefully on the kettle body in a fixed position. When tightening the main nut, it must be tightened diagonally and symmetrically in several steps. Tighten the main nut diagonally and symmetrically several times. Use an even force and do not allow the cover to tilt to one side to achieve a good sealing effect.

3, positive and negative nut connection, only allowed to rotate positive and negative nut, two arc sealing surface shall not be relative rotation, all nut pattern coupling parts have assembly, should be coated with lubricant.

4、The needle type valve is a line seal, only need to gently turn the valve needle and press the cover tightly to achieve a good sealing effect.

5、Turn the rotary body on the kettle by hand to check whether the operation is flexible.

6、The controller should be placed flat on the operating table, its working environment temperature is 10-40℃, relative humidity is less than 85%, and the surrounding medium does not contain conductive dust and corrosive gas.

7, check the panel and back plate on the movable parts and fixed contacts are normal, draw open the upper cover, check whether the contact plug is loose, whether there is damage or rust caused by poor transport and storage.

8、The controller should be reliably grounded.

9、Connect all the wires, including the power supply line, the furnace line between the controller and the kettle, the motor line and the temperature sensor and the tachometer wire.

10、Close the "power" air switch on the panel and the digital display should show.

11. Set various parameters (e.g. upper alarm temperature, working temperature, etc.) on the digital display table and then press the "heating" switch to turn the furnace on. Adjust the "regulating" knob to adjust the heating power of the electric furnace.

12、Press the "stirring" switch, the stirring motor is energized, while the indicator light on the "stirring" switch is on, slowly turn the "speed" knob to make the motor rotate slowly, observe whether the motor If there is no mistake, stop the machine and hang up the belt, then restart it.

13、After the operation, it can be cooled naturally, by water or placed in the air cooling bracket. After the temperature has dropped, release the pressurised gas in the kettle and lower the pressure to normal pressure (the pressure gauge shows zero), then loosen the main nut symmetrically and equally, then remove the main nut and carefully remove the kettle cover and place it on the stand.

14. After each operation, the residues on the kettle body and lid should be cleared. The main seal opening should be cleaned frequently and kept clean, wiping with hard objects or surface roughness is not allowed.

Maintenance

(1) Installation: The reactor should be installed in a high-pressure operation room that meets the requirements of explosion-proof. When equipping more than one reactor, they should be placed separately, and a safe explosion-proof wall should be used to separate between each two units, and each operation room should have access and exit to the outdoors.

(2) After opening the package, check if the equipment is damaged, install the equipment according to the structure according to the equipment type, and check all the parts according to the packing list. If the heating method is heat-conducting oil electric heating, please purchase the appropriate type of heat-conducting oil according to the use of temperature (Note: heat-conducting oil is absolutely not allowed to contain moisture) to join, join the upper part of the jacket refueling port open and the jacket in the upper part of the oil level port open. Add oil through the oiling port and wait until the oil level port is flowing; then screw the oil level port to death, do not screw the oiling port to death to avoid pressure.

(3) Installation and sealing of the kettle body and lid: The kettle body and lid are gasketed or tapered with a line contact with the circular surface, so that they can be pressed against each other by tightening the main nut to achieve a good sealing effect. When tightening the nut, it must be symmetrical diagonally and tightened gradually for several times with even force, without allowing the kettle cover to tilt to one side to achieve a good sealing effect. When tightening the main nut, do not exceed the specified tightening torque of 40~120N.M to prevent the sealing surface from being crushed or overloaded and worn out. The sealing surface should be especially cared for. Before each installation, wipe the upper and lower sealing surface with a soft paper or cloth, paying special attention not to touch the sealing surface of the kettle body and cover to make scars. If operated reasonably, it can be used more than ten thousand times. If the sealing surface is damaged, it must be reworked and repaired to achieve a good sealing performance. When dismantling the lid, lift the lid up and down slowly to prevent the sealing surfaces between the body and lid from colliding with each other. If the seal is made of gaskets (teflon, aluminium, copper, asbestos, etc.), a good seal can be achieved by tightening the main nut.

(4) The installation of valves, pressure gauges and safety valves can be sealed by tightening the front and back nuts. The circular sealing surfaces of the two ends of the coupling must not be rotated relative to each other, and all screwed couplings must be coated with lubricant or graphite tempered with oil when assembling, so as not to bite. The use of valves: needle valve system line seal, only need to gently turn the valve needle, press tight cover that can achieve good sealing performance, prohibit excessive force, so as not to damage the sealing surface.

(5) After the installation of the equipment, through a certain amount of nitrogen pressure for 30 minutes, check whether there is a leak, if you find a leak, please use soap foam to find the pipeline, orifice leakage point, find out after releasing the gas tightening, again through the nitrogen pressure test, to ensure that there is no leakage after the start of normal work.

(6) When cooling down, use water to cool the kettle via the cooling coils. When the temperature inside the kettle exceeds 100℃, the water jacket between the magnetic stirrer and the kettle cover should be connected with cooling water to ensure that the water temperature is less than 35℃ to avoid demagnetisation of the magnet.

(7) Safety device: use positive arch type metal bursting disc, material is stainless steel, according to the national standard GB567-89 "arch type metal bursting technical conditions" manufacture, factory has been tested well, shall not be adjusted at will. If it has burst, need to be replaced, the replacement period by the use of the unit according to the actual situation of the unit to determine, for more than the rupture disc calibration burst pressure and not burst should be replaced, often use the best not more than 80% of the lower pressure of the rupture disc, replacement should pay attention to the convex side of the rupture disc up.

(8) After the reaction is finished, cool down the kettle first, then vent the gas inside the kettle to the outside through the pipeline, so that the pressure inside the kettle is reduced to normal pressure.

(9) Cleaning of the kettle: After each operation, use cleaning solution (care should be taken to avoid corrosion of the main material when using cleaning solution) to remove the residues from the kettle body and sealing surface, which should be cleaned frequently and kept clean.