Development And Application Of Jacketed Reaction Calorimetry

The chemical industry develops by leaps and bounds,production,transportation is flammable,explosive,toxic and harmful,and the number of corrosive dangerous chemicals also increases greatly,which leads to many accidents.Most of the accidents are caused by the release of heat from the reaction decomposition of hazardous chemicals,so thermal analysis technology has become the best means to analyze the thermal hazard.At present,the instrument of chemical process heat measurement is developing slowly and the measurement is not accurate.In order to respond to the call of the country and society,the development and application of the entrapped reaction calorimetric technology is carried out.Through the comparison of the principle of the calorimeter,the heat flow method is used as the principle of the jacket type reaction calorimeter.According to its principle,the subsystem module is designed,which mainly includes the temperature control subsystem,the reaction tank subsystem,the data recording subsystem,the temperature control subsystem,the reactor subsystem,and the data recording subsystem.Data processing subsystem,sample weighing subsystem.The calculation method of thermodynamic parameters,such as heat transfer coefficient,adiabatic temperature rise and maximum temperature reached by out-of-control system,is calculated according to the calculation model of jacket type reaction calorimeter.The calibration experiments of sulfuric acid and sodium hydroxide were carried out to verify the accuracy of the calculation and the middle of sulfuric acid and sodium hydroxide.The accuracy is 99.6%through several groups of repeatability tests.In order to further improve its accuracy,the error analysis of the entrapped reaction calorimeter is carried out,and the least square fitting method is used to compensate.According to this design,the jacket reaction calorimeter can be applied to the thermal risk assessment of polyvinylidene fluoride emulsion synthesis process.After a series of experiments,the operating temperature T_p is 80?,and the highest temperature MTT is 265.26?.The temperature T_D24>300?corresponding to the maximum reaction rate of the out-of-control system TMRad is 24 hours,and the highest temperature MTSR reached by the out-of-control system is 88.7?.It is concluded that T_p<MTSR<MTT<T_D24,can determine the safety risk grade as grade 1.Similarly,the thermal risk assessment of the diazotization process for orange pigments is performed.The temperature of Tp is 26.5?,the highest technical temperature is320?,the maximum reaction time of TMRad is 24 hours,the temperature of T_D2424 is60.6?,the maximum temperature of runaway system is 37.77?.The result shows that Tp<MTSR<TD24<MTT,Be able to determine a security risk level of 2;The thermal risk assessment shows that the operating temperature?T_p?and the maximum temperature?MTT?of the process are 3.5?,100?,and the maximum reaction rate of the non-control system TMRad is 24 hours,T_D2424 is 101.6?,and the out-of-control system is out-of-control system.The highest temperature that can be reached is 5.43?,T_p<MTSR<MTT<T_D24,can determine the safety risk grade is 1;The thermal risk assessment of tetrafluorobenzyl chloride synthesis process showed that the operating temperature?T_p?was 88?,the technical maximum temperature?MTT?was 88?,and the maximum reaction rate of the out-of-control system was up to 24 hours?TMRad?.The corresponding temperature T_D2424 was 300?.And the highest temperature MTSR can be reached by the out-of-control system is 95.7?.It is concluded that T_p=MTT<MTSR<T_D24,can determine the level of safety risk to be level 3;2,4-dinitrochloride According to the thermal risk assessment of benzene synthesis process,the operating temperature?T_p?is 80.2?,the maximum temperature of technology?MTT?is 242?,and the maximum reaction rate of out-of-control system?TMRad?is 24 hours,the corresponding temperature(T_D24)is 258?.And the maximum temperature MTSR of the out-of-control system is 111.9?.It is concluded that T_p<MTSR<MTT<T_D2424 can determine that the reaction safety risk level of the process is grade 1.In addition,it can be used for the optimization analysis of technological parameters,such as the process of preparing graphene oxide.Through the calorimetric experiment,the optimum operating conditions for the safe and efficient production of graphene oxide are as follows:stirring speed is 250 rmin,feeding time is 60 minutes.The feed temperature is 0?and the reaction temperature is 20?in the middle temperature stage.