Reactor systems

Abstract

A reaction system comprising a reactor containing a reaction process medium and a heat exchanger providing a conduit through which flows a heat transfer fluid in which measurement of the flow and temperature change of the heat transfer fluid across the reaction is used to determine the heat generated or absorbed by the reaction system and that determination is used to monitor and control the reaction wherein i. the average temperature difference between the heat transfer fluid and the processes fluid is from 1 to 1000° C. preferably 1 to 100° C. ii. the temperature differential (t si −t so ) of the heat transfer fluid across the reaction system is at least 0.1° C., preferably at least 1° C. iii. the linear velocity of the heat transfer fluid is at least 0.01 meters/second preferably 0.1 meters/second.

1 . A reaction system comprising a reactor containing a reaction process medium and a heat exchanger providing a conduit through which flows a heat transfer fluid wherein measurement of the flow and temperature change of the heat transfer fluid across the reaction is used to determine the heat generated or absorbed by the reaction system and that determination is used to monitor and control the reaction wherein 
 i. the average temperature difference between the heat transfer fluid and the processes fluid is from 1 to 1000° C.    ii. the temperature differential (t si −t so ) of the heat transfer fluid across the reaction system is at least 0.1° C.    iii. the linear velocity of the heat transfer fluid is at least 0.01 meters/second.    
     
     
         2 . A reaction system according to  claim 1 , in which the average temperature difference between the heat fluid and the process fluid is from 1 to 100° C.  
     
     
         3 . A reaction system according to  claim 1 , in which the temperature differential (t si −t so ) of the heat transfer fluid across the reaction system is at least 1° C.  
     
     
         4 . A reaction system according to  claim 1 , in which the linear velocity of the heat transfer fluid is at least 0.1 meters/second.  
     
     
         5 . A reaction system according to  claim 1 , in which the heat exchanger has sufficient surface area to ensure that a measurable temperature difference (t si −t so ) is observed in the heat transfer fluid as it passes across the reactor.  
     
     
         6 . A reaction system according to  claim 1 , in which (t si −t so ) is 10° C. or more.  
     
     
         7 . A reaction system according to  claim 1 , in which a temperature difference of above 5° C. is maintained between the process fluid and the inlet heat transfer fluid (t si ).  
     
     
         8 . A reaction system according to  claim 7 , in which the temperature difference is from 5° C. to 100° C.  
     
     
         9 . A reaction system according to  claim 1 , in which the heat transfer fluid flows at a velocity of at least 1 meter/second.  
     
     
         10 . A reaction system according to  claim 1 , in which the heat transfer fluid is supplied at substantially constant temperature and pressure.  
     
     
         11 . A reaction system according to  claim 1 , in which the heat exchanger for the reactor is a heat transfer coil, which passes through the reaction process medium.  
     
     
         12 . A reaction system according to claims  1 , in which the heat exchanger is a plate which is submerged in the reaction process medium.  
     
     
         13 . A reaction system according to  claim 1 , in which the heat exchanger is or forms part of the vessel wall.  
     
     
         14 . A reaction system according to  claim 1 , in which the heat transfer fluid is recycled.  
     
     
         15 . A reaction system according to  claim 11 , in which the diameter to length relationship of a heat transfer coil is calculated by first calculating the heat transfer area required using the formula  
         U.A.LMTD=m.Cp .( t   si   −t   so )( kW )  
       where U=overall heat transfer coefficient (kW.m −2 .K −1 ) 
 A=heat transfer area (m 2 )  
 m=mass flow rate of heat transfer fluid (kg/s)  
 LMTD=log mean thermal difference between service and process fluids (° C.)  
 Cp=specific heat of heat transfer fluid (kJ.kg −1 K −1 )  
 (t si −t so )=temperature (° C.) change in the heat transfer fluid between inlet and outlet  
 and the diameter to length relationship of the coil is developed to enable high Reynolds number in the heat transfer fluid without an excessive pressure drop.  
 
     
     
         16 . A reaction system according to claims  12 , in which the heat transfer area is calculated from the formula  
         U.A.LMTD=m.Cp .( t   si   −t   so )( kW )  
       where U=overall heat transfer coefficient (kW.m −2 .K −1 ) 
 A=heat transfer area (m 2 )  
 m=mass flow rate of heat transfer fluid (kg/s)  
 LMTD=log mean thermal difference between service and process fluids (° C.)  
 Cp=specific heat of heat transfer fluid (kJ.kg −1 K −1 )  
 (t si −t so )=temperature (° C.) change in the heat transfer fluid between inlet and outlet  
 and the area to fluid path relationship is developed to enable high Reynolds number in the heat transfer fluid without an excessive pressure drop.  
 
     
     
         17 . A reaction system according to  claim 1 , in which the pressure drop across the conduits is 0.001 to 20 bar.  
     
     
         18 . A reaction system according to  claim 17 , in which the pressure drop across the conduits is 0.1 to 20 bar.  
     
     
         19 . A reaction system according to preceding  claim 1 , in which the heat exchanger is such that the area available for heat transfer between the reaction process medium and the heat transfer fluid may be varied according to the needs of the particular reaction.  
     
     
         20 . A reaction system according to  claim 19 , in which the area of heat transfer is varied by providing multiple heat transfer pipes each of which has a diameter and length relationship designed to provide a certain degree of heat transfer.  
     
     
         21 . A reaction system according to  claim 19 , in which the area of heat transfer is varied by providing multiple heat transfer plates each of which has a surface area and hydraulic path relationship designed to provide a certain degree of heat transfer.  
     
     
         22 . A reaction system according to  claim 19 , in which the heat exchanger is or forms part of the reaction vessel wall and consists of multiple conduits each designed to provide a certain degree of heat transfer.  
     
     
         23 . A method for synthesis reactions which comprises: 
 flowing a heat transfer fluid through a conduit disposed in a reactor comprising a reaction process medium and a heat exchanger; and    determining the flow and temperature change of the heat transfer fluid across the reaction, thereby determining the heat generated or absorbed by the reaction system and using that determination to monitor and control the reaction wherein    i. the average temperature difference between the heat transfer fluid and the processes fluid is from 1 to 1000° C.    ii. the temperature differential (t si −t so ) of the heat transfer fluid across the reaction system is at least 0.1° C.    iii. the linear velocity of the heat transfer fluid is at least 0.01 meters/second.    
     
     
         24 . The method according to  claim 23  for fast exothermic reactions.  
     
     
         25 . The method according to  claim 23 , wherein said reaction is a batch organic synthesis reactions carried out in reactions of 10 to 20,000 litres.  
     
     
         26 . The method according to  claim 23 , wherein said reaction is a bulk pharmaceutical synthesis reaction carried out in reactions of 10 to 20,000 litres.  
     
     
         27 . The method according to  claim 23 , wherein said reaction is a batch polymerisation reaction carried out in reactions of 10 to 20,000 litres.  
     
     
         28 . The method according to  claim 23 , wherein said reaction is a batch synthesis reactions of 10 to 20,000 litres used for unstable materials.  
     
     
         29 . The method according to  claim 23 , wherein said reaction is a batch inorganic synthesis reaction carried out in reactions of 10 to 20,000 litres.  
     
     
         30 . The method according to  claim 23 , wherein said reaction is a continuous reaction.  
     
     
         31 . The method according to  claim 23 , wherein said reaction is carried out in a reactor of from 1 ml to 10 litres capacity.