To continuously refine over for a long period of time without stopping operation even in the case where a material to be refined is an organic compound containing an easily blockable substance.

In a refining apparatus wherein a shower contact type baffle plate is arranged, an opening part 30 is formed on all faces of the shower contact type baffle plates 21, 22 and 23. As an opening diameter of the opening part 30, 3-30 mm is desirable, and it is recommended that total area of the opening part is within a range of 10-50% to an upper part area of the baffle plate. When the apparatus is used, an organic compound such as methacrylic acid, methacrylate ester, phthalic acid, maleic acid, or the like, containing an easily blockable substance can be refined continuously over a long period of time.