Methods and devices for minimizing membrane fouling for microfluidic separators

An apparatus, comprising:

• a microfluidic device disposed within a structure, the microfluidic device comprising:
• a porous membrane for separating a multiphase mixture in a fluid flow stream, wherein a pressure difference across the porous membrane is maintained below a capillary break-through pressure of a nonwetting fluid phase present in the multiphase mixture;
• at least one channel plate positioned proximate to the membrane, the at least one channel plate configured to direct the fluid flow stream along the porous membrane;
• wherein the porous membrane is arranged substantially tangent to an intended fluid flow direction of the multiphase mixture present in the fluid flow stream;
• and
• a microsieve is structured and arranged adjacent to and downstream of the membrane and includes a capillary fluid separator having microfabricated channels arranged substantially tangent to the fluid flow stream.

An apparatus, comprising:

• a housing positioned in a downhole oilfield tool, the housing having a fluid flow stream;
• a microfluidic device positioned in the housing, the microfluidic device comprising:
• a porous membrane for separating a multiphase mixture in the fluid flow stream, wherein a pressure difference across the porous membrane is maintained below a capillary break-through pressure of a nonwetting fluid phase present in the multiphase mixture;
• at least one channel plate positioned proximate to the membrane, the at least one channel plate configured to direct the fluid flow stream along the porous membrane;
• wherein the porous membrane is arranged substantially tangent to an intended fluid flow direction of the multiphase mixture present in the fluid flow stream;
• and
• a microsieve structured and arranged adjacent to and downstream of the porous membrane and includes a capillary fluid separator having microfabricated channels arranged substantially tangent to the fluid flow stream.