Mixing apparatus

A mixing apparatus capable of providing continuous stirred reactor performance comprising:

• a vessel;
• vertically extending agitator shaft means rotatably mounted in said vessel;
• first impeller means mounted on said shaft means and positioned within said vessel immediately subjacent to the top of said vessel but sufficiently spaced from said top to rotate, said first impeller means comprising impeller blades having a downward pitch of from about 15.degree. to about 60.degree.;
• second impeller means mounted on said shaft means and positioned within said vessel immediately superjacent to the bottom of said vessel but sufficiently spaced from said bottom to rotate, said second impeller means comprising impeller blades having an upward pitch of from about 15.degree. to about 60.degree.;
• third impeller means mounted on said shaft means and positioned within said vessel between said first and said second impeller means;
• paddle means mounted on said shaft means and positioned within said vessel between said second and said third impeller means, said paddle means comprising rectangular flat blades having their long dimension vertically aligned with said shaft means;
• and
• means for rotating said first, second and third impeller means and said paddle means sufficiently to provide continuous stirred reactor performance.