Multi-Stream Microchannel Device

A process, comprising:

• (a) flowing a first fluid through a plurality of first microchannels;
• (b) flowing a second fluid through a plurality of second microchannels;
• and
• (c) flowing at least a third fluid through a plurality of at least third microchannels, the plurality of at least third microchannels being in thermal communication with the plurality of first microchannels and with the plurality of second microchannels.

An apparatus, comprising:

• a first end and a second end;
• a first microchannel;
• a second microchannel;
• a third microchannel;
• a fourth microchannel;
• a fifth microchannel;
• a sixth microchannel;
• and
• a seventh microchannel, each microchannel defining a passageway between the first end and the second end, wherein each microchannel is in thermal communication with at least one of the other microchannels and the first microchannel has a cross-sectional area different from at least the second microchannel.