Abstract: Hydrogen peroxide in a hydrogen peroxide reservoir is supplied to an effluent. Ozone gas generated in an ozone generating apparatus is delivered through branched piping to two ozone supplying points and is supplied to the effluent. The ozone and the supplied hydrogen peroxide react to generate hydroxyl radicals. The hydroxyl radicals react with the materials in the effluent to decompose and remove them.

Abstract: In a plant cultivating apparatus for cultivating plants by using an artificial light source, partition walls having a high light reflectance are arranged in a cultivation area to divide the cultivation area into small spaces and in each small space a light-reflecting plate is arranged, and the distance between an artificial light source and a plant is narrowed to irradiate the plant with a light having a low illuminance. In accordance with a preferred embodiment, there is provided a plant cultivating apparatus comprising sets of pallets which have plants placed therein and are arranged in rows in a growing chamber where environmental conditions which are artificially controlled and which are moved in a direction radial to the row direction in accordance with the growth of plants, wherein all the peripheral surface of the growing chamber are covered with a reflecting plate having a high light reflectance.