2.3. NF concentrate treatment experiments using AOPs
2.3.1. Experimental set-up
UV254 photolysis, ozonation and UV/O3 experiments were all carried out in a 5-L cylindrical acrylic reactor (450 mm height, 120 mm diameter). A 15 W low-pressure mercury lamp which emits UV light mainly at 254 nm was introduced into the centre of the reactor and kept separated from the feed water using a quartz cooling jacket. The temperature of the feed solution was maintained at 20 °C by the circulating water. Ozone gas was fed into the reactor through a microporous titanic plate situated at the bottom of the reactor. The flow rate of 1 L min−1 and ozone concentration of 4 mg L−1 were applied in our study, which was based on previous literatures [23] and [24]. The ozone generator (CF-G-3-10G, Qingdao Guolin Industry Co., China) was used to produce ozone from pure oxygen (99.5%).