Semibatch Reactors with a Heat Exchanger

Analysis Runaway reactions arc the most deadly in the chemical industry. Elabci rate safety measures are usually installed to prevent them from occurring. However, as we show in this example, the back-up plan failed. // any one of the followinj three things had not occunvd. the explosion would not have happened. 

Unsteady-State Nonisotliennat Reactor Design Chapter 13 

Recall that at steady state dTfdt = 0), Equation (13-15) can be solved for the conversion X as a function of reaction temperature by recalling that 

Aqueous sodium hydroxide is to be fed at a cooceritration of I kmol/nP, a letnperatute of 300 K. and a voliimetric rate of O.OIM nrVs to an initial vdume of 02 m- ttf water and ethyl acetate. The concentration of water in the feed. Cwh is 55 kmol/m. The initial concentrations of ethyl acetate and water are 5 kmol/m and 30.7 kmol/ro respectively. The reaction is exothermic, and it is nece saty to add a heat exchanger to keep its temperature below 315 K. A heat exchanger with UA = 3000 J/s K is available for use. The coolant enters at a rate of 100 kg/s and a temperature of 285 K. 

Is the heat exchanger and coolant flow rate adequate to keqi the reactor temperature below 315 K Plot temperature, C, Cg. and Cc a.s a function of lime. 

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Section 13.3 Semibatch Reactors with a Heat Exchanger... 

In a semibatch emulsion homopolymer reactor, monomer is converted into polymer via a strongly exothermic reaction [2, 42]. First, water, surfactant, and initiator are loaded into the reactor. Then, monomer and heat are added to start the polymerization reaction, and after some period of time (in which the reaction sites have been formed), heat generated by the polymerization is removed in order to have an adequate reactor temperature control. Once the entire monomer load has been added, the temperature is increased to exhaust the monomer down to a small prespecified value. The monomer addition and heat exchange rates must be coordinated so that the batch is finished as soon as possible with adequate safety margin and... 

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