Jacketed vessels agitation

Equipment, The reactor was 1.523 liter, 316 stainless steel cylindrical, jacketed vessel equipped with two multiblade, paddle-type agitators. Tracer studies showed the reactor was well-mixed. A thermocouple measured temperature and was recorded continuously. Feed tanks, tubing, pumps and valves were made of stainless steel and had teflon seals. 

A solution of NaOH in water is prepared by diluting a concentrated solution in an agitated, jacketed, vessel. The strength of the concentrated solution is 50 per cent w/w and 2500 kg of 5 per cent w/w solution is required per batch. Calculate the heat removed by the cooling water if the solution is to be discharged at a temperature of 25°C. The temperature of the solutions fed to the vessel can be taken to be 25°C. 

Reactors, columns and other vessels are usually designed as special items for a given project. In particular, reactor designs are usually unique, except where more or less standard equipment is used such as an agitated, jacketed, vessel. 

Figure 12.72. Jacketed vessels, (a) Spirally baffled jacket (b) Dimple jacket (c) Half-pipe jacket (d) Agitation...

They were also used as colloiding agents for NC(Refs 2, 3 4) employed in the manuf of smokeless propellants. For instance, one of the US shot-gun propellants was prepd by agitating at RT(in a jacketed vessel) a pulped, wet NCfcontg 5% Ba nitrate 2% K nitrate) with an emulsion of amyl acetate and waterfcontg some Ba- and K nitrate). 

After allowing to stand for a few minutes, the steam was turned into the jacket and agitation continued for 5—6 hours during which time most of the amyl acetate and some water were distilled off. The contents of the vessel were then run out and the grains of propellant dried and sieved(Ref 3) Refs l)Beil 2,131-2,(60-1) [143-4] 2)Marshall 1(1917),336 3)Bamett(19I9),82... 

Agitated jacketed vessel the main resistance to heat transfer is located at the wall, where there is practically no resistance to heat transfer inside the reaction mass. Due to agitation, there is no temperature gradient in the reactor contents. Only the film near the wall presents a resistance. The same happens outside the reactor in its jacket, where the external film presents a resistance. The wall itself also presents a resistance. In summary, the resistance against heat transfer is located at the wall. 

Empirical dimensionless group correlations have been used in the scale-up process. In particular, the correlation for the inside film heat transfer coefficient for agitated, jacketed vessels has been employed for the scale-up to a larger vessel. Reaction calorimeters are often used to give some indication of heat transfer coefficients compared to water in the same unit. Correlation for plant heat transfer is of the general form... 

Sealed containers of aqueous solutions, suspensions, and other liquids can be processed through steam sterilizers as well. These liquids might be used in formulation or cleaning procedures, and sterilization in this manner may be more efficient and more reliable than sterilizing filtration. Larger volumes of aqueous liquids are often sterilized in bulk using a jacketed and agitated pressure vessel (the vessel is usually rated for full vacuum as well). 

Based on initial heat flow calorimetry studies, a process development engineer must choose the appropriate reactor vessels for pilot plant studies. A pilot plant typically has vessels that range from 80 to 5000 L, some constructed of alloy and others that are glass lined. In addition some vessels may have half-pipe coils for heat transfer, while others have jackets with agitation nozzles. A process drawing for a typical glass-lined vessel is shown in Figure 4. In Sections 3.1.4.1 and 3.1.4.2 we review fundamental heat transfer relationships in order to predict overall heat transfer coefficients. In Section 3.1.4.3 we review experimental techniques to estimate heat transfer coefficients in process vessels. 

In summary, because of the uncertain effect of system geometry, it is recommended that for purposes of estimation or design Table VI should be used to select a correlation which was developed from tests on a system as similar as possible to the one under consideration. For jacketed vessels using paddle agitators the correlation of Pursell is indicated. For other jacketed vessels or for the case of helical coils... 

Fluid Inside Fluid In Jacket Vessel Wall Material Agitation u... 

The solid wall can be the wall of the evaporator itself, as in jacketed evaporators. The area available for heat transfer in jacketed vessels, however, is quite limited. Jacketed vessels frequently incorporate some sort of internal agitator. 

A solution of NaOH in water is prepared by diluting a concentrated solution in an agitated, jacketed vessel. The strength of the concentrated solution is 50% w/w, and... 

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