Fluid processing method including extraction

A fluid processing method, comprising:

• preparing at least two fluids to be processed, the at least two fluids including:
• a first fluid, being one of a fluid containing at least one kind of a material to be extracted and an extracting fluid containing at least one kind of extraction solvent that is capable of extracting said material to be extracted;
• and
• a second fluid, being the other of the fluid containing the at least one kind of the material to be extracted and the extracting fluid containing the at least one kind of extraction solvent that is capable of extracting said material to be extracted;
• introducing the at least two fluids into a processing device, the processing device comprising:
• at least two processing surfaces facing each other, at least one of the at least two processing surfaces rotating relative to the other about a rotating shaft, the at least two processing surfaces being capable of approaching to and separating from each other in an axial direction of the rotating shaft;
• maintaining a space between the at least two processing surfaces by a balance between a force that moves the at least two processing surfaces in a separating direction and a force that moves the at least two processing surfaces in an approaching direction,
• wherein the processing device includes:
• a first flow path for introducing the first fluid into the space between the at least two processing surfaces;
• and
• a second flow path, independent of the first flow path, for introducing the second fluid, the second flow path leading to at least one opening formed on at least one of the at least two processing surfaces, the second fluid being introduced into the space between the at least two processing surfaces through the at least one opening, and
• wherein the first fluid is introduced into the space between the at least two processing surfaces through the first flow path, forming a thin film fluid;
• and the second fluid is introduced into the thin film fluid of a laminar flow formed by the first fluid through the at least one opening;
• mixing the first fluid and the second fluid under the condition of the laminar flow as a thinned film;
• extracting the material to be extracted into the extraction solvent;
• discharging a mixed solution of the first fluid and the second fluid from the space between the at least two processing surfaces;
• settling the mixed solution of the first fluid and the second fluid discharged from the space between the at least two processing surfaces;
• and
• separating an intended product, in which the material to be extracted are extracted into the extraction solvent, by difference in specific gravities between solvents.