The stirrer is one of ®©Ωthe key components of the reactor. Cho≥★♠♦osing the appropriate stirrer accordin<♠δg to the physical properties, capacity and ≤©stirring purpose of different media in the kett££÷le can play a great role in promoting the speed ✔™of chemical reaction and im≤‍♦proving the production ef₩>‍§ficiency.

　　Mastering the classification aπ​nd application of stirrer can help toσ  choose the right stirrer and achieve better γ≥"reaction effect!

　　I. Application of reactor

　　Reactors are widely use↑✘≠Ωd in petroleum, chemical, rubber€≠¥, pesticide, dyestuff, medicine, food,§¥γ♠ and are used to complete the p≤‍∞rocess of vulcanizationγ$↓​, nitrification, hydrogenation, hydrocarboniza♥ ✔≈tion, polymerization, condensation an₽₩↔d other pressure vessels.

　　Composition of reaction kettle

　　Reaction kettle is composed of kε ←ettle body, cover, j≤↑acket, stirrer, transmission device, shaft s∑∏ealing device, support, etc.

　　1. Shell of reaction kettle

　　The shell is composed of a round cyli¶¶ ¶nder, upper cover and lower head. There ar≈™δe two ways to connect the uppα€∞er cover with the barrel, one is to weld ≥π'€the cover and barrel directly to form a $∏whole; the other form is to consider the c"σonvenience of disassembly, available fl©♣ange coupling. The upper cover is opened with man ≤∞σhole, hand hole and process receiver.

　　2. Stirring device®Ω of reaction kettle

　　In the reaction kettle, in order ‌​×σto speed up the react∑€'ion speed, enhance th←₽≠₩e mixing and strengthen the mass transfe× ←r or heat transfer effect, the reactor is$•  generally equipped with stirring device."" It consists of stirrer and stirring↑" shaft, which is connected with the transmissionπ£Ω  device by coupling.

　　3. Sealing device of reactor

　　The sealing device used in the reactor•↕♠ is the dynamic sealing structur←∏e, there are mainly two kinds of packin×☆®g seal and mechanical seal.

　　C. Classification and selection

　　1. The role of reactor sti¥∞≤rrer

　　Mixing and homogenizing materials ≥≠≤, strengthening heat and mass transfer← , including homogeneous liquid mixing; liq<"uid-liquid dispersion; g​‌σas-liquid dispersion; solid-liqui★Ω•d dispersion; crystalliz¥Ω© ation; solid dissolution; strengthening heat t✔₩©₽ransfer, etc.

　　2. Reactor stirring principleγ& >

　　The main component of tα'∑πhe stirrer is the impeller, which moves wit>γ"h the rotating shaft to apply mechanical en★<₩ergy to the liquid and induce the liquiδ d to move.

　　When the stirrer rotates, t£↑♣βhe mechanical energy₹©×  is transferred to the fluid, forming a highly≠×γε turbulent and fully ✘Ωmixed area near the stirr→≈≈÷er, and generating a high-speed jet to push the l∞ iquid to circulate iΩφ¥n the stirred vessel.

　　Four, paddle stirrer

　　It is composed of pa≠↔↓→ddle, key, shaft ring and vertical s ≥♣☆haft. The paddle is generally ma☆≈≠↔de of flat steel or stainless steel × or non-ferrous metal. The rotational®≥   speed of paddle stirrer i↑©‌¶s low, generally 20~80r/min.

　　The diameter of the paddle stirrer •≥ is Di/3~2/3 of the inn ☆>¥er diameter of the react'•₹or. The paddle should notקφ• be too long, and two or more paddles ®₽$are used when the diameter of the r✘Ω→eactor is large.

　　Main applications: Paddle stirrer is su©‌™itable for liquid materials wi↔♥↑σth high fluidity and low viscosity, and als↓§>o for fibrous and crystalline dis$φ&solved liquids, and sevλ↑₽eral rows of paddles can be installed on th‍φ> e shaft when the material layer is deep. σγ''Folded blade type has≤≠Ω less power consumption and lower opλγε¶erating cost than the flat blade ±∞ε type, so the folded blade paddle is u$↔α∏sed more often.

　　Paddle stirrer can not be use←↑d in gas-liquid dispeσ₽♣rsion operation for the purpos✔€≤e of maintaining gas and fin♦Ω↕&e-tuning.

　　V. Propulsion type stirrer

　　Propeller stirrer can circulate the materia↑♠↔l in the reactor when stirε₽€Ωring, and the effect is mainlyβ♠ volume circulation, wit​♠δ≈h less shearing effect and good up and↔× down tumbling effect. When a larger flow©$ rate is needed, the reactor is equipped wit∑∞h a flow guide cylinder.

　　The standard propulsion st&®π∏irrer has three blades with a pitch eq♠©ual to the paddle di±∞★Ωameter d. The diameter "Ω$of the propulsion stirrer i♣≠♣s about 1/4 to 1/3 of the inner diameter Di of ×←$‌the reactor, 300 to 600r/min. The material o±♣§f the stirrer is often cast iron and c£™‌ast steel.

　　Sixth, turbine stirrer

　　The speed of turbine stirrer is large‍ε•r, 300~600r/min. The straight and∏≈α​ curved blade turbin>→Ωe stirrer mainly produces radial flow, aδ¥εγnd the folded blade turb™♣α≠ine stirrer mainly produces axial flow.

　　The main advantage of turbine stirrer i&←α‌s that when the energy consumption is not much, t™≥♦★he stirring efficiency is high and the st®​₩∏irring produces very s←↕trong radial flow. Therefo$§☆re, it is suitable for emulsio↓ δns, suspensions, etc.

　　VII. Anchor stirrer

　　It is suitable for mixing fluid with visc ±↔γosity below 100Pa-s. When the fluid vi∞₹scosity is 10~100Pa-s, a horizontal paddle>♠> can be added in the middle of the anch£←÷₹or paddle, which is ×‍∞a frame stirrer, to increase th‍≠$e mixing in the middle of t™♦®<he container.