Fluidization and Solids Processing In Microchannel Devices

Abstract

This invention describes gas-solid, liquid-solid and gas-solid-liquid processes in microchannels devices including such processes as heterogeneous catalysis, particle formation, particle attrition, particle separation and adsorption or desorption of selected species. Various processes can be enhanced by the unique properties of microchannels such as the predominance of laminar flow, high rates of shear, high rates of heat transfer and high rates of mass transfer. Also encompassed by this invention are methods for the introduction to and removal from microchannels of particle containing fluid streams.

1 - 8 . (canceled) 
     
     
         9 . A method of conducting a chemical process, comprising:
 passing a gaseous stream through a microchannel;   controlling the flow of the gaseous stream to obtain a laminar flow regime;   wherein said gaseous stream comprises solid particulates;   wherein, after the solid particulates flow through the microchannel, further comprising a step of recycling the solid particulates so that the solid particulates pass through the microchannel for a second time.   
     
     
         10 . The method of  claim 9  wherein the solid particulates are made in the microchannel. 
     
     
         11 . The method of  claim 10  wherein the microchannel comprises an inlet, an outlet and walls defining the microchannel;
 wherein a second gas enters the microchannel through an orifice in a wall of the microchannel; 
 wherein the orifice is located between the inlet and the outlet; and 
 wherein the second gas is a reactant, diluent or quenching agent. 
 
     
     
         12 . (canceled) 
     
     
         13 . The method of  claim 9  wherein the solid particulates are catalyst particles. 
     
     
         14 . The method of  claim 13  further comprising a step of segregating the catalyst particles after they have been passed through the microchannel. 
     
     
         15 . The method of  claim 9  comprising passing the gaseous stream through a flow modifying manifold connection and through a microchannel array. 
     
     
         16 . (canceled) 
     
     
         17 . A method of conducting a chemical process, comprising:
 flowing a fluid stream into a header and through a flow modifying manifold connection to form a distributed flow;   wherein there is an interface between the header and a microchannel array; and wherein   (a) the distributed flow carries solid particulates through the microchannel array, or   (b) the distributed flow entrains solid particulates.   
     
     
         18 . The method of  claim 17  wherein the distributed flow entrains particulates and carries the entrained particulates through the microchannel array. 
     
     
         19 . The method of  claim 17  wherein the flow modifying manifold connection tends to distribute flow equally into the microchannel array. 
     
     
         20 . The method of  claim 17  wherein the fluid stream is a gaseous stream carrying solid particulates; wherein the microchannels in the microchannel array have the same length and the same gap; and further comprising a step of flowing the gaseous stream into the microchannel array such that such that the run up length of the microchannels in the microchannel array, x H , is less than the microchannel length; 
       wherein 
       
         
           
             
               
                 x 
                 H 
               
               = 
               
                 0.338 
                  
                 
                   
                     ( 
                     
                       H 
                       2 
                     
                     ) 
                   
                   2 
                 
                  
                 
                   ( 
                   
                     U 
                     v 
                   
                   ) 
                 
               
             
           
         
       
       wherein
 H is the smallest dimension (gap) of the microchannel, 
 U=superficial velocity of the gas in the microchannel 
 v=dynamic viscosity of the gas in the microchannel. 
 
     
     
         21 . A method of conducting a chemical process, comprising:
 flowing a first fluid stream carrying solid particulates through a microchannel;   wherein at least a portion of the solid particulates are agglomerated; and   passing a second fluid stream into the microchannel at a rate sufficient to cause a decrease in particle agglomeration.   
     
     
         22 . A method of conducting a chemical process, comprising:
 providing a first fluid stream carrying solid particulates into a microchannel in a direction opposing gravity;   wherein the microchannel has an inlet, an outlet and a length between the inlet and the outlet;   wherein the microchannel is further defined by at least one microchannel wall;   wherein said at least one microchannel wall comprises at least one orifice;   wherein said at least one orifice is located between the inlet and the outlet;   wherein the first fluid stream flows into the microchannel at a rate such that at least a portion of said particulates are pulled down by gravity and are not carried along the entire length of the microchannel; and   providing a second fluid that passes through the orifice, into the microchannel, and out of the outlet.   
     
     
         23 . The method of  claim 22  wherein at least a portion of the solid particulates are agglomerated; and wherein the second fluid passes into the microchannel at a rate sufficient to cause a decrease in particle agglomeration. 
     
     
         24 . A method of conducting a catalyzed chemical reaction in a microchannel reactor, comprising:
 providing a first fluid stream carrying solid catalyst particulates into a microchannel;   using the solid catalyst particulates to catalyze a reaction in the microchannel;   wherein the solid catalyst particulates move out of the microchannel; and   subsequently, recycling the solid catalyst particulates back into the microchannel in a continuous fashion.   
     
     
         25 - 29 . (canceled)