Agitator sealing

Loss of sealing fluid for vessel agitator seal. Possible seal failure and emission of flammable or toxic vapors. 

For batch operations, introducing solenoid valves in water scrubbers, direct contact condensation and the flushes used to protect pump and agitator seals, such that if the operation is not in use, the flow of water is stopped. 

When used for dedicated production, maintenance is minimal. The agitator sealing system (usually a stuffing box or mechanical seal), however, must be maintained. 

What if reactor agitator seal fails. VCM fume release. Indicated by high pressure in the reactor seal and fume detector in the area. VCM fumes are flammable. Additional ventilation around reactor seal. Depressurize reactor on high seal pressure - SIS. Use LOPA to determine required SIL ... 

Reactor agitator seal fails Seal failure can lead to dangerous VCM fume release High Pressure in Reactor Seal Fume Detection in Reaction Area Additional ventilation around seal Depressure reactor on high seal pressure (SIS)... 

If the agitator seal pressure is greater than 10 psig open 100PV and 100PV-1. The required SIL = 2 (PFD = 10 to 10 )... 

Mercury-sealed stirrers are used in the following operations (1) simultaneous stirring and refluxing of a reaction mixture (2) stirring the contents of a closed vessel (3) agitation with prevention of the escape of a gas or vapour and (4) stirring in an inert atmosphere, such as... 

Continuous-Flow Stirred-Tank Reactor. In a continuous-flow stirred-tank reactor (CSTR), reactants and products are continuously added and withdrawn. In practice, mechanical or hydrauHc agitation is required to achieve uniform composition and temperature, a choice strongly influenced by process considerations, ie, multiple specialty product requirements and mechanical seal pressure limitations. The CSTR is the idealized opposite of the weU-stirred batch and tubular plug-flow reactors. Analysis of selected combinations of these reactor types can be useful in quantitatively evaluating more complex gas-, Hquid-, and soHd-flow behaviors. 

Develop alternative agitation methods to eliminate shaft seal as a potential hot spot Train operators to visually check mechanical seal fluid on regular basis Inert vapor space... 

I. The Hershberg stirrer, shown in part in Fig. 2, provides very efficient agitation of this or other pasty mixture. Two glass rings are sealed to the end of a stirrer shaft at right angles to one another, and each is threaded with B. and S. No. 18... 

The seleeted seale-up rule is applied to determine the agitator speed N2 from the equation ... 

Standard components for a bioreactor comprise the vessel, the agitator and impeller, heat exchangers, seals, and valves. Other components include utilities such as clean-in-place (CIP), and steam-in-place (SIP) systems, auxiliary tanks, pH and foam control, inlet tubes,... 

Empirieal dimensionless group eorrelations have been used in the seale-up proeess. In partieular, the eorrelation for the inside film heat transfer eoeffieient for agitated, jaeketed vessels has been employed for the seale-up to a larger vessel. Reaetion ealorimeters are often used to give some indieation of heat transfer eoeffieients eompared to water in the same unit. Conelation for plant heat transfer is of the general form... 

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